Communication method and related device

Abstract

The invention provides a communication method and a related device. The complexity of geometric forming can be reduced. The method comprises the following steps: a first device obtains a bit sequence to be transmitted, and modulates the bit sequence based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol; and the first device sends the modulation symbol to the second device, and correspondingly, the second device receives the modulation symbol and demodulates the modulation symbol to obtain the bit sequence. Wherein a plurality of constellation points in the third constellation point set are non-uniformly distributed, the third constellation point set is similar to a first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of a second constellation point set, and the second constellation point set is a set of a plurality of constellation points corresponding to a predefined second modulation scheme; the order of the second modulation scheme is higher than that of the first modulation scheme, and the order of the third modulation scheme is the same as that of the first modulation scheme.

Description

Communication method and related device Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method and related devices. Background Art

[0002] High-order modulation is a common technique in mobile communication systems. By mapping multiple bits onto the same symbol and transmitting them across the channel, high-order modulation can further improve spectral efficiency. Information theory analysis shows that for systems with limited average power, channel capacity can be further increased by optimizing the distribution of constellation points, a technique known as shaping. Intuitively, since different symbols in high-order modulation have different energies, transmitting more low-energy symbols and fewer high-energy symbols can reduce the average power of the transmitted signal and improve performance gains.

[0003] Currently, these goals can be achieved using either geometric shaping or probabilistic shaping. While probabilistic shaping offers a relatively greater performance gain, it significantly alters the coded modulation process. Geometric shaping, on the other hand, makes relatively minor changes to the coding process, thus achieving a certain performance gain at the cost of less implementation complexity.

[0004] However, geometric forming involves irregular constellation points and the optimal construction of constellations, so the description of geometric forming is highly complex.

[0005] Summary of the Invention

[0006] The present application provides a communication method and related devices to reduce the complexity of geometric forming.

[0007] In a first aspect, the present application provides a communication method. The method can be applied to a first device. For example, the method can be executed by the first device, or by a component configured in the first device (such as a chip, a chip system, etc.), or by a logic module or software that can implement all or part of the functions of the first device, which is not limited by the present application.

[0008] Exemplarily, the method includes: obtaining a bit sequence to be transmitted; modulating the bit sequence based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol; the multiple constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to a first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of the second constellation point set, the second constellation point set is a set of multiple constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme.

[0009] It should be understood that the uneven distribution of the multiple constellation points in the third constellation point set can be understood as follows: every two adjacent constellation points in any coordinate direction in the third constellation point set are regarded as a group of adjacent constellation points, and there are at least two groups of adjacent constellation points in the third constellation point set with different inter-constellation point distances.

[0010] The similarity between the third constellation point set and the first constellation point set can be understood as follows: the number of constellation points included in the third constellation point set is the same as the number of constellation points included in the first constellation point set; the number of constellation points located in the same coordinate direction in the third constellation point set and the first constellation point set is the same; if every two adjacent constellation points located in the same constellation point set in the same coordinate direction are regarded as a group of adjacent constellation points, and the ratio of the distance between the group of adjacent constellation points located at the first position in the first constellation point set to the distance between the group of adjacent constellation points located at the first position in the third constellation point set is the same as the ratio of the distance between the group of adjacent constellation points located at the second position in the first constellation point set to the distance between the group of adjacent constellation points located at the second position in the third constellation point set.

[0011] It should also be understood that the multiple constellation points in the second constellation point set can be evenly distributed. In other words, if every two adjacent constellation points in any coordinate direction in the second constellation point set are regarded as a group of adjacent constellation points, the inter-constellation point distances of any two groups of adjacent constellation points in the second constellation point set can be the same.

[0012] In this application, because the multiple constellation points in the third constellation point set are non-uniformly distributed and similar to the first constellation point set, and the first constellation point set is a subset of the second constellation point set, the bit sequence to be transmitted is modulated by the third modulation scheme and mapped to the constellation points in the third constellation point set. This is equivalent to performing geometric shaping, thereby achieving shaping gain. Furthermore, because the first constellation point set is a subset of the predefined second constellation point set, this solution only requires defining a single constellation point extraction method to derive the first constellation point set, and thus the third constellation point set, from the predefined constellation point set, thereby reducing implementation complexity.

[0013] In a second aspect, the present application provides a communication method. This method can be applied to a second device. For example, it can be executed by the second device, or it can be executed by a component configured in the second device (such as a chip, chip system, etc.), or it can be implemented by a logic module or software that can implement all or part of the functions of the second device, which is not limited by this application.

[0014] Exemplarily, the method includes: receiving a modulation symbol, where the modulation symbol is obtained by mapping a bit sequence to each constellation point in a third constellation point set based on a third modulation scheme; the multiple constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to a first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of the second constellation point set, the second constellation point set is a set of multiple constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme; and demodulating the modulation symbol to obtain the bit sequence.

[0015] The description of the first constellation point set and the second constellation point set may refer to the first aspect and will not be repeated here.

[0016] In this application, because the multiple constellation points in the third constellation point set are non-uniformly distributed and similar to the first constellation point set, and the first constellation point set is a subset of the second constellation point set, the bit sequence to be transmitted is modulated by the third modulation scheme and mapped to the constellation points in the third constellation point set. This is equivalent to performing geometric shaping, thereby achieving shaping gain. Furthermore, because the first constellation point set is a subset of the predefined second constellation point set, this solution only requires defining a single constellation point extraction method to derive the first constellation point set from the predefined constellation point set, thus reducing implementation complexity.

[0017] In combination with the first aspect and the second aspect, in some implementations, the third constellation point set is the same as the first constellation point set.

[0018] In combination with the first aspect and the second aspect, in some implementations, the position of each constellation point in the constellation point set corresponding to the first modulation scheme is determined by a first mapping relationship, and the first mapping relationship indicates multiple modulation schemes and the position of the constellation point corresponding to each modulation scheme, and the multiple modulation schemes include the first modulation scheme.

[0019] It should be understood that the multiple modulation schemes may include multiple modulation schemes with the same modulation order, or may include multiple modulation schemes with different modulation orders. The multiple constellation points included in the constellation point set corresponding to each modulation scheme in the multiple modulation schemes may be uniformly distributed or non-uniformly distributed.

[0020] Exemplarily, the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point.

[0021] Since the first mapping relationship includes a correspondence between multiple modulation schemes and multiple position coordinate sets, the first device can determine a position coordinate set corresponding to the first modulation scheme from multiple position coordinate sets based on the first modulation scheme and the first mapping relationship. The multiple constellation points identified by the position coordinate set are the constellation points in the first constellation point set.

[0022] Exemplarily, each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

[0023] Due to the correspondence between multiple modulation schemes and multiple sequence number sets in the first mapping relationship, the first device can determine a sequence number set corresponding to the first modulation scheme from multiple sequence number sets based on the first modulation scheme and the first mapping relationship, and the constellation point identified by each sequence number in the sequence number set belongs to the first constellation point set.

[0024] In combination with the first aspect and the second aspect, in certain implementations, among the multiple modulation schemes, the multiple constellation points in the constellation point set corresponding to each modulation scheme are symmetric about the origin.

[0025] In combination with the first aspect and the second aspect, in some implementations, the second modulation scheme is 1024 quadrature amplitude modulation (QAM) or other orders of QAM.

[0026] In a third aspect, the present application provides a communication method. This method can be applied to a first device. For example, it can be executed by the first device, or it can be executed by a component configured in the first device (such as a chip, chip system, etc.), or it can be implemented by a logic module or software that can implement all or part of the functions of the first device, which is not limited by this application.

[0027] Exemplarily, the method includes: receiving indication information, wherein the indication information is used to indicate the use of parameters in a first modulation and coding scheme (MCS) table or a second MCS table for encoding and modulation; based on the indication information, determining the use of the first MCS table or the second MCS table for encoding and modulating the information bit sequence to be transmitted.

