WO2023153963A1

WO2023153963A1 - Configuration of transmitter circuitry

Info

Publication number: WO2023153963A1
Application number: PCT/SE2022/050149
Authority: WO
Inventors: Miguel Lopez; Talha KHAN; Leif Wilhelmsson; Henrik Sjöland; Mehrnaz AFSHANG; Andreas HÖGLUND; Ning He
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2022-02-11
Filing date: 2022-02-11
Publication date: 2023-08-17

Abstract

A wireless communication device (110), WCD, receives (210) information from a network node (120). The received information indicates a status of an uplink channel. The WCD selects (220) a configuration of transmitter circuitry (112) of the WCD based on the received information, and transmits (230) to the network node using the selected configuration of the transmitter circuitry. In some embodiments, the received information represents a measurement value or an estimated channel condition. In some embodiments, selecting a configuration of the transmitter circuitry comprises selecting between using different components (501, 502) of the transmitter circuitry. In some embodiments, selecting a configuration of the transmitter circuitry comprises selecting a configuration of frequency generation circuitry (401), a power amplifier (402), linearization circuitry (403), a digital to analog converter (404), or reconstruction filtering (405) located after a digital to analog converter.

Description

Configuration of transmitter circuitry

Technical field

The present disclosure generally relates to wireless communication technology, and in particular to configuration of transmitter circuitry of a wireless communication device.

Background

Performance of wireless communication between a wireless communication device (WCD) and nodes in a wireless communication network may be evaluated based on various criteria/factors. In some scenarios, low latency and high reliability may be the most important aspects, while in other scenarios it may be more important to achieve high data rate or low energy consumption. It is typically difficult to achieve high performance with respect to all such criteria at the same time, so tradeoffs may need to be made when constructing WCDs, when designing wireless communication networks, and/or when performing scheduling of communication in a wireless communication network.

Summary

Embodiments of methods, wireless communication devices, network nodes, etc. are provided herein for addressing one or more of the aforementioned issues.

A first aspect provides embodiments of a method at a wireless communication device (WCD). The method comprises receiving information from a network node. The received information indicates a status of an uplink channel. The method comprises selecting, based on the received information, a configuration of transmitter circuitry of the WCD, and transmitting to the network node using the selected configuration of the transmitter circuitry.

A second aspect provides embodiments of a WCD. The WCD comprises transmitter circuitry. The WCD is configured to receive information from a network node. The received information indicates a status of an uplink channel. The WCD is configured to select, based on the received information, a configuration of transmitter circuitry of the WCD, and transmit to the network node using the selected configuration of the transmitter circuitry.

The WCD may for example comprise processing circuitry configured to cause the WCD to perform the method as defined in any of the embodiments of the first aspect disclosed herein.

The WCD may for example comprise processing circuitry and one or more memory. The one or more memory may for example contain instructions executable by the processing circuitry for causing the WCD to perform the method as defined in any of the embodiments of the first aspect disclosed herein.

A third aspect provides embodiments of a method at a network node. The method comprises obtaining information indicating a status of an uplink channel, and transmitting the information to a WCD for the WCD to select a configuration of transmitter circuitry of the WCD based on the information. The method comprises receiving a transmission from the WCD.

A fourth aspect provides embodiments of a network node. The network node is configured to obtain information indicating a status of an uplink channel, and transmit the information to a WCD for the WCD to select a configuration of transmitter circuitry of the WCD based on the information. The network node is configured to receive a transmission from the WCD.

The network node may for example comprise processing circuitry configured to cause the network node to perform the method as defined in any of the embodiments of the third aspect disclosed herein.

The network node may for example comprise processing circuitry and one or more memory. The one or more memory may for example contain instructions executable by the processing circuitry for causing the network node to perform the method as defined in any of the embodiments of the third aspect disclosed herein. A fifth aspect provides embodiments of a method at a network node. The method comprises obtaining information indicating a status of an uplink channel. Obtaining the information comprises performing a measurement or estimating a channel condition. The method comprises selecting, based on the obtained information, a configuration of transmitter circuitry of a WCD. The method comprises transmitting, to the WCD, an indication of the selected configuration of the transmitter circuitry.

A sixth aspect provides embodiments of a network node. The network node is configured to obtain information indicating a status of an uplink channel. Obtaining the information comprises performing a measurement or estimating a channel condition. The network node is configured to select, based on the obtained information, a configuration of transmitter circuitry of a WCD. The network node is configured to transmit, to the WCD, an indication of the selected configuration of the transmitter circuitry.

The network node may for example comprise processing circuitry configured to cause the network node to perform the method as defined in any of the embodiments of the fifth aspect disclosed herein.

The network node may for example comprise processing circuitry and one or more memory. The one or more memory may for example contain instructions executable by the processing circuitry for causing the network node to perform the method as defined in any of the embodiments of the fifth aspect disclosed herein.

Brief description of the drawings

In what follows, example embodiments will be described in greater detail with reference to the accompanying drawings, on which:

Fig. 1 illustrates a wireless communication device (WCD) and a network node, according to some embodiments;

Fig. 2 is flow chart of a method at a WCD, according to some embodiments;

Fig. 3 is flow chart of a method at a network node, according to some embodiments;

Fig. 4 illustrates examples of components of transmitter circuitry of a WCD;

Fig. 5 illustrates an example selection between different components of transmitter circuitry of a WCD;

Fig. 6 is flow chart of a method at a network node, according to some embodiments; and

Fig. 7 illustrates use of reference signal received power (RSRP) for selection of a transmitter chain configuration (TCC).

All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the respective embodiments, whereas other parts may be omitted or merely suggested. Any reference number appearing in multiple drawings refers to the same object or feature throughout the drawings, unless otherwise indicated. Detailed description

Throughout the present disclosure, all references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. It will be appreciated that the word "comprising" does not exclude other elements or steps. The word “oh’ is not to be interpreted as an exclusive or (sometimes referred to as “XOR”). On the contrary, expressions such as “A or B” covers all the cases “A and not B”, “B and not A” and “A and B”. The mere fact that certain measures/features are recited in mutually different dependent claims or embodiments does not indicate that a combination of these measures/features cannot be used to advantage. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features and advantages of the enclosed embodiments will be apparent from the following description.

As used herein, a wireless communication device (WCD) is a device capable of communicating wirelessly with network nodes of a communication network and/or with other WCDs. Communicating wirelessly may for example involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. The WCD may for example be a user equipment (UE) in the terminology of the third generation partnership project (3GPP). However, the WCD need not necessarily be operated by a human user, and may for example be a machine-to-machine (M2M) device or a machine type communication (MTC) device. Examples of a WCD include, but are not limited to, a smart phone, a mobile phone, a cell phone, a voice over IP (VoIP) phone, a wireless local loop phone, a desktop computer, a personal digital assistant (PDA), a wireless cameras, a gaming console or device, a music storage device, a playback appliance, a wearable terminal device, a wireless endpoint, a mobile station, a tablet, a laptop, a laptop-embedded equipment (LEE), a laptop-mounted equipment (LME), a smart device, a wireless customer-premise equipment (CPE), a vehicle-mounted wireless terminal device, etc.

As used herein, a network node is a node (of a communication network) which is capable of communicating wirelessly with a WCD and/or with other network nodes of the communication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).

