CN115150241A

CN115150241A - Multi-carrier communication method and device

Info

Publication number: CN115150241A
Application number: CN202110348715.6A
Authority: CN
Inventors: 冯奇; 胡远洲; 黄煌; 毕晓艳
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-03-31
Filing date: 2021-03-31
Publication date: 2022-10-04
Also published as: WO2022206903A1

Abstract

The embodiment of the application provides a multi-carrier communication method and device, which are used for improving the reliability of multi-carrier communication and meeting the requirements of high reliability and low time delay. The multi-carrier communication method includes: a first communication device generates a first signal, wherein the first signal is obtained by performing first processing on N modulation symbols, each of the N modulation symbols is composed of L groups, each group includes M modulation symbols, the first processing includes performing M-dimensional Discrete Fourier Transform (DFT) on the M modulation symbols in each group to obtain a second signal, and performing inverse fourier transform (N = lxm) on the second signal; the first communication device transmits the first signal.

Description

Multi-carrier communication method and device

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a multi-carrier communication method and apparatus.

Background

Under a bit-interleaved coded modulation (BICM) transmission system, diversity gain is obtained by configuring time-frequency space resources, and high-reliability low-latency communication (URLLC) communication can be realized. Specifically, a larger bandwidth is configured to implement frequency diversity, a larger time slot is configured to implement time diversity, and a denser antenna is configured to implement space diversity.

Orthogonal Frequency Division Multiplexing (OFDM) used in the current mainstream scheme can guarantee low delay to a certain extent, but has low reliability and cannot well meet the requirements of high reliability and low delay.

Disclosure of Invention

The application provides a multi-carrier communication method and device, which are used for improving the reliability of multi-carrier communication and meeting the requirements of high reliability and low time delay.

In a first aspect, a multi-carrier communication method is provided. In the method, a first communication device generates a first signal and transmits the first signal. The first signal is obtained by performing first processing on N modulation symbols, the N modulation symbols are formed by L groups, each group includes M modulation symbols, the first processing includes performing M-dimensional Discrete Fourier Transform (DFT) on the M modulation symbols of each group to obtain a second signal, and performing inverse fourier transform (N = lxm) according to the second signal.

The first communication device, as a transmitter, performs L M-dimensional DFTs first, and then performs an inverse fourier transform. After passing through a multipath channel, intersymbol interference exists between the M symbols in the same group, and intersymbol interference does not exist between the symbols in different groups. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of the multicarrier communication is improved, and the requirements of high reliability and low time delay are met. It should be noted that the intersymbol interference existing between the M symbols of the same group can be equalized during the demodulation process of the receiver.

In one possible design, each modulation symbol is mapped on M subcarriers simultaneously. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, and the reliability of the multicarrier communication is improved.

In one possible design, the first processing further includes: before performing M-dimensional DFT on M modulation symbols of each group, performing phase rotation on the N modulation symbols. Further, the log-likelihood ratio fluctuation of different bits is made as small as possible, and the reliability of multi-carrier communication is improved.

In one possible design of the system, the system may be, the angle of the phase rotation is related to the modulation scheme and the element index M of the modulation symbol, M = 0. This makes it possible to make the log-likelihood ratio fluctuation of different bits as small as possible.

In one possible design, the modulation scheme is a Quadrature Amplitude Modulation (QAM) scheme, and the rotation angle of the modulation symbol of the mth element in the ith group satisfies the following formula:

l-1, representing the rotation angle of the modulation symbol of the mth element of the ith group, i = 0.

Or the modulation mode is a Phase Shift Keying (PSK) modulation mode, and the rotation angle of the modulation symbol of the mth element in the ith group meets the following formula:

r is the number of constellation points.

In this design, possible rotation angles are provided for different modulation schemes, so that log-likelihood ratio fluctuations for different bits are as small as possible.

In one possible design, the first signal satisfies the following equation:

wherein s (t) denotes the first signal, a _l，m Is the modulation symbol of the mth element of the lth group,

means that M-dimensional DFT is performed on the l-th group of M modulation symbols,

representing the inverse fourier transform, Δ f is the subcarrier spacing, and Δ f =1/T, T is the symbol period.

In one possible design, the t is related to one or more of the following information: symbol period T, cyclic prefix duration T _CP Zero padded suffix duration T _ZP Or cyclic suffix duration T _CS 。

In this design, if T takes on value and the cyclic prefix duration T _CP In this connection, resistance to channel multipath interference can be achieved, and the signal fluctuation of the first signal s (t) is small, and the communication reliability is higher. If the value of T is equal to the zero-padded suffix duration T _ZP In this regard, channel multipath interference immunity may be achieved and power may be saved. If the value of T is related to the cyclic suffix duration T _CS In this regard, channel multipath interference immunity may be achieved and out-of-band leakage may be reduced.

In one possible design, the t satisfies one of: -T _CP ≤t<T，T _CP Is the cyclic prefix duration; or 0. Ltoreq. T<T; or 0. Ltoreq. T<T+T _ZP ，T _ZP Padding zero with suffix duration; or-T _CP ≤t<T+T _CS ，T _CS Is the cyclic suffix duration. In this design, t may be a relative time, e.g., for a time, a time before that time may be a negative value.

Note that "≦" may be "<”，“<The content of the compound can also be less than or equal to the content of the compound. For example-T _CP ≤t<T may also be-T _CP <t<T, or-T _CP <T is less than or equal to T, or-T _CP ≤t≤T。

In a second aspect, a multi-carrier communication method is provided. In the method, a second communication device receives a sixth signal, and performs second processing on the sixth signal to obtain N demodulation symbols. The sixth signal is a received signal of the first signal after passing through a channel, the second processing includes performing Discrete Fourier Transform (DFT) demapping on a first symbol included in the sixth signal to obtain a third signal, the third signal includes N second symbols, the N second symbols are formed by L groups, each group includes M second symbols, and M second symbols in each group are equalized, where N = lxm.

The DFT demapping the sampled first symbol may be L M-dimensional DFT demapping the sampled first symbol.

The second communication device functions as a receiver and performs an inverse operation corresponding to the transmitter to recover the transmission signal. Intersymbol interference exists between the M symbols in the same group, and intersymbol interference does not exist between the symbols in different groups. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of multicarrier communication is improved, and the requirements of high reliability and low time delay are met.

In one possible design, the equalizing the M second symbols in each group includes phase-rotated equalizing the M second symbols in each group. Further, the log-likelihood ratio fluctuation of different bits is made as small as possible, and the reliability of multi-carrier communication is improved.

In a third aspect, a multi-carrier communication method is provided. In the method, a first communication device generates a fourth signal and transmits the fourth signal. The fourth signal is obtained by performing third processing on N modulation symbols, where the N modulation symbols are formed by L groups, each group includes M modulation symbols, and the third processing includes performing M L-dimensional Inverse Discrete Fourier Transforms (IDFTs) to obtain a fifth signal, and performing shaping filtering on the fifth signal, where N = lxm.

The first communication device acts as a transmitter and performs M L-dimensional IDFTs on modulation symbols in place of 1N-dimensional IDFT in OFDM. After passing through a multipath channel, intersymbol interference exists between the M symbols in the same group, and intersymbol interference does not exist between the symbols in different groups. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of the multicarrier communication is improved, and the requirements of high reliability and low time delay are met.

In one possible design, the third process may further include: performing phase rotation on the N modulation symbols before performing M L-dimensional IDFTs. Further, the log-likelihood ratio fluctuation of different bits is made as small as possible, and the reliability of multi-carrier communication is improved.

In one possible design, the angle of the phase rotation is related to the element index M of the modulation scheme and/or modulation symbol, M = 0. This makes it possible to make the log-likelihood ratio fluctuation of different bits as small as possible.

In one possible design, the modulation scheme is a quadrature amplitude modulation, QAM, scheme, and the rotation angle of the modulation symbol of the mth element of the L-th group is 0,l = 0.

and the rotation angle of the modulation symbol of the mth element of the ith group is represented, and R is the number of constellation points.

In one possible design, the fourth signal satisfies the following equation:

wherein s (t) represents the fourth signal, a _l，m Is the modulation symbol of the mth element of the lth group,

denotes L-dimensional IDFT of L modulation symbols, g (T) is shaping filter, T _S Is the sampling time interval.

In one possible design, the k and the m relate to one or more of the following information: cyclic prefix length N _CP Or cyclic suffix length N _CS 。

If k and m are equal to the cyclic prefix length N _CP In this connection, resistance to channel multipath interference can be achieved, and the fourth signal s (t) has small signal fluctuation and high communication reliability. If k and m are the length of the cyclic suffix N _CS In this regard, signal multipath interference immunity may be achieved and out-of-band leakage may be reduced.

In one possible design, the k and the m satisfy one of the following: -N _CP ≤kM+m<LM-1，N _CP Is the cyclic prefix length; or 0. Ltoreq. KM + m<LM-1; or-N _CP ≤kM+m<LM+N _CS -1，N _CS Is the cyclic suffix length.

In a fourth aspect, a multi-carrier communication method is provided. In the method, a second communication device receives a seventh signal, and performs fourth processing on the seventh signal to obtain N demodulation symbols. The seventh signal is a received signal of a fourth signal after passing through a channel, the fourth processing includes performing M L-dimensional discrete fourier transform DFT demapping on a third symbol included in the seventh signal to obtain an eighth signal, the eighth signal includes N fourth symbols, the N fourth symbols are formed by L groups, each group includes M fourth symbols, and M fourth symbols in each group are equalized, where N = lxm.

