CN106465422A

CN106465422A - Communication method, base station, and terminal device

Info

Publication number: CN106465422A
Application number: CN201480079691.7A
Authority: CN
Inventors: 张朝阳; 王献斌; 张昱; 张亮; 张舜卿; 陈雁
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-11-04
Filing date: 2014-11-04
Publication date: 2017-02-22
Anticipated expiration: 2034-11-04
Also published as: CN106465422B; WO2016070325A1

Abstract

Disclosed are a communication method, a base station, and a terminal device. The method comprises: determining, according to system state information, access degree probability distribution information used when a terminal device conducts communication, the system state information comprising the total number of users, or comprising at least one of an amount of data to be transmitted, a signal-to-noise ratio (SNR) and quality of service (QoS) as well as the total number of users; sending the access degree probability distribution information to the terminal device, the access degree probability distribution information being used for indicating a corresponding probability or probabilities when the terminal device separately sends data by using one or more specific access degrees; and receiving data sent by the terminal device according to the access degree probability distribution information. Embodiments of the present invention can reduce signaling overheads of a system.

Description

Communication method, base station and terminal equipment

Technical Field

The present invention relates to the field of communications, and in particular, to a communication method, a base station, and a terminal device.

Background

With the development of technologies such as internet of things, internet of vehicles, ad hoc networks and the like, cell densification is a trend of future networks. Massive Access (english) is one of the typical scenarios of future networks. The large-scale access scene has the following characteristics: firstly, the number of potential access users is large and dynamic; secondly, the access network structure is complex, the topology is changeable, and the channel characteristics are dynamically changed; thirdly, the service types are complex, and the access data volume and the time delay requirements of different users are obviously different.

In a large-scale access scenario, if a base station determines and allocates communication resources (e.g., time, frequency, code, and other resources) used by each terminal device for communication in advance, a large amount of signaling overhead is required. In such a scenario, the system needs a communication method based on a new access mechanism to reduce the signaling overhead of the system.

Disclosure of Invention

The embodiment of the invention provides a communication method, a base station and terminal equipment, which can reduce the signaling overhead of a system.

In a first aspect, an embodiment of the present invention provides a communication method, including:

determining access degree probability distribution information used during communication of the terminal equipment according to system state information, wherein the system state information comprises the total number of users, or at least one of data volume to be transmitted, signal-to-noise ratio (SNR) and quality of service (QoS), and the total number of users;

sending access degree probability distribution information to the terminal equipment, wherein the access degree probability distribution information is used for indicating the corresponding probability when the terminal equipment sends data respectively with one or more specific access degrees;

and receiving data sent by the terminal equipment according to the access degree probability distribution information.

With reference to the first aspect, in a first implementation manner of the first aspect, determining, according to the system state information, access degree probability distribution information used when the terminal device performs communication includes:

determining the target average access degree of the terminal equipment according to the system state information;

and determining the access degree probability distribution information used by the terminal equipment during communication according to the target average access degree.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a second implementation manner of the first aspect, the method further includes:

determining the coding rate of the terminal equipment according to the system throughput rate requirement; and sending the coding rate to the terminal equipment, wherein the coding rate is used for indicating the coding rate used when the terminal equipment carries out coding.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a third implementation manner of the first aspect, after receiving data sent by a terminal device according to access degree probability distribution information, the method further includes:

and when the data sent by the terminal equipment is decoded successfully, sending feedback information to the terminal equipment.

With reference to the first aspect and the foregoing implementation manner of the first aspect, in a fourth implementation manner of the first aspect, the sending access degree probability distribution information to a terminal device includes:

and sending the access degree probability distribution information to the terminal equipment in a broadcasting mode.

In a second aspect, an embodiment of the present invention provides a communication method, including: receiving access degree probability distribution information used when the terminal equipment communicates from a base station, wherein the access degree probability distribution information is used for indicating the corresponding probability when the terminal equipment respectively sends data with one or more specific access degrees;

and respectively sending the data to be sent to the base station according to the access degree probability distribution information and the specific access degree or degrees and the corresponding probability.

With reference to the second aspect, in a first implementation manner of the second aspect, before sending data to be sent to a base station with a specific one or more access degrees and corresponding probabilities according to the access degree probability distribution information, the method further includes:

receiving a coding rate from a base station, wherein the coding rate is determined by the base station according to the system throughput rate requirement;

coding data to be transmitted by using the coding rate as a fixed rate to obtain coding bits;

and modulating the coded bits to obtain a modulation symbol sequence.

With reference to the second aspect and the foregoing implementation manner of the second aspect, in a second implementation manner of the second aspect, respectively sending data to be sent to a base station with a specific one or more access degrees and corresponding probabilities according to access degree probability distribution information, includes:

determining the access degree d when the data is sent according to the access degree probability distribution information, wherein the d is a non-negative integer;

d symbols are selected from the modulation symbol sequence to be linearly added, and the result of the linear addition is sent to the base station.

With reference to the second aspect and the foregoing implementation manner, in a third implementation manner of the second aspect, after respectively sending data to be sent to a base station with a specific one or more access degrees and corresponding probabilities according to access degree probability distribution information, the method further includes:

and when the feedback information is received from the base station, stopping sending the data to be sent to the base station.

In a third aspect, an embodiment of the present invention provides a base station, including:

a determining unit, configured to determine, according to system state information, access degree probability distribution information used during communication of a terminal device, where the system state information includes a total number of users, or at least one of a data amount to be transmitted, a signal-to-noise ratio (SNR), and a quality of service (QoS), and the total number of users;

a sending unit, configured to send access degree probability distribution information to a terminal device, where the access degree probability distribution information is used to indicate corresponding probabilities when the terminal device sends data with a specific one or multiple access degrees respectively;

and the receiving unit is used for receiving the data sent by the terminal equipment according to the access degree probability distribution information.

