CN115051764B - System and method for monitoring quality condition of transmission channel of WLAN 11ax system - Google Patents
System and method for monitoring quality condition of transmission channel of WLAN 11ax system Download PDFInfo
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- CN115051764B CN115051764B CN202210625631.7A CN202210625631A CN115051764B CN 115051764 B CN115051764 B CN 115051764B CN 202210625631 A CN202210625631 A CN 202210625631A CN 115051764 B CN115051764 B CN 115051764B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/10—Monitoring; Testing of transmitters
- H04B17/15—Performance testing
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/10—Monitoring; Testing of transmitters
- H04B17/11—Monitoring; Testing of transmitters for calibration
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/30—Monitoring; Testing of propagation channels
- H04B17/309—Measuring or estimating channel quality parameters
- H04B17/318—Received signal strength
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W84/00—Network topologies
- H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
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Abstract
The present application provides a system for monitoring transmit channel quality conditions for a WLAN 11ax system, the system including a transmitter and a processor. The transmitter transmits at least one detection signal in a symbol corresponding to PE of the PPDU through a transmission channel of the WLAN 11ax system. The processor is configured to collect a feedback signal associated with the PPDU using a feedback channel and to obtain a quality condition of the transmit channel based on data associated with the at least one sounding signal in the feedback signal. By utilizing the system provided by the application, the dynamic monitoring of the quality condition of the transmitting channel can be realized through the monitoring of the distortion condition of the transmitting signal.
Description
Technical Field
The present application relates to the field of wireless communication technology, and more particularly, to a system and method for monitoring the quality condition of a transmission channel of a WLAN 11ax system.
Background
The actual parameters and characteristics of the rf device will vary with temperature, aging, impedance, power supply, etc., and many times when these parameters have changed. If the calibration parameters do not follow the changes, the quality of the sent signal is poor, and other users on the air interface can be interfered, so that the throughput of the system is reduced. Therefore, monitoring the quality of the transmitted RF signal is necessary.
It is common practice to restart the calibration once periodically, but this is likely to be corrected again after the distortion has occurred for a long time. One is to demodulate the signal emitted from the radio frequency Power Amplifier (PA) by introducing it into its own receiving path via the feeder line, and extract the Error Vector Magnitude (EVM), etc., but this is costly to implement.
Disclosure of Invention
The present application has been made in view of the above-mentioned technical problems occurring in the prior art. The application aims to provide a system for monitoring the quality condition of a transmitting channel of a WLAN 11ax system, which can rapidly monitor various parameters of a transmitting radio frequency signal with low cost on the basis of adhering to a WLAN 11ax protocol, rapidly feed back the parameters to a feedback end and remind of updating corresponding calibration.
According to a first aspect of the present application there is provided a system for monitoring transmit channel quality conditions for a WLAN 11ax system, the system comprising a transmitter and a processor. Wherein the transmitter is configured to transmit at least one probing signal in a symbol corresponding to a PE of a PPDU via a transmission channel of the WLAN 11ax system. The processor is configured to collect a feedback signal associated with the PPDU using a feedback channel and to obtain a quality condition of the transmit channel based on data associated with the at least one sounding signal in the feedback signal.
According to a second aspect of the present application there is provided a method for quality condition monitoring of a transmission channel of a WLAN 11ax system, the method comprising transmitting at least one probe signal within a symbol corresponding to a PE of a PPDU via the transmission channel of the WLAN 11ax system based on a transmitter, and based on a processor, utilizing a feedback channel to collect a feedback signal associated with the PPDU and based on data associated with the at least one probe signal in the feedback signal, obtaining a quality condition of the transmission channel.
According to a third aspect of the present application there is provided a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, cause the processor to perform a method for WLAN 11ax system transmit channel quality condition monitoring according to various embodiments of the present application.
Compared with the prior art, the embodiment of the application has the beneficial effects that:
based on the WLAN 11ax protocol, at least one probe signal is transmitted in a symbol corresponding to the PE of the PPDU, and in response to the probe signal, the system generates a feedback signal corresponding to the probe signal. Based on the data associated with at least one detection signal in the feedback signal, such as signal strength, the quality condition of the transmitting channel is judged by comparing the signal strength, and corresponding calibration is performed. According to the system and the method provided by the embodiment of the application, on the basis of adhering to the WLAN 11ax protocol framework, on the premise of not causing unexpected interference to the existing protocol and signals, various parameters related to the radio frequency transmission signal are conveniently measured at low cost, so that the real-time dynamic monitoring of the quality condition of the radio frequency transmission channel is realized.
The foregoing general description and the following detailed description are exemplary and explanatory only and are not intended to limit the claimed application.
Drawings
In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like reference numerals with letter suffixes or different letter suffixes may represent different examples of similar components. The drawings illustrate generally, by way of example, and not by way of limitation, various embodiments, and together with the description and claims serve to explain the disclosed embodiments. Such embodiments are illustrative and exemplary, and are not intended to be exhaustive or exclusive embodiments of the present methods, apparatus, systems, or non-transitory computer readable media having instructions for implementing the methods.
