CN112398773B

CN112398773B - Data transmission method and device

Info

Publication number: CN112398773B
Application number: CN201910755207.2A
Authority: CN
Inventors: 袁世通; 刘凤威; 黄煌
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-08-15
Filing date: 2019-08-15
Publication date: 2022-05-10
Anticipated expiration: 2039-08-15
Also published as: WO2021027901A1; CN112398773A

Abstract

The embodiment of the application provides a data transmission method and a device thereof, wherein the method comprises the following steps: a sending end modulates and phase rotates a bit stream to obtain a first data stream; filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth; further, the sending end processes the second data stream to obtain a transmission data stream, and sends the transmission data stream. By adopting the embodiment of the application, the peak-to-average ratio of the transmission data can be reduced.

Description

Data transmission method and device

Technical Field

The embodiment of the application relates to the technical field of communication, in particular to a data transmission method and a data transmission device.

Background

The wireless signal is observed from a time domain as a sine wave with continuously changing amplitude, the amplitude is not constant, the amplitude peak value of the signal in one period is different from the amplitude peak value in other periods, and therefore the average power and the peak value power of each period are different. In a longer time, the peak power is the maximum transient power that appears with a certain probability, usually this probability is 0.01%, and the ratio of the peak power to the total average power of the system at this probability is the peak to average power ratio (PAPR), which is called peak-to-average ratio for short.

Signals of a wireless communication system are transmitted to a remote place and need to be power-amplified. Because the dynamic range of a general power amplifier is limited, a signal with a large PAPR easily enters a non-linear region of the power amplifier, resulting in non-linear distortion of the signal and further causing a serious performance degradation of the whole system. Therefore, how to reduce the PAPR of the signal is an urgent technical problem to be solved.

Disclosure of Invention

The embodiment of the application provides a data transmission method and a device thereof, which can reduce the PAPR of the transmitted data.

A first aspect of an embodiment of the present application provides a data transmission method, including:

modulating and phase rotating a bit stream to obtain a first data stream;

and filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth.

In the first aspect of the embodiment of the present application, a sending end is a process of processing a bitstream, where the sending end may be a network device or a terminal device. The second bandwidth is smaller than the first bandwidth through the filtering process, thereby reducing the PAPR of the transmission data.

Further, after the second data stream is obtained, the second data stream is processed to obtain a transmission data stream, and the transmission data stream is sent. The bandwidth of the transmission data stream is smaller than that of the bit stream, thereby reducing the PAPR of the transmission data stream.

The first data stream includes a plurality of first data, each first data carries n bits, and n is a positive integer greater than 1, so that spectrum efficiency can be improved.

In a possible implementation manner, a terminal device or a network device modulates a bit stream by using a modulation manner to obtain a modulated data stream, where the modulated data stream includes a plurality of modulated data, and the modulated data is a real number; and performing phase rotation on the modulated data stream to obtain a first data stream, wherein the first data stream comprises a part of complex numbers of first data. Modulation and phase rotation are performed, and the PAPR can be suppressed.

The modulation mode may be 4-order, 8-order or higher-order pulse amplitude modulation, and if the modulation mode is 4-order pulse amplitude modulation, each first data carries 2 bits; if the modulation mode is 8-order pulse amplitude modulation, each first data carries 3 bits; if the modulation scheme is 16-order pulse amplitude modulation, each first data carries 4 bits. The phase rotation factor of the phase rotation may be denoted as e^k×j×ωWhere ω is the phase and may be π @2 or pi/4, etc.; k is an index of modulation data, and may be numbered from "0" or "1". If the sending end is network equipment, the network equipment can inform the terminal equipment of the adopted modulation mode; if the sending end is a terminal device, the terminal device may modulate the bit stream by using a modulation mode indicated by the network device.

In one possible implementation manner, the terminal device may receive first processing indication information before modulating and phase-rotating the first bit stream, where the first processing indication information is used for indicating a modulation method for modulating the bit stream, and the bit stream is modulated and phase-rotated according to the modulation method. The first processing indication information may be configured for the terminal device by the network device, and the terminal device modulates and phase-rotates the first bit stream according to the first processing indication information, so that the network device can perform corresponding demodulation when receiving the transmission data stream. In this way, the sending end for transmitting the data stream is a terminal device, the receiving end for transmitting the data stream is a network device, and the terminal device sends the transmission data stream to the network device, corresponding to an uplink transmission scenario.

The terminal equipment modulates the bit stream by adopting a modulation mode indicated by the first processing indication information to obtain a modulated data stream, wherein the modulated data stream comprises a plurality of modulated data, and the modulated data is a real number; and performing phase rotation on the modulated data stream to obtain a first data stream, wherein the first data stream comprises a part of complex numbers of first data. Modulation and phase rotation are performed, and the PAPR can be suppressed.

The terminal device may modulate according to the modulation method indicated by the first processing indication information, or may modulate according to a default modulation method, where the default modulation method may be agreed by a protocol, or may be notified to the terminal device by the network device in advance through another method.

In a possible implementation manner, the terminal device may receive second processing indication information before performing the filtering processing on the first data stream, where the second processing indication information is used to indicate a parameter for performing the filtering processing on the first data stream, that is, to indicate how to perform the filtering processing on the first data stream. And the terminal equipment carries out filtering processing on the first data stream according to the second processing indication information to obtain a second data stream, and the filtering processing realizes frequency domain truncation so that the bandwidth of the second data stream is smaller than that of the first data stream, thereby being beneficial to reducing the PAPR.

The second processing instruction information and the first processing instruction information may be carried in the same message or may be carried in different messages.

If the sending end is a network device, the network device can inform the terminal device of the parameters of the filtering processing; if the sending end is the terminal device, the terminal device may perform filtering processing according to the second processing instruction information sent by the network device.

In a possible implementation manner, the second processing indication information includes one or more of first bandwidth indication information, second bandwidth indication information, or a ratio between the first bandwidth and the second bandwidth, where the first bandwidth indication information is used to indicate the first bandwidth, and the second bandwidth indication information is used to indicate the second bandwidth and/or a center frequency point of the second bandwidth.

And if the first bandwidth indication information and the second bandwidth indication information are included, performing frequency domain truncation on the first data stream according to the first bandwidth and the second bandwidth, so that the bandwidth of the second data stream is the second bandwidth.