[0028] It should be understood that the first MCS table in the present application is designed for geometric shaping or probability shaping. Therefore, when the corresponding shaping technology is adopted, the transmission performance of the first MCS table is better than the transmission performance of the second MCS table.

[0029] In combination with the third aspect, in some implementations, the method further includes: encoding and modulating the information bit sequence using parameters in the first MCS table or the second MCS table to obtain modulation symbols; and sending the modulation symbols.

[0030] Fourthly, the present application provides a communication method. This method can be applied to a second device. For example, it can be executed by the second device, or it can be executed by a component configured in the second device (such as a chip, chip system, etc.), or it can be implemented by a logic module or software that can implement all or part of the functions of the second device, which is not limited by this application.

[0031] Exemplarily, the method includes: generating indication information, where the indication information is used to indicate that encoding and modulation are performed using parameters in the MCS table or the second MCS table; and sending the indication information.

[0032] For the description of the first MCS table and the second MCS table, please refer to the third aspect and will not be repeated here.

[0033] In combination with the fourth aspect, in some implementations, the method also includes: receiving modulation symbols, where the modulation symbols are obtained by encoding and modulating the information bit sequence to be transmitted using parameters in the first MCS table or the second MCS table; and demodulating and decoding the modulated symbols to obtain the information bit sequence.

[0034] In combination with the third aspect and the fourth aspect, in some implementations, there are different modulation orders in the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0035] For example, in the first MCS table, the switching point where the modulation order switches from 2 to 4 is MCS index 8, and the switching point where the modulation order switches from 4 to 6 is MCS index 14; in the second MCS table, the switching point where the modulation order switches from 2 to 4 is MCS index 10, and the switching point where the modulation order switches from 4 to 6 is MCS index 17.

[0036] In combination with the third aspect and the fourth aspect, in some implementations, there are different modulation orders in the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0037] For example, in the second MCS table, the switching point where the modulation order switches from 2 to 4 is the spectrum efficiency 1.3281, and the switching point where the modulation order switches from 4 to 6 is the spectrum efficiency 2.5664. In the first MCS table, the switching point where the modulation order switches from 2 to 4 is the spectrum efficiency 1.1758, and the switching point where the modulation order switches from 4 to 6 is the spectrum efficiency 2.1621.

[0038] It can be seen that the modulation order switching point in the first MCS table is earlier than the modulation order switching point in the second MCS table.

[0039] In a fifth aspect, the present application provides a communication device, comprising modules or units for implementing the method in any of the above aspects and any possible implementation of any aspect. It should be understood that each module or unit can implement the corresponding function by executing a computer program.

[0040] In a sixth aspect, the present application provides another communication device, comprising a processor, wherein the processor is configured to execute the method described in any aspect and any possible implementation of any aspect.

[0041] The apparatus may further include a memory for storing instructions and data. The memory is coupled to the processor, and when the processor executes the instructions stored in the memory, the method described in the above aspects may be implemented.

[0042] The apparatus may further include a communication interface, where the communication interface is used for the apparatus to communicate with other devices. Exemplarily, the communication interface may be a transceiver, a circuit, a bus, a module, or other types of communication interfaces.

[0043] In the seventh aspect, the present application provides a chip system comprising at least one processor for supporting the implementation of the functions involved in any of the above aspects and any possible implementation of any aspect, for example, receiving or processing the data and / or information involved in the above method.

[0044] In one possible design, the chip system further includes a memory, which is used to store program instructions and data, and the memory is located inside or outside the processor.

[0045] The chip system can be composed of chips, or can include chips and other discrete devices.

[0046] In an eighth aspect, the present application provides a computer-readable storage medium comprising a computer program, which, when executed on a computer, enables the computer to implement the method in any of the above aspects and any possible implementation of any aspect.

[0047] In a ninth aspect, the present application provides a computer program product, comprising: a computer program (also referred to as code, or instructions), which, when executed, enables a computer to execute a method in any aspect and any possible implementation of any aspect.

[0048] In a tenth aspect, the present application provides a communication system comprising the aforementioned first device and second device.

[0049] It should be understood that the fifth to tenth aspects of the present application correspond to the technical solutions of the first to fourth aspects of the present application, and the beneficial effects achieved by each aspect and the corresponding feasible implementation methods are similar and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] FIG1 is a schematic diagram of the architecture of a communication system applicable to the method provided in an embodiment of the present application;

[0051] FIG2 is a schematic diagram of a signal processing process provided in an embodiment of the present application;

[0052] FIG3 is a schematic diagram of the distribution of constellation points of QAM modulation;

[0053] FIG4 is a schematic diagram showing the distribution of constellation points of APSK modulation;

[0054] 5 and 6 are schematic flow charts of the communication method provided in the embodiments of the present application;

[0055] 7 and 8 are schematic block diagrams of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] The technical solution in this application will be described below with reference to the accompanying drawings.

[0057] The technical solutions provided in this application can be applied to various communication systems, such as: long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, sidelink (SL) communication system, world-wide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) mobile communication system or new radio access technology (NR), satellite communication system, etc. Among them, the 5G mobile communication system can include non-standalone (NSA) and / or standalone (SA) networking.

[0058] The technical solution provided in this application can also be applied to future communication systems, such as the sixth generation (6G) mobile communication system, etc. This application does not limit this.

[0059] The technical solution provided in this application can also be applied to business scenarios including backscatter communication and passive IoT communication in NR communication systems.

[0060] In this application, a radio access network (RAN) device is a device with wireless transceiver capabilities. It can provide wireless communication services and connect terminals to a wireless network. It can be a node in a radio access network, referred to as a RAN node.

[0061] In one possible scenario, a RAN node can be a base station (BS), an evolved NodeB (eNodeB), a transmission reception point (TRP), a home evolved NodeB (HNB), a wireless fidelity (Wi-Fi) access point (AP), a mobile switching center, a next-generation NodeB (gNB) in a 5G mobile communication system, a next-generation NodeB in a 6G mobile communication system, or a base station in a future mobile communication system. A RAN node can also be a device that performs base station functions in device-to-device (D2D) communication systems, vehicle-to-everything (V2X) communication systems, machine-to-machine (M2M) communication systems, and Internet of Things (IoT) communication systems. A RAN node can also be a RAN node in a non-terrestrial network (NTN), meaning that the RAN node can be deployed on a high-altitude platform or satellite. A RAN node can be a macro base station, a micro base station, an indoor base station, a relay node, a donor node, or a radio controller in a cloud radio access network (CRAN) scenario, or a node in an open radio access network (O-RAN or ORAN) scenario. Alternatively, a RAN node can be a server, a wearable device, a vehicle, or an onboard device. For example, a RAN node in V2X technology can be a roadside unit (RSU). Of course, a RAN node can also be a node in the core network.

[0062] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, and different RAN nodes respectively implement part of the functions of the base station. For example, the RAN node can be a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). The CU and DU can be set separately, or they can be included in the same network element, such as a baseband unit (BBU). The RU can be included in a radio frequency device or radio frequency unit, such as a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH).

[0063] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meanings. For example, in the ORAN system, CU may be referred to as Open CU (O-CU), DU may be referred to as Open DU (O-DU), CU-CP may be referred to as Open CU-CP (O-CU-CP), CU-UP may be referred to as Open CU-UP (O-CU-UP), and RU may be referred to as Open RU (O-RU).

[0064] Any of the CU (or CU-CP, CU-UP), DU, and RU units may be implemented as software modules, hardware modules, or a combination of software and hardware modules. That is, the wireless access network device in this application may be a virtualized device, for example, implemented as general-purpose hardware and instantiated virtualization functions, or as dedicated hardware and instantiated virtualization functions. The general-purpose hardware may be a server, such as a cloud server.

[0065] The terminal device in this application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device.