The second communication device acts as a receiver and performs an inverse operation corresponding to the transmitter to recover the transmission signal. Intersymbol interference exists between the M symbols in the same group, and intersymbol interference does not exist between the symbols in different groups. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of the multicarrier communication is improved, and the requirements of high reliability and low time delay are met.

In one possible design, the equalizing the M fourth symbols in each group includes: the M fourth symbols in each group are equalized for phase rotation. Further, the log-likelihood ratio fluctuation of different bits is made as small as possible, and the reliability of multi-carrier communication is improved.

In a fifth aspect, a signal is provided, the signal satisfying the following equation:

the implementation of generating the signal is not limited herein.

It should be noted that other formulas modified from the above formulas are not excluded.

In a sixth aspect, a signal is provided that satisfies the following equation:

the implementation of generating the signal is not limited herein.

In a seventh aspect, a communication device is provided for implementing the above various methods. The communication device may be the first communication device in the first aspect or the third aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; alternatively, the communication device may be the second communication device in the second or fourth aspect, or a device including the second communication device, or a device included in the second communication device. The communication device includes corresponding modules, units, or means (means) for implementing the above methods, and the modules, units, or means may be implemented by hardware, software, or by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

In an eighth aspect, a communication apparatus is provided, including: a processor and interface circuitry for communicating with a module external to the communication device; the processor is configured to execute a computer program or instructions to perform the method of any of the above aspects. The communication device may be the first communication device in the first aspect or the third aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; alternatively, the communication device may be the second communication device in the second or fourth aspect, or a device including the second communication device, or a device included in the second communication device.

Alternatively, the interface circuit may be a code/data read/write interface circuit, which is used to receive and transmit computer execution instructions (stored in the memory, possibly directly read from the memory, or possibly via other devices) to the processor, so as to make the processor execute the computer execution instructions to execute the method according to any one of the above aspects.

In some possible designs, the communication device may be a chip or a system of chips.

In a ninth aspect, there is provided a communication apparatus comprising: a processor; the processor is configured to be coupled to the memory, and after reading the instructions in the memory, perform the method according to any one of the above aspects. The communication device may be the first communication device in the first aspect or the third aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; alternatively, the communication device may be the second communication device in the second or fourth aspect, or a device including the second communication device, or a device included in the second communication device.

A tenth aspect provides a computer-readable storage medium having stored therein instructions that, when run on a communication device, cause the communication device to perform the method of any of the above aspects. The communication device may be the first communication device in the first aspect or the third aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; alternatively, the communication device may be the second communication device in the second or fourth aspect, or a device including the second communication device, or a device included in the second communication device.

In an eleventh aspect, there is provided a computer program product comprising instructions which, when run on a communication device, enables the communication device to perform the method of any of the above aspects. The communication device may be the first communication device in the first aspect or the third aspect, or a device including the first communication device, or a device included in the first communication device, such as a chip; alternatively, the communication device may be the second communication device in the second or fourth aspect, or a device including the second communication device, or a device included in the second communication device.

In a twelfth aspect, there is provided a communication device (which may be a chip or a system of chips, for example) comprising a processor for implementing the functionality referred to in any of the above aspects. In one possible design, the communication device further includes a memory for storing necessary program instructions and data. When the communication device is a chip system, the communication device may be constituted by a chip, or may include a chip and other discrete devices.

In a thirteenth aspect, a communication system is provided, which comprises the first communication device of the above aspect and the second communication device of the above aspect.

For technical effects brought by any one of the design manners of the fifth aspect to the thirteenth aspect, reference may be made to technical effects brought by different design manners of the first aspect, the second aspect, the third aspect, or the fourth aspect, and details are not repeated herein.

Drawings

Fig. 1 is a block diagram of an implementation of a multi-carrier communication scheme;

FIG. 2 is a schematic diagram of a constellation diagram, a shaping filter, and a grid;

FIG. 3 is a process flow diagram of a V-OFDM technique;

fig. 4 is a schematic architecture diagram of a communication system according to an embodiment of the present application;

fig. 5 is an interaction diagram of multi-carrier communication according to an embodiment of the present disclosure;

fig. 6 is a block diagram of an implementation of multi-carrier communication according to an embodiment of the present disclosure;

fig. 7 is a block diagram of an implementation of another multi-carrier communication provided in an embodiment of the present application;

fig. 8 is a block diagram of an implementation of another multi-carrier communication provided in an embodiment of the present application;

fig. 9 is an interaction diagram of another multi-carrier communication provided in the embodiment of the present application;

fig. 10 is a block diagram of an implementation of another multi-carrier communication provided in an embodiment of the present application;

fig. 11 is a schematic diagram of a simulation result of a block error rate according to an embodiment of the present application;

fig. 12 is a schematic diagram of a simulation result of another block error rate according to an embodiment of the present application;

fig. 13 is a schematic diagram of a simulation result of another block error rate according to an embodiment of the present application;

fig. 14 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 15 is a schematic structural diagram of another communication device according to an embodiment of the present application.

Detailed Description

The present application will be described in further detail below with reference to the accompanying drawings.

This application is intended to present various aspects, embodiments, or features around a system that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Furthermore, a combination of these schemes may also be used.

In addition, in the embodiments of the present application, the word "exemplary" is used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, the term using examples is intended to present concepts in a concrete fashion.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and it can be known by a person of ordinary skill in the art that the technical solution provided in the embodiment of the present application is also applicable to similar technical problems with the evolution of the network architecture and the occurrence of a new service scenario.

Some terms of the embodiments of the present application are explained below to facilitate understanding by those skilled in the art.

1) Carrier wave, radio wave of a specific frequency carrying data. One carrier may be divided into a plurality of subcarriers.

2) A radio channel, also called a channel, is used to indicate a path between a transmitting end and a receiving end in wireless communication. One channel may be divided into a plurality of subchannels. One sub-channel includes one or more sub-carriers, which is not limited in the embodiments of the present application.

3) A multi-carrier communication system includes a transmitter and a receiver. As shown in fig. 1, a transmitter converts data to be transmitted into a plurality of groups of data, and modulates the plurality of groups of data to obtain modulation symbols a ₀ 823060, modulation symbol a _k 823060, 8230modulating symbol a _K-1 . Passing each modulation symbol through a shaping filter to produce a corresponding waveform (i.e., electromagnetic wave), e.g., modulation symbol a ₀ Generating a corresponding waveform through a shaping filter g (t); modulating the symbol a _k Passing through a shaping filter g (t) e ^j2πkΔft Generating a corresponding waveform; modulating the symbol a _K-1 Passing through a shaping filter g (t) e ^{j2π(K-1)Δft} Corresponding waveforms are generated and transmitted together into a wireless channel. The receiver is atThe received waveform in the wireless channel is filtered by a matched filter to obtain a demodulated symbol, for example: matched filtering is carried out through a matched filter gamma (t), and a demodulation symbol a is obtained based on a matched filtering result ₀ (ii) a Passing through a matched filter gamma (t) e ^-j2πkΔft Performing matched filtering to obtain demodulated symbol a based on the result of matched filtering _k (ii) a Passing through a matched filter gamma (t) e ^{-j2π(K-1)Δft} Performing matched filtering to obtain demodulated symbol a based on the result of matched filtering _K-1 . The receiver converts all demodulated symbols into received data. That is, the transmitter synthesizes each modulation symbol through the shaping filter in the time-frequency domain to obtain a transmission signal and transmits the transmission signal, and the receiver analyzes the transmission signal by using the corresponding matched filter after receiving the transmission signal transmitted through the channel to obtain a demodulated signal.

The transmitter may be a transmitting end or be located in a transmitting end. The transmitting end may be, but is not limited to, a terrestrial device or a satellite. The receiver may be a receiving end or be located in a receiving end. The receiving end may be, but is not limited to, a terrestrial device or a satellite.

It is to be understood that a waveform is a graphical abstraction of the distribution of signals/symbols over time or frequency, and in this application, the term "signal" may be used interchangeably with "waveform".

In wireless communications, signals may be communicated in different combinations of different symbols.

As in the multi-carrier communication system of fig. 1, the general form of the signal transmitted by the transmitter into the radio channel, i.e. the complex baseband signal, can be expressed as:

s (t) is the complex baseband signal, k denotes the subcarrier index, l denotes the time index, or time domain pulse interval, a _k，l Denotes a modulation symbol, K denotes the number of subcarriers, g (T) denotes a shaping filter, T _S Indicating the pulse spacing and deltaf the subcarrier spacing.

4) The basic elements of multicarrier communication, as shown in fig. 2, include constellations, shaping filtering, and grids.

Basic elements of multicarrier communication will be described with reference to the form of the complex baseband signal.

The constellation, i.e. the constellation diagram, is used to represent the signals on the complex plane to visually represent the relationship between the signals. The points on the constellation diagram are called constellation points, one constellation point represents one signal, the vector length of the constellation point represents the amplitude of the signal, and the vector angle of the constellation point represents the phase of the signal. In the constellation diagrams of different modulation and demodulation modes, the number of constellation points, the vector length and the vector angle may be different.

The shaping filtering, i.e. the shaping filter, can be understood as a time domain pulse.