And if the first bandwidth indication information and the ratio between the first bandwidth and the second bandwidth are included, determining the second bandwidth according to the first bandwidth and the ratio, and performing frequency domain truncation to enable the bandwidth of the second data stream to be the second bandwidth.

And if the second bandwidth indication information and the ratio between the first bandwidth and the second bandwidth are included, determining the first bandwidth according to the second bandwidth and the ratio, and performing frequency domain truncation on the first data stream of the first bandwidth to enable the bandwidth of the second data stream to be the second bandwidth.

If the ratio between the first bandwidth and the second bandwidth is included, the first bandwidth or the second bandwidth may be predefined, and the frequency domain truncation is performed according to the predefined first bandwidth or second bandwidth and the ratio, so that the bandwidth of the second data stream is the second bandwidth.

If the first bandwidth indication information or the second bandwidth indication information is included, a ratio between the first bandwidth and the second bandwidth may be predefined, and frequency domain truncation is performed according to the first bandwidth or the second bandwidth and the ratio, so that the bandwidth of the second data stream is the second bandwidth.

In a possible implementation manner, the second processing indication information is used to indicate a filtering parameter, the filtering parameter includes a roll-off factor, and frequency-domain truncation is performed on the frequency-domain data according to the roll-off factor, so that the second bandwidth is smaller than the first bandwidth. The roll-off factor may not be indicated by the second processing indication information, e.g. predefined.

In a possible implementation manner, the method further includes receiving transmission resource indication information, where the transmission resource indication information is used to indicate time domain resources, and sending the transmission data stream on the time frequency resources. And transmitting the transmission data stream through the time domain resource indicated by the transmission resource indication information.

The transmission resource indication information, the first processing indication information and the second processing indication information may be carried in the same message, or the transmission resource indication information, the first processing indication information or the second processing indication information may be carried in the same message, or the three indication information may be carried in different messages respectively.

A second aspect of the embodiments of the present application provides a data transmission method, including:

performing inverse filtering processing on the third data stream to obtain a fourth data stream, wherein the bandwidth of the third data stream is a third bandwidth, the bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth;

and performing phase rotation removal and demodulation on the fourth data stream to obtain a bit stream.

Further, before the third data stream is subjected to inverse filtering processing, the transmission data stream is received and processed to obtain the third data stream. In the second aspect of the embodiment of the present application, in order to perform a process on received data by a receiving end, the receiving end may be a network device or a terminal device. The transmission data stream received by the receiving end has low PAPR, and is subjected to inverse filtering processing, phase rotation removal, demodulation and other processing, so that the bit stream sent by the sending end can be recovered.

In a possible implementation manner, before performing inverse filtering processing on the third data stream, third processing instruction information is received, and inverse filtering processing is performed on the third data stream according to the third processing instruction information. The third processing instruction information may be configured for the terminal device by the network device, and is used for informing the terminal device how to perform the filtering processing. In this manner, the sending end for transmitting the data stream is a network device, the receiving end for transmitting the data stream is a terminal device, and the process for receiving and processing data from the network device by the terminal device corresponds to a downlink transmission scenario.

In a possible implementation manner, the third processing indication information includes one or more of third bandwidth indication information, fourth bandwidth indication information, or a ratio between the third bandwidth and the fourth bandwidth, where the fourth bandwidth indication information is used to indicate the fourth bandwidth, and the third bandwidth indication information is used to indicate the third bandwidth and/or a center frequency point of the third bandwidth.

In a possible implementation manner, the third processing indication information is used to indicate a second filtering parameter, where the second filtering parameter includes a second roll-off factor, and the second roll-off factor may be the same as or different from the first roll-off factor.

In a possible implementation manner, the method further includes receiving fourth processing indication information, where the fourth processing indication information is used to indicate which modulation scheme is used for demodulation. And when receiving the fourth processing instruction information, the terminal device performs phase rotation removal and demodulation on the fourth data stream according to the fourth processing instruction information to recover the bit stream sent by the sending end.

The fourth processing indication information and the third processing indication information may be carried in the same message or may be carried in different messages.

The terminal device may demodulate according to the modulation method indicated by the fourth processing indication information, or demodulate according to a default modulation method, where the default modulation method may be agreed by a protocol.

In a possible implementation manner, the method further includes receiving transmission resource indication information, where the transmission resource indication information is used to indicate a time-frequency resource on which the transmission data stream is received. And indicating the time-frequency resource of the transmission data stream sent by the network equipment through the transmission resource indication information so that the terminal equipment can receive the transmission data stream on the time-frequency resource.

The transmission resource indication information, the third processing indication information and the fourth processing indication information may be carried in the same message, or the transmission resource indication information, the third processing indication information or the fourth processing indication information may be carried in the same message, or the three indication information may be carried in different messages respectively.

A third aspect of the embodiments of the present application provides a data transmission method, including:

modulating a bit stream to be sent to obtain a first data stream, wherein the first data stream comprises a plurality of first data, and the first data is a real number;

performing power expansion and phase rotation on the first data stream to obtain a second data stream, wherein the second data stream comprises a part of second data which is complex;

and processing the second data stream to obtain a transmission data stream, and sending the transmission data stream.

In the third aspect of the embodiment of the present application, the bit stream to be transmitted may be a bit stream of a pilot signal, and power expansion and phase rotation are performed on the pilot signal, so that the signal-to-noise ratio of the pilot signal can be improved, measurement estimation accuracy can be improved, and the PAPR of the pilot signal can be reduced.

In one possible implementation, performing power spreading and phase rotation on the first data stream to obtain a second data stream includes: performing power expansion on the first data stream to obtain a power expansion data stream, wherein the power expansion data stream comprises a plurality of power expansion data, and the power expansion data is a real number; and performing phase rotation on the power spreading data stream to obtain a second data stream.

In one possible implementation, performing power spreading and phase rotation on the first data stream to obtain a second data stream includes: performing phase rotation on the first data stream to obtain a phase rotation data stream, wherein the phase rotation data stream comprises a plurality of phase rotation data, and part of the phase rotation data included in the phase rotation data is complex; and performing power expansion on the phase rotation data stream to obtain a second data stream.

And the effect of performing power expansion or phase rotation first is the same.