With reference to the third aspect, in a first implementation manner of the third aspect, the determining unit is specifically configured to,

With reference to the third aspect and the foregoing implementation manner, in a second implementation manner of the third aspect, the determining unit is further configured to determine an encoding rate of the terminal device according to a requirement of a system throughput;

and the sending unit is further configured to send a coding rate to the terminal device, where the coding rate is used to indicate a coding rate used when the terminal device performs coding.

With reference to the third aspect and the foregoing implementation manner of the third aspect, in a third implementation manner of the third aspect, the sending unit is further configured to send feedback information to the terminal device when the data sent by the terminal device is successfully decoded.

With reference to the third aspect and the foregoing implementation manner of the third aspect, in a fourth implementation manner of the third aspect, the sending unit is specifically configured to send the access degree probability distribution information to the terminal device in a broadcast manner.

In a fourth aspect, an embodiment of the present invention provides a terminal device, including:

a receiving unit, configured to receive, from a base station, access degree probability distribution information used when a terminal device communicates, where the access degree probability distribution information is used to indicate probabilities corresponding to when the terminal device transmits data with a specific one or multiple access degrees, respectively;

and the sending unit is used for sending the data to be sent to the base station according to the access degree probability distribution information and the specific access degree or the specific access degrees and the corresponding probabilities.

With reference to the fourth aspect, in a first implementation manner of the fourth aspect, the terminal device further includes a coding unit and a modulation unit,

the receiving unit is also used for receiving the coding rate from the base station, and the coding rate is determined by the base station according to the system throughput rate requirement;

the encoding unit is used for encoding data to be transmitted by taking the encoding code rate as a fixed code rate to obtain encoding bits;

and the modulation unit is used for modulating the coded bits to obtain a modulation symbol sequence.

With reference to the fourth aspect and the foregoing implementation manner of the fourth aspect, in a second implementation manner of the fourth aspect, the sending unit is specifically configured to,

d symbols are selected from data to be transmitted for linear addition, and the result after the linear addition is transmitted to a base station.

With reference to the fourth aspect and the foregoing implementation manner of the fourth aspect, in a third implementation manner of the fourth aspect, the sending unit is further configured to stop sending the data to be sent to the base station when the terminal device receives the feedback information from the base station.

Based on the above technical solution, in the embodiment of the present invention, the terminal device receives the access degree probability distribution information from the base station. Then, according to the access degree probability distribution information, the corresponding time frequency resource is occupied to transmit data, instead of the base station distributing fixed time frequency resources for the terminal equipment. That is, the base station only needs to send the access degree probability distribution information to the terminal device, instead of sending a plurality of signaling to indicate the time-frequency resources used by the terminal device for communication, so that the signaling overhead of the system can be reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 illustrates a wireless communication system to which an embodiment of the present invention is applicable.

Fig. 2 is a schematic flow chart of a communication method of one embodiment of the present invention.

Fig. 3 is a schematic diagram of an evolution situation of extrinsic information according to an embodiment of the present invention.

Fig. 4 is a schematic configuration diagram of a factor graph of the embodiment of the present invention.

Fig. 5 is a schematic flow chart of a communication method of another embodiment of the present invention.

Fig. 6 is a schematic flow chart of a communication method of another embodiment of the present invention.

Fig. 7 is a schematic block diagram of a base station of one embodiment of the present invention.

Fig. 8 is a schematic block diagram of a terminal device of one embodiment of the present invention.

Fig. 9 is a schematic block diagram of a base station of another embodiment of the present invention.

Fig. 10 is a schematic block diagram of a terminal device of another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. 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 invention.

Various embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more embodiments. It may be evident, however, that such embodiment(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

As used in this specification, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and/or thread of execution and a component can be localized on one computer and/or distributed between 2 or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate by way of local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from two components interacting with another component in a local system, distributed system, and/or across a network such as the internet with other systems by way of the signal).

Moreover, various aspects or features of the invention may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques. The term "article of manufacture" as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media can include but are not limited to magnetic storage devices (e.g., hard Disk, floppy Disk, magnetic strips, etc.), optical disks (e.g., CD (Compact Disk), DVD (Digital Versatile Disk), etc.), smart cards, and flash Memory devices (e.g., EPROM (Erasable Programmable Read-Only Memory), card, stick, or key drive, etc.). In addition, various storage media described herein can represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" can include, without being limited to, wireless channels and various other media capable of storing, containing, and/or carrying instruction(s) and/or data.

It should be understood that the technical solutions of the embodiments of the present invention can be applied to various communication systems, for example: global System for Mobile communications (GSM) System, Code Division Multiple Access (CDMA) System, Wideband Code Division Multiple Access (WCDMA) System, General Packet Radio Service (GPRS), Long Term Evolution (LTE) System, Frequency Division Duplex (FDD) System, Time Division Duplex (TDD) System, Universal Mobile Telecommunications System (UMTS) System, Worldwide Interoperability for Microwave Access (WiMAX) System, and so on.