FIG. 1 shows a schematic block diagram of a system for WLAN 11ax system transmit channel quality condition monitoring in accordance with an embodiment of the present application;
fig. 2 is a block diagram showing a wireless transceiver system based on a WLAN 11ax according to an embodiment of the present application;
FIG. 3 shows a spectral diagram of a change in circuit characteristics of a transmit mixer due to IQ mismatch in accordance with an embodiment of the present application;
FIG. 4 shows a spectrum diagram of a power amplifier with varying nonlinear characteristics according to an embodiment of the application;
FIG. 5 is a graph showing a frequency spectrum when compensation of original frequency dependent IQ mismatch due to circuit parameter variations is not good enough to compensate for current FDIQ in accordance with an embodiment of the present application;
FIG. 6 shows a spectrum graph of a drop in output power due to a power amplifier according to an embodiment of the application;
fig. 7 shows a flow chart of a method for quality condition monitoring of a transmit channel of a WLAN 11ax system in accordance with an embodiment of the application.
Detailed Description
The present application will be described in detail below with reference to the drawings and detailed description to enable those skilled in the art to better understand the technical scheme of the present application. Embodiments of the present application will be described in further detail below with reference to the drawings and specific examples, but not by way of limitation.
The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises" and the like means that elements preceding the word encompass the elements recited after the word, and not exclude the possibility of also encompassing other elements. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
In the present application, when it is described that a specific device is located between a first component and a second component, an intervening device may or may not be present between the specific device and the first device or the second device. When it is described that a specific device is connected to another device, the specific device may be directly connected to the other device without an intervening device, or may be directly connected to the other device without an intervening device. In the present application, the arrows shown in the figures of the respective steps are merely examples of the execution sequence, and the technical solution of the present application is not limited to the execution sequence described in the embodiments, and the respective steps in the execution sequence may be performed in combination, may be performed in decomposition, and may be exchanged as long as the logical relationship of the execution contents is not affected.
All terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs, unless specifically defined otherwise. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.
The system according to the embodiment of the application is suitable for a wireless transceiver system under the framework of the WLAN 11ax protocol.
The system for monitoring the quality condition of the transmission channel of the WLAN 11ax system according to the embodiment of the application can be realized by improving part of functions on the basis of the existing WLAN 11ax system. A system for monitoring the quality condition of a transmission channel of a WLAN 11ax system according to an embodiment of the present application will be described in detail with reference to fig. 1 and 2.
Fig. 1 is a schematic block diagram of a system for monitoring a quality condition of a transmission channel of a WLAN 11ax system according to an embodiment of the present application, and fig. 2 is a block diagram of a wireless transceiver system based on the WLAN 11ax system according to an embodiment of the present application. As shown in fig. 1, a system 100 for monitoring transmit channel quality conditions for a WLAN 11ax system in accordance with an embodiment of the application may include, for example, a transmitter 101 and a processor 102. Wherein the processor 102 may be a processing device, such as a microprocessor, a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), or the like, which may include one or more general purpose processing devices. More specifically, the processor 102 may be a Complex Instruction Set Computing (CISC) microprocessor, a Reduced Instruction Set Computing (RISC) microprocessor, a Very Long Instruction Word (VLIW) microprocessor, a processor executing other instruction sets, or a processor executing a combination of instruction sets. The processor 102 may also be one or more special purpose processing devices, such as an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP), a system on a chip (SoC), or the like. As will be appreciated by those skilled in the art, in some embodiments, the processor 102 may be a special purpose processor rather than a general purpose processor. Processor 102 may include one or more known processing devices such as microprocessors from the Pentium, core, xeon, or Itanium families manufactured by Intel, turion, athlon, sempron, opteron, FX, phenom families manufactured by AMD, or various processors manufactured by Sun Microsystems. Processor 102 may also include a graphics processing unit, such as from Is manufactured by Nvidia TM +.> Series, GMA manufactured by Intel, iris, or Radeon, manufactured by AMD. The processor 102 may also include an acceleration processing unit, such as the Desktop A-4 (6, 6) family manufactured by AMD (TM), the Xeon Phi (TM) family manufactured by Intel (TM). In addition, the term "processor" or "image processor" may include more than one processor, for example, a multi-core design or a plurality of processors, each having a multi-core design. Processor 102 may execute sequences of computer program instructions stored in memory to perform the various operations, processes, and methods disclosed herein.
Fig. 2 illustrates a block diagram of a WLAN 11 ax-based transceiver system, and as shown in fig. 2, a WLAN 11 ax-based transceiver system 200 may include a transmit channel 201 and a feedback channel 209, in accordance with an embodiment of the present application. The transmit channel 201 may in turn include a baseband transmission 201a, a DAC (digital to analog converter) 202, a first ALPF (analog baseband low pass filter) 203, a transmit mixer (Tx mixer) 204, a PA (power amplifier) 205, and a transmit antenna 205'. The feedback path 209 may in turn include a signal coupler (radio frequency signal coupler) 206', a receive mixer (Rx mixer) 206, a second ALPF 207, an ADC (analog to digital converter) 208, and a baseband receive and process 209a. The baseband transmission 201a may integrate the functions of the transmitter 101 shown in fig. 1 according to the embodiment of the present application based on the original baseband transmission function based on the WLAN 11ax protocol, that is, the baseband signal output by the baseband transmission 201a includes at least one detection signal in the symbol corresponding to the PE of the PPDU. In other embodiments, the original WLAN 11ax baseband transmission function may be integrated by the transmitter 101 instead, which is not limited by the present application.