The grid may also be referred to as a time-frequency grid. A grid is made up of one time domain pulse in the time domain and one subcarrier in the frequency domain.

The performance of multicarrier communication can be measured by the following indicators: (i) shift orthogonality: the receiver is simple; (ii) time-frequency concentration: the out-of-band attenuation is reduced; (iii) grid packing: the spectrum efficiency is high. G (t-lT) was designed anyway according to Balian-Low theorem _S )e ^j2πkΔft None of these three properties can be satisfied simultaneously. Therefore, the multi-carrier waveform design takes a tradeoff between these three performance metrics.

5) Multicarrier communication techniques, including OFDM, single-carrier frequency-division multiple access (SC-FDMA), filter bank multi-carrier (FBMC), generalized frequency-division multiplexing (GFDM), sub-band filtered orthogonal frequency-division multiplexing (f-OFDM), super-nyquist transmission (FTN), spectral efficiency frequency-division multiplexing (seqq), quadrature Amplitude Modulation (QAM), offset quadrature amplitude modulation (fdm). SC-FDMA introduces Discrete Fourier Transform (DFT) operation to the OFDM modulation symbols before mapping to a single carrier, can reduce the peak-to-average power ratio (PAPR) of OFDM waveforms, and becomes a waveform for uplink transmission in the fourth generation mobile communication system (4 th generation,4 g)/fifth generation mobile communication system (5 th generation,5 g).

The multi-carrier communication technique also includes vector orthogonal frequency-division multiplexing (V-OFDM). The V-OFDM technique maps modulation symbols to multiple subbands, with each subband transmitting one multidimensional vector symbol. One subband may include a plurality of subcarriers.

As shown in fig. 3, a process flow of V-OFDM is shown. With 8 modulation symbols X ₀ 、X ₁ 、……、X ₇ For example, the V-OFDM transmitting end may perform the following processing on the 8 modulation symbols: (i) first and last storage; (ii) Performing 2 4-dimensional Inverse Discrete Fourier Transforms (IDFT); (iii) Reading in front of and behind the column, and outputting the processed x ₀ 、x ₁ 、……、x ₇ 。

"and/or" in the present application, describing an association relationship of associated objects, means that there may be three relationships, for example, a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The plural in the present application means two or more.

In addition, it is to be understood that the terms first, second, etc. in the description of the present application are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order.

The technical scheme of the embodiment of the application can be applied to a mobile communication system and can also be applied to a satellite communication system, wherein the satellite communication system can be fused with a traditional mobile communication system. For example: the mobile communication system may be a 4G communication system (e.g., a Long Term Evolution (LTE) system), a 5G communication system (e.g., a New Radio (NR) system), a future mobile communication system, and the like.

Fig. 4 is a communication system provided in an embodiment of the present application, where the communication system includes at least one network device (e.g., network device 41 shown in fig. 4) and at least one terminal device (e.g., terminal device 42 shown in fig. 4). The network device may send a downlink signal to the terminal device, and the terminal device may send an uplink signal to the network device. Of course, the communication system in the embodiment of the present application may also be applicable to communication between network devices, communication between terminal devices, and communication between car networking, internet of things, industrial internet, and the like.

Optionally, the network device 41 in this embodiment is a device that accesses the terminal device 42 to a wireless network. The network device 41 may be a node in a radio access network, which may also be referred to as a base station, and may also be referred to as a Radio Access Network (RAN) node (or device). For example, the network device 41 may include an evolved Node B (NodeB or eNB or eNodeB) in an LTE system or an evolved LTE system (LTE-Advanced, LTE-a), such as a conventional macro base station eNB and a micro base station eNB in a heterogeneous network scenario; or may also include a next generation Node B (gNB) in the 5G NR system, or may also include a Transmission Reception Point (TRP), a home base station (e.g., home evolved NodeB, or home Node B, HNB), a baseband unit (BBU), a baseband pool BBU point, or a WiFi Access Point (AP), etc.; still alternatively, the system may further include a Centralized Unit (CU) and a Distributed Unit (DU) in a cloud access network (cloudlan) system; or may include a network device in a non-terrestrial network (NTN), that is, the network device may be deployed in an aerial platform or a satellite, and in the NTN, the network device 41 may serve as a layer 1 (L1) relay (relay), or may serve as a base station, or may serve as a DU, or may serve as an Integrated Access and Backhaul (IAB) node, which is not limited in the embodiment of the present application. Of course, the network device 41 may also be a node in the core network.

Optionally, the terminal device 42 in this embodiment may be a device for implementing a wireless communication function, for example, a terminal or a chip that can be used in the terminal. The terminal may be a User Equipment (UE), an access terminal, a terminal unit, a terminal station, a mobile station, a distant station, a remote terminal, a mobile device, a wireless communication device, a terminal agent or a terminal device, etc. in a 5G network or a PLMN which is evolved in the future. The access terminal may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device or a wearable device, a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transport security (transport security), a wireless terminal in city (smart), a wireless terminal in smart home (smart), etc. Alternatively, the terminal may be a terminal (e.g., a vehicle-to-internet Device) in a vehicle-to-electrical (V2X) network, a terminal in a Device-to-Device (Device-to-Device) communication, a terminal in a machine-to-machine (M2M) communication, or the like. The terminal may be mobile or stationary.

Under a BICM transmission system, diversity gain is obtained by configuring time-frequency-space resources, and high-reliability low-delay URLLC communication can be realized. Specifically, a larger bandwidth is configured to implement frequency diversity, a larger time slot is configured to implement time diversity, and a denser antenna is configured to implement space diversity. Wherein the block error rate (BLER) is 10 ^-5 Or lower, high reliability can be ensured, the shaping filter avoids symbol crossing and iterative equalization decoding, and low time delay can be ensured.

Among many multicarrier communication technologies, the OFDM technology carries signals through mutually orthogonal subcarriers, has advantages of simple structure, easy implementation, support of multiple antennas, and the like, and becomes a multicarrier communication technology widely used in LTE or NR systems. The OFDM can ensure low delay to a certain extent, but has low reliability and cannot well meet the requirements of high reliability and low delay.

Based on this, the embodiment of the present application provides a multi-carrier communication method. In the method, a first communication device, as a transmitter, generates a first signal obtained by performing a first process on N modulation symbols, wherein the N modulation symbols are formed by L groups, each group includes M modulation symbols, and N = lxm, and when performing the first process, the first communication device performs M-dimensional DFT on the M modulation symbols of each group to obtain a second signal, and performs an inverse fourier transform on the second signal. Therefore, after the generated first signal is transmitted through a channel, symbols among different groups do not have intersymbol interference, that is, on the basis that the average signal-to-noise ratio is unchanged, the log-likelihood ratio fluctuation of different bits is as small as possible, the reliability is higher, and the requirements of high reliability and low time delay are better met.

The multi-carrier communication method provided by the embodiment of the present application can be applied to the communication system shown in fig. 4. Fig. 5 is a possible multi-carrier communication process, including the steps of:

s501: the first communication device performs first processing on the N modulation symbols to generate a first signal.

In an embodiment of the application, the first communication device is a transmitter. The first communication device may be a network device or a terminal device.

Where N modulation symbols are made up of L groups, each group including M modulation symbols, N = lxm. N, L and M are positive integers. Alternatively, one RB is 12 subcarriers, and N may be an integer multiple of 12, e.g., N =72. It should be noted that, when N takes other values, the reliability of the communication method of the present embodiment is also higher than that of the communication method based on the OFDM technique.

In one possible approach, the first communication device may group the N modulation symbols in different subbands. For example, the first communication device may map N modulation symbols onto L subbands, each subband transmitting an M-dimensional vector, with one packet for each subband. I.e., N modulation symbols are carried by L subbands, each subband being used to carry M modulation symbols. So L groups can be understood as L sub-bands, but also as L vector groups/vector chunks. After passing through a multipath channel, intersymbol interference exists among M symbols in the same vector block, and intersymbol interference does not exist among symbols in different vector blocks. Where the intersymbol interference present between M symbols in the same vector block can be equalized during demodulation.

Optionally, one subband includes a plurality of subcarriers. For example, one subband includes M subcarriers. Each of the N modulation symbols is mapped on M subcarriers at the same time, that is, each subcarrier of the M subcarriers has a component of the modulation symbol, or each subcarrier of the M subcarriers corresponds to a symbol obtained by processing the modulation symbol. For example, if one of the N modulation symbols is changed, the component of the modulation symbol on each of the M subcarriers is changed.

The first processing may include performing M-dimensional DFT on M modulation symbols of each group to obtain the second signal, that is, performing L M-dimensional DFTs. In one possible approach, the first communication device may perform an operation (e.g., multiplication) on the L × M-dimensional modulation symbol matrix and an M-dimensional DFT matrix (e.g., L × M-dimensional DFT matrix) to obtain a matrix of the second signal, where the M-dimensional DFT matrix is not limited. In another possible implementation, when M is 2 or 4, the first communication device may perform an operation on the L × M-dimensional modulation symbol matrix and the L × 2 or L × 4-dimensional matrix to obtain a matrix of the second signal. Each element in the L × 2 or L × 4 dimensional matrix is obtained by addition and subtraction of 2 or 4 modulation symbols, the L × 2 or L × 4 dimensional matrix is not limited herein, and examples of the L × 2 or L × 4 dimensional matrix may be referred to in the following embodiments. It should be noted that the L × 2 or L × 4 dimensional matrix is different from the DFT matrix, but can achieve similar or same effect as the DFT matrix.