[0066] The terminal device may be a device that provides voice / data connectivity to users, such as a handheld device or vehicle-mounted device with wireless connection function. At present, some examples of terminal devices may include: mobile phones, tablet computers, computers with wireless transceiver functions (such as laptops, PDAs, etc.), mobile internet devices (MIDs), virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self-driving, drones, wireless terminals in remote medical care, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication functions, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, terminal devices in 5G networks or future evolved public land mobile communication networks (PLMNs). Mobile network, PLMN) terminal equipment, etc.

[0067] Wearable devices, also known as wearable smart devices, are a general term for wearable devices that use wearable technology to intelligently design and develop wearable devices for daily wear, such as glasses, gloves, watches, clothing, and shoes. Wearable devices are portable devices that are worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not just hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. In a broad sense, wearable smart devices include those that are fully functional, large in size, and can achieve full or partial functions without relying on smartphones, such as smart watches or smart glasses, as well as those that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various smart bracelets and smart jewelry for vital sign monitoring.

[0068] Furthermore, terminal devices can also be end devices in IoT systems. IoT is a crucial component of future information technology development. Its primary technical feature is connecting objects to the internet through communication technologies, thereby enabling intelligent networks that interconnect humans and machines, and objects and things. IoT technology, for example, utilizes narrowband (NB) technology to achieve massive connectivity, deep coverage, and power-saving terminals.

[0069] Terminal devices can also include sensors such as smart printers, train detectors, and gas stations. Their main functions include collecting data (part of the terminal equipment), receiving control information and downlink data from network devices, and sending electromagnetic waves to transmit uplink data to network devices.

[0070] The terminal device may be a virtualized device, for example, implemented by general-purpose hardware and instantiated virtualization functions, or by dedicated hardware and instantiated virtualization functions. The general-purpose hardware may be a server, for example, a cloud server.

[0071] The terminal device can be a passive terminal device with an envelope detection receiver, a passive IoT terminal device, a semi-passive terminal device, a semi-passive IoT terminal device, a terminal device with backscattering capability, an NR terminal device, an NR base station / pole station / micro station / small station, a reader / writer terminal device, etc.

[0072] It should be understood that the present application does not limit the specific forms of the wireless access network device and the terminal device.

[0073] Figure 1 is a schematic diagram of the architecture of a communication system 1000 applicable to the method provided in an embodiment of the present application. As shown in Figure 1 , the communication system 1000 includes a radio access network 10 and a core network 20. Optionally, the communication system 1000 may also include the Internet 30. The radio access network 10 may include at least one radio access network device (such as 110a and 110b in Figure 1 ) and at least one terminal (such as 120a-120j in Figure 1 ).

[0074] Terminals can connect to radio access network equipment wirelessly, and radio access network equipment can connect to the core network wirelessly or via wired connections. Core network equipment and radio access network equipment can be independent, distinct physical devices, or they can integrate the core network equipment's functions and the radio access network equipment's logical functions into the same physical device. Alternatively, a single physical device can integrate some core network equipment functions and some radio access network equipment functions. Terminals and radio access network equipment can connect to each other via wired or wireless connections.

[0075] Wireless access network devices and terminals, wireless access network devices, and terminals can communicate through authorized spectrum, unauthorized spectrum, or both. They can communicate through spectrum below 6 gigahertz (GHz), spectrum above 6 GHz, or both. The embodiments of this application do not limit the spectrum resources used for wireless communications.

[0076] The wireless access network device may be a base station deployed in the air, such as a satellite base station 110a; or a base station deployed indoors, such as a micro base station or an indoor station 110b.

[0077] The terminal can be a terminal deployed in the air, such as the helicopter or drone 120i in Figure 1; it can also be a terminal deployed on the ground, such as the mobile phones 120a, 120e, 120f and 120j, vehicle 120b, computer 120g, printer 120h, etc. in Figure 1.

[0078] Wireless access network equipment and terminals can be fixed or mobile. For example, they can be deployed on land, indoors or outdoors, handheld or vehicle-mounted; on water; or in the air on aircraft, balloons, and satellites.

[0079] The roles of radio access network devices and terminals can be relative. For example, the helicopter or drone 120i in Figure 1 can be configured as a mobile base station. For devices 120j accessing the radio access network 100 via 120i, 120i is a base station; however, for 110a, 120i is a terminal. That is, communication between 110a and 120i occurs via a wireless air interface protocol. Of course, communication between 110a and 120i can also occur via an interface protocol between radio access network devices. In this case, 120i is also a base station relative to 110a. Therefore, radio access network devices and terminal devices can be collectively referred to as communication devices. Devices 110a, 110b, and 120a-120j in Figure 1 can be referred to as communication devices having their respective functions, such as base station functions or terminal functions.

[0080] It should be understood that FIG1 is only a schematic diagram, and the communication system may further include other devices, such as wireless relay devices and wireless backhaul devices, which are not shown in FIG1 .

[0081] The following, in conjunction with Figure 2, briefly describes the physical layer processing of data to be transmitted during data communication between an access network device and a terminal device. It should be understood that the signal processing shown in Figure 2 can be performed by the access network device or the terminal device, and this application does not limit this.

[0082] As shown in FIG2 , when sending information data, the first device (for example, the access network device or terminal device shown in FIG1 ) can divide the information sequence from the upper layer (for example, the media access control (MAC) layer) into multiple transport blocks (TBs) according to the size of the transport block supported by the system, and for each transport block a0, a1, a2, a3, ..., a A-1 Add cyclic redundancy check (CRC) check bits p0, p1, p2, p3, ..., p L-1 Get the sequence b0,b1,b2,b3,…,b B-1 (i.e., A+L=B, where A is the bit length of transport block a0, L is the length of P0, and B is the bit length of sequence b0), where the obtained sequences b0, b1, b2, b3, ..., b B-1 , which can be called TB to be transmitted.

[0083] It should be understood that for each transmission block a0, a1, a2, a3, ..., a A-1 The process of adding a CRC check of the same length may be an optional step. When the process of adding a CRC check for each transport block is not included, the transport blocks a0, a1, a2, a3, ..., a A-1 , also known as TB to be transmitted.

[0084] If the transmission blocks b0,b1,b2,b3,…,b are added after verification B-1 If the size exceeds the preset segmentation length of the channel coding, it is necessary to divide the transmission block into several code blocks (code blocks, CB). Among them, each code block (each code block can be the information bit sequence to be transmitted in this application) may include several bits in the transmission block, and may also include CRC check bits of these bits. Afterwards, the first device may perform channel coding on each code block, for example, using low-density parity check code (LDPC) coding or polar code coding to obtain a corresponding coded code block. Each coded code block may include multiple information bits before coding in the code block and check bits generated by coding.

[0085] The first device may store the coded bit sequence in a circular buffer of the first device for rate matching. The first communication device may select a segment of coded bits from the circular buffer (the segment of coded bits may be the bit sequence to be transmitted in this application), perform modulation processing, map it into modulation symbols, and transmit a signal including the modulation symbols.

[0086] The second device demodulates the received modulated symbols and stores the soft values ​​of the received coded bits in the corresponding locations in the soft information cache. If retransmission occurs, the second device combines the soft values ​​of the coded bits for each retransmission and stores them in the soft information cache. Combining means combining the soft values ​​of the coded bits received twice if the positions of the coded bits are the same.

[0087] The second device may directly decode all soft values ​​in the soft information buffer, for example, using LDPC decoding or Polar decoding, to obtain a corresponding information sequence. The information sequence obtained by channel decoding may be sent to an upper layer (eg, a MAC layer).

[0088] It should be understood that the process in which the second device processes the received modulation symbols to obtain the information sequence can be regarded as the inverse process of the process in which the first device processes the information data to be sent to obtain the coded bit sequence.