As shown in fig. 2, a digital baseband signal transmitted by transmitter 101 (via baseband transmission 201 a) is converted to an analog baseband signal by DAC 202, then passed through an analog baseband low pass filter, first ALPF 203 (which may be a Butterworth filter, for example), filtered out of band interference and noise, and then passed through transmit mixer 204 to shift the signal to radio frequency, then input to power amplifier PA 205, and transmitted.
At the signal feedback end (not shown), the signal receiving process is the inverse process described above, and the signal received from the antenna is sent to the receiving mixer 206 through the band-pass filter (not shown), so that the signal is shifted to the baseband or low intermediate frequency, filtered out of band signal and noise through the analog baseband filter (not shown), and converted to the digital baseband through the analog-to-digital converter (ADC 208), and then subjected to corresponding digital processing.
In some embodiments, the feedback channel 209 shown in fig. 2 may be used as an analog for performing a signal receiving process on the signal feedback end, specifically, the transmitting signal output by the PA 205 may be coupled to the feedback channel 209 through the signal coupler 206', and mixed sequentially by the receiving mixer 206, the second ALPF 207 is low-pass filtered, and after the ADC 208 is converted into a digital signal, the baseband receiving and processing 209a performs the original operations of the system such as signal demodulation, and performs various functions and operations of the processor 102 shown in fig. 1 according to an embodiment of the present application. Hereinafter, the original functions of the respective components in the transmit channel 201 and the feedback channel 209 will not be described again, and specific functions and configurations of the transmitter 101 and the processor 102 in the system for monitoring the quality condition of the transmit channel 201 in the WLAN 11ax system (i.e., the wireless transceiver system 200 based on the WLAN 11 ax) according to the embodiment of the present application will be described.
The transmitter 101 may be, for example, a router. For example, the router may perform the transmission of at least one probe signal within a symbol corresponding to the PE of the PPDU via a transmission channel of said WLAN 11ax system.
WIFI6 (WLAN 11 ax), taking into account the difference in processing power for different STAs (stations), protocol introduction PE (Packet Extension), i.e. introducing time domain waveforms of {0us,4us,8us,12us,16us } length at the end of each PPDU (Presentation Protocol Data Unit, protocol data unit), in order to reserve sufficient data processing time for the feedback end. The requirement for this waveform of the PE is that the power is the same as the power of the preceding data portion so that its spectrum does not produce out-of-band leakage, while the specific content transmitted is not required. PPDUs are formats that represent layer packets in OSI, and the leftmost fields in the PPDU packet structure are sent and received preferentially. In fields of multiple bytes, the least significant byte is sent or received preferentially, while in each byte the Least Significant Bit (LSB) is sent preferentially, as is the transfer of data fields between the presentation layer and the MAC layer.
The detection signal may be a single frequency complex sinusoidal signal (also referred to as a single frequency tone), or other spectrally simpler signal. Based on the WLAN 11ax protocol, the transmitter 101 sends one or more probing signals in the symbol corresponding to the PE of the PPDU, where the probing signals are used to monitor the quality status of the transmission channel by measuring the transmission signals. The transmitter 101 schedules transmission of the probe signal based on the link condition, for example, the transmitter 101 may transmit the probe signal at regular intervals, or may determine a specific timing for transmitting the probe signal based on a specific quality condition of the transmission channel after acquiring the quality condition of the entire transmission channel, or transmit the probe signal in other possible manners, which is not limited in detail in the present application. Because the sending time and the sending mode of the detection signal are in the WLAN 11ax protocol frame, extra time is not required to be occupied for sending nonstandard signals and the like, adverse effects such as interference and the like on a normal running protocol and network communication are avoided, and real-time monitoring of the quality condition of a transmitting channel can be realized at low cost.
In some embodiments, the processor 102 may be configured to collect feedback signals associated with the PPDU using a feedback channel and to obtain a quality condition of the transmit channel based on data associated with the at least one sounding signal in the feedback signals. In response to the probe signal transmitted by the transmitter 101, feedback information corresponding to the probe signal will appear in the frequency spectrum, e.g. the feedback information may be mirror information, feedback information at different frequency positions, third order intermodulation information or other response information, etc. In some embodiments, the manner in which the sounding signal is transmitted in the PPDU may be selected based on the particular parameters of the transmission channel that are intended to be monitored, and monitoring of the quality condition of the transmission channel corresponding to the particular parameters may be achieved by measurement of the associated feedback signal. For example, when the non-linear characteristics of the power amplifier PA205 change, distortion may occur in the transmit signal, and in response to the distortion, significant third-order intermodulation of strength may occur in the feedback signal associated with the PPDU. At this time, it may be determined whether the link needs to be calibrated for the nonlinear characteristic of the power amplifier PA205 based on the data associated with the at least one probe signal in the feedback signal, such as the strength of the third-order intermodulation signal in the above embodiment, and the parameter for calibrating the link may be determined by comparing the degree of the above strength change (e.g., from a preset normal value, etc.).