Optionally, after obtaining the second signal, the first communication device may map the L M-dimensional symbols in the second signal to M subcarriers simultaneously, that is, each subcarrier of the M subcarriers corresponds to each symbol in the second signal one to one.

The first processing may further include performing an inverse fourier transform on the second signal. For example, the first communication device performs a zero-padding operation, e.g., a (N) padding operation, on the second signal _FFT -N)/2 zeros as N _FFT Inverse Discrete Fourier Transform (IDFT) is the dimension. The frequency domain zero padding may make the time domain signal more continuous. And the transmitter can be compatible with Fast Fourier Transform (FFT) architecture of OFDM, support Multiple Input Multiple Output (MIMO) and multiuser frequency division multiplexing, and the receiver can avoid iterative equalization decoding. Wherein N is _FFT Is a positive integer, optionally, N _FFT May be 1024 or 2048, etc., or N _FFT And may be a power of 2 without limitation.

Optionally, the first processing may further include: before performing M-dimensional DFT on M modulation symbols of each group, phase rotation is performed on N modulation symbols. This makes it possible to make the log-likelihood ratio fluctuation of different bits as small as possible.

Wherein the angle of phase rotation is related to the modulation scheme and the element index M of the modulation symbol, M = 0. For example, the modulation scheme is QAM, and the rotation angle of the modulation symbol of the mth element in the ith group satisfies the following equation:

l-1, representing the rotation angle of the modulation symbol of the mth element of the ith group, i = 0. If the modulation mode is a phase-shift keying (PSK) modulation mode, the rotation angle of the modulation symbol of the mth element in the ith group satisfies the following formula:

r is the number of constellation points.

S502: the first communication device transmits the first signal and the second communication device receives the sixth signal.

The first signal satisfiesThe following equation:

wherein s (t) denotes a first signal, a _l，m Is the modulation symbol of the mth element of the lth group,

means for performing M-dimensional DFT, e on M modulation symbols of the l-th group ^{j2π(kL+l)Δft} Denotes the inverse fourier transform, Δ f is the subcarrier spacing, and Δ f =1/T, T is the symbol period. Optionally, T is compared with T _S The time period of (2) is long.

Alternatively, t may relate to one or more of the following: symbol period T, cyclic prefix duration T _CP Zero padded suffix duration T _ZP Or cyclic suffix duration T _CS . If T is taken as the value of the cyclic prefix duration T _CP In this connection, it is possible to achieve channel multipath interference resistance, and the first signal s (t) has small signal fluctuation and higher communication reliability. If the value of T is equal to the zero-padded suffix duration T _ZP Then channel multipath interference resistance can be achieved and power can be saved. If the value of T is related to the cyclic suffix duration T _CS In this regard, channel multipath interference immunity may be achieved and out-of-band leakage may be reduced.

For example, the t satisfies one of the following: -T _CP ≤t<T，T _CP Is the cyclic prefix duration; or 0. Ltoreq. T<T; or 0. Ltoreq.t<T+T _ZP ，T _ZP Padding a suffix duration for zero; or-T _CP ≤t<T+T _CS ，T _CS Is the cyclic suffix duration. t may be a relative time value. Optionally, T may be T, or T + T _ZP Or T + T _CS 。

In some possible scenarios, e.g., a multi-antenna scenario, precoding is applied on the subcarriers, rather than precoding in OFDM on the modulation symbols. For example, the first communication device precodes on each subcarrier. Correspondingly, the second communication device performs equalization of the multi-antenna interference on each subcarrier.

Optionally, the first communication device transmits symbols in the first signal on M subcarriers. Correspondingly, the second communication device may attempt to receive symbols in the first signal on the M subcarriers.

The sixth signal is a received signal of the first signal after passing through the channel. Specifically, the sixth signal is a received signal obtained by superimposing noise on the first signal after the first signal passes through a channel.

The second communication device may be a receiver. The second communication device may be a network device or a terminal device.

S503: and the second communication device carries out second processing on the sixth signal to obtain N demodulation symbols.

The second communication apparatus can perform the reverse operation processing in S501 with the first communication apparatus, and recover N demodulated symbols.

The second processing includes performing L M-dimensional DFT demapping on the first symbol included in the sixth signal to obtain a third signal. The third signal includes N second symbols, which are formed of L groups, each group including M second symbols. For example, the second processing includes sampling the first symbol included in the sixth signal, and L M-dimensional DFT demapping is performed on the sampled first symbol.

The second processing further includes equalizing the M second symbols in each group. Optionally, equalizing the M second symbols in each group includes phase-rotating equalizing the M second symbols in each group. Wherein the intersymbol interference existing between the M symbols in the same vector chunk can be equalized in the equalization process.

Through the scheme provided by the embodiment of the application, the transmitter executes L M-dimensional DFTs on the modulation symbols firstly, then executes inverse Fourier transform, and the receiving end executes corresponding inverse operation to recover the transmitted signals. After passing through the multipath channel, there is no intersymbol interference between symbols of different groups. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of the multicarrier communication is improved, and the requirements of high reliability and low time delay are met. Compared with the OFDM, the present embodiment further improves the reliability of communication on the basis of ensuring low latency.

On the basis of fig. 5, fig. 6 provides a possible multicarrier communication implementation procedure, including the following steps:

s601: transmitter pairs N modulation symbols a = [ a = [ a ₀ ，a ₁ ，...，a _N-1 ] ^T Carrying out vector grouping to obtain L groups of modulation symbols a = [ a = [) ₀ ，a ₁ ，...，a _L-1 ] ^T Wherein the first subband index contains M modulation symbols a _l ＝[a _lM ，a _lM+1 ，...，a _lM+M-1 ] ^T Value a of the element of the mth element index of the lth sub-band index _l，m Is a _l A in the matrix _lM+m I.e. a _l，m ＝a _lM+m . The N modulation symbols after vector grouping can be represented by a L × M dimensional modulation symbol matrix a.

The L × M dimensional modulation symbol matrix a can be represented as:

wherein a is _l，m Indicating the modulation symbol corresponding to the ith subband index L e {0, 1.,. L-1}, and the mth element index M e {0, 1.,. M-1 }. Operator

Is expressed as being

The matrix a on the left side may be represented by a matrix including an element a on the right side, and a value not representing an element in the matrix a must be a value represented by the element a in the matrix on the right side.

S602: the transmitter performs phase rotation Ψ on elements in the L × M-dimensional modulation symbol matrix a to obtain a phase-rotated L × M-dimensional modulation symbol matrix C.

The phase-rotated L × M-dimensional modulation symbol matrix C may be:

wherein the operator

Representing the Hadamard product (Hadamard) product, Ψ represents an L × M-dimensional phase rotation matrix.

Ψ can be represented as:

for the case of a QAM modulation,

for the case of PSK modulation,

where R represents the number of constellation points. For example, for Binary Phase Shift Keying (BPSK), R =2. For Quadrature Phase Shift Keying (QPSK), R =4. For the case of PSK modulation,

independent of the subband index/.

S603: the transmitter performs M-dimensional DFT on the L × M-dimensional modulation symbol matrix C according to rows to obtain an L × M-dimensional transmission signal matrix V. Here, the L × M-dimensional transmission signal matrix V may be the "second signal" shown in fig. 5.

The L × M dimensional transmission signal matrix V can be expressed as:

wherein F _M Representing an M-dimensional DFT matrix.

Wherein the L × M modulation symbol matrix C can be expressed as：

F _M Can be as follows:

s604: the transmitter performs parallel-to-serial conversion on the L multiplied by M dimensional transmission signal matrix V, and sequentially maps the L multiplied by M dimensional transmission signal matrix V to N = L multiplied by M subcarriers

The corresponding relation before and after parallel-serial conversion is v _mL+l ＝v _l，m I.e. the value V of the element of the mth element index of the lth subband index in the L × M dimensional transmit signal matrix V _l，m Is v in the v matrix _mL+l 。

The elements in the matrix v may adopt v ₀ ，v ₁ ，...，v _N-1 And (4) showing.

S605: the transmitter complements each of the two sides of the signal v on the N sub-carriers (N) _FFT -N)/2 zeros as N _FFT Vitamin IDFT to yield N _FFT Dimensional discrete time signal

Wherein u is determined as follows:

wherein

Represents N _FFT The dimension of the DFT matrix is then determined,

represents (N) _FFT -N)/2-dimensional all-zero element column vector.

Can be as follows:

wherein v is ₀ Common to all (N) _FFT -N)/2 zeros, v _N-1 Then share (N) _FFT -N)/2 zeros.

S606: transmitter pair N _FFT Dimension discrete time signal u plus N _CP A cyclic prefix, to obtain N _FFT +N _CP The discrete-time signal s is measured. The S606 may be resistant to channel multipath interference and may further improve the reliability of the multicarrier communication.

N _FFT +N _CP The dimensional discrete-time signal s can be expressed as:

wherein N is _CP Greater than or equal to N _FFT 。

S607: transmitter pair N _FFT +N _CP The dimension discrete time signal s is subjected to parallel-to-serial conversion (i.e., digital-to-analog conversion) to obtain a continuous time signal s (t). Wherein the continuous-time signal s (t) may be the "first signal" shown in fig. 5.