Power efficiency is key in radio transmitters, especially in battery powered and energy harvesting communications devices. The analog front end (AFE) plays a significant role in both the power/energy consumption and performance of the transmitter. In addition to power efficiency, radio designers also need to make sure that the radio satisfies other performance requirements. The AFE design involves a trade-off between power consumption/efficiency and performance. Generally, it is possible to increase power efficiency and/or reduce the power consumption by relaxing requirement for the AFE design. For example, the average output power of a power amplifier (PA) depends on the linearity requirements, which in turn determine the distortion in the transmitted signal and the out-of-band emissions. The effective isotropic radiated power can be increased if the linearity requirements are relaxed. The frequency generation circuitry also consumes a significant amount of power. The power consumption is related to how accurate the frequency generation needs to be. For example, there are situations where a phase locked loop (PLL) is not needed and where a free-running oscillator can be used, whereby the power/energy consumption may be significantly reduced.

Requirements on the accuracy of the transmitter circuitry are usually chosen according to some specifications that reflect a worst-case scenario. This means that the design trade-offs are made based on fixed assumptions and irrespective of the congestion of the wireless medium or other environmental factors that a radio transmitter experiences at any given time. Environmental factors include the prevailing network conditions such as user load, interference level, application (or quality of service QoS) requirements, etc. as well as the local conditions of the WCD, such as its power budget, power availability pattern, etc. Because of this, the radio transmitter does not operate as efficiently as it could have been doing if the requirements were adapted to the environment.

At least some embodiments herein propose an environment adaptive radio transmitter in a power limited WCD, where the transmitter circuitry is tuned/adapted/selected according to environmental conditions in order to prolong the WCD’s battery life or more generally to reduce the power/energy consumption of the WCD. According to at least some embodiments, the network measures and/or estimates the environmental conditions and sends an indication about the environmental conditions to the WCD, which then tunes/adapts/selects its transmitter circuitry based on the received indication.

Embodiments proposed herein include methods and a signaling framework to enable transmit chain (or transmitter circuitry) adaptation at a WCD capable of performing such transmit chain adaptation for uplink transmission. The goal is to optimize a certain utility such as minimizing WCD energy consumption, prolonging WCD battery life, maximizing effective signal to noise ratio (SNR), reducing end-to-end communication latency, etc. By adapting their transmitter circuitry in this way, energy harvesting WCDs may be able to reduce their latency, since it takes less time for the WCDs to harvest the necessary energy to make transmissions.

Fig. 1 illustrates a WCD 110 and a network node 120, according to some embodiments. The network node 120 may for example be part of a communication network (such as a cellular network) configured to communicate with the WCD 110 using one or more radio access technologies such as Bluetooth, Wi-Fi, GSM (Global System for Mobile communication), UMTS (Universal Mobile Telecommunications System), LTE (Long Term Evolution), or NR (New Radio).

The WCD 110 comprises receiver circuitry 111 for receiving signals 130 from the network node 120 and transmitter circuitry 112 for transmitting signals 140 to the network node 140. The receiver circuitry 111 and the transmitter circuitry 112 may for example be provided together in the form of combined/integrated circuitry, or may for example be provided as separate sets of circuitry.

The WCD 110 may for example comprise processing circuitry 113 configured to cause the WCD 110 to perform one or more of the actions and method steps described below with reference to Fig. 2. The WCD 110 may for example comprise one or more memory 114 containing instructions executable by the processing circuitry 113 for causing the WCD 110 to perform one or more of the actions and method steps described below with reference to Fig. 2.

The processing circuitry 113 may for example comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide WCD functionality either alone or in conjunction with other WCD components.

The one or more memory 114 may for example comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 113.

The network node 120 comprises receiver circuitry 121 for receiving signals 140 from the WCD 110 and transmitter circuitry 122 for transmitting signals 130 to the WCD 110. The receiver circuitry 121 and the transmitter circuitry 122 may for example be provided together in the form of combined/integrated circuitry, or may for example be provided as separate sets of circuitry.

The network node 120 may for example comprise processing circuitry 123 configured to cause the network node 120 to perform one or more of the actions and method steps described below with reference to Fig. 3 and/or Fig. 6. The network node 120 may for example comprise one or more memory 124 containing instructions executable by the processing circuitry 123 for causing the network node 120 to perform one or more of the actions and method steps described below with reference to Fig. 3 and/or Fig. 6. The processing circuitry 123 may for example comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide WCD functionality either alone or in conjunction with other WCD components.

The one or more memory 124 may for example comprise any form of volatile or non-volatile computer readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by processing circuitry 123.

The person skilled in the art is well-aware that WCDs and network nodes may typically include many more parts/components than those described above with reference to Fig. 1.

Fig. 2 is flow chart of a method 200 at a WCD, according to some embodiments. The method 200 may for example be performed at the WCD, or by the WCD, or by one or more components of the WCD. The method 200 may for example be performed at the WCD 110 in Fig. 1. Reference numbers from Fig 1 will be used herein when describing the method 200, but it will be appreciated that the WCD 110 and the network node 120 in Fig. 1 only serve as examples.

The method 200 comprises receiving 210 information from a network node (for example from the network node 120 in Fig. 1). The received information indicates a status of an uplink channel. The uplink channel may for example be a channel for transmissions from the WCD 110 to the network node 120 and/or for transmissions from other WCDs to the network node 120 (in contrast to a downlink channel which is for transmissions in the downlink from the network node 120 to one or more WCDs).

The method 200 comprises selecting 220 a configuration of transmitter circuitry 112 of the WCD 110 based on the received information (in other words, based on the information received at step 210). The transmitter circuitry 112 for may for example comprise one or more components adapted for preparing/generating signals to be transmitted from the WCD 110 to the network node 120. The transmitter circuitry 112 may for example comprise an analog front end (AFE) and/or a transmitter chain.

The method 200 comprises transmitting 230 to the network node 120 using the selected configuration of the transmitter circuitry 112 (in other words, using the configuration selected at step 220). The transmission transmitted at step 230 may for example be any type of uplink transmission from the WCD 110 to the network node 120, and may for example comprise a control signal and/or a data signal and/or a reference signal.

Fig. 3 is flow chart of a method 300 at a network node, according to some embodiments. The method 300 may for example be performed at the network node, or by the network node, or by one or more components of the network node. The method 300 may for example be performed by a network node in cooperation with a WCD performing the method 200 in Fig. 2. The method 300 may for example be performed at the network node 120 in Fig. 1. Reference numbers from Fig 1 will be used herein when describing the method 300, but it will be appreciated that the WCD 110 and the network node 120 in Fig. 1 only serve as examples.

The method 300 comprises obtaining 310 information indicating a status of an uplink channel. The information obtained at step 310 may for example be the same information as received at step 210 in the method 200 in Fig 2. The uplink channel may for example be a channel for transmissions from the WCD 110 to the network node 120 and/or for transmissions from other WCDs to the network node 120 (in contrast to a downlink channel which is for transmissions in the downlink from the network node 120 to one or more WCDs).

The method 300 comprises transmitting 320 the information (in other words, the information obtained at step 310) to a WCD 110, for the WCD 110 to select a configuration of transmitter circuitry 112 of the WCD 120 based on the information.

The method 300 comprises receiving 330 a transmission from the WCD 110. The transmission received at step 330 may for example be the same transmission as transmitted at step 230 in the method 200 in Fig. 2. Hence, transmission received at step 330 may use the selected configuration of the transmitter circuitry 112 of the WCD 110.

