CN112514465A

CN112514465A - Network control

Info

Publication number: CN112514465A
Application number: CN201980017910.1A
Authority: CN
Inventors: ***·阿萨德; 李维杰
Original assignee: Central Polytechnic Higher Institute Of Electric Power Paris; Jiekai Communications Shenzhen Co Ltd
Current assignee: Central Polytechnic Higher Institute Of Electric Power Paris; JRD Communication Shenzhen Ltd; Jiekai Communications Shenzhen Co Ltd; CentraleSupelec
Priority date: 2018-03-08
Filing date: 2019-03-08
Publication date: 2021-03-16
Also published as: GB2571769A; GB2571769B; GB201803740D0; WO2019170138A1

Abstract

A network control system, wherein a sending end receives a service quality indication from a receiving end and configures transmission resources according to the received service quality indication. The sender may receive quality of service indications from a receiver connected to different senders for resource configuration.

Description

Network control

Technical Field

The present application relates to control of cellular networks and in particular to control of base station transmission characteristics.

Background

Wireless communication systems, such as third generation (3G) mobile telephone standards and techniques are well known. The 3G standards and technologies were developed by the Third Generation Partnership Project (3 GPP). Third generation wireless communications were developed to support macro cellular mobile telephone communications. Communication systems and networks are evolving towards broadband mobile systems.

In a cellular Radio communication system, a User Equipment (UE) is connected to a Radio Access Network (RAN) via a Radio link. The RAN includes: a set of base stations providing radio links to UEs located in cells covered by the set of base stations; and an interface to a Core Network (CN) that provides over Network control. It should be noted that the RAN and the CN perform their respective functions in the entire network. For convenience, the term "cellular network" refers to the combined RAN and CN, and as will be appreciated, is used to refer to the various systems that perform the disclosed functions.

The third generation partnership project has developed a so-called Long Term Evolution (LTE) System, i.e., an Evolved Universal terrestrial Radio Access Network (E-UTRAN), in which one or more macrocells are supported by a base station eNodeB or eNB (Evolved NodeB). Recently, LTE has further evolved towards so-called 5G or NR (New Radio) systems, where one or more macrocells are supported by a base station gN. NR proposes the use of an Orthogonal Frequency Division Multiplexing (OFDM) physical transmission format.

In a cellular wireless communication network, a physical space and a set of transmission resources are shared between a plurality of UEs connected to a base station of the cellular network. Interference may occur between each UE and the signal between the base station, and may also occur between other base stations and the UE. To ensure efficient use of the available resources while ensuring optimal (or acceptable) performance for each link, the resources and parameters used by each base station-UE link must be configured correctly. For example, the optimal power transmitted to a UE farther from the base station may be higher than the optimal power transmitted to a UE closer to the base station.

Existing methods of optimizing network resource allocation rely on a complete knowledge of the channel state (or quality) information (CSI/CQI) of all interfering links. However, usually only incomplete CSI/CQI information is available, resulting in an undesirable resource configuration.

The present application therefore seeks to address at least some of the salient problems of this field.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

The present application provides a method of configuring radio link resources in a cellular communication network comprising a plurality of base stations, each base station being wirelessly connected to at least one mobile device, the method being performed by one of the base stations, the method comprising: transmitting signals from the base station to at least one mobile device connected to the base station, the signals employing transmission resources

To transmit; receiving, at the base station, a quality of service indication, the quality of service indication being received by a mobile device transmitted by the signal and/or the quality of service indication being received by at least one other mobile device connected to the cellular communication network; obtaining a transmission resource value for further transmission from the base station to the mobile device

The value is

Based on

And the received quality of service indication; and, using the transmission resource

Another signal is transmitted from the base station to the mobile device.

The transmission resource may be a transmission power.

In one particular method:

μ_kin order to have the sequence disappear,

k is the number of iterations,

i is the index of the sending end,

δ_i，ke { -1, 1}, wherein

And is

λ_kIn order to have the sequence disappear,

if it is

Is not empty; if not, then,

vanishing step length lambda_kAnd mu_kCan satisfy

And is

The quality of service indication may be:

the method may further comprise the step of transmitting the quality of service indication received by the first eNb to the second eNb.

The present application also provides an eNb configured to perform the above method.

The present application also provides a non-transitory computer-readable storage medium, which may include at least one of a hard disk, a Compact Disc Read Only Memory (CD-ROM), an optical Memory, a magnetic Memory, a Read Only Memory (ROM), a Programmable Read Only Memory (PROM), an Erasable Programmable Read Only Memory (EPROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), and a Flash Memory.