[0089] High-order modulation can further improve spectral efficiency. In high-order modulation, because different symbols have different energies, average energy can be saved by sending more low-energy symbols and fewer high-energy symbols. Theoretical analysis shows that for a Gaussian white noise channel, the mutual information per unit energy is maximized when the transmitted symbols follow a Gaussian distribution. Compared to a uniform distribution, a Gaussian distribution theoretically offers a performance gain of approximately 1.53 decibels.

[0090] To improve transmission performance, there are currently two implementation methods:

[0091] Method 1: Geometric shaping: maintains the equal probability distribution of input symbols, but makes special designs for the constellation points, with low-energy constellation points distributed more densely and high-energy constellation points distributed more sparsely.

[0092] Method 2: Probabilistic shaping: Keep the constellation distribution unchanged and adjust the probability of the constellation points. The probability of low-energy symbols is higher, and the probability of high-energy symbols is lower.

[0093] Both approaches have their own advantages and disadvantages. Probabilistic shaping typically requires a complex distribution matcher, significantly altering the coded modulation process, but offering greater performance gains. Geometric shaping, on the other hand, requires less modification to the coding process and can achieve certain gains at the cost of less implementation complexity.

[0094] Currently, existing standards specify QAM modulation schemes such as 4QAM, 16QAM, 256QAM, and so on, up to 1024QAM. 4QAM can be viewed as a complex symbol (-1+1i, -1-1i, 1+1i, 1-1i), whose real and imaginary parts are binary phase shift keying (BPSK) modulation. 16QAM's real symbol is (-3-3i, -3-1i, -3+1i, -3+3i, -1-3i, -1-1i, -1+1i, -1+3i, 1-3i, 1-1i, 1+1i, 1+3i, 3-3i, 3-1i, 3+1i, 3+3i), whose real and imaginary parts are amplitude shift keying (ASK) modulation. As shown in FIG2 , when the QAM modulation scheme provided in the current standard is used for modulation, the constellation points of the low-order modulation are a subset of the constellation points of the high-order modulation. For example, the constellation points of 64QAM are a subset of the constellation points of 256QAM.

[0095] As can be seen from Figure 3, the multiple constellation points corresponding to QAM modulation modes of different orders in the constellation diagram are evenly distributed. In other words, if every two adjacent constellation points in any row or column of the multiple constellation points corresponding to the same order of QAM are regarded as a group of adjacent constellation points, the distance between the constellation points of any two groups of adjacent constellation points in the multiple constellation points is the same.

[0096] To achieve geometric shaping gain, related technologies propose using amplitude phase shift keying (APSK) as a basic framework to optimize the distribution of constellation points. As shown in Figure 4, the constellation points in this scheme are irregular, and the real and imaginary parts are not independent, resulting in high demodulation complexity.

[0097] In light of this, the present application proposes a communication method and related apparatus. In this method, constellation points are non-uniformly extracted from the set of constellation points corresponding to the QAM modulation scheme defined in existing standards to form a low-order QAM modulation scheme for modulating the bit sequence to be transmitted. This scheme achieves shaping gain while maintaining the independence of the real and imaginary parts, resulting in low demodulation complexity.

[0098] To facilitate understanding of the embodiments of the present application, the following points are first explained:

[0099] First, in the embodiments of this application, prefixes such as "first" and "second" are used solely to distinguish between different items belonging to the same category and do not constrain the order, size, or quantity of the items. For example, "first modulation scheme" and "second modulation scheme" are simply different modulation schemes; there is no temporal or priority relationship between the two.

[0100] Second, the "sending" and "receiving" in the embodiments of the present application indicate the direction of signal transmission. For example, "sending indication information" can be understood as the destination end of the information is the terminal device, which can include direct sending through the air interface, and also include indirect sending through the air interface by other units or modules. "Receiving indication information" can be understood as the source end of the configuration information is the network device, which can include direct reception from the network device through the air interface, and also include indirect reception from the network device through the air interface from other units or modules. "Sending" can also be understood as the "output" of the chip interface, and "receiving" can also be understood as the "input" of the chip interface.

[0101] In other words, sending and receiving can be carried out between devices, for example, between a terminal device and a network device; or it can be carried out within a device, for example, sending or receiving between components, modules, chips, software modules or hardware modules within the device through a bus, wiring or interface.

[0102] It is understood that before information is sent from the source to the destination, it may undergo necessary processing, such as encoding and modulation. After receiving the information from the source, the destination may also perform corresponding processing, such as decoding and demodulation, to interpret the valid information from the source. Similar expressions in this application can be understood similarly and will not be repeated here.

[0103] Third, in the embodiments of the present application, "at least one" refers to one or more, and "more" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship, but does not exclude the situation where the previous and next associated objects are in an "and" relationship. The specific meaning can be understood in conjunction with the context. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c; a and b; a and c; b and c; or a and b and c. Where a, b, c can be single or multiple.

[0104] Fourth, in the embodiment of the present application, "indication" may include direct indication and indirect indication, and may also include explicit indication and implicit indication. The information indicated by a certain information (such as the first information described below) is called information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated, such as but not limited to, directly indicating the information to be indicated, such as the information to be indicated itself or the index of the information to be indicated. The information to be indicated may also be indirectly indicated by indicating other information, wherein the other information has an association relationship with the information to be indicated; or only a part of the information to be indicated may be indicated, while the other parts of the information to be indicated are known or agreed in advance. For example, the indication of specific information may be achieved by means of the arrangement order of each information agreed in advance (such as predefined by the protocol), thereby reducing the indication overhead to a certain extent. The present application does not limit the specific method of indication.

[0105] It can be understood that, for the sender of the indication information, the indication information can be used to indicate the information to be indicated, and for the receiver of the indication information, the indication information can be used to determine the information to be indicated.

[0106] Fifth, in the embodiments of the present application, descriptions such as "when...", "in the case of...", "if" and "if" all mean that the device (such as a network device or a terminal device) will make corresponding processing under certain objective circumstances. It does not limit the time, and does not require the device (such as a network device or a terminal device) to have a judgment action when implementing it, nor does it mean that there are other limitations.

[0107] Sixth, the storage involved in this application may refer to storage in one or more memories. The one or more memories may be provided separately or integrated into an encoder or decoder, a processor, or a communication device. The one or more memories may also be provided in part separately and in part integrated into a decoder, a processor, or a communication device. The type of memory may be any form of storage medium, and this application is not limited thereto.

[0108] The method provided in the embodiment of the present application is described in detail below in conjunction with Figures 5 and 6. The method can be applied to the communication system shown in Figure 1, but the embodiment of the present application is not limited thereto.

[0109] In the flowchart shown in FIG5 , the method is illustrated from the perspective of interaction between communication devices, but the present application does not limit the execution subject of the method. For example, the first device in FIG5 can be a network device or a terminal device, or a chip, chip system, or processor that can support the first device to implement the method, or a logic module or software that can implement all or part of the functions of the first device; the second device in FIG5 can be a network device or a terminal device, or a chip, chip system, or processor that can support the second device to implement the method, or a logic module or software that can implement all or part of the functions of the second device.

[0110] FIG5 is a schematic flow chart of a communication method 500 provided in an embodiment of the present application. As shown in FIG5 , the method 500 may include steps S501 to S504. Each step shown in FIG5 is described in detail below.

[0111] S501: A first device obtains a bit sequence to be transmitted.

[0112] In the present application, the bit sequence to be transmitted may be a sequence obtained after the information to be transmitted undergoes channel coding and rate matching. The process of obtaining the bit sequence can be referred to the above description and will not be repeated here.

[0113] S502: The first device modulates a bit sequence based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol.

[0114] The plurality of constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to the first constellation point set corresponding to the first modulation scheme; the first constellation point set is a subset of the second constellation point set, and the second constellation point set is a set of plurality of constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme. However, it should be noted that the third constellation point set may not be a subset of the second constellation point set.