In some embodiments, IQ mismatch (IQ mismatch) may result when the IQ two mixed carrier signals on the transmit channel 201 are no longer exactly matched. IQ mismatch may include, for example, frequency independent IQ mismatch (or frequency-flat IQ mismatch) and frequency dependent IQ mismatch (or frequency selective IQ mismatch, frequency dependent). Wherein the frequency independent IQ mismatch is caused by non-ideal phase deviations (phase deviations of not exactly 90 degrees) and non-matching amplitude gains (gains not exactly equal) of the IQ branches in the local oscillators (Local Oscilllator, LO) of the transmitter, receiver. The IQ mismatch parameters are not related to frequency, i.e. the IQ mismatch effects suffered by each subcarrier in the OFDM symbol are the same. For example, if the IQ two carriers of the transmit mixer 204 in fig. 2 are not exactly orthogonal, then frequency-independent IQ mismatch and DC components (particularly carrier components leaking from the LO to the source) are introduced into the rf signal output therefrom, the former generating an image signal, and the latter generating additional carrier power. When there is a mismatch between the other devices of the in-phase and quadrature branches (e.g., first ALPF203, DAC 202, etc.), then a frequency dependent IQ mismatch is generated. In addition, the Digital Predistorter (DPD) used for power amplifier PA 205 nonlinear correction may also be distorted, especially for peak-to-average ratio (PAPR) signals, which is particularly noticeable. However, the present inventors found that these parameters and distortions associated with the quality condition of the transmit channel are estimated and compensated during the initial calibration phase of link establishment, and remain unchanged during the subsequent data transmission process, and are not adjusted, however, as the working environment changes, the device ages, the power supply changes, and other factors, the calibrated radio frequency parameters also change accordingly, resulting in deviations from the desired parameters, and the quality condition of the transmit channel cannot be accurately estimated, which may affect the quality of the data transmission in the link. Thus, embodiments according to the present application will detect the above-mentioned frequency independent/frequency dependent IQ mismatch, DC offset, DPD mismatch, FDIQ mismatch, output power calibration and other non-linearities and mismatches, and prompt the feedback end to perform calibration and compensation again. Specifically, in the embodiment of the present application, at least one sounding signal is sent in a symbol corresponding to a PE of the PPDU, and the processor 102 acquires a feedback signal responsive to the sounding signal by using the feedback channel 209, and acquires a quality condition of the transmitting channel 201 by comparing intensities of related spectrums in the feedback signal. The processor 102 sends the obtained quality status of the transmitting channel 201 to a feedback end (not shown) of the WLAN 11ax system, and the feedback end calibrates a link of the WLAN 11ax system based on the quality status of the transmitting channel 201, so as to dynamically monitor the transmitting channel 201 of the wireless transceiver system 200, so that the feedback end calibrates corresponding components and parameters thereof in the transmitting channel 201 according to the received quality status, thereby ensuring that the transmitting signal is accurate and undistorted, and improving the data transmission quality and transmission efficiency of the wireless transceiver system 200.
In some embodiments, the at least one probing signal includes a single tone or a plurality of single tones of different frequencies, so as to obtain a feedback signal in the frequency spectrum, which can obviously reflect the quality condition of the transmission channel 201. Acquiring the quality condition of the transmitting channel 201 based on the data associated with the at least one probe signal in the feedback signal, so that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmitting channel specifically includes acquiring the quality condition of the transmitting channel 201 based on the spectrum data associated with the one tone or multiple tones of different frequencies in the feedback signal, so that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmitting channel. In this way, the accuracy in dynamically monitoring the quality condition of the transmitting channel 201 is improved, so that the feedback end of the WLAN 11ax system can adjust the relevant parameters of the WLAN 11ax system to realize the calibration of the link. Methods of determination regarding quality conditions in particular include, but are not limited to, the following.
In some embodiments, the quality status of the transmitting channel 201 includes IQ mismatch, and based on spectral data associated with the single tone or multiple single tones of different frequencies in the feedback signal, obtaining the quality status of the transmitting channel, so that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality status of the transmitting channel specifically includes, by the processor 102, re-performing IQ calibration on the WLAN 11ax system when it is determined that a deviation of a signal strength at a mirror frequency of a first single tone in the at least one probe signal with respect to a signal strength of the first single tone is greater than a first threshold. Specifically, to send one f in the symbol corresponding to PE 0 For example, as shown in fig. 3, according to the embodiment of the present application, the spectrum diagram of the change of the circuit characteristics of the transmitting mixer due to IQ mismatch is shown, and the internal frequency is f in the PE 0 Is a single frequency point complex sine signal, and generates a frequency of-f in a corresponding frequency spectrum 0 This may be due to variations in the IQ mismatch characteristics of the transmit mixer 204, to which the original IQ mismatch compensation on the transmit path is not matched well enough. Processor 102 obtains the frequency at image frequency-f by analyzing the spectrum of baseband reception and processing 209a 0 Signal strength at and at f 0 Signal intensity at the mirror and obtain the signal intensity at the mirrorImage frequency-f 0 Signal strength at and at f 0 The ratio of the signal strengths at that point, if the ratio is above a first threshold, indicates that IQ calibration is required. The first threshold may be set manually, or may be set already at the time of shipment, and is not particularly limited. For example, when the first threshold is 0.001, if the ratio is higher than 0.001, the controller is prompted to perform IQ calibration.