Drawings

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Elements in the figures have been simplified and are not necessarily drawn to scale. For ease of understanding, reference numerals have been included in the various figures.

Fig. 1 is a schematic diagram of a transmitting end and a receiving end;

FIG. 2 is a flow diagram of resource configuration;

FIG. 3 is a schematic diagram of a cellular network;

fig. 4 to 9 are schematic diagrams of simulation results.

Detailed Description

The embodiments described herein are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

An iterative configuration process (process) is described to find the best configuration of resources in a cellular wireless network. In particular, the process addresses (addresses) resource configurations of base stations that are used to transmit signals to UEs connected to the base stations. The process aims to manage the amount of data transfer for performing the process, thereby controlling the network overhead (overhead).

In existing resource allocation schemes, all UEs use the same feedback parameter, typically CSI or CQI, to inform the base station of the channel quality. However, in the process discussed below, each UE provides feedback on its service using a utility function (utility function) related to the currently provided service. The particular utility function of the service being used may provide more relevant feedback for the quality of service received by the UE. The CSI or CQI does not necessarily reflect the quality of service for a certain service, so the use of a utility function may improve the quality of the feedback.

Fig. 1 shows a set of signal paths involved in communication between N transmitters and N receivers. Each transmitting end and each receiving end form a pair. In a specific example, the transmitting end is a base station, and the receiving end is a mobile device or a UE. Each transmitter may be a discrete base station or may be provided by other transmitters that are the same as the base station. As shown in fig. 1a, the signal is in power

From the transmitting end to the receiving end, where k is the number of iterations. As shown in FIG. 1b, each receiver transmits its local utility of the quantized estimate

It depends on the power set (power set) of all transmitters and on the random channelStatus (stored channel state). All transmitters may receive and decode the local utility and each transmitter may use the local utility values from multiple UEs when performing the resource allocation procedure.

The resource allocation procedure is run by updating the actual transmission power of each transmitting end,

based on defined algorithms and feedback. For some of the systems that are used,

other factors may be indicated instead of or in addition to the transmission power. For example, the beam direction or width may be indicated, since these parameters also define the effective power reaching the UE.

The following parameters were used in the process:

μ_kis a predefined sequence of vanishing sequences (common) for each sender, e.g., mu_k＝k^-0.3。

δ_i，kE { -1, 1} is an independent pseudo random scalar (pseudo random scale). Sequence delta_i，0，K，δ_l， _kK may be any known sequence, for example, Gold sequence (Gold sequence) or M sequence (M-sequence). In general, the pseudorandom sequence satisfies the following properties:

and is

p_i，kIs used for calculating

May be set arbitrarily at the start of the process.

For a given iteration of the process, the process may,

these variables are used.

Fig. 2 shows a flow chart of a resource allocation method. In step 20, each transmitting end sets its transmission power to

And transmits the message to the used power in step 21

The correlation receiver of (1). At step 22, each receiver receives the message and estimates its actual local utility y_i，kThe actual local utility is used to give a quantized local utility

The local utility is defined based on the service currently used on the transmit/receive link. For example, the local utility may be related to the bit rate, throughput rate, error rate, or energy efficiency of the link. The selected local utility may depend on the particular service and parameters important to the quality of the service or parameters indicative of the quality of the service. For example, for some services, bit rate may be more important than error rate. The local utility may be different for each receiver.

In step 23, the UE transmits its quantized local utility, which may be received by one or more transmitting ends. For example, a broadcast transmission may be used that can be received and decoded by all transmitters within range of the associated receiver.

If R is used to represent

Then the amount of signal transmitted by each receiver in each iteration of the process is R bits. The exact value of R (exact value) may be selected based on the utility function and the particular application. If the quantity term (quantifier) is unbiased (non-biased), then the value of R has no critical effect on the convergence of the solution process (convergence).

At step 24, the sender receives the quantized local utility transmitted by all senders within range. This may be all or a subset of the receiving ends that have links that may interfere with a particular transmitting end. As described below, the local utility value is used to calculate a global utility (global utility) of the network. As the number of received local utility values increases, the accuracy of the global utility value also increases. However, the process does not rely on knowing all local utility values, so receiving only a subset does not prevent operation.