A fourth aspect of the embodiments of the present application provides a data transmission apparatus, where the apparatus may be a terminal device, or an apparatus in the terminal device, for example, a chip, or an apparatus capable of being used in match with the terminal device. In one design, the apparatus may include a module corresponding to performing the method/operation/step/action described in the first aspect or the third aspect, and the apparatus may further include a module corresponding to performing the method/operation/step/action described in the second aspect, where the module may be a hardware circuit, a software circuit, or a combination of a hardware circuit and a software circuit. In one design, the apparatus may include a transceiver module and a processing module.

Illustratively, the processing module is configured to modulate and phase rotate a bit stream to obtain a first data stream; filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth; processing the second data stream to obtain a transmission data stream; and the transceiver module is used for transmitting the transmission data stream. The first data stream includes a plurality of first data, each of the first data carries n first bits, and n is a positive integer greater than 1.

Illustratively, the transceiver module is configured to receive a transmission data stream; the processing module is used for processing the transmission data stream to obtain a third data stream; performing inverse filtering processing on the third data stream to obtain a fourth data stream, where a bandwidth of the third data stream is a third bandwidth, a bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth; and performing phase rotation removal and demodulation on the fourth data stream to obtain a bit stream.

Exemplarily, the processing module is configured to modulate a bit stream to be sent to obtain a first data stream, where the first data stream includes a plurality of first data, and the first data is a real number; performing power expansion and phase rotation on the first data stream to obtain a second data stream, wherein the second data stream comprises a part of second data which is complex; processing the second data stream to obtain a transmission data stream; and the transceiver module is used for transmitting the transmission data stream.

The apparatus provided in the fourth aspect may also be a network device, or an apparatus in a network device, such as a chip, or an apparatus capable of being used in conjunction with a network.

A fifth aspect of the embodiments of the present application provides a data transmission apparatus, where the apparatus includes a processor, and is configured to implement the method described in the first aspect, the second aspect, or the third aspect. The apparatus may also include a memory to store instructions and data. The memory is coupled to the processor, and the processor, when executing the computer program or instructions stored in the memory, may cause the apparatus to perform the method described in the first, second or third aspect. The apparatus may also include a transceiver for the apparatus to communicate with other devices, such as a communication interface, circuit, bus, module, etc., and the other devices may be network devices, etc.

In one possible design, the apparatus includes: a memory for storing computer programs or instructions; the processor is used for modulating and phase rotating the bit stream to obtain a first data stream; filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth; processing the second data stream to obtain a transmission data stream; and the transceiver is used for transmitting the transmission data stream. The first data stream includes a plurality of first data, each of the first data carries n first bits, and n is a positive integer greater than 1.

In one possible design, the apparatus includes: a processor, a transceiver, and a memory. A memory for storing computer programs or instructions; a transceiver for receiving a transmission data stream; the processor is used for processing the transmission data stream to obtain a third data stream; performing inverse filtering processing on the third data stream to obtain a fourth data stream, where a bandwidth of the third data stream is a third bandwidth, a bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth; and performing phase rotation removal and demodulation on the fourth data stream to obtain a bit stream.

In one possible design, the apparatus includes: a processor, a transceiver, and a memory. A memory for storing computer programs or instructions; the device comprises a processor and a data processing module, wherein the processor is used for modulating a bit stream to be sent to obtain a first data stream, the first data stream comprises a plurality of first data, and the first data is a real number; performing power expansion and phase rotation on the first data stream to obtain a second data stream, wherein the second data stream comprises a part of second data which is complex; processing the second data stream to obtain a transmission data stream; and the transceiver is used for transmitting the transmission data stream.

In one possible design, the apparatus includes a processor and an interface, the processor being coupled with the memory through the interface, and when the processor executes the computer program or instructions in the memory, the apparatus is caused to perform the method provided in the first, second or third aspect. The apparatus provided by the fifth aspect may also be a network device, and the apparatus includes a transceiver for the apparatus to communicate with a terminal device.

A sixth aspect of embodiments of the present application provides a computer-readable storage medium, which includes instructions that, when executed on a computer, cause the computer to perform the method provided in the first, second, or third aspect.

A seventh aspect of embodiments of the present application provides a computer program product containing instructions that, when executed on a computer, cause the computer to perform the method provided in the first, second or third aspect.

An eighth aspect of the embodiments of the present application provides a chip, where the chip includes at least one processor and an interface, and is configured to call and execute a computer program stored in a memory, so that the method provided in the first aspect, the second aspect, or the third aspect is performed. Illustratively, the processor is configured to modulate and phase rotate a bit stream to obtain a first data stream; filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth; processing the transmission data stream to obtain a transmission data stream; and the interface is used for outputting the transmission data stream.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments of the present application will be described below.

Fig. 1 is a schematic diagram of a network architecture to which the embodiments of the present application are applied;

FIG. 2 is a schematic process flow diagram of DFTs-OFDM techniques;

FIG. 3 is a graph of BPSK versus π/2-BPSK;

FIG. 4a is a flow chart illustrating a method of transmitting data;

FIG. 4b is a diagram illustrating simulation results based on FIG. 4 a;

fig. 5 is a schematic flowchart of a data transmission method according to an embodiment of the present application;

FIG. 6 is a diagram of an exemplary modulation of π/2-4-PAM provided in an embodiment of the present application;

FIG. 7 is an exemplary diagram of frequency domain truncation and frequency domain expansion provided by an embodiment of the present application;

FIG. 8 is a diagram illustrating simulation results based on FIG. 7;

fig. 9 is a schematic diagram of a simulation result provided in the embodiment of the present application;

fig. 10 is a schematic flowchart of a data receiving method according to an embodiment of the present application;

FIG. 10a is a schematic diagram of an inverse filtering process provided in an embodiment of the present application;

fig. 11 is a schematic interaction flow diagram of uplink data transmission according to an embodiment of the present application;

fig. 12 is a schematic interaction flow diagram of downlink data transmission according to an embodiment of the present application;

fig. 13 is an exemplary constellation diagram of power spreading provided in an embodiment of the present application;

FIG. 14 is a schematic diagram of an apparatus according to an embodiment of the present disclosure;

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

fig. 16 is a schematic structural diagram of another apparatus provided in the embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. In the description of the embodiments of the present application, unless otherwise specified, "/" indicates a relationship in which the objects associated before and after are "or", for example, a/B may indicate a or B; in the present application, "and/or" is only an association relationship describing an associated object, and means that there may be three relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b and c can be single or multiple. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish technical features having substantially the same or similar functions. Those skilled in the art will appreciate that the terms "first," "second," etc. do not denote any order or quantity, nor do the terms "first," "second," etc. denote any order or importance.