In some implementations, the quality condition of the transmit channel 201 further includes a DC bias, and the acquiring the quality condition of the transmit channel 201 based on spectral data associated with the one tone or the plurality of tones of different frequencies in the feedback signal, such that the feedback end of the WLAN11ax system calibrates the link of the WLAN11ax system based on the quality condition of the transmit channel specifically includes, by the processor 102, re-calibrating the WLAN11ax system if it is determined that the at least one probe signal includes one tone, and if a deviation of a DC signal strength at a zero frequency from a signal strength of the tone is greater than a second threshold, causing the feedback end of the WLAN11ax system to DC calibrate the WLAN11ax system. Specifically, to send one f in the symbol corresponding to PE 0 For example, as shown in fig. 3, the internal frequency of the symbol corresponding to PE is f 0 A significant tone signal is seen at zero frequency DC across the frequency spectrum, which may be due to variations in the circuit characteristics of the transmit mixer 204, with which the original originating DC compensation does not match well enough. Processor 102 obtains signal strength at zero frequency and signal strength at f by analyzing the spectrum of baseband reception and processing 209a 0 Signal strength at zero frequency and signal strength at f 0 The ratio of the signal strengths at that point, if the ratio is above a second threshold, indicates that a DC calibration is required. The second threshold may be set manually, or may be set already at the time of shipment, and is not particularly limited. For example, when the second threshold is 0.001, if the ratio is higher than 0.001, the feedback terminal is prompted to perform DC calibration.
In some implementations, the quality condition of the transmit channel 201 includes DThe PD mismatch, based on spectrum data associated with the single tones of the multiple different frequencies in the feedback signal, obtains a quality condition of the transmitting channel 201, so that the feedback end of the WLAN11ax system calibrates a link of the WLAN11ax system based on the quality condition of the transmitting channel specifically includes, when the processor 102 determines that the at least one probe signal includes at least two single tones, and a deviation of a representative value of third-order intermodulation signal strength between the at least two single tones relative to a representative value of signal strength of the at least two single tones is greater than a third threshold, causing the feedback end of the WLAN11ax system to re-calibrate the WLAN11ax system. Specifically, taking two single frequency tones transmitted in the symbol corresponding to the PE as an example, as shown in a spectrogram of fig. 4 when the nonlinear characteristics of the power amplifier are changed according to an embodiment of the present application, the two single frequency tones are transmitted in the symbol corresponding to the PE 1 、f 2 A single tone at frequency responsive to the frequency at f 1 、f 2 A single tone at frequency, generating third order intermodulation (IM 3) in the feedback signal, the third order intermodulation IM3 being respectively at 2f 1 -f 2 Frequency and 2f 2 -f 1 This may be the case at frequency due to the non-linear nature of the power amplifier PA 205 changing, with which the original Digital Predistorter (DPD) cannot match well enough. Processor 102 obtains the spectrum at 2f by analyzing the baseband received and processed 209a spectrum 1 -f 2 At a frequency or at 2f 2 -f 1 Signal strength at frequency and at f 2 Or f 1 Signal strength at frequency and obtain at 2f 1 -f 2 Frequency and 2f 2 -f 1 Signal at frequency and f 1 And f 2 Ratio of signal intensities at. If the ratio is above the third threshold, it indicates that DPD calibration is required. The third threshold may be set manually, or may be set already at the time of shipment, and is not particularly limited. For example, when the third threshold is 0.002, if the ratio is higher than 0.002, the feedback end is prompted to perform DPD calibration.
In some implementations, when the mass of the emission channel 201The quality condition includes FDIQ (frequency dependent IQ mismatch) mismatch, and based on spectral data associated with the single tone or multiple single tones of different frequencies in the feedback signal, obtaining the quality condition of the transmit channel 201, so that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel specifically includes, when the processor 102 determines that the at least one probe signal includes more than two single tones, and when a deviation of a maximum value relative to a minimum value in each signal intensity of each single tone in the at least one probe signal at a respective image frequency is greater than a fourth threshold, causing the feedback end of the WLAN 11ax system to perform FDIQ calibration on the WLAN 11ax system. Specifically, taking four tones sent in the symbol corresponding to the PE as an example, as shown in fig. 5, the internal sending frequency of the symbol corresponding to the PE is f 0 、f 1 、f 2 、f 3 Is a single-frequency point complex signal) at the mirror frequency position of each of the four single-frequency tones, namely-f 0 、-f 1 、-f 2 、-f 3 With a corresponding feedback signal at the frequency. This may be the case because the original frequency dependent IQ mismatch (frequency dependent IQ mismatch) compensation is not sufficiently good to compensate for the current FDIQ due to circuit parameter variations. Processor 102 obtains the spectrum at-f by analyzing the baseband received and processed 209a spectrum 3 The intensity of the signal at frequency and at-f 0 The ratio of the intensities of the signals at the frequencies, if higher than a fourth threshold, indicates that FDIQ calibration is required. The fourth threshold may be set manually, or may be set already at the time of shipment, and is not particularly limited. For example, when the fourth threshold is 0.002, if the ratio is higher than 0.002, the feedback end is prompted to perform FDIQ calibration.