[0115] The uneven distribution of the multiple constellation points in the third constellation point set can be understood as follows: every two adjacent constellation points in any coordinate direction in the third constellation point set are considered as a group of adjacent constellation points, and at least two groups of adjacent constellation points in the third constellation point set have different inter-constellation point distances. For example, among the multiple constellation points in the third constellation point set, low-energy constellation points are distributed more densely, while high-energy constellation points are distributed more sparsely.

[0116] The similarity between the third constellation point set and the first constellation point set can be understood as follows: the number of constellation points included in the third constellation point set is the same as the number of constellation points included in the first constellation point set; the number of constellation points located in the same coordinate direction in the third constellation point set and the first constellation point set is the same; if every two adjacent constellation points located in the same constellation point set in the same coordinate direction are regarded as a group of adjacent constellation points, and the ratio of the distance between the group of adjacent constellation points located at the first position in the first constellation point set to the distance between the group of adjacent constellation points located at the first position in the third constellation point set is the same as the ratio of the distance between the group of adjacent constellation points located at the second position in the first constellation point set to the distance between the group of adjacent constellation points located at the second position in the third constellation point set.

[0117] Optionally, the third constellation point set may be the same as the first constellation point set.

[0118] It should be understood that the plurality of constellation points in the second constellation point set corresponding to the predefined second modulation scheme may be uniformly distributed. For a description of uniform distribution, reference may be made to the above description in conjunction with FIG3 , which will not be repeated here.

[0119] For example, the second modulation scheme may be a QAM modulation scheme defined in an existing standard, such as 1024QAM defined in an existing standard or other higher-order QAM modulation schemes. If the second modulation scheme is the predefined 1024QAM, the second constellation point set includes 1024 uniformly distributed constellation points.

[0120] Since the order of the second modulation scheme is higher than that of the first modulation scheme, the order of the first modulation scheme should be less than 1024. For example, the first modulation scheme can be 4QAM, 16QAM, 64QAM, or 256QAM. If the first modulation scheme is 4QAM, the first constellation point set can be 4 constellation points extracted from the second constellation point set in an uneven manner; if the first modulation scheme is 16QAM, the first constellation point set can be 16 constellation points extracted from the second constellation point set in an uneven manner; if the first modulation scheme is 64QAM, the first constellation point set can be 64 constellation points extracted from the second constellation point set in an uneven manner; if the first modulation scheme is 256QAM, the first constellation point set can be 256 constellation points extracted from the second constellation point set in an uneven manner.

[0121] Exemplarily, the first device modulating the bit sequence based on the first modulation scheme may include: the first device modulating the bit sequence based on a correspondence between each constellation point in a first constellation point set corresponding to the first modulation scheme and the bit sequence. The specific modulation process can be found in the previous description and is not further described here.

[0122] S503: The first device sends a modulation symbol to the second device. Correspondingly, the second device receives the modulation symbol from the first device.

[0123] S504: Demodulate the modulated symbol to obtain a bit sequence.

[0124] It should be understood that the process of demodulating the modulation symbols is the inverse process of modulating the bit sequence. The process of how to demodulate the modulation symbols can be referred to the previous description and will not be repeated here.

[0125] In the embodiments of the present application, since the multiple constellation points in the third constellation point set are non-uniformly distributed and similar to the first constellation point set, and the first constellation point set is a subset of the second constellation point set, the bit sequence to be transmitted is modulated by the third modulation scheme and mapped to the constellation points in the third constellation point set. This is equivalent to performing geometric shaping, thereby achieving shaping gain. Furthermore, since the first constellation point set is a subset of the predefined second constellation point set, this scheme only requires defining a single constellation point extraction method to obtain the first constellation point set from the predefined constellation point set, resulting in low implementation complexity. Optionally, the position of each constellation point in the constellation point set corresponding to the first modulation scheme can be determined by the first mapping relationship.

[0126] The first mapping relationship indicates multiple modulation schemes and positions of constellation points corresponding to each modulation scheme, where the multiple modulation schemes include the first modulation scheme.

[0127] It should be understood that the multiple modulation schemes may include multiple modulation schemes with the same modulation order, or may include multiple modulation schemes with different modulation orders. For example, the modulation order of 16QAM is 4, and the modulation order of 4 can correspond to multiple modulation schemes, and the positions of the constellation points corresponding to different modulation schemes are different. For another example, the modulation order of 16QAM is 4, and the modulation order of 64QAM is 8. The modulation order of 4 and the modulation order of 8 can correspond to at least two modulation schemes, and the positions of the constellation points corresponding to the two modulation schemes are different. In particular, the multiple constellation points included in each constellation point set corresponding to 16QAM and 64QAM are non-uniformly distributed, and the multiple constellation point sets can all be subsets of the constellation point set corresponding to a predefined QAM modulation scheme with a modulation order greater than 8 (for example, 1024QAM).

[0128] Exemplarily, the first mapping relationship includes a correspondence between multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point.

[0129] Since the first mapping relationship includes a correspondence between multiple modulation schemes and multiple position coordinate sets, the first device can determine a position coordinate set corresponding to the first modulation scheme from multiple position coordinate sets based on the first modulation scheme and the first mapping relationship, and the multiple constellation points identified by the position coordinate set are the constellation points in the first constellation point set.

[0130] Exemplarily, each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

[0131] The present application sequentially numbers the multiple constellation points in the second constellation point set, such that each constellation point corresponds to a sequence number, and different constellation points correspond to different sequence numbers. Because the first constellation point set corresponding to the first modulation scheme is a subset of the second constellation point set corresponding to the second modulation scheme, each constellation point in the first constellation point set can be identified by the sequence number corresponding to the constellation point.

[0132] Due to the correspondence between multiple modulation schemes and multiple sequence number sets in the first mapping relationship, the first device can determine a sequence number set corresponding to the first modulation scheme from multiple sequence number sets based on the first modulation scheme and the first mapping relationship, and the constellation point identified by each sequence number in the sequence number set belongs to the first constellation point set.

[0133] Table 1

[0134] Table 1 shows a first mapping relationship. As shown in Table 1, the constellation point sets corresponding to modulation orders 2 to 8 are all subsets of the constellation point set corresponding to modulation order 10. Among them, modulation order 2 is the modulation order corresponding to 4QAM, modulation order 8 is the modulation order corresponding to 256QAM, and modulation order 10 is the modulation order corresponding to 1024QAM. Each MCS index can be regarded as a modulation scheme in this application, and each MCS index corresponds to a constellation point position set (i.e., a constellation point position column).

[0135] In addition, the above Table 1 also includes the target code rate and spectrum efficiency corresponding to each modulation scheme.

[0136] Each set of values ​​shown in the constellation point set column in Table 1 can be used to determine the positions of multiple constellation points. Specifically, each set of values ​​includes multiple values. The real part value of the constellation point corresponding to each set of values ​​can be obtained by traversing each value in the multiple values. The imaginary part value of the constellation point corresponding to each set of values ​​can be obtained by traversing each value in the multiple values. By combining different real part values ​​with different imaginary part values, the positions of the multiple constellation points corresponding to each set of values ​​can be obtained. For example, if the set of values ​​is [abcd], there are four possible real part values: a, b, c, d, and four possible imaginary part values: ai, bi, ci, and di. Combining different real part values ​​with different imaginary part values ​​yields a total of 16 combinations: (a-ai)(a+bi)(a+ci)(a+di), (b+ai)(b+bi)(b+ci)(b+di), (c+ai)(c+bi)(c+ci)(c+di), and (d+ai)(d+bi)(d+ci)(d+di).