It should also be understood that, in the embodiment of the present invention, a Terminal device may be referred to as a User Equipment (UE), and may also be referred to as a Terminal (Terminal), a Mobile Station (MS), a Mobile Terminal (Mobile Terminal), or the like. Alternatively, the terminal device may be a sensor node, an automobile, or other device accessing a communication network, or an apparatus on which a communication network can be accessed for communication. The terminal device may communicate with one or more core networks via a Radio Access Network (RAN), for example, the terminal device may be a mobile phone (or referred to as a "cellular" phone), a computer with a mobile terminal, or the like. The terminal equipment may also be portable, pocket, hand-held, computer-included or vehicle-mounted mobile devices, for example, which exchange voice and/or data with the radio access network.

In the embodiment of the present invention, the Base Station may be a Base Transceiver Station (BTS) in GSM or CDMA, a Base Station (NodeB) in WCDMA, or an evolved Node B (ENB or e-NodeB) in LTE, which is not limited in the present invention.

Fig. 1 illustrates a wireless communication system to which an embodiment of the present invention is applicable. The wireless communication system 100 includes a base station 102, and the base station 102 can include multiple antenna groups. Each antenna group can include one or more antennas, e.g., one antenna group can include

antennas

104 and 106, another antenna group can include

antennas

108 and 110, and an additional group can include

antennas

112 and 114. 2 antennas are shown in fig. 1 for each antenna group, however, more or fewer antennas may be utilized for each group. Base station 102 can additionally include a transmitter chain and a receiver chain, each of which can be implemented as a plurality of components associated with signal transmission and reception (e.g., processors, modulators, multiplexers, demodulators, demultiplexers, antennas, etc.), as will be appreciated by one skilled in the art.

Base station 102 may communicate with one or more terminal devices, such as access terminal 116 and access terminal 122. However, it can be appreciated that base station 102 can communicate with any number of access terminals similar to

access terminals

116 or 122. The

access terminals

116 and 122 can be, for example, cellular phones, smart phones, laptops, handheld communication devices, handheld computing devices, satellite radios, global positioning systems, PDAs, and/or any other suitable device for communicating over the wireless communication system 100. As depicted, access terminal 116 is in communication with

antennas

112 and 114, where

antennas

112 and 114 transmit information to access terminal 116 over forward link 118 and receive information from access terminal 116 over reverse link 120. In addition, access terminal 122 is in communication with

antennas

104 and 106, where

antennas

104 and 106 transmit information to access terminal 122 over forward link 124 and receive information from access terminal 122 over reverse link 126. In an FDD (Frequency Division Duplex) system, forward link 118 may utilize a different Frequency band than that used by reverse link 120, and forward link 124 may utilize a different Frequency band than that used by reverse link 126, for example. Further, in a TDD (Time Division Duplex) system, forward link 118 and reverse link 120 can utilize a common frequency band and forward link 124 and reverse link 126 can utilize a common frequency band.

Each group of antennas and/or the area in which they are designed to communicate is referred to as a sector of base station 102. For example, antenna groups can be designed to communicate to access terminals in a sector of the areas covered by base station 102. During communication of base station 102 with

access terminals

116 and 122 over

forward links

118 and 124, respectively, the transmitting antennas of base station 102 can utilize beamforming to improve signal-to-noise ratio of

forward links

118 and 124. Moreover, while base station 102 utilizes beamforming to transmit to access

terminals

116 and 122 scattered randomly through an associated coverage, mobile devices in neighboring cells can be subject to less interference as compared to a base station transmitting through a single antenna to all its access terminals.

Base station 102, access terminal 116, or access terminal 122 can be a wireless communication transmitting device and/or a wireless communication receiving device at a given time. When sending data, the wireless communication sending device may encode the data for transmission. Specifically, the wireless communication transmitting device may obtain (e.g., generate, receive from other communication devices, or save in memory, etc.) a number of data bits to be transmitted over the channel to the wireless communication receiving device. Such data bits may be contained in a transport block (or transport blocks) of data, which may be segmented to produce multiple code blocks. Further, the wireless communication transmitting apparatus may encode each code block using an encoder (not shown).

It should be understood that the wireless communication system 100 in fig. 1 is only an example, and the communication system to which the embodiment of the present invention is applicable is not limited thereto.

In a large scale access scenario, the number of terminal devices (e.g., access terminal 116 or access terminal 122) communicating with access base station 102 is large and dynamically changing. If the communication resources (e.g., time, frequency, code, etc.) used for communication by each terminal device are predetermined and allocated by the base station, a large amount of signaling overhead is required.

The embodiment of the invention provides a communication method which can reduce the signaling overhead of a system. The communication method of the embodiment of the present invention is described in detail below. It should be noted that these examples are only for helping those skilled in the art to better understand the embodiments of the present invention, and do not limit the scope of the embodiments of the present invention.

Fig. 2 is a schematic flow chart of a communication method of one embodiment of the present invention. The method of fig. 2 may be performed by a base station, such as base station 102 shown in fig. 1.

And 201, determining access degree probability distribution information used in the terminal equipment communication according to system state information, wherein the system state information comprises the total number of users, or at least one of the data volume to be transmitted, the Signal-to-Noise Ratio (SNR) and the Quality of Service (QoS), and the total number of users.

202, sending access degree probability distribution information to the terminal device, where the access degree probability distribution information is used to indicate corresponding probabilities when the terminal device sends data with a specific one or more access degrees respectively.

For example, the access degree probability distribution information includes one or more specific access degrees and corresponding probabilities. And the terminal equipment transmits data to the base station according to the indicated specific access degree and the corresponding probability. Specifically, the access degree probability distribution information may be represented in a table form, or may be represented by a functional expression, which is not limited in the embodiment of the present invention. E.g. access degree distribution function

Wherein d is the access degree, p_dN is the length of the coded bits, for the corresponding probability.