The continuous-time signal s (t) can be expressed as:

wherein-T _CP ≤t<T, T denotes a symbol period, Δ f denotes a subcarrier spacing, and Δ f =1/T, T _CP Indicating the cyclic prefix duration.

S608: the receiver obtains N after sampling _FFT +N _CP Dimensional discrete time signal

Wherein, the N _FFT +N _CP Dimensional discrete time signal

May be for the "sixth signal" shown in FIG. 5"signal obtained after sampling.

N _FFT +N _CP Dimensional discrete time signal

Can be expressed as:

the sampling process is a process of converting a received continuous signal into a discrete signal. This S608 may be implemented with nyquist sampling. Optionally, the sampling interval T _S Satisfies the following conditions: t is a unit of _S ＝T/N _FFT 。

Therein, in S608, the receiver further performs serial-to-parallel conversion on the received signal.

S609: receiver pair N _FFT +N _CP Dimensional discrete time signal

Remove N _CP A cyclic prefix, to obtain N _FFT Dimensional discrete time signal

N _FFT Dimensional discrete time signal

Can be expressed as:

s610: receiver for N-dimensional discrete time signal

To N _FFT Dimension DFT and extracting frequency domain signals on the middle N subcarriers to obtain

Can be expressed as:

s611: receiver pair receiving signal

Performing vector grouping, wherein the corresponding relation before and after the vector grouping is

Obtaining a L × M dimension received signal matrix

Wherein the content of the first and second substances, the L × M dimensional received signal matrix

May be the "third signal" shown in fig. 5.

L x M dimension received signal matrix

Can be expressed as:

s612: receiver pair L x M dimension received signal matrix

Equalizing respectively according to columns to obtain an L multiplied by M modulation symbol estimation matrix

Outputting an estimate of the transmitted modulation symbol a via parallel-to-serial conversion

The corresponding relation before and after parallel-serial conversion is

Modulation symbol estimation matrix

Can be expressed as:

where S601-S607 are the processing procedures performed by the transmitter and S608-S612 are the processing procedures performed by the receiver.

The multi-carrier communication implementation shown in fig. 6 may be viewed as a V-OFDM based multi-carrier waveform baseband compatible implementation.

By the scheme provided by the embodiment of the application, the transmitter firstly executes L M-dimensional DFTs and then executes 1N DFTs on the modulation symbols _FFT And (4) maintaining IDFT, and the receiving end executes corresponding inverse operation to recover the transmitted signal. After passing through a multipath channel, there is no intersymbol interference between symbols of different vector blocks. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of multicarrier communication is improved, and the requirements of high reliability and low time delay are met. And each modulation symbol is transmitted in M subcarriers at the same time, the transmitter can be compatible with the FFT architecture of OFDM, MIMO and multi-user frequency division multiplexing are supported, and the receiving end avoids iterative equalization decoding. At BLER =10 ^-5 Or the lower working point is lower than the signal-to-noise ratio required by the OFDM with the same Modulation and Coding Scheme (MCS) level, and the requirements of high-reliability low-delay communication are met.

It can be understood that the scheme provided by the embodiment of the present application is also applicable to a single-antenna single-user multicarrier communication scenario.

On the basis of fig. 6, fig. 7 provides a possible multi-carrier communication implementation procedure, which includes the following steps:

S701-S702 can be seen in S601-S602.

Where the vector dimension M =2 in S701 and S702.

S703: the transmitter transforms the L x2 dimensional modulation symbol matrix C to obtain an L x2 dimensional transmission signal matrix V.

The L × 2-dimensional modulation symbol matrix C can be expressed as:

the L × 2 dimensional transmission signal matrix V can be expressed as:

wherein

S704-S712 can be seen in S604-S612.

Aiming at the special condition that the vector dimension M =2, the transmitter can execute L addition and subtraction operations to replace L2-dimensional DFTs, so that complex multiplication operations in the DFT are avoided, the operation complexity is reduced, a DFT module is avoided being deployed, the hardware structure is simplified, and the technical effect similar to the DFT can be realized.

On the basis of fig. 6, fig. 8 provides a possible multi-carrier communication implementation procedure, which includes the following steps:

S801-S802 can be seen in S601-S602.

S803: the transmitter transforms the L x 4 dimensional modulation symbol matrix C to obtain an L x 4 dimensional transmission signal matrix V.

The L × 4-dimensional modulation symbol matrix C may be expressed as:

the L × 4 dimensional transmission signal matrix V can be expressed as:

wherein the content of the first and second substances,

S804-S812 may be seen in S604-S612.

For the special case of vector dimension M =4, the transmitter may perform L addition and subtraction operations instead of L4-dimensional DFT, avoid complex multiplication operations in DFT (complex multiplication j may be regarded as addition and subtraction operations after exchanging real and imaginary parts, and does not need to be implemented by complex multiplication operations), reduce the complexity of operations, avoid deploying DFT modules, simplify the hardware structure, and achieve the technical effect similar to DFT.

The embodiment of the application also provides a possible multi-carrier communication process, which can be suitable for a multi-carrier communication scene with a single antenna and a single user. As shown in fig. 9, the method comprises the following steps:

s901: the first communication device performs third processing on the N modulation symbols to generate a fourth signal.

Where N modulation symbols are made up of L groups, each group including M modulation symbols, N = lxm. N, L and M are positive integers. Optionally, N is an integer multiple of 12, e.g., N =72.

In one possible approach, N modulation symbols are carried by L subbands, each subband being used to carry M modulation symbols. See S501 above, and similar parts are not described in detail.

The third processing may include performing M L-dimensional IDFTs on the N modulation symbols to obtain a fifth signal, and performing shaping filtering on the fifth signal to obtain a fourth signal. The first communication device performs shaping filtering on the fifth signal through a shaping filter, and the shaping filter is not limited herein.

Optionally, the third processing may further include: the N modulation symbols are phase rotated before the M L-dimensional IDFT is performed. This makes it possible to make the log-likelihood ratio fluctuation of different bits as small as possible.

Wherein the angle of the phase rotation is related to the element index M of the modulation scheme and/or modulation symbol, M = 0. E.g. the modulation scheme being QAM, of the l-th groupThe rotation angle of the modulation symbol of the m-th element is 0,l = 0. For another example, the modulation scheme is a PSK modulation scheme, and the rotation angle of the modulation symbol of the mth element in the l-th group satisfies the following formula:

wherein, the first and the second end of the pipe are connected with each other,

the rotation angle of the modulation symbol of the mth element in the ith group is represented, and R is the number of constellation points.

S902: the first communication device transmits the fourth signal and the second communication device receives the seventh signal.

The fourth signal satisfies the following equation:

Optionally, k and m relate to one or more of the following information: cyclic prefix length N _CP Or cyclic suffix length N _CS . If k and m are related to the cyclic prefix length N _CP In this connection, resistance to channel multipath interference can be achieved, and the fourth signal s (t) has small signal fluctuation and high communication reliability. If k and m are the length of the cyclic suffix N _CS In this regard, signal multipath interference immunity may be achieved and out-of-band leakage may be reduced.

For example, k and the m satisfy one of: -N _CP ≤kM+m<LM-1，N _CP Is the cyclic prefix length; or 0. Ltoreq. KM + m<LM-1; or-N _CP ≤kM+m<LM+N _CS -1，N _CS Is the cyclic suffix length. Optionally, kM + m may take the value LM-1, or LM + N _CS -1。

In one possible approach, the shaping filter may be a root-raised-cosine (RRC) filter without intersymbol interference.

Optionally, the first communication device transmits symbols of the fourth signal on L subbands. Correspondingly, the second communication device attempts to receive the symbols of the fourth signal on the L subbands.

The seventh signal is a received signal of the fourth signal after the fourth signal passes through the channel. Specifically, the seventh signal is a received signal obtained by superimposing noise on the fourth signal after the fourth signal passes through a channel.

S903: and the second communication device carries out fourth processing on the seventh signal to obtain N demodulation symbols.

The second communication apparatus may perform the inverse processing operation with the first communication apparatus in S901 to recover N demodulated symbols.

The fourth processing includes performing M L-dimensional DFT demapping on the third symbol included in the seventh signal to obtain an eighth signal. The eighth signal includes N fourth symbols, which are formed of L groups, each group including M fourth symbols. For example, the fourth processing includes sampling a third symbol included in the seventh signal, and performing M L-dimensional DFT demapping on the sampled third symbol.

The fourth processing further includes equalizing the M fourth symbols in each group. Optionally, equalizing the M fourth symbols in each group includes: the M fourth symbols in each group are equalized for phase rotation.

According to the scheme provided by the embodiment of the application, the transmitter firstly executes M L-dimensional IDFTs to the modulation symbols to replace 1N-dimensional IDFT in OFDM, and the receiving end executes corresponding inverse operation to recover the transmitted signals. After passing through a multipath channel, there is no intersymbol interference between symbols of different vector blocks. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of the multicarrier communication is improved, and the requirements of high reliability and low time delay are met. Compared with the OFDM, the present embodiment further improves the reliability of communication on the basis of ensuring low latency.