[0137] For example, the four constellation points corresponding to the constellation point set [1 -1] in Table 1 are: (-1+i)(-1-i), (1+i)(1-i); the 16 constellation points corresponding to the positions of the constellation points in Table 1 are [-21 -10 10 21] are: (-21-21i)(-21-10i)(-21+10i)(-21+21i), (-10-21i)(-10-10i)(-10+10i)(-10+21i), (10-21i)(10-10i)(10+10i)(10+21i), (21-21i)(21-10i)(21+10i)(21+21i); the positions of the constellation points in Table 1 are [-21 -13 -7 -3 3 7 13 The 64 constellation points corresponding to 21] are: (-21-21i)(-21-13i)(-21-7i)(-21-31i)(-10+3i)(-10+7i)(-10+13i)(-10+21i), (-13-21i)(-13-13i)(-13-7i)(-13-3i)(-13+3i)(-13+7i)(-13+13i)(-13+21i), (-7-21i)(-7-13i)(-7-7i)(-7-3i)(-7+3i)(-7+7i)(-7+13i)(-7+21i), (-3-21i)(-3-13i)(-3-7i)(-3-3i)(-3+3i )(-3+7i)(-3+13i)(-3+21i);(3-3i)(3-13i)(3-7i)(3-3i)(3+3i)(3+7i)(3+13i)(3+21i), (7-21i)(7-13i)(7-7i)(7-3i)(7+3i)(7+7i)(7+13i)(7+21i), (13-21i)(13-13i)(13-7i)(13-3i)(13+3i)(13+7i)(13+13i)(13+21i), (21-21i)(21-13i)(21-7i)(21-3i)(21+3i)(21+7i)(21+13i)(21+21i). And so on, the constellation points corresponding to the positions of other constellation points in Table 1 are not listed here one by one.

[0138] It should be understood that the correspondence shown in Table 1 above can be called an MCS table.

[0139] Optionally, among the multiple modulation schemes, multiple constellation points in the constellation point set corresponding to each modulation scheme are symmetric about the origin.

[0140] For example, when constellation points are identified by serial numbers, the multiple serial numbers used to identify constellation points in each constellation point set may be symmetrical about 15.5 or symmetrical about other numerical values, which is not limited in this application.

[0141] The constellation points corresponding to the first modulation scheme described in method 500 above are determined based on geometric shaping. The correspondence shown in Table 1, compared to the MCS table in the current 3GPP technical specification, adds a constellation point set corresponding to each MCS index. The constellation point set corresponding to each MCS index represents the position mapped to the constellation diagram, and therefore this column is also referred to as a mapping column.

[0142] Table 1 can be considered an MCS table designed for geometric shaping. However, in actual communication systems, there may also be MCS tables adapted for probabilistic shaping techniques. MCS tables determined by communication devices based on these two methods can achieve shaping gain when modulating bit sequences based on predefined MCS tables. Therefore, how communication devices select an MCS table when modulating bit sequences is a pressing issue. The following describes this selection process with reference to Figure 6.

[0143] The flowchart shown in FIG6 illustrates the method from the perspective of interaction between communication devices, but the present application does not limit the execution subject of the method. For example, the first device in FIG6 can be a terminal device, or a chip, chip system, or processor that supports the first device to implement the method, or a logic module or software that can implement all or part of the functions of the first device; the second device in FIG6 can be a network device, or a chip, chip system, or processor that supports the second device to implement the method, or a logic module or software that can implement all or part of the functions of the second device.

[0144] FIG6 is a schematic flow chart of another communication method 600 provided in an embodiment of the present application. As shown in FIG6 , the method 600 may include steps S601 to S603. Each step shown in FIG6 is described in detail below.

[0145] S601: The second device generates indication information.

[0146] The indication information may be used to indicate the use of parameters in the first MCS table or the second MCS table for encoding and modulation. The first MCS table is designed for geometric shaping or probability shaping, and the second MCS table is predefined.

[0147] Since the first MCS table in the present application is designed for geometric shaping or probabilistic shaping, when the shaping technology is adopted, the transmission performance of the first MCS table is better than the transmission performance of the second MCS table.

[0148] Exemplarily, the content indicated by the first indication information is related to whether shaping technology is adopted. When the first indication information indicates shaping, it means that the parameters in the first MCS table are used for encoding and modulation; otherwise, the parameters in the second MCS table are used for encoding and modulation.

[0149] It should be understood that the above-mentioned first information can be carried in physical layer signaling, for example, downlink control information (DCI).

[0150] S602: The second device sends indication information to the first device. Correspondingly, the first device receives the indication information from the second device.

[0151] S603: The first device determines, based on the indication information, to use the first MCS table or the second MCS table to modulate the information bit sequence to be transmitted.

[0152] For the description of the information bit sequence, please refer to the relevant description in the information encoding process shown in Figure 2 above, and will not be repeated here.

[0153] Exemplarily, if the indication information indicates that parameters in a first MCS table are used for encoding and modulation, the second device determines, based on the indication information, to use the parameters in the first MCS table to encode and modulate the information bit sequence to be transmitted. Alternatively, if the indication information indicates that parameters in a second MCS table are used for encoding and modulation, the second device determines, based on the indication information, to use the parameters in the second MCS table to encode and modulate the information bit sequence to be transmitted.

[0154] Optionally, after S603, the method 600 further includes: the second device encoding and modulating the information bit sequence using parameters in the first MCS table or the second MCS table to obtain a modulation symbol; and sending the modulation symbol to the first device. Correspondingly, the first device receives the modulation symbol, demodulates and decodes the modulation symbol to obtain the information bit sequence.

[0155] It should be understood that the above demodulation is the inverse process of modulation. The detailed process of modulation and demodulation will not be repeated here.

[0156] Exemplarily, the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table may be different. In other words, the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table may be different.

[0157] Exemplarily, when the modulation orders corresponding to the same index are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table. When the modulation orders corresponding to the same spectral efficiency are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0158] It should be noted that, compared with the second MCS table, the first MCS table has a situation where the lower the spectrum efficiency, the higher the corresponding modulation order.

[0159] The following describes the differences and connections between the first MCS table and the second MCS table in conjunction with Table 1 and Table 2.

[0160] Table 2

[0161] Table 3

[0162] Table 2 shows a second MCS table, and Table 3 shows a first MCS table. As shown in Tables 2 and 3, the MCS indexes included in Table 2 are the same as those in Table 3. However, in the second MCS table shown in Table 2, the switching point for switching the modulation order from 2 to 4 is MCS index 10, and the switching point for switching from 4 to 6 is MCS index 17. In contrast, in the first MCS table shown in Table 3, the switching point for switching from 2 to 4 is MCS index 8, and the switching point for switching from 4 to 6 is MCS index 14. This shows that the modulation order switching points in the first MCS table are earlier than those in the second MCS table.

[0163] The modulation order switching points in the first MCS table are earlier than those in the second MCS table. This can also be understood as follows: In the second MCS table shown in Table 2, the switching point from modulation order 2 to 4 is at a spectral efficiency of 1.3281, and the switching point from modulation order 4 to 6 is at a spectral efficiency of 2.5664. In contrast, in the first MCS table shown in Table 3, the switching point from modulation order 2 to 4 is at a spectral efficiency of 1.1758, and the switching point from modulation order 4 to 6 is at a spectral efficiency of 2.1621. This shows that the modulation order switching points in the first MCS table are earlier than those in the second MCS table.

[0164] It should be noted that the embodiments of method 500 and method 600 described above can be combined with each other or implemented independently. When the embodiments of method 500 and method 600 are combined, the communication method provided in this application may include: a first device instructing a second device to modulate a bit sequence to be transmitted using a first modulation scheme in a first MCS table, and the second device may modulate the transmitted bit sequence according to the first modulation scheme indicated by the first device. The detailed process of combining the embodiments of method 500 and method 600 can be referred to the above description of the embodiments shown in Figures 5 and 6, and will not be repeated here.

[0165] It should be understood that the size of the serial numbers of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0166] Figures 7 to 10 are schematic diagrams of possible devices provided by embodiments of the present application. These devices can be used to implement the functions of the first device or the second device in the above method embodiments, and thus can also achieve the beneficial effects of the above method embodiments.