And 203, receiving data transmitted by the terminal equipment according to the access degree probability distribution information.

Further, according to the method of the embodiment of the present invention, since the base station is not required to allocate communication resources to each terminal device in advance. When the total number of users changes, only the probability corresponding to a specific access degree or a plurality of access degrees in the access degree probability distribution information needs to be adjusted, the system design is simple, and the system efficiency is high.

Optionally, as an embodiment, when determining the probability distribution information of the access degrees used by the terminal device during communication according to the system state information, the target average access degree of the terminal device may be determined according to the system state information. And then, determining the probability distribution information of the access degrees used by the terminal equipment in communication according to the target average access degrees.

For example, the base station may determine the average number of accesses of the terminal device according to the total number of users in the system state information. Assuming that the data amount sent by each terminal device is the same, the system load threshold may be divided by the total number of users, and the quotient is used as the target average access degree. Or, the base station may use the quotient value as a reference, and adjust the quotient value as a final target average access degree by combining at least one of the data amount to be transmitted, the signal-to-noise ratio SNR, and the service quality. Therefore, the base station can determine the access degree probability distribution information used by the terminal equipment during communication according to the various information, and further can improve the system performance. If the data volume to be transmitted is large, increasing the quotient value as a target average access degree; or when the service quality requirement is higher, reducing the quotient value as the target average access degree. Variations of the foregoing embodiments that can be anticipated by those skilled in the art are intended to be within the scope of this invention.

Then, the base station may determine the access degree probability distribution information of the terminal device according to the target average access degree. Wherein, M access degrees and their corresponding probabilities included in the access degree probability distribution information satisfy the following two conditions:

and under the condition one, solving the product of each access degree in the M access degrees and the corresponding probability thereof to obtain M products, wherein the sum of the M products is equal to the target average access degree.

And under the second condition, the sum of the probabilities is equal to 1.

In order to describe the embodiments of the present invention more clearly, the foregoing method for determining the probability distribution information of the access degrees is illustrated below, and it should be understood that the scope of the embodiments of the present invention is not limited thereto. Assuming that the target average access degree is 3, the following two kinds of information may be used as the access degree probability distribution information in the embodiment of the present invention:

the first information comprises four access degrees of 0,2,4 and 6, and the corresponding probabilities are 0.3,0.2,0.2 and 0.3 respectively;

the second type of information includes an access degree of 3, corresponding to a probability of 1.

Specifically, when the number of users accessing the system is small, the second information may be selected as the access degree probability distribution information. When the number of users accessing the system is large, the first information can be selected as the probability distribution information of the access degrees.

As another example, the foregoing access degree probability distribution information may be determined in combination with propagation conditions of the external information. Therefore, the system performance can be further improved on the premise of ensuring the system capacity. On one hand, along with the increase of the access degree of the time-frequency resource block, the convergence point of the external information is increased firstly and then is kept unchanged basically. That is, on the premise of ensuring the sparsity of the factor graph, the access degree is increased, and the performance of the system is improved or kept unchanged. On the other hand, when the access probability is greater than a certain threshold, the sparsity of the factor graph is reduced, and the decoding complexity of the base station is increased.

Specifically, it is assumed that the channel gains of the users are the same, and the iteration performance of the extrinsic information is obtained. Fig. 3 is a schematic diagram of an evolution situation of extrinsic information according to an embodiment of the present invention. As shown in fig. 3, the abscissa represents the total access degree of the time-frequency resource block, and the ordinate represents the outer information convergence point. Along with the increase of the total access degree of the time-frequency resource block, the convergence point of the external information quickly tends to be saturated. When the total access degree of the time-frequency resource block is infinite, the convergence point of the external information is progressive performance, and the access probability corresponding to the external information convergence point reaching 99% of the progressive performance is called a saturation point. When the access degree is less than the saturation point, the access degree is increased, the external information convergence point is raised, and the system performance is increased. When the access probability is higher than the saturation point, the access probability is increased, the external information convergence point is basically unchanged, but the complexity of the system is continuously increased. Therefore, the target average access degree can be determined according to the saturation point, and then the probability distribution information of the access degree is determined according to the target average access degree, so that the system capacity and the lower decoding complexity can be ensured.

Optionally, as another embodiment, the base station may further determine the coding rate of the terminal device according to the system throughput requirement. And then, sending the coding rate to the terminal equipment, wherein the coding rate is used for indicating the coding rate used when the terminal equipment carries out coding.

For example, for different SNRs, the base station maximizes the throughput by optimizing the optimal LDPC coding rate, and then transmits the LDPC coding rate to the terminal device. Therefore, the terminal equipment performs LDPC coding based on the code rate, and compared with SCMA (sparse code multiple access), the mechanism does not need to specially design a signature matrix and can achieve the performance similar to that of SCMA.

Optionally, as another embodiment, after receiving the data sent by the terminal device according to the access degree probability distribution information, and when the data sent by the terminal device is successfully decoded, sending feedback information to the terminal device.

For example, after the base station can correctly decode the data sent by the terminal device, that is, after the base station successfully decodes the data sent by the terminal device, the base station sends feedback information to the terminal device. The feedback information may be acknowledgement information. Thus, the terminal device can stop sending data after receiving the feedback information.

The decoding process of the base station is described in detail below with reference to specific examples. It should be noted that these examples are only for helping those skilled in the art to better understand the embodiments of the present invention, and do not limit the scope of the embodiments of the present invention.