According to the methods 200 and 300 described above, a configuration of transmitter circuitry 112 of the WCD 110 is selected based on information indicating a status of an uplink channel. The configuration of transmitter circuitry 112 may be selected to be appropriate in view of the status of the uplink channel. If channel conditions of the uplink channel are not so favorable (for example, many WCDs are currently using the network and an interference level measured at the network node is high), then it may be important for the WCD 110 to provide high quality transmissions in the uplink, for the network node 120 to be able to receive them. But if channel conditions of the uplink channel are more favorable (for example, very few WCDs are currently using the network and an interference level measured at the network node 120 is low), then the network node 120 may be able to receive transmission from the WCD 110 even if those transmissions are of lower quality. In the case of favorable channel conditions, the WCD 110 may therefore be able to use a simpler, less energy consuming, configuration of the transmitter circuitry 112. This way of saving energy may be particularly useful for WCDs with very limited energy supply (for example small battery) or WCDs which rely on harvesting energy from its environment (also referred to as zero-energy devices/UEs). WCDs with such limited energy supply may also be referred to as power-limited WCDs, and may for example include narrowband internet of things (NB-loT) UEs.

The methods 200 and 300 described above refer to information indicating a status of an uplink channel (see for example steps 210, 220, 310, 320). The status of the uplink channel is preferably measured/estimated by the network node 120, since it is the network node 120 that will be receiving uplink transmissions from the WCD 110. It could also be possible to have the WCD 110 perform measurements to estimate the status of the uplink channel, but this would typically be more unreliable as it would rely on assumptions regarding uplink/downlink reciprocity (because the WCD 110 would be measuring on downlink signals rather than uplink signals) and would consume extra energy at the WCD 110. Measurements and/or processing needed for estimating the status of the uplink channel may therefore preferably be made at the network node 120. Note that there is typically more energy available at the network node 120 than at the WCD 110.

Various embodiments and examples will be described below, referring back to the embodiments described above with reference to Figs. 1-3.

Fig. 4 illustrates examples of components of transmitter circuitry 112 of a WCD 110, according to some embodiments. It will be appreciated that transmitter circuitry 112 could comprise other components than those depicted in Fig. 4, and that the components depicted in Fig. 4 need not necessarily be arranged as depicted in Fig. 4. The person skilled in the art will understand that transmitter circuitry 112 of a WCD may include the appropriate means for preparing/generating signals to be transmitted from the WCD, and that such means may for example be implemented via various combinations of hardware components and software components. The transmitter circuitry 112 (or a portion thereof) may sometimes be referred to as an analog front end (AFE) and/or a transmitter chain.

The transmitter circuitry 112 may for example comprise frequency generation circuitry 401 for generating a desired frequency. The frequency generation circuitry 401 may for example comprise a phase locked loop (PLL) and/or a free running oscillator. A PLL may provide more accurate and/or reliable frequency generation, but the free running oscillator may consume less energy. The transmitter circuitry 112 may for example comprise a power amplifier 402. The transmitter circuitry 112 may for example comprise linearization circuitry 4O3.The transmitter circuitry 112 may for example comprise a digital to analog converter (DAC) 404. The transmitter circuitry 112 may for example comprise reconstruction filtering 405 (for example implemented as one or more filters) located after the digital to analog converter 404. In other words, in the process of generating signals to be transmitted by the WCD 110, reconstruction filtering 405 may be applied after digital to analog conversion 404. The person skilled in the art knows how the various components depicted in Fig. 4 may be arranged and connected to each other to prepare/generate signals to be transmitted from the WCD 110. For example, a DAC may convert the digital baseband signal to analog. Mixers may be used to upconvert the baseband signal (that is, translate its center frequency) to the final RF frequency. There can be more than one mixer when upconversion is performed in stages, starting with an intermediary frequency before reaching the final frequency. Various filters may be used to reject undesired signals such as local oscillator (LO) harmonics or image noise generated by the mixers. A mixer may multiply the input signal with a signal generated by a LO. LOs are typically implemented using a frequency synthesizer. Many frequency synthesizers utilize phase locked loops (PLLs) which typically comprise a fixed reference oscillator (for example a crystal) a phase/frequency detector, a loop filter and a voltage controlled oscillator (VCO) arranged in a feedback network. A power amplifier may amplify the RF signal, which is typically transmitted through a filter to suppress harmonics.

Fig. 5 illustrates selection between different components of transmitter circuitry 112 of a WCD 110, according to some embodiments. As illustrated in Fig. 5, the transmitter circuitry 112 may include a switch 500 which can be employed to switch between a first set of components 501 and a second set of components 502. The first set of components 501 may for example provide a high quality signal with low interference, while the second set of components 502 is able to provide a signal with acceptable quality and interference using much less energy than the first set of components 501. As illustrated in Fig. 5, a third set of components 503 may for example be used regardless of whether the switch 500 selects the first set of components 501 or the second set of components 502.

It will be appreciated that the setup shown in Fig. 5 merely serves as an example, and that many other arrangements are possible. The simple mechanical switch 500 shown in Fig. 5 could for example be replaced by any other type of switch or device/arrangement for switching between different components. In some embodiments, at least some of the components of the transmitter circuitry 112 may be implemented as software, and there may be no need for a mechanical switch for switching between such software components. In other words, the switch 500 could in some case be implemented by software. Further, the components 503 indicated in Fig. 5 to the right of the switch 500 merely serves as an example, and it will be appreciated that one or more components of the transmitter circuitry 112 may be arranged before the switch 500 and the components 501 and 502, and one or more additional components of the transmitter circuitry 112 may be arranged after the switch 500 and the components 501 and 502 such that the additional components are used regardless whether the switch 500 selects the first set of components 501 or the second set of components 502. It will be further appreciated that any of the sets 501-503 of components may for example include one or more components or circuit parts, and such components or circuit parts could be co-located in a combined circuit arrangement in the WCD 110, or could be arranged at separate locations of the WCD 110.

In the method 200, the step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between using different components of the transmitter circuitry 112, as illustrated in Fig. 5. The step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting whether to inactivate (or deactivate or switch off, or put in some form of power saving mode) at least one component of the transmitter circuitry 112. For example, some components which are not currently necessary may be inactivated to save energy.

As an alternative or complement to selecting between different components to be used, the step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between using different settings of at least one component of the transmitter circuitry 112. The step 220 may for example select between a first setting (or first set of parameter values) which provides a high quality signal with low interference, and a second setting (or second set of parameter values) which is able to provide a signal with acceptable quality and interference using less energy than the first setting.

In the method 200, the step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting a configuration of frequency generation circuitry 401 , and/or a power amplifier 402, and/or linearization circuitry 403, and/or a digital to analog converter 404, and/or reconstruction filtering located after a digital to analog converter 405. Oscillator frequency accuracy may for example be adjusted/tuned, because aiming for a lower frequency accuracy may help reduce the power consumption. High frequency accuracy may for example be expressed as low average frequency error, and low frequency accuracy may for example be expressed as high average frequency error. Oscillator phase noise (such as random fluctuations with time) may for example be adjusted/tuned, because tolerating more out-of- channel emissions and in-channel phase noise may help reduce power consumption. Power amplifier linearity may for example be adjusted/tuned, because tolerating a non-linear operation may help reduce energy consumption. Linearization circuitry may for example be adjusted/tuned (for example, digital pre-distortion could be turned on/off, or have more or less complexity), because tolerating a more non-linear operation may allow linearization circuitry to be turned off or operate with less power consumption. A noise emission level of the transmitter circuitry (or transmitter chain) may be adjusted/tuned, because operating with a relaxed noise emission level may help reduce the power consumption. A transmit power may for example be adjusted/tuned, because increasing the transmit power may improve chances of successful reception at the network node 120, which may reduce latency and also obviate the need of a packet retransmission. Transmission frequency and/or bandwidth may for example be adjusted/tuned, because changing the carrier frequency and/or transmission bandwidth may change the power consumption of one or more components in the transmitter circuitry, and may also help create larger guard-bands around the carriers. A center of frequency of a sub-band within the frequency band may be adjusted/tuned, because this may be employed to reduce interference and thus maximize the effective signal to noise and interference ratio (SI NR). For example, the bandwidth of operation (say 20 MHz) can be divided into a number of sub-bands (say 4 sub-bands of 5 MHz) Each of these has its own center frequency. If the transmitter is going to send a 5 MHz signal and other WCDs are allocated bandwidth in the remaining 15 Mhz, then the network can choose which 5 Mhz chunk to allocate to the low power WCD (and this chunk also has a center frequency). One or more digital to analog converters (DACs) may be adapted/tuned, because reducing the dynamic range and sample rate of DACs can reduce power consumption in a trade-off with spectral purity of the transmitter. One or more reconstruction filters after (typically directly after) the DAC(s) may be adjusted/tuned, because, reducing filter selectivity (for example by reducing filter order) can reduce power consumption when increased emissions can be tolerated.