On the basis of fig. 9, fig. 10 provides a possible multicarrier communication implementation procedure, including the following steps:

s1001: transmitter pairs N modulation symbols a = [ a = [ a ₀ ，a ₁ ，...，a _N-1 ] ^T Vector grouping is carried out to obtain L groups of modulation symbols a = [ a ] ₀ ，a ₁ ，...，a _L-1 ] ^T Wherein the first subband index contains M modulation symbols a _l ＝[a _lM ，a _lM+1 ，...，a _lM+M-1 ] ^T Value a of the element of the mth element index of the lth sub-band index _l，m Is a _l A in the matrix _lM+m I.e. a _l，m ＝a _lM+m . The N modulation symbols after vector grouping may be represented by a L × M dimensional modulation symbol matrix a.

The L × M dimensional modulation symbol matrix a may be represented as:

wherein a is _l，m Indicating the modulation symbol corresponding to the ith subband index L e {0, 1.,. L-1}, and the mth element index M e {0, 1.,. M-1 }.

S1002: the transmitter performs phase rotation Θ on elements in the L × M-dimensional modulation symbol matrix a to obtain an L × M-dimensional modulation symbol matrix B after phase rotation.

The phase-rotated L × M-dimensional modulation symbol matrix B may be:

wherein the operator

Representing a Hadamard product and theta a phase rotation matrix of dimension L x M.

Θ can be expressed as:

for the purpose of QAM modulation,

for the case of PSK modulation,

s1003, carrying out: and the transmitter performs L-dimensional IDFT on the L × M-dimensional modulation symbol matrix B according to the columns to obtain an L × M-dimensional transmission signal matrix T. Here, the L × M-dimensional transmission signal matrix T may be "fifth signal" shown in fig. 9.

The L × M dimensional transmission signal matrix T can be expressed as: f _L Representing L-dimensional DFT matrix, operator (.) ^H Representing the conjugate transpose of the matrix.

F _L Can be as follows:

b can be represented as:

s1004: the transmitter performs parallel-to-serial conversion on the L multiplied by M dimensional transmission signal matrix T to obtain an N dimensional discrete time signal

The corresponding relation before and after parallel-serial conversion is t _lM+m ＝t _l，m I.e. the value T of the element of the mth element index of the L subband index in the L × M dimensional transmission signal matrix T _l，m Is t in the t matrix _lM+m 。

S1005: transmitter adding N to N-dimensional discrete time signal t _CP A cyclic prefix to obtain N + N _CP The time signal s is discrete in dimension. The S1005 may be resistant to channel multipath interference and may improve reliability of multicarrier communication.

N+N _CP The dimension discrete-time signal s can be expressed as:

s1006: the transmitter will transmit N + N _CP The dimension discrete time signal s is passed through a shaping filter g (t) to obtain a continuous time signal s (t). Wherein the continuous-time signal s (t) may be the "fourth signal" shown in fig. 9.

The continuous-time signal s (t) can be expressed as:

wherein T is _S Representing a sampling time interval.

S1007: the receiver obtains N + N after matched filtering and sampling _CP Dimensional discrete time signal

Wherein, the N + N _CP Dimensional discrete time signal

May be for the "seventh signal" shown in FIG. 9 and carrying out matched filtering and sampling to obtain a signal.

N+N _CP Dimensional discrete time signal

Can be expressed as:

s1008: receiver pair N + N _CP Dimensional discrete time signal

Remove N _CP A cyclic prefix to obtain an N-dimensional discrete time signal

N-dimensional discrete time signal

Can representComprises the following steps:

s1009: receiver for N-dimensional discrete time signal

Obtaining a L × M dimension received signal matrix

L x M dimension received signal matrix

Can be expressed as:

s1010: receiver pair L x M dimension received signal matrix

After L-dimension DFT is carried out according to columns, an L multiplied by M-dimension receiving signal matrix is obtained

Wherein the L × M dimensional received signal matrix

May be the "eighth signal" shown in fig. 9.

L x M dimension received signal matrix

Can be expressed as:

s1011: receiver pair L x M dimension received signal matrix

Performing channel estimation and equalization to obtain an L × M modulation symbol estimation matrix

The corresponding relation before and after parallel-serial conversion is

L x M dimension received signal matrix

Can be expressed as:

LxM dimensional modulation symbol estimation matrix

Can be expressed as:

where S1001-S1006 are processes performed by the transmitter and S1007-S1011 are processes performed by the receiver.

The multi-carrier communication implementation shown in fig. 9 may be viewed as a V-OFDM based multi-carrier waveform independent compatible implementation. The scheme provided by the embodiment of the application is also suitable for a single-antenna single-user multi-carrier communication scene.

According to the scheme provided by the embodiment of the application, the transmitter firstly executes M L-dimensional IDFTs on modulation symbols to replace 1N-dimensional IDFT in OFDM, and the receiving end executes corresponding inverse operation to recover the transmitted signals.After passing through a multipath channel, intersymbol interference exists between the M symbols of the same vector block, and intersymbol interference does not exist between the symbols of different vector blocks. By changing the corresponding relation between the modulation symbol and the subcarrier, the log-likelihood ratio fluctuation of different bits is reduced as much as possible on the basis that the average signal-to-noise ratio is kept unchanged, the reliability of multicarrier communication is improved, and the requirements of high reliability and low time delay are met. And, the transmitter complexity is simpler than OFDM, the receiving end avoids the iterative equilibrium decoding. At BLER =10 ^-5 Or the lower working point is lower than the signal to noise ratio required by the OFDM with the same MCS level, and the requirement of high-reliability low-delay communication is met.

In the embodiment of the present application, a special case of the implementation process of multi-carrier communication shown in fig. 5 and fig. 6 can be seen, that is, N is _FFT If = N, the multicarrier communication procedure in fig. 9 and 10 is similar to the multicarrier communication procedure in fig. 5 and 6.

It should be noted that, in the implementations shown in fig. 5 (and fig. 6, 7, and 8) and fig. 9 (and 10), the obtained discrete-time signals are the same at the same baseband sampling frequency, but the obtained continuous-time complex baseband signals are different (e.g., the first signal in fig. 5 is different from the fourth signal in fig. 9), and thus they cannot be equivalently represented. In addition, in each embodiment of the present application, the processing procedure and the equalization method (for example, zero forcing detection, minimum mean square error detection, maximum likelihood detection, and the like) of the receiver (or the second communication device) are not limited.

It will be appreciated that the embodiments of the present application provide only a general form of signal expression and do not preclude suitable variations therefrom.

The multi-carrier communication method provided by the embodiments of the present application can be implemented based on a V-OFDM technology, and can also be implemented based on an improved V-OFDM technology.

The following describes, with reference to simulation results, the multi-carrier communication method provided in the embodiment of the present application and the BLER of the communication method based on OFDM and SC-FDMA, respectively.

As shown in fig. 11, in the C-type (CDL-C) channel model of the clustered delay line, the expected delay spread is 300 nanoseconds (ns), the subcarrier spacing (SCS) is 30 kilohertz (kHz), the modulation scheme is QPSK, the Code Rate (CR) of the LDPC (low-density parity-check) is 0.5, and in the case of single-user single-antenna single-stream transmission (1tx1rx, 1layer, 1ue), the multicarrier communication method provided in the embodiment of the present application has an r lower by 0.4 decibels (dB) than OFDM and an r lower by 0.9dB than SC-FDMA.

As shown in fig. 12, in the case that CDL-C is 300ns, SCs is 30kHz, the modulation scheme is QPSK, LDPC CR is 0.5, and single-user multi-antenna multi-stream transmission (2tx2rx, 2layer, 1ue), BLER of the multicarrier communication method provided in the embodiment of the present application is 0.9dB lower than OFDM and 1.1dB lower than SC-FDMA.

As shown in fig. 13, in the case that CDL-C is 300ns, SCs is 30kHz, the modulation scheme is QPSK, LDPC CR is 0.5, and multi-user multi-antenna multi-stream transmission (4 tx2rx,2layer, 2ue), the BLER of the multi-carrier communication method provided in the embodiment of the present application is 0.6dB lower than OFDM and 0.9dB lower than SC-FDMA.

From the comparison, it can be seen that the BLER operating point is 10 for the URLLC scene ^-5 Or lower), the multi-carrier communication method provided in the embodiments of the present application employs Maximum Likelihood (ML) detection, which is steeper than the BLER slope of OFDM, and the larger the frequency selective fading is, the lower the BLER operating point is, and the more significant the required signal to noise ratio (SNR) gain is. It can be seen that the multi-carrier communication scheme provided by the application has higher reliability on the basis of ensuring low time delay.

In addition to OFDM and SC-FDMA, in the 5G standard process, a series of time-frequency non-orthogonal waveform schemes and super-nyquist transmission schemes are formed around different design schemes of constellation diagrams, shaping filtering and time-frequency grids in the multi-carrier technology. The partial waveform scheme and its typical characteristics are shown in table 1 below.

TABLE 1

As can be seen from table 1, FTN has intersymbol interference between all time domain pulses, and SEFDM has intercarrier interference between all subcarriers, thereby increasing the complexity of receiver equalization. In the multi-carrier communication method provided by the application, only intersymbol interference exists between symbols in the group, namely, only interference exists between partial subcarriers and partial time domain pulses. Therefore, compared with the FTN and the SEFDM, the present application can reduce intersymbol interference and inter-subcarrier interference, thereby reducing the complexity of receiver equalization.

The forming filters of GFDM, FBMC and f-OFDM have the problem of symbol crossing and cannot meet the requirement of low time delay. The shaping filter can avoid symbol crossing and can meet the requirement of low time delay.