Fig. 4 is a schematic configuration diagram of a factor graph of the embodiment of the present invention. The base station adopts an iterative algorithm to decode. Specifically, the base station may perform iterative decoding based on the Factor Graph (Factor Graph) shown in fig. 4, so as to recover the data of each user.

And the base station obtains demodulation information corresponding to each time-frequency resource block through receiving and demodulating. Assuming that m UEs send data on the time-frequency resource block, the base station may form a uniform Tanner graph (one of the factor graphs) according to the linear addition relationship of the m UEs in the access process, the linear superposition relationship of the channels, and the check relationship of the encoder.

As shown in fig. 4, the Tanner graph includes three nodes, a Low Density Parity Check Code (LDPC) Check node (C _ node), an LDPC variable node (V _ node), and a resource block node (RB _ node). Therefore, the base station can complete iterative decoding of the UE 1 to the UE m according to the node information corresponding to the UE 1 to the UE m in the Tanner graph, and finally recover the data of each user.

In the iterative process, the log-Likelihood ratio (LLR) update relationship of the three nodes is given below.

1)C_node:

Let L (c)_ji) Represents the soft information, L (q), output by node j of C _ node to variable node i_ij) Soft information output to other nodes j for variable node i.

L(q_ij)＝α_ij·β_ij (1)

α_ij＝sign[L(q_ij)] (2)

β_ij＝|L(q_ij)| (3)

Then, the relation for updating the C _ node LLR is as shown in equation (4):

wherein the content of the first and second substances,V_jrepresenting the set of all variable nodes connected to check node j.

2)V_node：

The relation for updating the V _ node LLR is shown in equation (5):

3)RB_node：

for each resource block node t, we define a set m (t) of V _ nodes, which is used to represent the set of variable nodes connected to the resource block node t, i.e. m (t) { i | C |_i,t1 }. Then, the symbol received by the receiving end (i.e. the base station) at the resource block node t can be represented as:

wherein h is_i,tFor channel gain, g_i,tIs a weight selected by the user, n_t～N(0,σ²)。

Let L (r)_ti) The node t, which is RB _ node, outputs an LLR value of the node i of V _ node. The updated relationship is shown as follows:

wherein the content of the first and second substances,

according to the updated calculation rule, a user signal iterative decoding recovery algorithm can be constructed. And the base station continuously receives the aliasing data packets sent by the plurality of terminal devices, and simultaneously runs an iterative decoding algorithm to perform multi-user detection and data recovery. After decoding the data successfully transmitted by one terminal device, eliminating the sequence corresponding to the terminal device in the Tanner graph, and transmitting an acknowledgement ACK signal to the terminal device to stop the transmission of the terminal device.

According to the method provided by the embodiment of the invention, the random access of the terminal equipment naturally forms a distributed rateless code, the base station only needs to carry out iterative decoding based on a Tanner graph, the iteration times are reduced, and the decoding complexity of the system is further reduced.

Optionally, as another embodiment, when the access degree probability distribution information is sent to the terminal device, the access degree probability distribution information is sent to the terminal device in a broadcast manner.

For example, in the initialization phase, the base station sends the access degree probability distribution information to each terminal device in a broadcast manner, assuming that the same access degree probability distribution information is used by each user.

Fig. 5 is a schematic flow chart of a communication method of another embodiment of the present invention. The method of fig. 5 may be performed by a terminal device, such as access terminal 116 or access terminal 122 shown in fig. 1.

And 501, receiving access degree probability distribution information used when the terminal equipment communicates from the base station, wherein the access degree probability distribution information is used for indicating corresponding probabilities when the terminal equipment respectively transmits data with one or more specific access degrees.

502, according to the access degree probability distribution information, respectively sending data to be sent to the base station with a specific access degree or a plurality of access degrees and corresponding probabilities.

For example, the probability distribution information of access degrees includes three access degrees d₁,d₂,d₃The corresponding probability is p₁,p₂,p₃. Wherein p is₁+p₂+p ₃1. Thus, the terminal device respectively uses the three access degrees d₁,d₂,d₃And transmitting data to the base station, wherein the number of times of transmitting the data at each access degree is determined according to the corresponding probability.

Suppose that the terminal device sends 10 times data, p, to the base station₁0.3, the terminal device has access degree d in 10 times₁The number of times of transmitting data is 3, and the position of the 3 times in 10 transmissions is not limited. In addition, if one of the three access degrees is zero, it indicates that the terminal device does not transmit the numberAccordingly.

Optionally, as an embodiment, before sending data to be sent to the base station according to the access degree probability distribution information and with a specific access degree or multiple access degrees and corresponding probabilities, an encoding code rate is received from the base station, where the encoding code rate is determined by the base station according to the system throughput requirement. And then, coding the data to be transmitted by taking the coding rate as a fixed code rate to obtain coding bits. And finally, modulating the coded bits to obtain a modulation symbol sequence.

Optionally, as another embodiment, when sending data to be sent to the base station with a specific one or more access degrees and corresponding probabilities respectively according to the access degree probability distribution information, the terminal device may determine, according to the access degree probability distribution information, the access degrees d when sending the data this time, where d is a non-negative integer. Then, d symbols are selected from the modulation symbol sequence to be linearly added, and the result of the linear addition is transmitted to the base station.

Thus, the random access of the terminal device naturally forms a distributed rateless code, and the system can adaptively approach the channel capacity.

It is to be understood that linear addition includes both direct addition and weighted addition. If the terminal device uses a weighted addition method, the weights can be used to influence the previously described Tanner graph, so that the Tanner graph is more sparse, and the convergence of iterative decoding is accelerated.