The embodiment of the application can be applied to a Long Term Evolution (LTE) system; it can also be applied to the fifth generation (5)^th-genew, 5G) communication system, the 5G communication system may also be referred to as a New Radio (NR) system; but also to future communication systems, such as future networks or sixth generation communication systems, etc.

The embodiment of the application can be applied to a device to device (D2D) system, a machine to machine (M2M) system, a vehicle to electronics (V2X) system for communicating vehicles with anything, and the like.

The embodiment of the application can be applied to various scenes, such as a next-generation microwave scene, an NR-based microwave scene, or an Integrated Access Backhaul (IAB) scene.

Please refer to fig. 1, which is a schematic diagram of a network architecture to which the embodiments of the present application are applied. The network architecture may include one network device and one terminal device, the number and the form of the devices shown in fig. 1 are used for example and do not constitute a limitation to the embodiments of the present application, and two or more network devices and two or more terminal devices may be included in practical applications.

In this application, the network device may be any device having a wireless transceiving function. Including but not limited to: an evolved Node B (evolved Node B, NodeB or eNB or e-NodeB) in LTE, a base station (gnnodeb or gNB) or a transmission point (TRP) in NR, a base station of 3GPP subsequent evolution, an access Node in WiFi system, a wireless relay Node, a wireless backhaul Node, and the like. The base station may be: macro base stations, micro base stations, pico base stations, small stations, relay stations, or balloon stations, etc. Multiple base stations may support the same technology network as mentioned above, or different technologies networks as mentioned above. The base station may contain one or more co-sited or non co-sited TRPs. The network device may also be a radio controller, a Centralized Unit (CU), and/or a Distributed Unit (DU) in a Cloud Radio Access Network (CRAN) scenario. The network device may also be a server, a wearable device, or a vehicle mounted device, etc. The following description will take a network device as an example of a base station. The multiple network devices may be base stations of the same type or different types. The base station may communicate with the terminal, or may communicate with the terminal through the relay station. The terminal may communicate with multiple base stations of different technologies, for example, the terminal may communicate with a base station supporting an LTE network, may communicate with a base station supporting a 5G network, and may support dual connectivity with the base station of the LTE network and the base station of the 5G network.

The terminal equipment has a wireless transceiving function, can be deployed on land and comprises an indoor or outdoor, a handheld, a wearable or a vehicle-mounted terminal; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.). The terminal device may be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiving function, a Virtual Reality (VR) terminal device, an Augmented Reality (AR) terminal device, a wireless terminal in industrial control (industrial control), a vehicle-mounted terminal device, a wireless terminal in self driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), a wearable terminal device, and the like. The embodiments of the present application do not limit the application scenarios. A terminal may also be referred to as a terminal device, User Equipment (UE), access terminal device, in-vehicle terminal, industrial control terminal, UE unit, UE station, mobile station, remote terminal device, mobile device, UE terminal device, wireless communication device, UE agent, or UE apparatus, among others. The terminal equipment may also be fixed or mobile.

The embodiment of the application can be applied to a scene of data transmission between the network equipment and the terminal equipment, and can be a downlink transmission scene or an uplink transmission scene.

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 as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

The names or techniques referred to in the embodiments of the present application will be described below.

(1) Orthogonal frequency division multiplexing (DFTs-OFDM) for discrete Fourier transform spread spectrum

The DFTs-OFDM technology is one of uplink signal generation methods of Long Term Evolution (LTE). The DFTs-OFDM technique is preceded by an additional Discrete Fourier Transform (DFT) process before a conventional OFDM (orthogonal frequency division multiplexing) process, and thus may also be referred to as a linear precoding OFDM technique.

Referring to fig. 2, a process flow diagram of the DFTs-OFDM technique is shown. The sending end sequentially performs serial-to-parallel (serial-to-parallel) conversion, N-point DFT, subcarrier mapping, M-point Inverse Discrete Fourier Transform (IDFT), parallel-to-serial (parallel-to-serial) conversion, Cyclic Prefix (CP) and digital-to-analog converter (DAC) adding processing on a time-domain discrete sequence to obtain a transmission data stream, and then sends the transmission data stream to the receiving end through an antenna port and a channel (channel). When a receiving end receives the transmission data stream through a channel and an antenna port, analog-to-digital converter (ADC), cyclic prefix removal, serial-to-parallel (serial-to-parallel) conversion, M-point DFT, subcarrier mapping/equalization (equalization), N-point IDFT, and parallel-to-serial (parallel-to-serial) conversion are sequentially performed on the transmission data stream to obtain a time domain discrete sequence.

The sending end can obtain the frequency domain sequence of the time domain discrete sequence through the N-point DFT. And inputting IDFT after the frequency domain sequence subcarrier is mapped, and performing M-point IDFT, wherein N is less than M. Since the length of the IDFT is larger than that of the DFT, the part of the IDFT that is large is filled with zeros. After IDFT, adding a cyclic prefix may avoid symbol interference.

Because N < M and zero padding IDFT, the PAPR of the output transmission data stream is lower than that of the transmission data stream adopting OFDM technology, the power transmission efficiency of the terminal equipment can be improved, the service time of a battery can be prolonged, and the cost of the terminal equipment can be reduced.

(2) Frequency domain mapping (FDSS)

The peak-to-average ratio of the analog continuous signal output by a group of discrete time domain data signals after passing through the DAC has a certain relation with the correlation between the group of discrete time domain data. The set of discrete time-domain data signals may be the time-domain data signals with the cyclic prefix added in fig. 2, and the analog continuous signal output by the DAC may be the transmission data stream output by the DAC in fig. 2.

Assuming that a set of discrete time domain data signals y (n) is convolved with a set of time delay discrete data d (n), obtaining yd (n):

the peak-to-average ratios of the analog continuous signals output after the DAC are assumed to be PAPR 1 and PAPR 2 respectively. If d (n) is a set of designed weight coefficient sequences, the correlation between the adjacent data in yd (n) is better than that in y (n). So, PAPR 1 is smaller than PAPR 2. Therefore, after the set of discrete time domain data is convolved with the designed set of discrete data, the PAPR can be effectively reduced.