If it is assumed that the transmitting end only acquires the subset of the receiving end

Then for the transmission of iteration k, the global utility can be estimated as:

if it is

If it is not empty, then

If not, then,

from the utility value received from iteration k, the sender moves to iteration k +1 to compute a new resource allocation.

In step 25, each sender updates its p according to the following rules_i，k+1The value:

wherein λ is_kIs a predefined disappearance sequence (with μ) common to all senders_kSimilarly). It should be noted that the receiving end does not require knowledge of λ_kOr mu_k。

Further, at step 26, each sender may calculate its new transmission power:

it should be noted that the projection (projection) of the above formula ensures

Satisfying power constraints

Steps 21 to 26 may be repeated if the step size (disappearing step-sizes) lambda is disappeared_kAnd mu_kThe following properties are satisfied:

and is

Then for any receiver i, p_i，kAnd

should converge to an optimum value after sufficient iterations

It is noted that the step size can be freely chosen, e.g. λ_k＝λ₀k^-a，μ_k＝μ₀k^-b，a∈(0.5，1)，b∈(0，1-a).

Thus, a procedure is provided for optimizing resource allocation, in particular transmission power, by a plurality of transmitting terminals. Feedback indicating the quality of service is provided from the receiving end to the transmitting end in the form of a utility function.

Fig. 3 shows an example of a cellular network in which the process of fig. 2 may be implemented. eNb (eNb1, eNb2, eNb3) represents the transmitting end, and UE (UE1, UE2, UE3, UE4) represents the receiving end. This procedure is used to optimize the transmission resources from the eNb to the UE.

Fig. 3a shows downlink transmissions from each eNB to its associated UE, and messages transmitted at iteration k with transmission power. Fig. 3b shows uplink transmissions (solid arrows) from each UE to its associated base station, including estimated and quantized local utility as feedback. All enbs listen to such feedback and receive and decode all interpretable (interpreted) information. Fig. 3b also shows a solid line representing the X2 interface between the eNb, the X2 interface being available for exchanging information. The X2 interface can be used to exchange feedback information between the eNb and thus not rely on successful reception directly from the UE. For example, each UE may send its feedback message to the eNb to which it is connected, and each eNb may then send the feedback information to the other enbs via the X2 interface (or another suitable communication path).

If it is not

Denotes a set of UEs associated with eNB j, of size N_jThe total amount of signaling information appearing at eNb j is RN_jAnd a bit. However, for each eNb j, the RN is sent to all other eNBs_jSignaling information of a single bit is not necessary. Conversely, eNb j may only send signaling information to one or a few eNb (e.g., the eNb may send the signaling information to a subset of eNb's that are selected using a random, round robin, or any other algorithm). In this case, the eNb does not have the same information about the utility functions of the different users in the network. Also, eNb may delay the utility information for certain users. However, although the information is incomplete, it can be proved that the process converges on the optimal solution, but the convergence speed may be reduced. Therefore, a trade-off is required between signaling overhead and convergence speed.

It can thus be seen that the procedure as shown in fig. 2 can be implemented in a cellular network to optimize the resource allocation of the downlink between the eNb and the UE.

By way of specific example (but not limited to this example), with N-4 transmit-receive pairs in a wireless network, the power control problem is set forth below. g_ij，kDenotes the sender (or base station) i and receiver at iteration kThe channel gain between (or users) j. A simple (type Proportional fair) local utility function is used:

a global utility function of

The optimal solution is to find the global function

Solution at maximum. This optimal solution can be achieved by using a gradient-based descent method, which requires each sender i to calculate:

wherein the content of the first and second substances,

the calculation of the exact derivative requires additional information: SINR is also required, and the transmitting end i also needs to know all the transmitting ends

And the channel gain g between the receiving end i_ni，kAnd optionally

Is/are as follows

Values, e.g., actions performed by sender n in a previous iteration. This indicates that by feeding back the SINR (or quantized SINR version, e.g. CQI), the optimal solution cannot be achieved using existing resource allocation schemes, because of the g of other links_ni，kAnd

the necessary information of is lost. However, the present disclosure is based on using a quantized utility function as feedback in conjunction with a new resource allocation strategy. The following shows that this scheme allows convergence to an optimal solution. Simulations were performed for different numbers of users.