In an example, the network node 120 periodically broadcasts information about tolerable oscillator frequency generation accuracy and phase noise for each of the configured uplink radio frequency channels (or more generally for the configured radio frequency ranges) in a given cell. When the cell is lightly loaded in the uplink, the network node 120 may relax the oscillator accuracy requirements on certain bands. A low-power WCD may then adapt its local oscillator generation circuitry accuracy accordingly in order to reduce its energy consumption and therefore the overall energy consumption as well.

In another example, consider the trade-off between power consumption/performance of different components of transmit chain and EIRP. For instance, while keeping the overall device power consumption within a certain limit, the power consumption of certain components within the transmit chain can be increased at the expense of the others. One example is to allow for a higher EIRP by reducing the power consumption of oscillators (for example, by allowing for a higher error in frequency generation). The higher transmit signal power may improve the received signal power at the receiver but the transmit signal will likely suffer from a more severe frequency impairment.

The step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between a PLL and a free-running oscillator. The PLL may provide more accurate/reliable frequency generation, but a free- running oscillator may be sufficient when channel conditions are favorable. Energy may be saved by using the free-running oscillator when possible. The step 220 of selecting a configuration of the transmitter circuitry 112 may therefore comprise selecting whether to inactivate the PLL.

The step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between at least a first configuration and a second configuration, where the second configuration is associated with (or causes or leads to) lower energy consumption than the first configuration. The first configuration may for example be associated with higher degree of linearity (in other words, better linearity) than the second configuration, and/or higher (in other words, better) frequency accuracy than the second configuration, and/or less phase noise than the second configuration, and/or lower noise emission level than the second configuration. The second configuration which is more energy efficient than the first configuration may for example be employed if the uplink channel conditions are favorable (in other words, good channel conditions), while the first configuration which has higher performance but also higher energy consumption may be employed if the uplink channel conditions are less favorable (in other words, poor channel conditions). The step 220 of selecting a configuration of the transmitter circuitry 112 may for example be performed with an aim to reduce the overall energy consumption at the WCD 110.

The step 220 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between at least a first configuration and a second configuration, where, for a certain level of energy consumption, the second configuration is associated with (or causes or leads to) higher effective isotropic radiated power (EIRP) than the first configuration, and/or lower block error rate (BLER) than the first configuration, and/or higher throughput than the first configuration, and/or lower false alarm rate (for example as a physical random access channel, PRACH, performance metric) than the first configuration, and/or higher miss detection rate (for example as a PRACH performance metric) than the first configuration, and/or lower interference caused than the first configuration, and/or higher effective uplink signal to interference and noise ratio (SI NR) than the first configuration. In other words, the first and second configurations need not necessarily consume different quantities/amounts of energy, but the second configuration may be more energy-efficient in the sense that it provides higher effective isotropic radiated power, and/or lower block error rate, and/or higher throughput, and/or lower false alarm rate, and/or higher miss detection rate, and/or lower interference, and/or higher effective uplink for a certain amount of consumed energy. The second configuration may for example achieve this by applying relaxed requirements regarding things such as accuracy, quality, linearity, or noise. The first configuration may for example be associated with a higher degree of linearity, or higher frequency accuracy, or less phase noise, or lower noise figure, but the second configuration may provide acceptable performance in the current channel conditions. The second configuration may for example achieve lower BLER than the first configuration, higher throughput than the first configuration, lower false alarm rate than the first configuration, higher miss detection rate than the first configuration, lower self-interference caused than the first configuration, and/or higher effective SI N R than the first configuration by using a filter with worse stop band (that is, less attenuation of undesired out of band emissions), because such a filter would introduce less intersymbol interference. The step 220 of selecting a configuration of the transmitter circuitry 112 may for example be performed with the aim to maximize effective isotropic radiated power, or to satisfy one or more statistical performance metrics (such as a certain block error rate, throughput, miss detection rate, false alarm rate, etc.), or to minimize latency, or to minimize uplink interference to other users and network nodes (or minimizing intra- and/or inter-cell interference), or maximizing effective uplink signal to interference and noise ratio (SINR).

In some embodiments, the status of the uplink channel indicated by the information received at step 210 (and obtained at step 310 and transmitted at step 320) may comprise an uplink channel quality, and/or an interference level on the uplink, and/or a network load, and/or a tolerable frequency error level on the uplink, and/or a tolerable timing error level on the uplink, and/or a tolerable phase noise level on the uplink, and/or a tolerable error vector magnitude, EVM (EVM is a measure of distortion in the transmitter, induced by phase noise or other imperfections). Such an uplink channel status may for example have been obtained 210 by the network node 120 (or by some other entity) by performing one or more measurements and/or by performing one or more estimates. The network node 120 may for example have performed one or more measurements on one or more uplink signals received from the WCD 110 or from some other WCD. However, embodiments may also be envisaged in which the network node 120 obtains the information at step 310 by receiving, from some other entity (such as from another network node) an indication of the status of the uplink channel. In other words, in some embodiments, the network node 120 does not necessarily need to perform any measurements to obtain 310 the information which it then transmits to the WCD 110 at step 320, and which the WCD 110 then receives at step 210.

In some embodiments, the information received at step 210 (and obtained at step 310 and transmitted at step 320) may represent (or may include) at least a measurement value or an estimated channel condition. The network node 120 may for example report measurement values to the WCD 110, or may process measurement values to obtain estimated channel conditions which are then reported to the WCD 110.

In some embodiments, the selection at step 220 of a configuration of transmitter circuitry 112 of the WCD 110 may be based on the information received at step 210 and a level of energy available at the WCD 110. If the WCD 110 currently only as very limited energy available, a less energy-consuming configuration may be employed compared to when there is plenty of energy available at the WCD 110.

In some embodiments, the selection at step 220 of a configuration of transmitter circuitry 112 of the WCD 110 may be based on the information received at step 210 and an energy availability pattern of the WCD 110. It may for example be possible to predict whether energy will be scarce at the WCD 110 so that an energy-saving configuration should be used, or whether the WCD 110 will soon have plenty of energy, whereby a more energy-consuming configuration may be employed. The WCD 110 may for example be configured to harvest energy from its environment, for example from heat, vibrations, or light. At least some energy harvesting WCDs may have an energy availability pattern which allows relatively reliable predictions to be made regarding future energy levels. For example, it may be easier to harvest energy from heat and sunlight during daytime than during the night, so the energy level of the WCD 110 can be relatively reliably predicted to be higher in the afternoon than in the middle of the night.