According to the convolution theorem, the convolution operation of two time-domain signals can be equivalent to a dot product operation of the two time-domain signals in the frequency domain. Therefore, a group of discrete time domain data is converted into discrete frequency domain data after being subjected to DFT, then a designed spectrum shaping (spectrum shaping) sequence is point-multiplied, and the time domain signal after being subjected to IDFT can effectively reduce the PAPR. This technique of PAPR reduction operates better in the frequency domain since the complexity of the dot product operation is lower than that of the convolution operation, and is therefore referred to as frequency domain shaping.

The PAPR of the 5G uplink signal can be further reduced if the FDSS technique is applied to DFTs-OFDM waveform processing of the 5G uplink. The basic idea is as follows: and performing point multiplication on the designed frequency spectrum forming sequence in frequency domain data after DFT and before Inverse Fast Fourier Transform (IFFT) in the DFTs-OFDM waveform processing process.

(3) Binary Phase Shift Keying (BPSK) modulation and pi/2-BPSK modulation

pi/2-BPSK modulation is an enhancement of BPSK modulation. In BPSK modulation, the phase difference between an input bit "1" and an input bit "0" is pi or-pi, i.e., the absolute value of the phase difference is pi. In pi/2-BPSK modulation, the phase difference between the kth modulation symbol and the kth-1 modulation symbol is pi/2 or-pi/2, i.e., the absolute value of the phase difference is pi/2. Illustratively, the first modulation symbol selects one of { +1, -1} based on the first input bit "1" or "0", e.g., the first input bit selects +1 for "1", and the second input bit selects-1 for "0"; the second modulation symbol selects one of { + j, -j } based on the second input bit, e.g., the second input bit is "1" select + j, the second input bit is "0" select-j; the third modulation symbol selects one of { +1, -1} based on the third input bit, the fourth modulation symbol selects one of { + j, -j } based on the fourth input bit, and so on. The kth modulation symbol is any one modulation symbol in the modulation symbol stream, and pi is a circumferential rate.

See FIG. 3 for a graph of BPSK versus π/2-BPSK. In BPSK modulation, there is a phase jump with an absolute value of pi in the phase difference during the transition of input bits "1" → "0" or "0" → "1", which results in an increase in the PAPR of the signal. In pi/2-BPSK modulation, the absolute value of the phase difference between two adjacent modulation symbols is pi/2, and pi is pi/2, so that the PAPR of the signal can be suppressed.

It is understood that the modulation symbol obtained by pi/2-BPSK modulation is obtained by performing phase rotation on the basis of the modulation symbol obtained by BPSK modulation, and the phase rotation factor is e^k×j×π/2，e^k×j×π/2K denotes an index of a modulation symbol, which may start from "0" ("k × pi/2"), "j × sin" ("k × pi/2"), "k" denotes an index of a modulation symbolNumbering, or may begin with a "1". For example, the index is numbered from "0", and the modulation symbols obtained by BPSK modulation include 1, -1,1,1, -1, 1; then the modulation symbols obtained with pi/2-BPSK modulation comprise 1, -j, -1, -j, -1, j.

(4) Pulse Amplitude Modulation (PAM)

PAM is a modulation scheme in which a series of analog signals are modulated with pulse signal samples, thereby truncating the amplitude of the original signal. This is a way of analog pulse modulation, in which the original signal is carried on a serial pulse carrier, the time interval between the carriers is fixed, and the magnitude of the value on the pulse carrier depends on the amplitude of the original signal. Demodulation of PAM detects the amplitude on each pulse carrier and recovers it.

As for the modulation result, a modulation result obtained by using BPSK may be equivalent to a modulation result obtained by using PAM having a modulation order of 2. Please refer to fig. 4a, which is a flowchart illustrating a data transmission method. The transmitting end modulates input information bits according to a BPSK modulation mode, performs pi/2 phase rotation on the modulated symbols, performs DFT on the phase-rotated symbols, performs IFFT on the symbols after DFT, adds cyclic prefix to the symbols after IFFT, and transmits data added with the cyclic prefix to the receiving end. After DFT is performed on the phase-rotated symbols, FDSS may be performed on the DFT symbols and then IFFT may be performed on the FDSS symbols, which may reduce PAPR.

The FDSS in fig. 4a generally uses a raised cosine roll-off filter for spectrum expansion, and the bandwidth occupied by the expanded symbol is 1+ α times of the original bandwidth, where α is a roll-off factor of the filter. For example, the original bandwidth is 10MHz, and after FDSS with α ═ 0.2 is performed, the occupied bandwidth is 12 MHz. The FDSS in fig. 4a may also use a root-raised cosine roll-off filter for spectrum expansion, etc. to implement spectrum expansion, and the specific filter used is not limited in the embodiment of the present application.

Please refer to fig. 4b, which is a diagram illustrating a simulation result based on fig. 4 a. In fig. 4b, the abscissa represents the PAPR of the transmission data, and the ordinate represents the Complementary Cumulative Distribution Function (CCDF) of the PAPR of the transmission data. As shown in fig. 4 b: curve I is CCDF of PAPR of sending data obtained by DFTs-OFDM + FDSS when the modulation mode of data is pi/2-BPSK modulation; curve II is CCDF of PAPR of the transmitted data obtained by DFTs-OFDM + FDSS when the modulation mode of the data is BPSK modulation; curve c is CCDF of PAPR of sending data obtained by DFTs-OFDM when the modulation mode of data is pi/2-BPSK modulation; and fourthly, when the modulation mode of the data is BPSK modulation, CCDF of PAPR of the transmitted data obtained by DFTs-OFDM is adopted.

From the simulation results shown in FIG. 4b, it can be seen that the PAPR using π/2-BPSK is lower than that of pure BPSK, the PAPR using FDSS is lower than that without FDSS, and the PAPR of π/2-BPSK + FDSS is the lowest and is close to 1, i.e. the peak power is almost equal to the average power.

In fig. 4a, by using a pi/2-BPSK modulation scheme, only 1 bit of information can be carried by one modulation symbol, which results in low spectrum efficiency. In addition, what is implemented by FDSS in fig. 4a is frequency domain spreading, so that the bandwidth finally occupied by the transmitted data is greater than the configured bandwidth.