For example, the terminal device encodes data using LDPC, resulting in encoded bits. The coded bits are then symbol mapped to obtain a series of modulation symbols. And the terminal equipment determines the access degree d when the data is sent according to the access degree probability distribution information. Then, d symbols are selected from the aforementioned modulation symbols and linearly added. And finally, the symbols after the linear addition are sent to a base station through time-frequency resources occupied by the system. And the terminal equipment repeats the process of determining the access degree and transmitting the modulation symbols with corresponding lengths until the data transmission is finished.

Optionally, as another embodiment, after the data to be transmitted is respectively transmitted to the base station according to the access point number probability distribution information with the specific one or more access points numbers and the corresponding probabilities, when the feedback information is received from the base station, the data to be transmitted is stopped being transmitted to the base station.

Fig. 6 is a schematic flow chart of a communication method of another embodiment of the present invention. The communication method of the embodiment of the present invention is further described below with reference to fig. 6. It should be noted that these examples are only for helping those skilled in the art to better understand the embodiments of the present invention, and do not limit the scope of the embodiments of the present invention.

As shown in fig. 6, UE 1, UE 2, …, UE M access the base station for communication. Data to be transmitted of UE 1 is

Length of K₁And inputting the bits into an encoder to be encoded to obtain encoded bits. Carrying out symbol mapping on the coded bits to obtain a series of modulation symbols

The degree generator determines the degree d of the current transmission according to the access degree probability distribution information received from the access degree probability distribution controller at the base station side₁. Data selector MUX from modulation symbols

In selection of d₁And inputting the symbols into an adder sigma to perform linear addition, and finally transmitting the symbols to a channel time frequency resource block. UE 1 repeats the above process until the data to be transmitted is successfully transmitted

Similarly, the data to be transmitted of UE M is

Length of K_MAnd inputting the bits into a code to be coded to obtain coded bits. The coded bits are symbol mapped to obtain a series of modulation symbols

Length N_MA bit. The degree generator determines the degree d of the current transmission according to the access degree probability distribution information received from the access degree probability distribution controller at the base station side_MThe data selector MUX selects from the modulation symbols

In selection of d_MAnd inputting the symbols into an adder sigma to perform linear addition, and finally transmitting the symbols to a channel time frequency resource block. UE M repeats the above process until the modulation symbol is successfully transmitted

And the access degree probability distribution controller of the base station determines the access degree probability distribution information and sends the corresponding access degree probability distribution information to the degree generator of each UE. And the base station demodulates the data received from the UE to obtain demodulation information corresponding to each time-frequency resource block. Then, a unified factor graph (e.g., Tanner graph) is formed according to the check relationship of the encoder, the linear addition relationship of each UE access process and the linear superposition relationship of the channels, and iterative multi-user detection decoding is performed on the factor graph. When the base station successfully decodes the message of one UE, an acknowledgement message is sent to the UE. At the same time, the current received sequence for that user is eliminated from the factor graph. Therefore, the base station carries out iterative decoding based on a factor graph, and does not need complex multi-user detection and SISO decoder iterative process, thereby reducing the decoding complexity.

Fig. 7 is a schematic block diagram of a base station of one embodiment of the present invention. The base station in fig. 7 includes a determination unit 701, a transmission unit 702, and a reception unit 703.

A determining unit 701, configured to determine, according to system state information, access degree probability distribution information used during communication of a terminal device, where the system state information includes a total number of users, or at least one of a data amount to be transmitted, a signal-to-noise ratio (SNR), and a quality of service (QoS), and the total number of users.

A sending unit 702, configured to send, to the terminal device, access degree probability distribution information, where the access degree probability distribution information is used to indicate probabilities corresponding to when the terminal device sends data with a specific one or multiple access degrees respectively.

For example, the access degree probability distribution information includes one or more specific access degrees and corresponding probabilities. The terminal equipment being specified in accordance with the indicationAnd sending the data to the base station by the access degree and the corresponding probability. Specifically, the access degree probability distribution information may be represented in a table form, or may be represented by a functional expression, which is not limited in the embodiment of the present invention. E.g. access degree distribution function

A receiving unit 703 is configured to receive data sent by the terminal device according to the access degree probability distribution information.

Optionally, as an embodiment, the determining unit 701 is specifically configured to determine the target average access degree of the terminal device according to the system state information. And then, determining the probability distribution information of the access degrees used by the terminal equipment in communication according to the target average access degrees.

And under the second condition, the sum of the probabilities is equal to 1.

Optionally, as another embodiment, the determining unit 701 is further configured to determine an encoding code rate of the terminal device according to the system throughput requirement. The sending unit 702 is further configured to send, to the terminal device, an encoding code rate, where the encoding code rate is used to indicate an encoding code rate used when the terminal device performs encoding.

Optionally, as another embodiment, the sending unit 702 is further configured to send feedback information to the terminal device when the data sent by the terminal device is successfully decoded.

For example, after the base station can correctly decode the data sent by the terminal device, that is, after the base station successfully decodes the data sent by the terminal device, the base station sends feedback information to the terminal device. The feedback information may be acknowledgement information. Thus, the terminal device can stop sending data after receiving the feedback information. The decoding process of the base station can refer to the description of fig. 3, and is not described herein again to avoid repetition.

Optionally, as another embodiment, the sending unit 702 is specifically configured to send the access degree probability distribution information to the terminal device in a broadcast manner.

Fig. 8 is a schematic block diagram of a terminal device of one embodiment of the present invention. The terminal device in fig. 8 includes a receiving unit 801 and a transmitting unit 802.