In some embodiments, the method 200 comprises receiving an indication of a plurality of candidate configurations of the transmitter circuitry 112. In such embodiments, the selection of the configuration of the transmitter circuitry 112 of the WCD 110 at step 220 may be made from among the plurality of candidate configurations. The candidate configurations may for example have been determined or selected by the network node 110 based on some criteria.

In some embodiments, the method 300 comprises transmitting, to the WCD 110, an indication of a plurality of candidate configurations of transmitter circuitry from which the WCD 110 is to select to the configuration of transmitter circuitry 112 of the WCD 110. The method 300 may for example comprise receiving an indication of a level of energy of the WCD 110 (for example a level of energy available to the WCD 110, for example in a battery), and selecting the plurality of candidate configurations of transmitter circuitry based on the level of energy of the WCD 110. If the energy level of the WCD 110 is low, candidate configurations associated with low energy consumption may for example be selected by the network node 120. The network node 120 may for example receive signaling from the WCD 110 indicating the level of energy of the WCD 110. The method 300 may for example comprise receiving an indication of an energy availability pattern of the WCD 110, and selecting the plurality of candidate configurations of transmitter circuitry based on the energy availability pattern of the WCD 110. It may for example be possible to predict whether energy will be scarce at the WCD 110 so that an energysaving configuration should be used, or whether the WCD 110 will soon have plenty of energy, whereby a more energyconsuming configuration may be employed. The WCD 110 may for example be configured to harvest energy from its environment, for example from heat, vibrations, or light. At least some energy harvesting WCDs may have an energy availability pattern which allows relatively reliable predictions to be made regarding future energy levels. For example, it may be easier to harvest energy from heat and sunlight during daytime than during the night, so the energy level of the WCD 110 can be relatively reliably predicted to be higher in the afternoon than in the middle of the night. The network node 110 may for example receive signaling from the WCD 110 indicating the energy availability pattern of the WCD 110.

In some embodiments, the information received at step 210 (and transmitted at step 320) also indicates a quality of service (QoS) requirement. A service to be used by the WCD 110 may for example require a certain QoS level. The network node 110 may inform the WCD 110 about the QoS requirement, so that the WCD 110 may select a configuration of the transmitter circuitry 112 which is suitable for the QoS requirement. A QoS requirement may for example be low delay tolerated (for voice services) vs larger delay tolerated (for things such as a downloading of a file).

In some embodiments, the method 200 comprises receiving an indication from the network node 120 to adjust a transmit power, and/or a transmit frequency, and/or a transmit bandwidth, and/or a center of frequency of a sub-band within a frequency band, and/or a modulation and coding scheme (MCS). In such embodiments, the transmitting to the network node 120 at step 230 may be performed in accordance with the indicated adjustment. In other words, the transmission at step 230 may use an adjusted transmit power, an adjusted transmit frequency, an adjusted transmit bandwidth, an adjusted center of frequency of a sub-band within a frequency band, and/or an adjusted MCS.

Similarly, in some embodiments, the method 300 may comprise transmitting an indication to the WCD 110 to adjust a transmit power, and/or a transmit frequency, and/or a transmit bandwidth, and/or a center of frequency of a subband within a frequency band, and/or a modulation and coding scheme (MCS). In such embodiments, the transmission received at step 330 may be in accordance with the indicated adjustment. The indication to adjust may for example be transmitted to the WCD 110 in response to a detection that link quality (for example measured in terms of signal to noise ratio, bit or block error rate, received signal strength or a combination of these) in the downlink is relatively good while link quality (for example measured in terms of signal to noise ratio, bit or block error rate, received signal strength or a combination of these) in the uplink is relatively bad. The good link quality in downlink and bad link quality in uplink may indicate that the network node 120 is experiencing interference on the uplink. This information can be used for scheduling WCDs on the uplink to facilitate transmitter circuitry adaptation in combination with other information as mentioned in previous embodiments and examples. For example, if the received signal strength is high but the SNR is low, then this is likely due to interference and the link quality may be determined to be bad. Thresholds may be employed for the link quality. For example, a signal 30 dB above the sensitivity of the receiver may be regarded as strong (that is, the receiver has sensitivity of -90 dBm and the received signal strength exceeds a threshold of -60 dBm). If at the same time the bit error rate is determined to be below a threshold (say 1%), then the receiver can determine that a significant portion of the received power corresponds to interference. The point here is that the receiver knows the bit error rate at the sensitivity level (say 1 %). The receiver expects 1 % bit error rate at -90 dBm, yet it gets more than 1 % at - 60 dBm, then there is likely a lot of interference.

In some embodiments, the selection at step 220 of the configuration of the transmitter circuitry 112 of the WCD 110 may be based on the information received at step 210 and a power level of a signal received (for example received from the network node 120) at the WCD 110. That signal received at the WCD 110 may for example be a reference signal. The power level may for example be a reference signal received power (RSRP) level. The power level of the received signal may for example be measured by the WCD 110. As described further below with reference to Fig. 7 and Table 1, a power level (such as a level of RSRP) of a received signal may indicate which configuration(s) of the transmitter circuitry 112 are suitable. The method 200 at the WCD 110 may for example comprise receiving an indication of a threshold, and the selection at step 220 of the configuration of the transmitter circuitry 112 of the WCD 110 may be based on whether the power level of the signal received at the WCD 110 exceeds the threshold. Correspondingly, the method 300 at the network node 120 may comprise transmitting an indication of a threshold for the WCD 110 to apply for a power level of a received signal when selecting 220 the configuration of the transmitter circuitry 112 of the WCD 110.

In the embodiments described above with reference to Figs. 1-3, the configuration of the transmitter circuitry 112 is selected at the WCD 110. In other embodiments, this selection can be made at the network node 120. Such embodiments will be described below with reference to Fig. 6.

Fig. 6 is flow chart of a method 600 at a network node, according to some embodiments. The method 600 may for example be performed at the network node, or by the network node, or by one or more components of the network node. The method 600 may for example be performed at the network node 120 in Fig. 1. Reference numbers from Fig 1 will be used herein when describing the method 600, but it will be appreciated that the WCD 110 and the network node 120 in Fig. 1 only serve as examples.

The method 600 comprises obtaining 610 information indicating a status of an uplink channel. The step of obtaining 610 the information comprises performing a measurement or estimating a channel condition. The information obtained at step 610 may for example be the same type of information as received at step 210 of the method 200 and/or obtained at step 310 of the method 300. The status of the uplink channel referred to at step 610 may for example comprise an uplink channel quality, and/or an interference level on the uplink, and/or a network load, and/or a tolerable frequency error level on the uplink, and/or a tolerable timing error level on the uplink, and/or a tolerable phase noise level on the uplink, and/or a tolerable error vector magnitude (EVM).

The method 600 comprises selecting 620 a configuration of transmitter circuitry 112 of a WCD 110 based on the information obtained at step 610. The selection step 620 may for example be analogous to the selection step 220 in the method 200, with the difference that the step 620 is performed at the network node 120 instead of at the WCD 110. The step of selecting 620 a configuration of the transmitter circuitry 112 may for example comprises selecting between different components of the transmitter circuitry, or selecting whether at least one component of the transmitter circuitry is to be inactivated, or selecting between different settings of at least one component of the transmitter circuitry. The step 620 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting a configuration of frequency generation circuitry 401, and/or a power amplifier 402, and/or linearization circuitry 403, and/or a digital to analog converter 404, and/or reconstruction filtering 405 located after a digital to analog converter. The step 620 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between a phase locked loop (PLL) and a free-running oscillator, or selecting whether a PLL is to be inactivated. The step 620 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between at least a first configuration and a second configuration, where the second configuration is associated with lower energy consumption than the first configuration. The step 620 of selecting a configuration of the transmitter circuitry 112 may for example comprise selecting between at least a first configuration and a second configuration, where, for a certain level of energy consumption, the second configuration is associated with higher effective isotropic radiated power than the first configuration, and/or lower block error rate than the first configuration, and/or higher throughput than the first configuration, and/or lower false alarm rate than the first configuration, and/or higher miss detection rate than the first configuration, and/or lower interference caused than the first configuration, and/or higher effective uplink signal to interference and noise ratio (SINR) than the first configuration. The first configuration may for example be associated with a higher degree of linearity than the second configuration, and/or higher frequency accuracy than the second configuration, and/or less phase noise than the second configuration, and/or lower noise emission level than the second configuration.