In view of this, embodiments of the present application provide a data transmission method and apparatus, where PAPR of transmission data is reduced through frequency domain filtering, and the frequency domain filtering may enable a bandwidth finally occupied by the transmission data to be smaller than a configured bandwidth, so as to improve utilization rate of frequency domain resources. Meanwhile, in the embodiment of the application, the modulation data carries two or more bits, so that the spectrum efficiency can be improved.

The following describes a data transmission method provided in an embodiment of the present application.

Please refer to fig. 5, which is a flowchart illustrating a data transmission method according to an embodiment of the present application. The data transmission method shown in fig. 5 is executed by a sending end, where the sending end may be a network device in the network architecture shown in fig. 1, or may be a terminal device in the network architecture shown in fig. 1. The flow shown in fig. 5 may include, but is not limited to, the following steps:

step 101, modulating and phase rotating the first bit stream to obtain a first data stream.

The sending end modulates and phase rotates the first bit stream to obtain a first data stream.

The first data stream includes a plurality of first data, each of the first data carries n first bits, and n is a positive integer greater than 1.

The modulation method of the modulation may be PAM, and the modulation order may be 4, 8, 16, or more. PAM with a modulation order of 4 can be expressed as 4-PAM, 4PAM, PAM4, PAM-4, or the like. PAM with a modulation order of 8 can be expressed as 8-PAM, 8PAM, PAM8, PAM-8, or the like. The specific manner is not limited, and in the embodiments of the present application, N-PAM is taken as an example, and N is a modulation order.

The modulation order, which may be represented as 2, is related to the number n of first bits per first data bearerⁿThe superscript n is the number of first bits carried by each first data. For example, when the modulation order is 4, i.e., 4-PAM, each first data may carry 2 first bits, and the 2 bits may represent 4 discrete pulse amplitudes. For another example, when the modulation order is 8, i.e. 8-PAM, each first data may carry 3 first bits, and the 3 bits may represent 8 discrete pulse amplitudes.

Specifically, a sending end firstly modulates a first bit stream to obtain a first modulated data stream; and then, carrying out phase rotation on the first modulation data stream to obtain a first data stream.

The first bit stream may be an encoded bit stream, and includes a plurality of first bits, where the first bits may be bits "1" or bits "0", and the first bit stream is a group of bit streams consisting of bits "1" and bits "0", and the specific encoding method used for encoding is not limited in this embodiment of the application. Plural means two or more. The first bit stream can also be described as an input information bit stream, a bit stream to be transmitted, or a time-domain discrete sequence, etc.

The first modulated data stream includes a plurality of first modulated data, each of which is real, i.e., does not include an imaginary part. The first modulated data may also be described as first modulation symbols, each of which carries n first bits. For example, the modulation scheme is 4-PAM, and each first modulation symbol carries 2 first bits. The specific value of n is related to the modulation order.

And carrying out phase rotation on the first modulation data stream to obtain a first data stream. Specifically, each first modulation data is multiplied by a phase rotation factor to obtain a first data stream. Wherein the phase rotation factor can represent e^k×j×ωAnd ω may be pi/2 or pi/4, etc., and k denotes an index of the first modulation data, and the index may be numbered from "0" or may be numbered from "1". Specifically, assuming that the index is numbered from "0", and ω is π/2, the first modulation data and the phase rotation factor e are determined⁰Multiplying to obtain first data; second first modulation data and phase rotation factor e^1×j×π/2Multiplying to obtain second first data; third modulation data and phase rotation factor e^2×j×π/2And multiplying to obtain third first data, and repeating the steps to obtain the first data stream.

If ω is pi/2, the absolute value of the phase difference between two adjacent first modulation data can be made pi/2. When ω is π/2 and the modulation scheme is PAM, then modulation + phase rotation can be considered as the modulation scheme of π/2-4-PAM.

If ω is pi/4, the absolute value of the phase difference between two adjacent first modulation data can be made pi/4. When ω is pi/4 and the modulation scheme is PAM, modulation + phase rotation can be considered as the modulation scheme of pi/4-4-PAM.

Wherein, the first data stream comprises a part of the first data which is complex number. The partial first data may be odd-numbered first data in the first data stream, or even-numbered first data in the first data stream, depending on the numbering rule and the phase rotation factor of the first data stream.

Since the first data stream is modulated and phase-rotated, the first data stream may be considered as a modulated data stream, which comprises two parts, one part being real (comprising only real parts) and the other part being complex (comprising only imaginary parts, or comprising both real and imaginary parts).

For illustrative purposes, reference may be made to FIG. 6, which provides an example of the present applicationExemplary modulation of π/2-4-PAM. In fig. 6, the first bit stream includes 8 first bits of {0,1,1,0,0,0,1,1 }. In 4-PAM modulation, the amplitude of "00" is-3, the amplitude of "01" is-1, the amplitude of "11" is +1, and the amplitude of "10" is + 3. It should be noted that each amplitude in the 4-PAM modulation is an amplitude before normalization. And 4-PAM modulating the first bit stream to obtain first modulation data, wherein the first modulation data comprises { -1, +3, -3, +1}, and the first modulation data are all real numbers. The first modulated data is then phase rotated by a phase rotation factor e^k×j×π/2First modulation data-1 and phase rotation factor e⁰Multiplying to obtain first data-1; second first modulation data +3 and phase rotation factor e^1×j×π/2Multiplying cos (pi/2) + j × sin (pi/2) ═ j to obtain second first data +3 j; third first modulation data-3 and phase rotation factor e^2×j×π/2Multiplying cos (pi) + j × sin (pi) ═ 1 to obtain a third first data + 3; fourth first modulation data +1 and phase rotation factor e^3×j×π/2The fourth first data-j is obtained by multiplying cos (3 pi/2) + jxsin (3 pi/2) ═ j, and the first data shown in fig. 6 includes { -1, +3j, +3, -j }. It can be seen that the first and third data in the first data are real numbers, and the second and fourth data are two complex numbers. The first data includes { -1, +3j, +3, -j }, and is numbered from "0" based on the index of the first modulation data, and if the index of the first modulation data is numbered from "1", the first data includes { -j, -3, +3j, +1}, in which case, the first and third data in the first data are complex numbers, and the second and fourth data are real numbers.

In a possible implementation manner, if the sending end is a terminal device, the terminal device may modulate the first bit stream according to a modulation method indicated by the network device, or modulate and phase-rotate the first bit stream according to the modulation method indicated by the network device, which will be described in the embodiment shown in fig. 12.