A receiving unit 801, configured to receive, from a base station, access degree probability distribution information used when a terminal device communicates, where the access degree probability distribution information is used to indicate probabilities corresponding to when the terminal device transmits data with a specific one or multiple access degrees, respectively.

For example, the access degree probability distribution information includes one or more specific access degrees and corresponding probabilities. And the terminal equipment transmits data to the base station according to the indicated specific access degree and the corresponding probability. Specifically, the access degree probability distribution information may be represented in a table form, or may be represented by a functional expression, which is not limited in the embodiment of the present invention. E.g. access degree distribution functionWherein d is the access degree, p_dIs corresponding toProbability, N, is the length of the coded bits.

A sending unit 802, configured to send data to be sent to a base station according to the access degree probability distribution information and with a specific access degree or multiple access degrees and corresponding probabilities.

Suppose that the terminal device sends 10 times data, p, to the base station₁0.3, the terminal device has access degree d in 10 times₁The number of times of transmitting data is 3, and the position of the 3 times in 10 transmissions is not limited. In addition, if one of the three access degrees is zero, it indicates that the terminal device does not transmit data.

Optionally, as an embodiment, the terminal device further includes a coding unit 803 and a modulation unit 804. The receiving unit 801 is further configured to receive an encoding code rate from the base station, where the encoding code rate is determined by the base station according to the system throughput requirement. In this case, the encoding unit 803 is configured to encode the data to be transmitted with the encoding rate as the fixed rate to obtain encoded bits. And the modulation unit is used for modulating the coded bits to obtain a modulation symbol sequence.

Optionally, as an embodiment, the sending unit 802 is specifically configured to determine, according to the access degree probability distribution information, the access degree d when data is sent this time, where d is a non-negative integer. Then, d symbols are selected from the modulation symbol sequence to be linearly added, and the result of the linear addition is transmitted to the base station. Thus, the random access of the terminal device naturally forms a distributed rateless code, and the system can adaptively approach the channel capacity. It is to be understood that linear addition includes both direct addition and weighted addition. If the terminal device uses a weighted addition method, the weights can be used to influence the previously described Tanner graph, so that the Tanner graph is more sparse, and the convergence of iterative decoding is accelerated.

Optionally, as another embodiment, the sending unit 802 is further configured to stop sending data to be sent to the base station when the terminal device receives the feedback information from the base station.

The base station 90 of fig. 9 may be used to implement the steps and methods of the above-described method embodiments. In the embodiment of fig. 9, the base station 90 comprises an antenna 901, a transmitter 902, a receiver 903, a processor 904 and a memory 905. Processor 904 controls the operation of base station 90 and may be used to process signals. Memory 905 may include both read-only memory and random access memory, and provides instructions and data to processor 904. The transmitter 902 and receiver 903 may be coupled to an antenna 901. The various components of the base station 90 are coupled together by a bus system 909, wherein the bus system 909 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are labeled in the figure as bus system 909. For example, the base station 90 may be the base station 102 shown in fig. 1.

In particular, the memory 905 may store instructions to perform the following processes:

Optionally, as an embodiment, the memory 905 may also store instructions to perform the following processes:

when determining the access degree probability distribution information used during the communication of the terminal equipment according to the system state information, determining the target average access degree of the terminal equipment according to the system state information; and determining the access degree probability distribution information used by the terminal equipment during communication according to the target average access degree.

and after receiving the data transmitted by the terminal equipment according to the access degree probability distribution information, when the data transmitted by the terminal equipment is successfully decoded, transmitting feedback information to the terminal equipment.

and when the access degree probability distribution information is sent to the terminal equipment, the access degree probability distribution information is sent to the terminal equipment in a broadcasting mode.

The terminal device 100 of fig. 10 may be used to implement the steps and methods in the above-described method embodiments. In the embodiment of fig. 10, terminal device 100 includes an antenna 1001, a transmitter 1002, a receiver 1003, a processor 1004, and a memory 1005. The processor 1004 controls the operation of the terminal device 100 and may be used to process signals. Memory 1005, which may include both read-only memory and random-access memory, provides instructions and data to processor 1004. The transmitter 1002 and receiver 1003 may be coupled to an antenna 1001. The various components of the terminal device 100 are coupled together by a bus system 1009, where the bus system 1009 includes a power bus, a control bus, and a status signal bus in addition to a data bus. But for clarity of illustration the various buses are labeled in the figure as bus system 1009. For example, terminal device 100 may be access terminal 116 or access terminal 122 shown in fig. 1.

In particular, the memory 1005 may store instructions that perform the following process:

receiving access degree probability distribution information used when the terminal equipment communicates from a base station, wherein the access degree probability distribution information is used for indicating the corresponding probability when the terminal equipment respectively sends data with one or more specific access degrees;

Optionally, as an embodiment, the memory 1005 may also store instructions to perform the following process:

and modulating the coded bits to obtain a modulation symbol sequence.

according to the access degree probability distribution information, when data to be sent are sent to a base station respectively according to one or more specific access degrees and corresponding probabilities, the access degrees d in the data sending process are determined according to the access degree probability distribution information, and d is a non-negative integer; d symbols are selected from the modulation symbol sequence to be linearly added, and the result of the linear addition is sent to the base station.

after respectively sending data to be sent to the base station according to the access degree probability distribution information and the specific access degree or the specific access degrees and the corresponding probability, stopping sending the data to be sent to the base station when the feedback information is received from the base station.