In the following simulation, a time varying channel h between a sender i and a receiver j_ij，kGenerated using a Gaussian distribution (Gaussian distribution) with variance of, for any i ≠ j

Channel gain of g_ij，k＝|h_ij，k|²，σ²＝0.2，η₁20, and η ₂1. In this algorithm, λ_k＝1.5k^-0.68，μ_k＝10k^-0.26Generating p collectively in the interval (0, 20)_i，0Is started. Consider the case where each sender has incomplete information of local utility. For q ∈ {1,0.5,0.25,0.1}, and q is the probability of receiving any receiver-side feedback, 100 independent simulations were performed.

Fig. 4 shows the global utility function as a function of the number of iterations. Fig. 5 shows the evolution of the power set for any transmit end (note that the curves for different transmit ends have similar shapes). To show the efficiency of the algorithm, a line representing the average utility function and the optimum value of power is plotted in fig. 4 and 5, respectively. It can be seen that the convergence rate decreases as the q value decreases. Even if q is 0.5, the effect is not significant, i.e. the transmitting end has 50% chance to know the local utility of the receiving end.

Fig. 6 and 7 show graphs similar to fig. 4 and 5, but with the following parameters:

N＝10

for any i ≠ j,

λ_k＝2k^-0.7，μ_k＝12k^-0.25。

fig. 8 and 9 show another result with the following parameters:

N＝15；

for any i ≠ j,

λ_k＝2k^-0.7，μ_k＝12k^-0.25。

thus, the described process converges to an optimal solution even if the feedback from the UE to the base station is incomplete.

Although it is not described in detail that any device or apparatus forming part of a network may include at least one processor, memory unit, and communication interface, the processor, memory unit, and communication interface are configured to perform the methods of any aspect of the present application. Further options and choices are described below.

The signal processing functions in the embodiments of the present application, particularly the signal processing capabilities of the gNB and the UE, may be implemented by computing systems or architectures that are well known to those skilled in the art. The computing system may be a desktop, laptop or notebook computer, hand-held computing device (PDA, cell phone, palmtop, etc.), mainframe, server, client, or any other type of special or general purpose computing device as may be satisfactory or applicable to a given application or environment. The computing system may include one or more processors that may execute a general or special purpose processing engine such as, for example, a microprocessor, microcontroller or other control module.

The computing system may also include a main Memory, such as Random Access Memory (RAM) or other dynamic Memory, for storing information and instructions to be executed by the processor. The main memory may also be used for storing temporary variables or other intermediate information during execution of instructions by the processor. The computing system may also include a Read Only Memory (ROM) or other static storage device for storing static information and instructions for execution by the processor.

The computing system may also include an information storage system including, for example, a media drive and a removable storage interface. The media drive may include a drive or other mechanism to support fixed or removable storage media, such as a hard disk drive, a floppy disk drive, a magnetic tape drive, an optical disk drive, a compact disk drive (CD) or Digital Video Drive (DVD) read-write drive (R or RW), or other fixed or removable media drive. The storage medium may include, for example, a hard disk, floppy disk, magnetic tape, optical disk, CD, DVD, or other fixed or removable medium that is read by and written to by a media drive. The storage media may include a computer-readable storage medium having stored thereon particular computer software or data.

In alternative embodiments, the information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. These components may include, for example, a removable storage unit and interface, such as a program cartridge and cartridge interface, a removable memory (e.g., a flash memory or other removable memory module) and memory slot, and other removable storage units and interfaces that allow software and data to be transferred from the removable storage unit to the computing system.

The computing system may also include a communication interface. The communication interface may be used to allow software and data to be transferred between the computing system and external devices. For example, the communication interfaces can include a modem, a network interface (such as an Ethernet or other network card), a communication port (such as a Universal Serial Bus (USB) port), a PCMCIA slot and card, and the like. Software and data transferred via the communications interface are in the form of signals which may be electronic, electromagnetic, optical or other signals capable of being received by the communications interface medium.

In this application, the terms "computer program product," "computer-readable medium," and the like are used generally to refer to tangible media, such as memory, storage devices, or storage units. These and other forms of computer-readable media may store one or more instructions for use by a processor, including a computer system, to cause the processor to perform specified operations. These instructions, which are generally referred to as "computer program code" (which may be grouped in the form of computer programs or other groupings), when executed, enable the computer system to perform functions of embodiments of the present application. It is noted that the code may directly cause the processor to perform specified operations, may be compiled to do so, and/or may be combined with other software, hardware, and/or firmware elements (e.g., libraries for performing standard functions) to do so.