The method 600 comprises transmitting 630, to the WCD 110, an indication of the selected configuration of the transmitter circuitry 112. The indication transmitted at step 630 may for example include one or more parameters defining/identifying the selected configuration. For example, the transmitter circuitry 112 may include multiple components with different possible settings, and the transmission at step 630 may for example include one parameter for each of these components.

In some embodiments, an index with N>1 possible index values may be used to characterize the transmitter circuitry configurations selectable step 620. This index defines a mapping of transmitter circuitry configurations and is known to the network node 120 and the WCD 110, so that the selected configuration can be efficiently signaled at step 630 from the network node 120 to the WCD 110 via a single index value. This index setup (in other words, this mapping from index values to transmitter circuitry configurations) may for example be used if it is specified in a standard specification, or if the index setup is indicated by the network node 120 to the WCD 110 via broadcast signaling or dedicated signaling. Each of the index values n=1 ,2,..., N may for example correspond to a certain transmitter circuitry configuration, that is, a value range of one or more transmitter circuitry properties. For example, n=1 may correspond to the case where the noise emission level is below a certain threshold, and the power amplifier fulfills a certain linearity requirement, and oscillator accuracy is within a certain specified range. Similarly, n=2 may correspond to another set of values, and so on. In some embodiments, a single table of N possible index values may be used for selection and indication of the transmitter circuitry configuration with respect to multiple factors (such as energy minimization, El RP maximization, latency reduction, etc.). In some embodiments, multiple factors (such as energy minimization, EIRP maximization, latency reduction, etc.) may be defined and known to the network node 120 and the WCD 110, and different sets of transmitter circuitry configurations may be defined for different of these multiple factors. In some embodiments, the WCD 110 may report to the network node 120 which of the N index values (and thereby also the associated transmitter circuitry configurations) the WCD 110 is capable of supporting, and the selection at step 620 may be made among the supported values. The WCD 110 may for example also report/indicate one or more of the factors (such as energy minimization, El RP maximization, latency reduction, etc.) which it prefers to be optimized at the selection step 620. This information can for example be stored with other capabilities of the WCD 110 in the so- called UE context of the, and can be retrieved by the network node 120 before configuring the WCD 110.

In some embodiments, the indication transmitted at step 630 may be cell-specific and broadcast in system information, or it may be WCD-specific and transmitted via dedicated signaling.

In some embodiments, the network node 120 may indicate the transmitter circuitry configuration(s) to be used for optimizing a certain factor (such as energy minimization, EIRP maximization, latency reduction, etc.). For example, the network node 120 may indicate to the WCD 110 at step 630 to use a configuration n_1 if the WCD 110 strives to minimize energy consumption, and another configuration n_2 if the WCD 110 strives to achieve low latency, etc.

In some embodiments, the use of a certain configuration of the transmitter circuitry 112 may be determined based on the WCD’s coverage. For example, in poor coverage the WCD 110 may be allowed to use a configuration with more non-linear power amplification to increase the transmit power. Hence, the step 620 in the method 600 or the step 220 in the method 200 may take the WCD’s coverage condition into account when selecting a configuration for the processing circuitry 112.

If the transmitting step 630 in the method 600 provides a common configuration, to a plurality of WCDs, of the configuration of transmitter circuitry 112, then conditions for when which configuration should be applied by WCDs may be provided in system information broadcast. Alternatively, it could be indicated by the network node 120 when WCDs are allowed to apply certain configurations of the transmitter circuitry 112, and the WCDs could then select configuration of the transmitter circuitry 112 themselves (as in the method 200). For example, reference signal received power (RSRP) thresholds could be mapped to the transmitter circuitry configurations a WCD should, or is allowed to, use. That is, if a WCD’s measured RSRP is above a certain threshold, the WCD may conclude that its coverage is sufficient to use a certain transmitter circuitry configuration. This is exemplified in Fig. 7 (where ‘TCC’ refers to transmit chain configuration, which is an example of transmitter circuitry configuration) and the associated Table 1 below:

Table 1

If the transmitting step 630 in the method 600 provides WCD-dedicated configuration, the transmitter circuitry configuration a WCD shall apply could either be configuration via dedicated radio resource control (RRC) configuration, or indicated in DCI (for example by indicating the TCC index in Table 1 and in Fig. 7). If the WCD 110 does not have a valid transmitter circuitry configuration (for example, the WCD 110 is not able to use the configuration indicated by the network node 120, or the WCD 110 does not receive the indication transmitted at step 630), the WCD 110 may for example use a pre-defined configuration of the transmitter circuitry 112, typically a configuration corresponding to celledge performance. In some embodiments, only stationary WCDs may be configured with a transmitter circuitry configuration different from a configuration to be used at the cell-edge. Indeed, the network may want to avoid that mobile WCDs apply the wrong transmitter circuitry configuration, which may have a negative impact on network performance.

In some embodiments, the WCD 110 may transmit/signal information to the network node 120 regarding which transmitter circuitry configuration it supports and/or it desires to be configured with, optionally also accompanied by one or more measurements values or parameters relevant for the configuration. The selection at step 620 of a configuration to be used may for example be based also on such information from the WCD 110.

In some embodiments, rather than having N index values that characterize the possible configurations of the transmitter circuitry 112, the network node 120 may signal the requirements for the different adjustable features in the transmitter circuitry 112, so that the WCD 110 may select an appropriate configuration of the transmitter circuitry 112.

In some embodiments, the network node 120 may signal a delta vector, containing information about the changes that should or could be done by the WCD 110. As an example, the delta vector may contain information that the transmit power should be increased one step (for example by 1 dB), and that it is feasible to reduce the frequency accuracy one step (for example by 10%).

In some embodiments, where WCDs are performing the method 200 and selects configurations for their transmitter circuitry to optimize some factor (such as energy minimization, El RP maximization, latency reduction, etc.), the network (for example the network node 120) may schedule WCDs on the uplink to help the WCDs achieve their goals/targets. In a first example, the network node 110 may schedule cheap (or energy-limited) WCDs on lightly loaded bands/channels which may support relaxed requirements in terms of spectral characteristics or timing/frequency errors, etc. In a second example, when scheduling, the network (for example the network node 120) may distribute cheap (or energy-limited) WCDs across uplink time/frequency resources in order to avoid overwhelming a single uplink channel due to intrinsic interference from transmissions emanating from cheap WCDs (or from WCDs operating with relaxed interference requirements to save energy) etc. In a third example, good link quality in downlink and bad link quality in uplink may indicate that the network node 120 is experiencing interference on the uplink. This information can be used for scheduling WCDs on the uplink to facilitate transmitter circuitry adaption in combination with other information as mentioned in previous examples. For instance, to improve link quality in uplink, the network node 120 may indicate to the WCDs to make one or more of the following adjustments:

• Adjust modulation and coding schemed (MCS). Transmission with lower MCS increases the chance of successful reception.