[0167] FIG7 is a schematic block diagram of a communication device according to an embodiment of the present application. As shown in FIG7 , a communication device (hereinafter referred to as the device) 700 includes a processing module 710 and a transceiver module 720 .

[0168] In one possible design, the apparatus 700 is used to implement the functions of the first device in the method embodiments shown in Figures 5 and 6. For example, the apparatus 700 may correspond to the terminal device in Figure 1.

[0169] Example 1: The processing module 710 is used to: obtain a bit sequence to be transmitted; and modulate the bit sequence based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol; the multiple constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to the first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of the second constellation point set, the second constellation point set is a set of multiple constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme; the transceiver module 720 is used to: send the modulation symbol.

[0170] Optionally, the third constellation point set is the same as the first constellation point set.

[0171] Optionally, the position of each constellation point in the constellation point set corresponding to the first modulation scheme is determined by a first mapping relationship, and the first mapping relationship indicates multiple modulation schemes and the position of the constellation point corresponding to each modulation scheme, and the multiple modulation schemes include the first modulation scheme.

[0172] Optionally, the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point.

[0173] Optionally, each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

[0174] Optionally, among the multiple modulation schemes, multiple constellation points in the constellation point set corresponding to each modulation scheme are symmetric about the origin.

[0175] Optionally, the second modulation scheme is 1024QAM.

[0176] A more detailed description of the processing module 710 and the transceiver module 720 can be directly obtained by referring to the relevant description in the embodiment shown in FIG5 , and will not be repeated here.

[0177] In Example 2, the transceiver module 720 is used to: receive indication information, where the indication information is used to indicate the use of parameters in the first MCS table or the second MCS table for encoding and modulation, where the first MCS table is designed for geometric shaping or probabilistic shaping, and the second MCS table is predefined; the processing module 710 is used to: determine, based on the indication information, whether to use the first MCS table or the second MCS table for encoding and modulating the information bit sequence to be transmitted.

[0178] Optionally, there are different modulation orders in the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0179] Optionally, there are different modulation orders in the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0180] Optionally, the processing module 710 is further used to: use the parameters in the first MCS table or the second MCS table to modulate and decode the information bit sequence to obtain modulation symbols; and the transceiver module 720 is further used to: send the modulation symbols.

[0181] A more detailed description of the transceiver module 720 and the processing module 710 can be directly obtained by referring to the relevant description in the embodiment shown in FIG6 , and will not be repeated here.

[0182] Another possible design is that the apparatus 700 is used to implement the functions of the second device in the method embodiments shown in Figures 5 and 6. For example, the apparatus 700 may correspond to the access network device in Figure 1.

[0183] Example 1: The transceiver module 720 is used to: receive modulation symbols, where the modulation symbols are obtained by mapping the bit sequence to be transmitted to each constellation point in the first constellation point set based on the first modulation scheme; the multiple constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to the first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of the second constellation point set, the second constellation point set is a set of multiple constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme; the processing module 710 is used to: demodulate the modulation symbols to obtain the bit sequence.

[0184] Optionally, the third constellation point set is the same as the first constellation point set.

[0185] Optionally, the position of each constellation point in the constellation point set corresponding to the first modulation scheme is determined by a first mapping relationship, and the first mapping relationship indicates multiple modulation schemes and the position of the constellation point corresponding to each modulation scheme, and the multiple modulation schemes include the first modulation scheme.

[0186] Optionally, the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point.

[0187] Optionally, each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

[0188] Optionally, among the multiple modulation schemes, multiple constellation points in the constellation point set corresponding to each modulation scheme are symmetric about the origin.

[0189] Optionally, the second modulation scheme is 1024QAM.

[0190] A more detailed description of the transceiver module 720 and the processing module 710 can be directly obtained by referring to the relevant description in the embodiment shown in FIG5 , and will not be repeated here.

[0191] Example 2: The processing module 710 is used to: generate indication information, where the indication information is used to indicate the use of parameters in the first MCS table or the second MCS table for encoding and modulation, where the first MCS table is designed for geometric shaping or probabilistic shaping, and the second MCS table is predefined; the transceiver module 720 is used to: send the indication information.

[0192] Optionally, there are different modulation orders in the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0193] Optionally, there are different modulation orders in the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

[0194] Optionally, the transceiver module 720 is used to: receive modulation symbols, where the modulation symbols are obtained by encoding and modulating the information bit sequence to be transmitted using the parameters in the first MCS table or the second MCS table; the processing module 710 is used to: demodulate and decode the modulated symbols to obtain the information bit sequence.

[0195] A more detailed description of the processing module 710 and the transceiver module 720 can be directly obtained by referring to the relevant description in the embodiment shown in FIG6 , and will not be repeated here.

[0196] It should be noted that the apparatus 700 may include a sending module but not a receiving module. Alternatively, the apparatus 700 may include a receiving module but not a sending module. This may depend on whether the above solution executed by the apparatus 700 includes both a sending action and a receiving action.

[0197] FIG8 is another schematic block diagram of a communication device provided in an embodiment of the present application. As shown in FIG8 , a communication device (hereinafter referred to as a device) 800 includes one or more processors 810. The processor 810 may be a general-purpose processor or a dedicated processor. For example, it may be a baseband processor or a central processing unit. The baseband processor may be used to process communication protocols and communication data, and the central processing unit may be used to control the device (e.g., the first device, the second device, or the chip), execute software programs, and process data of the software programs.

[0198] Optionally, in one design, the processor 810 may include a program (also referred to as code or instructions), which may be executed on the processor 810 to cause the apparatus 800 to perform the method performed by the first device or the second device in the above method embodiment. In another possible design, the apparatus 800 includes a circuit (not shown in FIG8 ) configured to implement the functions of the first device or the second device in the above method embodiment.

[0199] Exemplarily, the processor 810 may be configured to execute a computer program or instruction in the memory to implement the steps performed by the first device or the second device in the method embodiment shown in any one of the embodiments shown in FIG. 5 and FIG. 6 .

[0200] Optionally, the device 800 may include one or more memories 820 on which programs (sometimes also referred to as codes or instructions) are stored. The programs can be run on the processor 810 so that the device 800 executes the method executed by the first device or the second device in the above embodiment.

[0201] Optionally, the processor 810 and / or the memory 820 may include an artificial intelligence (AI) module, which is used to implement AI-related functions. The AI ​​module may be implemented through software, hardware, or a combination of software and hardware. For example, the AI ​​module may include a wireless intelligent controller (RIC) module. For example, the AI ​​module may be a near real-time RIC or a non-real-time RIC.

[0202] Optionally, data may be stored in the processor 810 and / or the memory 820. The processor and memory may be provided separately or integrated together.

[0203] Optionally, the apparatus 800 may further include a communication interface 830. The processor 810 may also be sometimes referred to as a processing unit, which controls the apparatus (e.g., the first device or the second device). The communication interface 830 may also be sometimes referred to as a transceiver unit, a transceiver, a transceiver circuit, or a transceiver, etc., which is used to implement the transceiver function of the apparatus.

[0204] Optionally, the apparatus 800 further includes a communication interface 830. The processor 810 and the communication interface 830 are coupled to each other. It is understood that the communication interface 830 may be a transceiver or an input / output interface.

[0205] When the apparatus 800 is used to implement the method shown in FIG5 or FIG6, the processor 810 is used to perform the functions of the processing module, and the communication interface 830 is used to perform the functions of the sending module or the receiving module. Whether the communication interface 830 is used for sending or receiving can be determined by whether it is used for performing the sending action or the receiving action in the solution implemented by the apparatus 800.