In a possible implementation manner, if the sending end is a network device, the network device may notify the terminal device of a modulation method for modulating the first bit stream, or notify the terminal device of a modulation method for modulating and phase-rotating the first bit stream, which will be described in the embodiment shown in fig. 13.

And 102, filtering the first data stream to obtain a second data stream.

And the sending end carries out filtering processing on the first data stream to obtain a second data stream. The first data stream is time domain data, the bandwidth corresponding to the frequency domain is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth. The second bandwidth is smaller than the first bandwidth, and can be understood as the effect of frequency domain truncation or frequency domain reduction.

The filtering (shaping) process has an effect of making the second bandwidth smaller than the first bandwidth, and the filtering process may also be described as a shaping (shaping) process, that is, the shaping process may implement that the second bandwidth is smaller than the first bandwidth, and other technical names used for describing that the second bandwidth is smaller than the first bandwidth should fall within the protection scope of the embodiment of the present application.

In the embodiment of the application, the sending end performs filtering processing on the first data stream in the frequency domain. Specifically, the sending end performs DFT on the first data stream to obtain frequency domain data of the first data stream, and then performs filtering processing on the frequency domain data of the first data stream to obtain a second data stream, where the second data stream is the frequency domain data.

The filtering process may be implemented by an FDSS, which is different from the FDSS in fig. 4 a. The FDSS implements frequency domain truncation, while the FDSS in fig. 4a implements frequency domain extension. For example, the transmitting end is a terminal device, the transmission bandwidth configured for the terminal device by the network device is 10MHz, and after the filtering processing of the FDSS, the transmission bandwidth occupies 8MHz, and after the filtering processing according to the FDSS in fig. 4a, the transmission bandwidth occupies 12 MHz.

Compared with the filtering processing in the time domain, the filtering processing in the frequency domain has the advantages of small calculation amount and simple realization. Because the filtering process in the frequency domain is a multiplication and the filtering process in the time domain is a convolution. The filtering process in the time domain may include: and sequentially performing DFT and IFFT on the first data stream, and then convolving the filter function to obtain a second data stream, wherein the second data stream is time domain data. The time domain filtering processing can also realize frequency domain truncation, and has the defects of large calculation amount and more complex realization.

In a possible implementation manner, if the sending end is a terminal device, the terminal device may perform filtering processing on the first data stream according to an instruction of a network device, which will be described in the embodiment shown in fig. 12.

Illustratively, the network device instructs the terminal device to perform a filtering parameter of the filtering process, where the filtering parameter includes a roll-off factor, where the roll-off factor is used to describe a filter edge falling slope, and the roll-off factor may also be described as an extension factor, denoted by α, where α is smaller than 1, for example, 0.2. To ensure a low PAPR after the filtering process, α is not expected to be greater than 0.5. And the terminal equipment carries out filtering processing on the first data stream according to the indicated roll-off factor.

In a possible implementation manner, if the sending end is a network device, the network device may notify the terminal device of information related to the filtering process, which will be described in the embodiment shown in fig. 13.

Further, step 102 is followed by:

and 103, processing the second data stream to obtain a first transmission data stream.

And the sending end processes the second data to obtain a first transmission data stream. The process is used to transform the frequency domain data into time domain data. The processing may be time domain processing, which may include IFFT and cyclic prefix addition as shown in fig. 5. It should be noted that, the processing in step 103 in fig. 5 includes IFFT and cyclic prefix addition for example, and does not constitute a limitation to the embodiment of the present application, for example, in an actual scenario, digital-to-analog conversion may be further included after cyclic prefix addition, that is, the processing in step 103 may include IFFT, cyclic prefix addition, and digital-to-analog conversion. Further, each of the flows shown in fig. 5 is for example, and does not constitute a limitation to the embodiments of the present application, for example, in an actual scenario, subcarrier mapping may also be included before IFFT.

Step 104, sending the first transmission data stream.

The sending end sends the first transmission data stream to the receiving end. Accordingly, the receiving end receives the first transmission data stream from the transmitting end. The bandwidth corresponding to the first transmission data stream is the bandwidth corresponding to the second data stream, and is smaller than the bandwidth corresponding to the first data stream, so that frequency domain truncation is realized.

It can be understood that the bandwidth corresponding to the first transmission data stream is the bandwidth ultimately occupied by the first transmission data stream, and the bandwidth corresponding to the first data stream is the bandwidth occupied by the modulation data stream mapped to the frequency domain.

In the embodiment shown in fig. 5, the sending end implements frequency domain truncation through filtering processing, so that the bandwidth finally occupied by the first transmission data stream is smaller than the bandwidth mapped to the frequency domain by the modulation data stream, and the PAPR of the first transmission data stream can be reduced. Meanwhile, a modulation mode of high-order pi/2-PAM is adopted, so that one debugging symbol can bear n first bits, and the frequency spectrum efficiency is improved. The frequency domain truncation provided in the embodiment of the present application is also applicable to the case where n is 1, and the modulation scheme is pi/2-BPSK or pi/2-2 PAM, for example.

The effects of the embodiments of the present application are described below by two examples.

Example 1, the examples of the present application use pi/2-4-PAM to compare pi/2-4-PAM with 16-Quadrature Amplitude Modulation (QAM). In 16-QAM each modulation symbol carries 4 bits, in pi/2-4-PAM each modulation symbol carries 2 bits, it can be seen that 16-QAM carries twice as many bits per modulation symbol as pi/2-4-PAM. Therefore, under the condition that the bit number of the input bit stream is the same, the bandwidth occupied by the modulation symbols after being mapped to the frequency domain is twice that occupied by the modulation symbols in the range of pi/2-4-PAM compared with 16-QAM. In order to reduce PAPR, pi/2-4-PAM + FDSS performs frequency domain truncation, and 16-QAM + FDSS performs frequency domain expansion, so that the bandwidths finally occupied by the two are the same, which can be seen in table 1, where the bandwidth in table 1 is in units of Physical Resource Blocks (PRBs).