• Adjust transmit power. Increasing the transmit power may improve chances of successful reception at the receiver because more signal power results in better signal to interference plus noise ratio in the intended receiver.

• Adjust frequency and/or bandwidth. Changing the carrier frequency and/or transmission bandwidth and/or changing the center of the frequency sub-band withing the frequency band may help reduce uplink interference and may improve the chance of successful reception.

In some embodiments, the method 600 may comprise receiving a transmission from the WCD 110, where the received transmission uses the selected configuration of the transmitter circuitry 112 of the WCD 110.

In some embodiments, the method 600 may comprise receiving an indication from the WCD 110 of a plurality of candidate configurations of transmitter circuitry. In such embodiments, the selection at step 620 of a configuration of the transmitter circuitry 112 of the WCD 110 may be made from among the candidate configurations. The candidate configurations may for example be configurations supported by the WCD 110 or configurations preferred by the WCD 110.

In some embodiments, the method 600 comprises transmitting an indication to the WCD 110 to adjust a transmit power, and/or a transmit frequency, and/or a transmit bandwidth, and/or a center of frequency of a sub-band within a frequency band, and/or a modulation and coding scheme (MCS). The method 600 may also comprise receiving a transmission from the WCD 110, where the received transmission uses the configuration selected at step 620 and is in accordance with the indicated adjustment. The indication to adjust may for example be transmitted to the WCD 110 in response to a detection that link quality in the downlink is relatively good while link quality in the uplink is relatively bad (because this may indicate that the network node 120 is experiencing interference on the uplink).

In some embodiments, the method 600 comprises receiving an indication of a level of energy of the WCD 110. At step 620, the configuration of the transmitter circuitry 112 of the WCD 110 may be selected based on the information obtained at step 610 and the level of energy of the WCD 110. The level of energy of the WCD 110 may for example be an energy level of a power source (such as a battery) at the WCD 110. The WCD 110 may for example indicate/signal its energy level to the network node 120.

In some embodiments, the method 600 comprises receiving an indication of an energy availability pattern of the WCD 110. At step 620, the configuration of the transmitter circuitry 112 of the WCD 110 may be selected based on the information obtained at step 610 and the energy availability pattern of the WCD 110. The WCD 110 may for example be configured to harvest energy from its environment, and it may be possible to predict when the WCD 110 will be able to harvest plenty of energy from the environment and when it is likely that energy will be scarce at the WCD 110.

In some embodiments, the method 600 may comprise receiving, from the WCD 110, an indication of a power level of a signal received at the WCD 110. In such embodiments, the selection at step 620 of the configuration of the transmitter circuitry of the WCD may be based on whether the power level of the signal received at the WCD 110 exceeds a threshold. That signal received at the WCD 110 may for example be a reference signal. That signal received at the WCD 110 may for example be transmitted by the network node 120. The power level may for example be a reference signal received power (RSRP) level. The power level of the received signal may for example be measured by the WCD 110. As described above in connection with reference to Fig. 7 and Table 1, a power level (such as a level of RSRP) of a received signal may indicate which configuration(s) of the transmitter circuitry 112 are suitable.

In some embodiments, the information obtained at step 610 indicates a quality of service (QoS) requirement. A service to be used by the WCD 110 may for example require a certain QoS level. The network node 110 may for example select a configuration of the transmitter circuitry 112 which is suitable for the QoS requirement.

Claims

1. A method (200) at a wireless communication device (110), WCD, the method comprising: receiving (210) information from a network node (120), the received information indicating a status of an uplink channel; selecting (220), based on the received information, a configuration of transmitter circuitry (112) of the WCD; and transmitting (230) to the network node using the selected configuration of the transmitter circuitry.

2. The method of claim 1, wherein selecting a configuration of the transmitter circuitry comprises: selecting between using different components (501, 502) of the transmitter circuitry; or selecting whether to inactivate at least one component of the transmitter circuitry; or selecting between using different settings of at least one component of the transmitter circuitry.

3. The method of any of the preceding claims, wherein selecting a configuration of the transmitter circuitry comprises selecting a configuration of: frequency generation circuitry (401); or a power amplifier (402); or linearization circuitry (403); or a digital to analog converter (404); or reconstruction filtering (405) located after a digital to analog converter.

4. The method of any of the preceding claims, wherein selecting a configuration of the transmitter circuitry comprises: selecting between a phase locked loop, PLL, and a free-running oscillator; or selecting whether to inactivate a PLL.

5. The method of any of the preceding claims, wherein selecting a configuration of the transmitter circuitry comprises: selecting between at least a first configuration and a second configuration, wherein the second configuration is associated with lower energy consumption than the first configuration.

6. The method of any of claims 1-4, wherein selecting a configuration of the transmitter circuitry comprises: selecting between at least a first configuration and a second configuration, wherein, for a certain level of energy consumption, the second configuration is associated with: higher effective isotropic radiated power than the first configuration; or lower block error rate than the first configuration; or higher throughput than the first configuration; or lower false alarm rate than the first configuration; or higher miss detection rate than the first configuration; or lower interference caused than the first configuration; or higher effective uplink signal to interference and noise ratio, SI NR, than the first configuration.

7. The method of claim 6 or 7, wherein the first configuration is associated with: higher degree of linearity than the second configuration; or higher frequency accuracy than the second configuration; or less phase noise than the second configuration; or lower noise emission levels than the second configuration.

8. The method of any of the preceding claims, wherein the status of the uplink channel comprises: an uplink channel quality; or an interference level on the uplink; or a network load; or a tolerable frequency error level on the uplink; or a tolerable timing error level on the uplink; or a tolerable phase noise level on the uplink; or a tolerable error vector magnitude, EVM.

9. The method of any of the preceding claims, wherein the received information represents at least: a measurement value; or an estimated channel condition.

10. The method of any of the preceding claims, wherein the configuration of the transmitter circuitry is selected based on the received information and a level of energy available at the WCD.

11. The method of any of the preceding claims, wherein the configuration of the transmitter circuitry is selected based on the received information and an energy availability pattern of the WCD.

12. The method of any of the preceding claims, wherein the WCD is configured to harvest energy from its environment.

13. The method of any of the preceding claims, further comprising: receiving an indication of a plurality of candidate configurations of transmitter circuitry, wherein the selection of the configuration of the transmitter circuitry of the WCD is made from among the plurality of candidate configurations of transmitter circuitry.

14. The method of any of the preceding claims, wherein the configuration of the transmitter circuitry of the WCD is selected based on the received information and a power level of a signal received at the WCD.

15. The method of claim 14, further comprising: receiving an indication of a threshold, wherein the selection of the configuration of the transmitter circuitry of the WCD is based on whether the power level of the signal received at the WCD exceeds the threshold.

16. The method of any of the preceding claims, wherein the received information also indicates a quality of service, QoS, requirement.

17. The method of any of the preceding claims, further comprising receiving an indication from the network node to adjust: a transmit power; or a transmit frequency; or a transmit bandwidth; or a center of frequency of a sub-band within a frequency band; or a modulation and coding scheme, MCS, wherein the transmitting to the network node is performed in accordance with the indicated adjustment.

18. A wireless communication device (110), WCD, comprising transmitter circuitry (112), wherein the wireless device is configured to: receive information from a network node (120), the received information indicating a status of an uplink channel; select, based on the received information, a configuration of transmitter circuitry of the WCD; and transmit to the network node using the selected configuration of the transmitter circuitry.