In the Turbo equalization mode in the related technology, iterative equalization decoding is adopted for serial/parallel interference elimination, and the requirement of low time delay cannot be met. The application port can avoid adopting iterative equalization decoding, and can meet the requirement of low time delay.

Therefore, compared with other time-frequency non-orthogonal waveform schemes and beyond Nyquist transmission schemes, the method has the advantages that the method is obvious in improvement.

In the embodiments of the present application, under a high-reliability low-delay scenario, the provided multicarrier communication scheme makes log-likelihood ratio fluctuations of different bits as small as possible on the basis that an average signal-to-noise ratio remains unchanged. By taking the multi-carrier communication scheme provided by the embodiment of the application as an example based on the V-OFDM technology, the precoding idea among V-OFDM sub-carriers can be used for precoding among antennas and codebook design of URLLC scene MIMO-OFDM. For codebook-based precoding (also called non-transparent transmission), in codebook design, a phase rotation and a DFT matrix with the same number of dimensions of transmission streams can be additionally introduced on the basis of an original codebook. For precoding based on a non-codebook (also called transparent transmission), when a precoding matrix is designed, a phase rotation and a DFT matrix with the same number of transmission streams can be additionally introduced on the basis of an original precoding matrix.

The ideas of phase rotation and DFT matrix are introduced into the precoding between MIMO-OFDM antennas and the precoding between V-OFDM subcarriers in advance, and are mutually related and different. The orthogonality among different subcarriers of the V-OFDM channel exists, a sending end does not need to know the channel in advance, and the performance gain can be obtained by utilizing the frequency selectivity of the channel. However, the MIMO-OFDM channel has natural broadcast characteristics among different antennas, and when the method is used for precoding, a transmitting end needs to know the channel in advance, otherwise, additionally introduced phase rotation and DFT matrix may generate negative gain. Of course, the MIMO-V-OFDM precoding scheme can also be further designed by combining the multi-antenna precoding of MIMO-OFDM and the precoding of V-OFDM subcarriers.

In the embodiments of the present application, unless otherwise specified or conflicting with respect to logic, the terms and/or descriptions in different embodiments have consistency and may be mutually cited, and technical features in different embodiments may be combined to form a new embodiment according to their inherent logic relationship.

It is to be understood that, in the above embodiments, the method and/or the steps implemented by the first communication apparatus may also be implemented by a component (e.g., a chip or a circuit) applicable to the first communication apparatus, and the method and/or the steps implemented by the second communication apparatus may also be implemented by a component applicable to the second communication apparatus.

The multi-carrier communication method of the embodiment of the present application is described in detail above with reference to fig. 5 to fig. 13, and based on the same technical concept as that of the multi-carrier communication method, the embodiment of the present application further provides a communication apparatus, as shown in fig. 14, where the communication apparatus 1400 includes a processing unit 1401 and a transceiver unit 1402, and the apparatus 1400 may be configured to implement the method described in the embodiment of the foregoing method.

In one embodiment, the apparatus 1400 is applied to a first communication apparatus, which is a transmitter.

Specifically, the processing unit 1401 is configured to generate a first signal, where the first signal is obtained by performing first processing on N modulation symbols, where the N modulation symbols are formed by L groups, each group includes M modulation symbols, the first processing includes performing M-dimensional Discrete Fourier Transform (DFT) on the M modulation symbols in each group to obtain a second signal, and performing inverse fourier transform on the second signal, where N = L × M;

the transceiver 1402 is configured to transmit the first signal.

In one implementation, each modulation symbol is mapped on M subcarriers simultaneously.

In one implementation, the first processing further includes: before performing M-dimensional DFT on M modulation symbols of each group, the N modulation symbols are phase-rotated.

I.e. the processing unit 1402, is further configured to perform phase rotation on the N modulation symbols before performing M-dimensional DFT on the M modulation symbols in each group, respectively.

In one implementation, the angle of the phase rotation is related to the modulation scheme and the element index M of the modulation symbol, M = 0.

In one implementation, the modulation scheme is a Quadrature Amplitude Modulation (QAM) scheme, and the rotation angle of the modulation symbol of the mth element in the ith group satisfies the following formula:

l-1, representing the rotation angle of the modulation symbol of the mth element of the ith group, i =0,; or alternatively

The modulation mode is a Phase Shift Keying (PSK) modulation mode, and the rotation angle of the modulation symbol of the mth element in the ith group meets the following formula:

r is the number of constellation points.

In one implementation, the first signal satisfies the following equation:

In one implementation, the t is related to one or more of the following information: symbol period T, cyclic prefix duration T _CP Zero padding suffix duration T _ZP Or cyclic suffix duration T _CS 。

In one implementation, the t satisfies one of: -T _CP ≤t<T，T _CP Is the cyclic prefix duration; or 0. Ltoreq. T<T; or 0. Ltoreq. T<T+T _ZP ，T _ZP Padding a suffix duration for zero; or-T _CP ≤t<T+T _CS ，T _CS Is the cyclic suffix duration.

In another embodiment, the apparatus 1400 is applied to a second communication apparatus, which is a receiver.

Specifically, the transceiver 1402 is configured to receive a sixth signal, where the sixth signal is a received signal of the first signal after passing through a channel;

the processing unit 1401 is configured to perform second processing on the sixth signal to obtain N demodulated symbols, where the second processing includes performing discrete fourier transform DFT demapping on a first symbol included in the sixth signal to obtain a third signal, where the third signal includes N second symbols, the N second symbols are formed by L groups, each group includes M second symbols, and M second symbols in each group are equalized, where N = L × M.

In one implementation, the equalizing the M second symbols in each group includes phase-rotated equalizing the M second symbols in each group.

I.e. the processing unit 1401, is specifically configured to perform phase-rotated equalization on the M second symbols in each group.

In yet another embodiment, the apparatus 1400 is applied to a first communication apparatus, which is a transmitter.

Specifically, the processing unit 1401 is configured to generate a fourth signal, where the fourth signal is obtained by performing third processing on N modulation symbols, where the N modulation symbols are formed by L groups, each group includes M modulation symbols, and the third processing includes performing M L-dimensional Inverse Discrete Fourier Transform (IDFT) to obtain a fifth signal, and performing shaping filtering on the fifth signal, where N = lxm;

the transceiver 1402 is configured to transmit the fourth signal.

In one implementation, the third processing further includes: performing phase rotation on the N modulation symbols before performing M L-dimensional IDFTs.

In one implementation, the angle of the phase rotation is related to the element index M of the modulation scheme and/or modulation symbol, M = 0.

In one implementation, the modulation scheme is a Quadrature Amplitude Modulation (QAM) scheme, and a rotation angle of a modulation symbol of an m-th element of the L-th group is 0,l = 0.. L-1; or

In one implementation, the fourth signal satisfies the following equation:

In one implementation, the k and the m relate to one or more of the following information: cyclic prefix length N _CP Or cyclic suffix length N _CS 。

In one implementation, the k and the m satisfy one of: -N _CP ≤kM+m<LM-1，N _CP Is the cyclic prefix length; or 0. Ltoreq. KM + m<LM-1; or-N _CP ≤kM+m<LM+N _CS -1，N _CS Is the cyclic suffix length.

In yet another embodiment, the apparatus 1400 is applied to a second communication apparatus, which is a receiver.

Specifically, the transceiver 1402 is configured to receive a seventh signal, where the seventh signal is a received signal of the fourth signal after passing through a channel;

the processing unit 1401 is configured to perform fourth processing on the seventh signal to obtain N demodulated symbols, where the fourth processing includes performing discrete fourier transform DFT demapping on a third symbol included in the seventh signal to obtain an eighth signal, where the eighth signal includes N fourth symbols, the N fourth symbols are formed by L groups, each group includes M fourth symbols, and M fourth symbols in each group are equalized, where N = lxm.

In one implementation, the equalizing the M fourth symbols in each group includes: the M fourth symbols in each group are equalized for phase rotation.

In one implementation, the fourth signal satisfies the following equation:

wherein s (t) represents the fourth signal, a _l，m For the modulation symbol of the M-th element of the L-th group, M = 0., M-1, L =0, \8230l-1, e ^j2πkl/L Denotes IDFT, g (T) is a shaping filter, T _S Is the sampling time interval.

It should be noted that, the division of the modules in the embodiments of the present application is schematic, and is only a logical function division, and in actual implementation, there may be another division manner, and in addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or may exist alone physically, or two or more units are integrated in one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

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

Based on the same technical concept as the above-mentioned multi-carrier communication method, as shown in fig. 15, the embodiment of the present application further provides a schematic structural diagram of a communication apparatus 1500. The apparatus 1500 may be used to implement the methods described in the method embodiments above.

The apparatus 1500 includes one or more processors 1501. The processor 1501 may be a general-purpose processor, a special-purpose processor, or the like. For example, a baseband processor, or a central processor. The baseband processor may be used to process communication protocols and communication data, and the central processor may be used to control a communication device (e.g., a base station, a terminal, or a chip), execute a software program, and process data of the software program. The communication device may include a transceiving unit to enable input (reception) and output (transmission) of signals. For example, the transceiver unit may be a transceiver, a radio frequency chip, or the like.

The apparatus 1500 includes one or more processors 1501, which one or more processors 1501 can implement the methods described in the illustrated embodiments described above.

Optionally, the processor 1501 may also implement other functions besides the methods of the above-described illustrated embodiments.