The non-computer readable medium may comprise at least one from the group of: hard disks, Compact disk Read Only memories (CD-ROMs), optical storage devices, magnetic storage devices, Read Only Memories (ROMs), Programmable Read Only Memories (PROMs), Erasable Programmable Read Only Memories (EPROMs), Electrically Erasable Programmable Read Only Memories (EEPROMs), and Flash memories (Flash memories).

In embodiments implemented by software, the software may be stored in a computer-readable medium and loaded into the computing system using, for example, a removable storage drive. A control module (e.g., software instructions or executable computer program code) executed by a processor in a computer system causes the processor to perform functions as described herein.

Further, the present application may be applied in any circuit for performing signal processing functions in a network element. For example, it is further contemplated that a semiconductor manufacturer may employ the innovative concepts in the design of a stand-alone device, which may be a microcontroller (DSP) of a digital signal processor, an Application Specific Integrated Circuit (ASIC), and/or any other subsystem element.

For clarity of description, the foregoing description has described embodiments of the present application with reference to a single processing logic. However, the present application may equally well implement signal processing functions by means of a plurality of different functional units and processors. Thus, references to specific functional units are only to be seen as references to suitable means for providing the described functionality rather than indicative of a strict logical, physical structure or organization.

Aspects of the present application may be implemented in any suitable form including hardware, software, firmware or any combination of these. The present application may optionally be implemented, at least partly, as computer software, a computer software component, such as an FPGA device, running on one or more data processors and/or digital signal processors or configurable modules. Thus, the elements and components of an embodiment of the application may be physically, functionally and logically implemented in any suitable way. Indeed the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units.

Although the present application has been described with reference to the preferred embodiments, the above-described preferred embodiments are not intended to limit the present application, and the scope of the present application is defined by the following claims. Furthermore, while descriptions of features related to particular embodiments may appear, one skilled in the art may, in light of the present disclosure, appreciate various features of such embodiments. In the claims, the term "comprising" does not exclude the presence of other elements or steps.

Further, although individually listed, a plurality of means, elements or method steps may be implemented by e.g. a single unit or processor. Furthermore, although different features may comprise different claims, these may possibly advantageously be combined, and the inclusion in different claims does not imply that a combination of features is not feasible and/or advantageous. Likewise, the inclusion of a feature in one set of claims does not imply a limitation to this set of claims, but rather indicates that the feature is equally applicable to other claim categories, as appropriate.

Further, the ordering of features in the claims does not imply that the features must be performed in a particular order, and in particular the order of individual steps in a method claim does not imply that the steps must be performed in this order. Rather, the steps may be performed in any suitable order. Furthermore, singular references do not exclude a plurality. Thus, the singular forms "a", "an", "first", "second", etc. do not exclude the plural forms.

Although the present application has been described with reference to the preferred embodiments, the above-described preferred embodiments are not intended to limit the present application, and the scope of the present application is defined by the following claims. Furthermore, while descriptions of features related to particular embodiments may appear, one skilled in the art may, in light of the present disclosure, appreciate various features of such embodiments. In the claims, the term "comprising" or "including" does not exclude the presence of other elements.

Claims

1. A method of configuring radio link resources in a cellular communication network, the cellular communication network comprising a plurality of base stations, each base station being wirelessly connected to at least one mobile device, the method being performed by one of the base stations, the method comprising:

transmitting signals from the base station to at least one mobile device connected to the base station, the signals employing transmission resources

To transmit;

receiving, at the base station, a quality of service indication, the quality of service indication being received by a mobile device transmitted by the signal and/or the quality of service indication being received by at least one other mobile device connected to the cellular communication network;

obtaining a transmission resource value for further transmission from the base station to the mobile device

The value is

Based on

And the received clothesA quality of service indication; and the number of the first and second groups,

using transmission resources

Another signal is transmitted from the base station to the mobile device.

2. The method of claim 1, wherein the transmission resource is transmission power.

3. The method according to claim 1 or 2,

μ_kin order to have the sequence disappear,

k is the number of iterations,

i is the index of the sending end,

δ_i，ke { -1, 1}, wherein

And is

λ_kIn order to have the sequence disappear,

if it is

Is not empty; if not, then,

4. method according to claim 3, characterized in that the disappearance step λ_kAnd mu_kSatisfy the requirement of

And is

5. The method according to any of claims 1 to 4, wherein the quality of service indication is

6. The method of any of claims 1 to 5, further comprising the step of transmitting the quality of service indication received by the first eNb to the second eNb.

7. An eNb configured to perform the method of any of claims 1 to 6.