In some implementations, when the quality condition of the transmit channel 201 includes PA output power variation, the quality condition of the transmit channel is obtained based on spectral data associated with the one tone in the feedback signal, such that the feedback end of the WLAN 11ax system is configured to determine the quality of the transmit channel based on the quality condition of the transmit channel The calibration of the link of the 11ax system specifically includes that when the processor 102 judges that the at least one detection signal includes a single frequency tone, acquiring initial power of the single frequency tone in an initial calibration stage and detection power of the single frequency tone in a detection stage, where the initial power and the detection power are located at the same frequency, and when a deviation between the detection power and the initial power is smaller than a fifth threshold or higher than a sixth threshold, the feedback end of the WLAN 11ax system performs output power calibration on the WLAN 11ax system, where the initial power and the detection power are located at the same frequency, and the single frequency tone when the initial power is acquired is not transmitted in a symbol corresponding to a PE of the PPDU, and the single frequency tone when the detection power is acquired is transmitted in a symbol corresponding to the PE of the PPDU. Specifically, taking sending a single tone in a symbol corresponding to a PE as an example. As shown in fig. 6, during the initial calibration phase, a frequency f is emitted from the transmit channel 201 0 Processor 102 obtains f by analyzing the spectrum of baseband reception and processing 209a 0 The initial power at is P 0 . In the probing phase, when transmitting a packet of a PPDU with PE, a frequency f is transmitted in a symbol corresponding to PE 0 Is provided, the processor 102 obtains f by analyzing the frequency spectrum of the baseband reception and processing 209a 0 The detection power at is P1. Assuming that the fifth threshold is 0.9 and the sixth threshold is 1.1, if the ratio of P1/P0 is less than 0.9 or greater than 1.1, the deviation of the actual output power of the surface is large, which indicates that the output power calibration needs to be performed again.
Fig. 7 shows a flow chart of a method for quality condition monitoring of a transmit channel of a WLAN11ax system in accordance with an embodiment of the application. In step 701, at least one probing signal is sent in a symbol corresponding to a PE of a PPDU via a transmission channel of said WLAN11ax system based on a transmitter. In step 702, a feedback signal associated with the PPDU is acquired using a feedback channel based on a processor. In step 703, based on the data associated with the at least one probe signal in the feedback signal, the quality status of the transmitting channel is obtained, so that on the basis of adhering to the WLAN11ax protocol, multiple parameters of the transmitting radio frequency signal are monitored rapidly with a small cost, and are fed back to the feedback end rapidly, so as to remind updating the corresponding calibration.
In some embodiments, the at least one probing signal includes a single tone or a plurality of single tones of different frequencies, so as to obtain a feedback signal in the frequency spectrum, which can obviously reflect the quality condition of the transmission channel 201. Based on the data associated with the at least one detection signal in the feedback signal, acquiring the quality condition of the transmission channel, so that the feedback end of the WLAN11ax system calibrates the link of the WLAN11ax system based on the quality condition of the transmission channel specifically includes, by the processor, acquiring the quality condition of the transmission channel based on the spectrum data associated with the single frequency tone or the single frequency tones of different frequencies in the feedback signal, so that the feedback end of the WLAN11ax system calibrates the link of the WLAN11ax system based on the quality condition of the transmission channel. In this way, the accuracy in dynamically monitoring the quality condition of the transmitting channel 201 is improved, so that the feedback end of the WLAN11ax system can adjust the relevant parameters of the WLAN11ax system to realize the calibration of the link. In some embodiments, the quality condition of the transmitting channel includes IQ mismatch, and acquiring the quality condition of the transmitting channel based on spectral data associated with the one tone or multiple tones of different frequencies in the feedback signal, so that the feedback end of the WLAN11ax system calibrates the link of the WLAN11ax system based on the quality condition of the transmitting channel specifically includes, by the processor, performing IQ calibration on the WLAN11ax system if it is determined that a deviation of a signal strength at an image frequency of a first tone in the at least one probe signal with respect to a signal strength of the first tone is greater than a first threshold.
In some embodiments, the quality condition of the transmitting channel includes a DC bias, and based on spectral data associated with the single tone or multiple single tones of different frequencies in the feedback signal, obtaining the quality condition of the transmitting channel, such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmitting channel specifically includes, by the processor, when it is determined that the at least one probe signal includes one single tone, and when a deviation of a DC signal strength at a zero frequency from a signal strength of the single tone is greater than a second threshold, causing the feedback end of the WLAN 11ax system to DC calibrate the WLAN 11ax system.
In some embodiments, the quality condition of the transmitting channel includes DPD mismatch, and acquiring the quality condition of the transmitting channel based on spectrum data associated with the single tone of the plurality of different frequencies in the feedback signal, so that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmitting channel specifically includes, when the processor determines that the at least one probe signal includes at least two single tones, and the deviation of the representative value of the third-order intermodulation signal strength between the at least two single tones from the representative value of the signal strength of the at least two single tones is greater than a third threshold, causing the feedback end of the WLAN 11ax system to calibrate the DPD of the WLAN 11ax system.
In some embodiments, the quality condition of the transmitting channel includes FDIQ mismatch, and the acquiring the quality condition of the transmitting channel based on the spectral data associated with the single tone or the single tones of different frequencies in the feedback signal, so that the feedback end of the WLAN11ax system calibrates the link of the WLAN11ax system based on the quality condition of the transmitting channel specifically includes, when the processor determines that the at least one probe signal includes more than two single tones, and when a deviation of a maximum value from a minimum value in each signal intensity of each single tone in the at least one probe signal at a respective image frequency is greater than a fourth threshold, causing the feedback end of the WLAN11ax system to perform FDIQ calibration on the WLAN11ax system.