[0206] When the apparatus 800 is a chip implemented in a first device, the chip implements the functions of the first device in the above method embodiment. The chip of the first device receives a signal from another module (such as a radio frequency module or antenna) in the first device, and the signal may be sent from the second device to the first device; or the chip of the first device sends a signal to another module (such as a radio frequency module or antenna) in the first device, and the signal may be sent from the first device to the second device.

[0207] When the apparatus 800 is a chip implemented in a second device, the chip implements the functions of the second device in the method embodiment described above. The chip of the second device receives a signal from another module (such as a radio frequency module or antenna) in the second device, which may be a signal sent from the first device to the second device; or the chip of the second device sends a signal to another module (such as a radio frequency module or antenna) in the second device, which may be a signal sent from the second device to the first device.

[0208] It is understood that when the apparatus 800 is a first device or a second device, the communication interface 830 may be a transceiver, specifically including a transmitter and a receiver, where the transmitter is used to transmit signals and the receiver is used to receive signals. When the apparatus 800 is a chip used in the first device or the second device, the communication interface 830 may be an input / output circuit, where the input circuit can be used for receiving and the output interface can be used for transmitting.

[0209] It should be noted that the above method embodiments can be applied to or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiments can be completed by hardware integrated logic circuits in the processor or by software instructions.

[0210] The processor may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0211] The steps of the method disclosed in the embodiments of this application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and, in conjunction with its hardware, completes the steps of the above method.

[0212] The present application also provides a computer-readable medium having a computer program stored thereon, which implements the functions of the above-mentioned method embodiment when executed by a computer.

[0213] The present application also provides a computer program product comprising instructions, which implements the functions of the above method embodiments when executed by a computer.

[0214] The memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be 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), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0215] The methods provided in the above embodiments can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, they can be implemented in whole or in part in the form of a computer program product. The computer program product may include one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic disk), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state disk (SSD)).

[0216] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0217] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0218] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0219] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0220] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0221] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to some embodiments or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0222] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: include: Obtaining a bit sequence to be transmitted; The bit sequence is modulated based on a third modulation scheme to map the bit sequence to each constellation point in a third constellation point set to obtain a modulation symbol; the plurality of constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to a first constellation point set corresponding to the first modulation scheme, the first constellation point set is a subset of a second constellation point set, the second constellation point set is a set of a plurality of constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme; The modulation symbols are transmitted.

2. The method according to claim 1, characterized in that The third constellation point set is the same as the first constellation point set.

3. The method according to claim 1 or 2, characterized in that The position of each constellation point in the constellation point set corresponding to the first modulation scheme is determined by a first mapping relationship, and the first mapping relationship indicates multiple modulation schemes and the position of the constellation point corresponding to each modulation scheme, and the multiple modulation schemes include the first modulation scheme.

4. The method according to claim 3, characterized in that The first mapping relationship includes a correspondence between the multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point.

5. The method according to claim 3, characterized in that Each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

6. The method according to any one of claims 3 to 5, characterized in that Among the multiple modulation schemes, multiple constellation points in a constellation point set corresponding to each modulation scheme are symmetric about the origin.

7. The method according to any one of claims 1 to 6, characterized in that The third modulation scheme is 1024 Quadrature Amplitude Modulation QAM.

8. A communication method, characterized in that: include: receiving a modulation symbol, where the modulation symbol is obtained by mapping a bit sequence to each constellation point in a third constellation point set based on a third modulation scheme; The plurality of constellation points in the third constellation point set are unevenly distributed, and the third constellation point set is similar to a first constellation point set corresponding to a first modulation scheme, the first constellation point set is a subset of a second constellation point set, the second constellation point set is a set of a plurality of constellation points corresponding to a predefined second modulation scheme, the order of the second modulation scheme is higher than the order of the first modulation scheme, and the order of the third modulation scheme is the same as the order of the first modulation scheme; The modulation symbol is demodulated to obtain the bit sequence.

9. The method according to claim 8, characterized in that The third constellation point set is the same as the first constellation point set.

10. The method according to claim 8 or 9, characterized in that The position of each constellation point in the constellation point set corresponding to the first modulation scheme is determined by a first mapping relationship, and the first mapping relationship indicates multiple modulation schemes and the position of the constellation point corresponding to each modulation scheme, and the multiple modulation schemes include the first modulation scheme.

11. The method according to claim 10, characterized in that The first mapping relationship includes a correspondence between the multiple modulation schemes and multiple position coordinate sets, each position coordinate set includes multiple position coordinates, and each position coordinate is used to identify the position of a constellation point in the constellation diagram.

12. The method according to claim 10, characterized in that Each constellation point in the second constellation point set corresponds to a sequence number, and each sequence number is used to identify a constellation point in the second constellation point set; the first mapping relationship includes a correspondence between the multiple modulation schemes and multiple sequence number sets, and each sequence number set includes multiple sequence numbers.

13. The method according to any one of claims 10 to 12, characterized in that Among the multiple modulation schemes, multiple constellation points in a constellation point set corresponding to each modulation scheme are symmetric about the origin.

14. The method according to any one of claims 9 to 13, characterized in that The second modulation scheme is 1024 Quadrature Amplitude Modulation QAM.

15. A communication method, characterized in that: include: receiving indication information, the indication information being used to indicate that encoding and modulation are performed using parameters in a first modulation and coding scheme MCS table or a second MCS table, wherein the first MCS table is designed for geometric shaping or probability shaping, and the second MSC table is predefined; Based on the indication information, it is determined to use the first MCS table or the second MCS table to encode and modulate the information bit sequence to be transmitted.

16. The method according to claim 15, characterized in that The content indicated by the indication information is related to whether the forming technology is adopted.

17. The method according to claim 15 or 16, characterized in that There are different modulation orders in the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

18. The method according to claim 15 or 16, characterized in that There are different modulation orders in the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

19. The method according to any one of claims 15 to 18, characterized in that The method further comprises: Modulating the bit sequence using parameters in the first MCS table or the second MCS table to obtain modulation symbols; The modulation symbols are transmitted.

20. A communication method, characterized in that: include: Generate indication information, where the indication information is used to indicate that modulation is performed using parameters in a first modulation and coding scheme MCS table or a second MCS table, where the first MCS table is determined based on geometric shaping or probability shaping, and the second MCS table is predefined; The instruction information is sent.

21. The method of claim 20, wherein: The content indicated by the indication information is related to whether the forming technology is adopted.

22. The method according to claim 20 or 21, characterized in that There are different modulation orders in the modulation orders corresponding to the same MCS index in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

23. The method according to claim 20 or 21, characterized in that There are different modulation orders in the modulation orders corresponding to the same spectrum efficiency in the first MCS table and the second MCS table, and when the modulation orders are different, the corresponding modulation order in the first MCS table is greater than the corresponding modulation order in the second MCS table.

24. The method according to any one of claims 20 to 23, characterized in that The method further comprises: receiving a modulation symbol, where the modulation symbol is obtained by encoding and modulating an information bit sequence to be transmitted using parameters in the first MCS table or the second MCS table; The modulated symbols are demodulated and decoded to obtain the information bit sequence.

25. A communication device, characterized in that: Comprising means for implementing the method as claimed in any one of claims 1 to 24.

26. A communication device, characterized in that: The device comprises a processor configured to cause the communication device to implement the method according to any one of claims 1 to 24 by executing a computer program and / or a logic circuit.

27. The device according to claim 26, characterized in that The system also includes a memory for storing a computer program and / or a configuration file of the logic circuit.

28. The device according to claim 26 or 27, characterized in that A communication interface is also included for inputting and / or outputting signals.

29. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 24 is performed.

30. A communication system, characterized in that: Includes a first device and a second device, wherein the first device is used to implement the method as described in any one of claims 1 to 7, and the second device is used to implement the method as described in any one of claims 8 to 14; or, the first device is used to implement the method as described in any one of claims 15 to 19, and the second device is used to implement the method as described in any one of claims 20 to 24.

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