It should be understood that, in various embodiments of the present invention, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention essentially or partially contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

A method of communication, the method comprising:

determining access degree probability distribution information used during communication of terminal equipment according to system state information, wherein the system state information comprises the total number of users, or at least one of data volume to be transmitted, signal-to-noise ratio (SNR) and quality of service (QoS), and the total number of users;

sending the access degree probability distribution information to the terminal equipment, wherein the access degree probability distribution information is used for indicating the corresponding probability when the terminal equipment sends data respectively with one or more specific access degrees;

and receiving data sent by the terminal equipment according to the access degree probability distribution information.
The method of claim 1, wherein the determining, according to the system state information, the access degree probability distribution information used by the terminal device in communication comprises:

determining the target average access degree of the terminal equipment according to the system state information;

and determining the probability distribution information of the access degrees used by the terminal equipment during communication according to the target average access degrees.
The method according to claim 1 or 2, characterized in that the method further comprises:

determining the coding rate of the terminal equipment according to the system throughput rate requirement;

and sending the coding rate to the terminal equipment, wherein the coding rate is used for indicating the coding rate used when the terminal equipment carries out coding.
The method according to any one of claims 1 to 3, wherein after the receiving the data transmitted by the terminal device according to the access degree probability distribution information, the method further comprises:

and when the data sent by the terminal equipment is decoded successfully, sending feedback information to the terminal equipment.
The method according to any one of claims 1 to 4, wherein the sending the access degree probability distribution information to the terminal device comprises:

and sending the access degree probability distribution information to the terminal equipment in a broadcasting mode.
A method of communication, the method comprising:

receiving access degree probability distribution information used when terminal equipment communicates from a base station, wherein the access degree probability distribution information is used for indicating corresponding probabilities when the terminal equipment respectively sends data with one or more specific access degrees;

and according to the access degree probability distribution information, respectively sending data to be sent to the base station according to the specific one or more access degrees and the corresponding probability.
The method according to claim 6, wherein before the sending data to be sent to the base station with the specific one or more access degrees and corresponding probabilities respectively according to the access degree probability distribution information, the method further comprises:

receiving a coding rate from a base station, wherein the coding rate is determined by the base station according to the system throughput rate requirement;

taking the coding rate as a fixed rate, and coding the data to be sent to obtain a coding bit;

and modulating the coded bits to obtain a modulation symbol sequence.
The method of claim 7, wherein the sending data to be sent to the base station according to the probability distribution information of the access degrees with the specific one or more access degrees and corresponding probabilities respectively comprises:

determining the access degree d when the data is sent according to the access degree probability distribution information, wherein the d is a non-negative integer;

and d symbols are selected from the modulation symbol sequence to be subjected to linear addition, and the result of the linear addition is sent to the base station.
The method according to any one of claims 6 to 8, wherein after transmitting data to be transmitted to the base station according to the access degree probability distribution information with the specific one or more access degrees and corresponding probabilities, respectively, the method further comprises:

and when receiving the feedback information from the base station, stopping sending the data to be sent to the base station.
A base station, characterized in that the base station comprises:

a determining unit, configured to determine, according to system state information, access degree probability distribution information used during communication of a terminal device, where the system state information includes a total number of users, or at least one of a data amount to be transmitted, a signal-to-noise ratio (SNR), and a quality of service (QoS), and the total number of users;

a sending unit, configured to send the access degree probability distribution information to the terminal device, where the access degree probability distribution information is used to indicate probabilities corresponding to when the terminal device sends data with a specific one or multiple access degrees respectively;

and the receiving unit is used for receiving the data sent by the terminal equipment according to the access degree probability distribution information.
Base station according to claim 10, characterized in that the determination unit is specifically configured to,

determining the target average access degree of the terminal equipment according to the system state information;

and determining the probability distribution information of the access degrees used by the terminal equipment during communication according to the target average access degrees.
The base station according to claim 10 or 11,

the determining unit is further configured to determine an encoding rate of the terminal device according to a system throughput rate requirement;

the sending unit is further configured to send the coding rate to the terminal device, where the coding rate is used to indicate a coding rate used when the terminal device performs coding.
The base station according to any of claims 10 to 12, wherein the sending unit is further configured to send feedback information to the terminal device when the data sent by the terminal device is successfully decoded.
The base station according to any of claims 10 to 13, wherein the sending unit is specifically configured to send the access degree probability distribution information to the terminal device by means of broadcasting.
A terminal device, characterized in that the terminal device comprises:

a receiving unit, configured to receive, from a base station, access degree probability distribution information used when the terminal device communicates, where the access degree probability distribution information is used to indicate probabilities corresponding to when the terminal device transmits data with a specific one or multiple access degrees, respectively;

and a sending unit, configured to send, according to the access degree probability distribution information, to the base station, the data to be sent according to the specific one or more access degrees and the corresponding probabilities.
The terminal device of claim 15, wherein the terminal device further comprises a coding unit and a modulation unit,

the receiving unit is further configured to receive a coding rate from a base station, where the coding rate is determined by the base station according to a system throughput rate requirement;

the encoding unit is configured to encode the data to be sent with the encoding rate as a fixed rate to obtain an encoded bit;

and the modulation unit is used for modulating the coded bits to obtain a modulation symbol sequence.
The terminal device according to claim 16, wherein the sending unit is specifically configured to,

determining the access degree d when the data is sent according to the access degree probability distribution information, wherein the d is a non-negative integer;

and d symbols are selected from the modulation symbol sequence to be subjected to linear addition, and the result of the linear addition is sent to the base station.
The terminal device according to any one of claims 15 to 17, wherein the sending unit is further configured to stop sending the data to be sent to the base station when the terminal device receives feedback information from the base station.