Alternatively, in one design, the processor 1501 may execute instructions that cause the apparatus 1500 to perform the methods described in the method embodiments above. The instructions may be stored in whole or in part within the processor, such as instructions 1503, or in whole or in part in a memory 1502 coupled to the processor, such as instructions 1504, or may collectively cause the apparatus 1500 to perform the methods described in the above method embodiments, via

instructions

1503 and 1504.

In yet another possible design, the communication apparatus 1500 may also include a logic circuit, which may implement the method described in the foregoing method embodiment.

In yet another possible design, the apparatus 1500 may include one or more memories 1502 having instructions 1504 stored thereon that are executable on the processor to cause the apparatus 1500 to perform the methods described in the method embodiments above. Optionally, the memory may further store data therein. Instructions and/or data may also be stored in the optional processor. For example, the one or more memories 1502 may store the corresponding relations described in the above embodiments, or the related parameters or tables referred to in the above embodiments, and the like. The processor and the memory may be provided separately or may be integrated together.

In yet another possible design, the device 1500 may also include a transceiver 1505 and an antenna 1506. The processor 1501 may be referred to as a processing unit, and controls a device (terminal or base station). The transceiver 1505 can be called as a transceiver, a transceiver circuit, an input/output interface circuit or a transceiver unit, etc. for implementing the transceiving function of the device through the antenna 1506.

It should be noted that the processor in the embodiments of the present application may be an integrated circuit chip having signal processing capability. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The Processor may be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, or discrete hardware components. The various methods, steps, and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software modules may be located in ram, flash, rom, prom, or eprom, registers, etc. as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor.

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. The volatile Memory may be a Random Access Memory (RAM) which serves as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic random access memory (Synchronous DRAM, SDRAM), double Data Rate Synchronous Dynamic random access memory (DDR SDRAM), enhanced Synchronous SDRAM (ESDRAM), synchronous link SDRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

Embodiments of the present application also provide a computer-readable medium, on which a computer program is stored, where the computer program, when executed by a computer, implements the method described in the above method embodiments.

The embodiments of the present application further provide a computer program product, and when executed by a computer, the computer program product implements the method described in the foregoing method embodiments.

The embodiment of the application also provides a communication system, which comprises a first communication device and a second communication device. The first communication device may implement the method described in the above method embodiment, and the second communication device may implement the method described in the above method embodiment.

Optionally, the first communication device is a transmitter, and the second communication device is a receiver.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware, or any combination thereof. When implemented in software, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., digital Video Disk (DVD)), or a semiconductor medium (e.g., solid State Disk (SSD)), among others.

The embodiment of the application also provides a processing device, which comprises a processor and an interface; the processor is configured to execute the method described in the above method embodiment.

It should be understood that the processing device may be a chip, the processor may be implemented by hardware or software, and when implemented by hardware, the processor may be a logic circuit, an integrated circuit, or the like; when implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory, which may be integrated in the processor, located external to the processor, or stand-alone.

Those of ordinary skill in the art will appreciate that the various illustrative components and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the components and steps of the various examples have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the technical solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

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

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

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

Through the above description of the embodiments, those skilled in the art will clearly understand that the present application can be implemented in hardware, firmware, or a combination thereof. When implemented in software, the functions described above may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. Taking this as an example but not limiting: computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Furthermore. Any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, a server, or other remote sources using a coaxial cable, a fiber optic cable, a twisted pair, a Digital Subscriber Line (DSL), or a wireless technology such as infrared, radio, and microwave, the coaxial cable, the fiber optic cable, the twisted pair, the DSL, or the wireless technology such as infrared, radio, and microwave are included in the fixation of the medium. Disk (Disk) and disc (disc), as used herein, includes Compact Disc (CD), laser disc, optical disc, digital Versatile Disc (DVD), floppy Disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

In short, the above description is only a preferred embodiment of the present disclosure, and is not intended to limit the scope of the present disclosure. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A multi-carrier communication method, comprising:

a first communication device generates a first signal, wherein the first signal is obtained by performing first processing on N modulation symbols, each of the N modulation symbols is composed of L groups, each group includes M modulation symbols, the first processing includes performing M-dimensional Discrete Fourier Transform (DFT) on the M modulation symbols in each group to obtain a second signal, and performing inverse fourier transform (N = lxm) on the second signal;

the first communication device transmits the first signal.

2. The method of claim 1, wherein each modulation symbol is mapped on M subcarriers simultaneously.

3. The method of claim 1 or 2, wherein the first processing further comprises: before performing M-dimensional DFT on M modulation symbols of each group, the N modulation symbols are phase-rotated.

4. The method of claim 3, wherein an angle of the phase rotation is related to a modulation scheme and an element index M of a modulation symbol, M = 0.

5. The method of claim 4, wherein the modulation scheme is a Quadrature Amplitude Modulation (QAM) scheme, and a rotation angle of the modulation symbol of the mth element of the l-th group satisfies the following equation:

l-1, representing the rotation angle of the modulation symbol of the mth element of the ith group, i =0,; or

r is the number of constellation points.

6. The method of any one of claims 1-5, wherein the first signal satisfies the following equation:

means for performing M-dimensional DFT, e on M modulation symbols of the l-th group ^{j2π(kL+l)Δft} Representing the inverse fourier transform, Δ f is the subcarrier spacing, and Δ f =1/T, T is the symbol period.

7. The method of claim 6, wherein t is related to one or more of the following information: symbol period T, cyclic prefix duration T _CP Zero padded suffix duration T _ZP Or cyclic suffix duration T _CS 。

8. A multi-carrier communication method, comprising:

a second communication device receives a sixth signal, wherein the sixth signal is a received signal of the first signal after passing through a channel;

the second communication device performs second processing on the sixth signal to obtain N demodulated symbols, where the second processing includes performing Discrete Fourier Transform (DFT) demapping on a first symbol included in the sixth signal to obtain a third signal, where the third signal includes N second symbols, the N second symbols are formed by L groups, each group includes M second symbols, and M second symbols in each group are equalized, where N = lxm.

9. The method of claim 8, wherein the equalizing the M second symbols in each group comprises phase-rotated equalizing the M second symbols in each group.

10. A communication device, comprising a processing unit and a transceiving unit;

the processing unit is configured to generate a first signal, where the first signal is obtained by performing first processing on N modulation symbols, where the N modulation symbols are formed by L groups, each group includes M modulation symbols, the first processing includes performing M-dimensional Discrete Fourier Transform (DFT) on the M modulation symbols in each group to obtain a second signal, and performing inverse fourier transform on the second signal, where N = lxm;

the transceiver unit is configured to transmit the first signal.

11. The apparatus of claim 10, wherein each modulation symbol is mapped on M subcarriers simultaneously.

12. The apparatus of claim 10 or 11, wherein the first process further comprises: before performing M-dimensional DFT on M modulation symbols of each group, the N modulation symbols are phase-rotated.

13. The apparatus of claim 12, wherein an angle of the phase rotation is related to a modulation scheme and an element index M of a modulation symbol, M = 0.

14. The apparatus of claim 13, wherein the modulation scheme is a Quadrature Amplitude Modulation (QAM) scheme, and a rotation angle of the modulation symbol of the mth element of the l-th group satisfies the following equation:

r is the number of constellation points.

15. The apparatus of any of claims 10-14, wherein the first signal satisfies the following equation:

wherein s (t) denotes the first signal, a _l，m Is the modulation symbol of the mth element of the l-th group,

16. The apparatus of claim 15, wherein the t is related to one or more of the following information: symbol period T, cyclic prefix duration T _CP Zero padding suffix duration T _ZP Or cyclic suffix duration T _CS 。

17. A communication apparatus, comprising a processing unit and a transceiving unit;

the transceiver unit is configured to receive a sixth signal, where the sixth signal is a received signal of the first signal after passing through a channel;

the processing unit is configured to perform second processing on the sixth signal to obtain N demodulated symbols, where the second processing includes performing Discrete Fourier Transform (DFT) demapping on a first symbol included in the sixth signal to obtain a third signal, where the third signal includes N second symbols, the N second symbols are formed by L groups, each group includes M second symbols, and M second symbols in each group are equalized, where N = lxm.

18. The apparatus of claim 17, wherein the equalizing the M second symbols in each group comprises phase-rotated equalizing the M second symbols in each group.

19. A communication apparatus, characterized in that the communication apparatus comprises: a processor;

the processor to read a computer program or instructions stored in the memory and execute the computer program or instructions to cause the communication apparatus to perform the method of any one of claims 1-7 or to cause the communication apparatus to perform the method of any one of claims 8-9.

20. A communication apparatus, characterized in that the communication apparatus comprises: a processor and interface circuitry;

the interface circuit is used for communicating with a module outside the communication device;

the processor is for executing a computer program or instructions to cause the communication device to perform the method of any of claims 1-7 or to cause the communication device to perform the method of any of claims 8-9.

21. The communication device of claim 20, wherein the communication device is a chip or a system of chips.

22. A computer-readable storage medium comprising a computer program or instructions which, when run on a computer, causes the method of any of claims 1-7 to be performed, or causes the method of any of claims 8-9 to be performed.

23. A computer program product enabling the method of any one of claims 1 to 7 to be performed or enabling the method of any one of claims 8 to 9 to be performed when the computer program product runs on a computer.