In some embodiments, the quality condition of the transmission channel includes PA output power variation, and acquiring the quality condition of the transmission channel based on the spectral data associated with the one single tone in the feedback signal, so that the calibrating, by the feedback end of the WLAN11ax system, the link of the WLAN11ax system based on the quality condition of the transmission channel specifically includes, by the processor: when judging that the at least one detection signal comprises a single frequency tone, acquiring initial power of the single frequency tone in an initial calibration stage and detection power in a detection stage, and under the condition that the deviation between the detection power and the initial power is smaller than a fifth threshold value or higher than a sixth threshold value, enabling a feedback end of the WLAN11ax system to calibrate output power of the WLAN11ax system; the initial power and the detection power are located at the same frequency, the single-frequency tone when the initial power is acquired is not transmitted in a symbol corresponding to the PE of the PPDU, and the single-frequency tone when the detection power is acquired is transmitted in the symbol corresponding to the PE of the PPDU.
The present application describes various operations or functions that may be implemented or defined as software code or instructions. Such content may be source code or differential code ("delta" or "patch" code) ("object" or "executable" form) that may be executed directly. The software code or instructions may be stored in a computer readable storage medium and, when executed, may cause a machine to perform the functions or operations described and include any mechanism that stores information in a form accessible by a machine (e.g., computing device, electronic system, etc.), such as recordable or non-recordable media (e.g., read Only Memory (ROM), random Access Memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, etc.).
The exemplary methods described herein may be implemented, at least in part, by a machine or computer. In some embodiments, a computer readable storage medium has stored thereon computer program instructions which, when executed by a processor, cause the processor to perform a method for WLAN 11ax system transmit channel quality condition monitoring according to various embodiments of the application. Implementations of such methods may include software code, such as microcode, assembly language code, higher-level language code, or the like. Various software programming techniques may be used to create various programs or program modules. For example, program portions or program modules may be designed in or with the aid of Java, python, C, C ++, assembly language, or any known programming language. One or more of such software portions or modules may be integrated into a computer system and/or computer readable medium. Such software code may include computer readable instructions for performing various methods. The software code may form part of a computer program product or a computer program module. Furthermore, in examples, the software code may be tangibly stored on one or more volatile, non-transitory, or non-volatile tangible computer-readable media, such as during execution or at other times. Examples of such tangible computer-readable media may include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., optical disks and digital video disks), magnetic cassettes, memory cards or sticks, random Access Memories (RAMs), read Only Memories (ROMs), and the like.
The method and the device of the application are subjected to various modifications and changes. Other embodiments may be derived by those skilled in the art from the description and practice of the disclosed system and related methods. The various claims of the application are to be understood as separate embodiments and any combination thereof is also to be regarded as embodiments of the application and all such embodiments are to be considered as included in the application.
The examples are to be considered as illustrative only, with a true scope being indicated by the following claims and their equivalents.
Claims (12)
1. A system for monitoring the quality condition of a transmission channel of a WLAN 11ax system, the system comprising:
a transmitter configured to transmit at least one sounding signal within a symbol corresponding to a PE of a PPDU via a transmission channel of the WLAN 11ax system, the at least one sounding signal comprising one tone or a plurality of tones of different frequencies; and
a processor configured to collect a feedback signal associated with the PPDU using a feedback channel; and acquiring a quality condition of the transmitting channel based on spectrum data associated with the single tone or the plurality of single tones with different frequencies in the feedback signal, wherein when the quality condition comprises IQ mismatch, the feedback end of the WLAN 11ax system performs IQ calibration on the WLAN 11ax system when the deviation of the signal intensity at the mirror frequency of the first single tone in the at least one detection signal relative to the signal intensity of the first single tone is judged to be greater than a first threshold.
2. The system of claim 1, wherein the quality condition of the transmit channel comprises a DC bias, wherein the acquiring the quality condition of the transmit channel based on spectral data associated with the one tone or the plurality of different tones in the feedback signal such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises, in particular, by the processor:
and under the condition that the at least one detection signal comprises a single frequency tone and the deviation of the DC signal intensity at the zero frequency relative to the signal intensity of the single frequency tone is larger than a second threshold value, enabling a feedback end of the WLAN 11ax system to conduct DC calibration on the WLAN 11ax system.
3. The system of claim 1, wherein the quality condition of the transmit channel comprises a DPD mismatch, wherein the obtaining the quality condition of the transmit channel based on spectral data associated with the plurality of different frequency tones in the feedback signal, such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises:
And under the condition that the at least one detection signal comprises at least two single-frequency tones and the deviation of the representative value of the third-order intermodulation signal intensity between the at least two single-frequency tones relative to the representative value of the signal intensity of the at least two single-frequency tones is larger than a third threshold value, enabling a feedback end of the WLAN 11ax system to carry out DPD calibration on the WLAN 11ax system.
4. The system of claim 1, wherein when the quality condition of the transmit channel comprises an FDIQ mismatch, obtaining the quality condition of the transmit channel based on spectral data associated with the one tone or the plurality of different tones in the feedback signal such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises, in particular, by the processor:
and under the condition that the at least one detection signal comprises more than two single frequency tone and the deviation of the maximum value relative to the minimum value in the signal intensity of each single frequency tone at the respective image frequency in the at least one detection signal is larger than a fourth threshold value, the feedback end of the WLAN 11ax system performs FDIQ calibration on the WLAN 11ax system.