19. The wireless device of claim 18, configured to perform the method of any of claims 2-17.

20. A method (300) at a network node (120), the method comprising: obtaining (310) information indicating a status of an uplink channel; transmitting (320) the information to a wireless communication device (110), WCD, for the WCD to select a configuration of transmitter circuitry (112) of the WCD based on the information; and receiving (330) a transmission from the WCD.

21. The method of claim 20, wherein the received transmission uses the selected configuration of the transmitter circuitry of the WCD.

22. The method of any of claims 20-21, wherein obtaining information indicating a status of an uplink channel comprises: performing a measurement.

23. The method of any of claims 20-21, wherein obtaining information indicating a status of an uplink channel comprises: receiving an indication of the status of the uplink channel.

24. The method of any of claims 20-23, wherein the status of the uplink channel comprises: an uplink channel quality; or an interference level on the uplink; or a network load; or a tolerable frequency error level on the uplink; or a tolerable timing error level on the uplink; or a tolerable phase noise level on the uplink; or a tolerable error vector magnitude, EVM.

25. The method of any claims 20-24, wherein the transmitted information represents at least: a measurement value; or an estimated channel condition.

26. The method of any of claims 20-25, further comprising: transmitting, to the WCD, an indication of a plurality of candidate configurations of transmitter circuitry from which the WCD is to select to the configuration of transmitter circuitry of the WCD.

27. The method of claim 26, further comprising: receiving an indication of a level of energy of the WCD; and selecting the plurality of candidate configurations of transmitter circuitry based on the level of energy of the WCD.

28. The method of claim 26 or 27, further comprising: receiving an indication of energy availability pattern of the WCD; and selecting the plurality of candidate configurations of transmitter circuitry based on the energy availability pattern of the WCD.

29. The method of any claims 20-28, wherein the WCD is configured to harvest energy from its environment.

30. The method of any of claims 20-29, further comprising: transmitting an indication of a threshold for the WCD to apply for a power level of a received signal when selecting the configuration of the transmitter circuitry of the WCD.

31. The method of claims 20-30, wherein the transmitted information also indicates a quality of service, QoS, requirement.

32. The method of any of claims 20-31 , further comprising transmitting an indication to the WCD to adjust: a transmit power; or a transmit frequency; or a transmit bandwidth; or a center of frequency of a sub-band within a frequency band; or a modulation and coding scheme, MCS, wherein the received transmission is in accordance with the indicated adjustment.

33. The method of claim 32, wherein the indication to adjust is transmitted to the WCD in response to a detection that link quality in the downlink is relatively good while link quality in the uplink is relatively bad.

34. A network node (120) configured to: obtain information indicating a status of an uplink channel; transmit the information to a wireless communication device (110), WCD, for the WCD to select a configuration of transmitter circuitry (112) of the WCD based on the information; and receive a transmission from the WCD.

35. The network node of claim 34, configured to perform the method of any of claims 21-33.

36. A method (600) at a network node (120), the method comprising: obtaining (610) information indicating a status of an uplink channel, wherein obtaining the information comprises performing a measurement or estimating a channel condition; selecting (620), based on the obtained information, a configuration of transmitter circuitry (112) of a wireless communication device (110), WCD; and transmitting (630), to the WCD, an indication of the selected configuration of the transmitter circuitry.

37. The method of claim 36, further comprising: receiving a transmission from the WCD, wherein the received transmission uses the selected configuration of the transmitter circuitry of the WCD.

38. The method of any of claims 36-37, wherein selecting a configuration of the transmitter circuitry comprises: selecting between different components (501, 502) of the transmitter circuitry; or selecting whether at least one component of the transmitter circuitry is to be inactivated; or selecting between different settings of at least one component of the transmitter circuitry.

39. The method of any of claims 36-38, wherein selecting a configuration of the transmitter circuitry comprises selecting a configuration of: frequency generation circuitry (401); or a power amplifier (402); or linearization circuitry (403); or a digital to analog converter (404); or reconstruction filtering (405) located after a digital to analog converter.

40. The method of any of claims 36-39, wherein selecting a configuration of the transmitter circuitry comprises: selecting between a phase locked loop, PLL, and a free-running oscillator; or selecting whether a PLL is to be inactivated.

41. The method of any of claims 36-40, wherein selecting a configuration of the transmitter circuitry comprises: selecting between at least a first configuration and a second configuration, wherein the second configuration is associated with lower energy consumption than the first configuration.

42. The method of any claims 36-40, wherein selecting a configuration of the transmitter circuitry comprises: selecting between at least a first configuration and a second configuration, wherein, for a certain level of energy consumption, the second configuration is associated with: higher effective isotropic radiated power than the first configuration; or lower block error rate than the first configuration; or higher throughput than the first configuration; or lower false alarm rate than the first configuration; or higher miss detection rate than the first configuration; or lower interference caused than the first configuration; or higher effective uplink signal to interference and noise ratio, SINR, than the first configuration.

43. The method of claim 41 or 42, wherein the first configuration is associated with: higher degree of linearity than the second configuration; or higher frequency accuracy than the second configuration; or less phase noise than the second configuration; or lower noise emission levels than the second configuration.

44. The method of any of claims 36-43, further comprising: receiving an indication from the WCD of a plurality of candidate configurations of transmitter circuitry, wherein the selection of a configuration of the transmitter circuitry of the WCD is made from the candidate configurations.

45. The method of claim 44, wherein the candidate configurations are configurations supported by the WCD or configurations preferred by the WCD.

46. The method of any of claims 36-45, wherein the status of the uplink channel comprises: an uplink channel quality; or an interference level on the uplink; or a network load; or a tolerable frequency error level on the uplink; or a tolerable timing error level on the uplink; or a tolerable phase noise level on the uplink; or a tolerable error vector magnitude, EVM.

47. The method of any of claims 36-46, comprising: transmitting an indication to the WCD to adjust: a transmit power; or a transmit frequency; or a transmit bandwidth; or a center of frequency of a sub-band within a frequency band; or a modulation and coding scheme, MCS; and receiving a transmission from the WCD, wherein the received transmission uses the selected configuration of the transmitter circuitry of the WCD and is in accordance with the indicated adjustment.

48. The method of claim 47, wherein the indication to adjust is transmitted to the WCD in response to a detection that link quality in the downlink is relatively good while link quality in the uplink is relatively bad.

49. The method of any of claims 36-48, further comprising: receiving an indication of a level of energy of the WCD, wherein the configuration of the transmitter circuitry of the WCD is selected based on the obtained information and the level of energy of the WCD.

50. The method of any of claims 36-49, further comprising: receiving an indication of energy availability pattern of the WCD, wherein the configuration of the transmitter circuitry of the WCD is selected based on the obtained information and the energy availability pattern of the WCD.

51. The method of any of claims 36-50, wherein the WCD is configured to harvest energy from its environment.

52. The method of any of claims 36-51 , further comprising: receiving, from the WCD, an indication of a power level of a signal received at the WCD, wherein the selection of the configuration of the transmitter circuitry of the WCD is based on whether the power level of the signal received at the WCD exceeds a threshold.

53. The method of any of claims 36-52, wherein the obtained information also indicates a quality of service, QoS, requirement.

54. A network node (120) configured to: obtain information indicating a status of an uplink channel, wherein obtaining the information comprises performing a measurement or estimating a channel condition; select, based on the obtained information, a configuration of transmitter circuitry (112) of a wireless communication device (110), WCD; and transmit, to the WCD, an indication of the selected configuration of the transmitter circuitry.

55. The network node of claim 54, configured to perform the method of any of claims 37-53.