5. The system of claim 1, wherein when the quality condition of the transmit channel includes PA output power variation, obtaining the quality condition of the transmit channel based on spectral data associated with the one single tone in the feedback signal, such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises, in particular, by the processor:
when judging that the at least one detection signal comprises a single frequency tone, acquiring initial power of the single frequency tone in an initial calibration stage and detection power in a detection stage, and under the condition that the deviation between the detection power and the initial power is smaller than a fifth threshold value or higher than a sixth threshold value, enabling a feedback end of the WLAN 11ax system to calibrate output power of the WLAN 11ax system; the initial power and the detection power are located at the same frequency, the single-frequency tone when the initial power is acquired is not transmitted in a symbol corresponding to the PE of the PPDU, and the single-frequency tone when the detection power is acquired is transmitted in the symbol corresponding to the PE of the PPDU.
6. The system of any of claims 1-5, wherein the deviation comprises a ratio.
7. A method for monitoring a transmit channel quality condition of a WLAN 11ax system, comprising:
based on a transmitter, transmitting at least one detection signal in a symbol corresponding to PE of a PPDU through a transmission channel of the WLAN 11ax system, wherein the at least one detection signal comprises one single-frequency tone or a plurality of single-frequency tones with different frequencies; and
based on a processor, collecting a feedback signal associated with the PPDU using a feedback channel; and is also provided with
And acquiring the quality condition of the transmitting channel based on spectrum data associated with the single tone or the single tones with different frequencies in the feedback signal, and under the condition that the quality condition comprises IQ mismatch, under the condition that the deviation of the signal intensity at the mirror frequency of the first single tone in the at least one detection signal relative to the signal intensity of the first single tone is larger than a first threshold value, enabling a feedback end of the WLAN 11ax system to perform IQ calibration on the WLAN 11ax system.
8. The method of claim 7, wherein the quality condition of the transmit channel comprises a DC bias, wherein obtaining the quality condition of the transmit channel based on spectral data associated with the one tone or a plurality of different tones in the feedback signal such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises, in particular, by the processor:
And under the condition that the at least one detection signal comprises a single frequency tone and the deviation of the DC signal intensity at the zero frequency relative to the signal intensity of the single frequency tone is larger than a second threshold value, enabling a feedback end of the WLAN 11ax system to conduct DC calibration on the WLAN 11ax system.
9. The method of claim 7, wherein the quality condition of the transmit channel comprises a DPD mismatch, wherein obtaining the quality condition of the transmit channel based on spectral data associated with a plurality of different frequency tones in the feedback signal such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises:
and under the condition that the at least one detection signal comprises at least two single-frequency tones and the deviation of the representative value of the third-order intermodulation signal intensity between the at least two single-frequency tones relative to the representative value of the signal intensity of the at least two single-frequency tones is larger than a third threshold value, enabling a feedback end of the WLAN 11ax system to carry out DPD calibration on the WLAN 11ax system.
10. The method of claim 7, wherein when the quality condition of the transmit channel comprises an FDIQ mismatch, obtaining the quality condition of the transmit channel based on spectral data associated with the one tone or the plurality of different tones in the feedback signal such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel, specifically comprises, by the processor:
And under the condition that the at least one detection signal comprises more than two single frequency tone and the deviation of the maximum value relative to the minimum value in the signal intensity of each single frequency tone at the respective image frequency in the at least one detection signal is larger than a fourth threshold value, the feedback end of the WLAN 11ax system performs FDIQ calibration on the WLAN 11ax system.
11. The method of claim 7, wherein when the quality condition of the transmit channel includes PA output power variation, obtaining the quality condition of the transmit channel based on spectral data associated with the one single tone in the feedback signal, such that the feedback end of the WLAN 11ax system calibrates the link of the WLAN 11ax system based on the quality condition of the transmit channel comprises, in particular, by the processor:
when judging that the at least one detection signal comprises a single frequency tone, acquiring initial power of the single frequency tone in an initial calibration stage and detection power in a detection stage, and under the condition that the deviation between the detection power and the initial power is smaller than a fifth threshold value or higher than a sixth threshold value, enabling a feedback end of the WLAN 11ax system to calibrate output power of the WLAN 11ax system; the initial power and the detection power are located at the same frequency, the single-frequency tone when the initial power is acquired is not transmitted in a symbol corresponding to the PE of the PPDU, and the single-frequency tone when the detection power is acquired is transmitted in the symbol corresponding to the PE of the PPDU.
12. A computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, cause the processor to perform the method for WLAN 11ax system transmit channel quality condition monitoring of any of claims 7-11.
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| CN110199549A (en) * | 2017-01-19 | 2019-09-03 | 高通股份有限公司 | Packet-based link aggregation framework |
| CN114556797A (en) * | 2019-10-31 | 2022-05-27 | 松下电器（美国）知识产权公司 | Communication apparatus and communication method for channel estimation |
| CN113765831A (en) * | 2020-06-05 | 2021-12-07 | 华为技术有限公司 | PPDU transmission method and related device |
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