TABLE 1

Modulation system	Bandwidth of modulation symbol mapping to frequency domain	Frequency domain truncated/extended bandwidth
			π/2-4-PAM	100PRB	60PRB
16-QAM	50PRB	60PRB

In table 1, the roll-off factor α is 0.2. For 16-QAM + FDSS, 50PRB 1.2 ═ 60 PRB. A filter with a roll-off factor of 0.2 is employed for π/2-4-PAM + FDSS, resulting in 100PRB → 60 PRB. See fig. 7 for an exemplary plot of frequency domain truncation and frequency domain extension. In fig. 7, the bandwidth of the frequency domain data is the bandwidth mapped to the frequency domain by the modulation symbol, and the bandwidth of the output data is the bandwidth truncated/extended by the frequency domain. Fig. 8 is a schematic diagram of a simulation result based on fig. 7. In FIG. 8, the PAPR using π/2-4-PAM + FDSS is 0.6dB lower (10 dB) than that using 16-QAM + FDSS^-4). It can be seen that the effect of pi/2-4-PAM + frequency domain truncation is better than the effect of 16-QAM + frequency domain extension under the condition that the number of bits of the input bit stream is the same.

It can be understood that, under the condition that the same amount of data is transmitted by the transmitting end by adopting pi/2-4-PAM + frequency domain truncation and by adopting 16-QAM + frequency domain expansion, and the output data occupies the same bandwidth, the pi/2-4-PAM + frequency domain truncation has a better effect on suppressing the PAPR of the output data.

Example 2, the examples of this application use pi/2-BPSK, which is compared to Quadrature Phase Shift Keying (QPSK). In QPSK, each modulation symbol carries 2 bits, and the absolute value of the phase difference between two adjacent modulation symbols is pi/2; in pi/2-BPSK, each modulation symbol carries 1 bit, and it can be seen that QPSK carries twice as many bits as pi/2-BPSK per modulation symbol. Therefore, under the condition that the number of bits of the input bit stream is the same, the bandwidth occupied by the modulation symbols after mapping to the frequency domain is twice that of the QPSK, namely pi/2-BPSK. In order to reduce PAPR, pi/2-BPSK + FDSS performs frequency domain truncation, and QPSK + FDSS performs frequency domain expansion, so that the bandwidths occupied by the two are the same, which can be seen in table 2.

TABLE 2

Modulation system	Bandwidth of modulation symbol mapping to frequency domain	Frequency domain truncated/extended bandwidth
			π/2-BPSK	100PRB	60PRB
QPSK	50PRB	60PRB

In table 2, the roll-off factor α is 0.2. For QPSK + FDSS, 50PRB 1.2 ═ 60 PRB. A filter with a roll-off factor of 0.2 is employed for pi/2-BPSK + FDSS, resulting in 100PRB → 60 PRB. Fig. 9 is a schematic diagram of simulation results, which is based on table 2. In FIG. 9, the PAPR using π/2-BPSK + FDSS is 0.6dB (10) lower than that using QPSK + FDSS^-4). It can be seen that pi/2-BPSK + frequency domain truncation occurs with the same number of bits in the input bit streamThe effect of (2) is better than the QPSK + frequency domain spreading effect.

It can be understood that, under the condition that the transmitting end transmits the same amount of data by adopting pi/2-BPSK + frequency domain truncation and by adopting QPSK + frequency domain expansion, and the output data occupies the same bandwidth, the pi/2-BPSK + frequency domain truncation has a better PAPR suppression effect on the output data. By comparing the pi/2-BPSK + frequency domain truncation adopted in the embodiment of the application with the pi/2-BPSK + frequency domain extension shown in FIG. 4a, the better PAPR suppression effect of the output data by the pi/2-BPSK + frequency domain truncation can be obtained. Therefore, the frequency domain truncation can be used for processing the input bit stream by combining with high-order pi/2-PAM or pi/2-BPSK, so as to achieve the purpose of reducing the PAPR.

Fig. 5 shows a flow of a process of sending data by a sending end, and please refer to fig. 10, which is a schematic flow chart of a data receiving method provided in the embodiment of the present application, that is, a process of receiving data by a receiving end. It is understood that the process of receiving data by the receiving end is the reverse process of transmitting data by the transmitting end. The receiving end may be a network device in the network architecture shown in fig. 1, or may be a terminal device in the network architecture shown in fig. 1. The process illustrated in FIG. 10 may include, but is not limited to, the following steps:

step 201, receiving a second transmission data stream.

The receiving end receives a second transmission data stream from the transmitting end through the antenna port and the channel. The second transport stream may be the first transport stream or may be another transport stream. The second transmission data stream is time domain data.

Step 202, the second transmission data stream is processed to obtain a third data stream.

And the receiving end processes the second transmission data to obtain a third data stream, wherein the third data stream is frequency domain data. The process is used to transform time domain data into frequency domain data. This processing may include the de-cyclic prefix and DFT shown in fig. 10, and may also include the de-cyclic prefix and Fast Fourier Transform (FFT). It should be noted that the processing in step 202 in fig. 10 includes cyclic prefix removal and DFT for example, and does not constitute a limitation to the embodiment of the present application, for example, in an actual scenario, analog-to-digital conversion may be further included before cyclic prefix is added, that is, the processing in step 202 may include cyclic prefix removal, DFT, and analog-to-digital conversion.

Step 203, inverse filtering the third transmission data stream to obtain a fourth data stream.

And the receiving end carries out inverse filtering processing on the third transmission data stream to obtain a fourth data stream. The bandwidth corresponding to the fourth data stream is a fourth bandwidth, the bandwidth corresponding to the third data stream is a third bandwidth, and the third bandwidth is smaller than the fourth bandwidth.

The transmitting end adopts a high-order pi/2-PAM modulation mode to modulate to obtain a modulation symbol, which is equivalent to that after a time domain data sequence is transformed to a frequency domain through DFT, N/4 point shifting is carried out, and data points at the N/4 position of the frequency domain data sequence are taken as center conjugate symmetry. Wherein, N is the length of the time domain data sequence or the DFT transform length (i.e. N-point DFT), and the time domain data sequence is a time domain pure real data sequence, i.e. a time domain data sequence including only a real part. Therefore, the truncated data received by the receiving end contains all the original information. That is, the third data stream with the third bandwidth received by the receiving end includes all information of the data stream before the frequency domain truncation, so that the receiving end can recover the data sent by the sending end.

The inverse filtering process may include, but is not limited to, the following operations: the frequency domain data is shifted in the frequency domain, partial data is copied, and the conjugate of the copied data is obtained. See fig. 10a for a schematic diagram of the inverse filtering process. The frequency domain data after the truncation by the transmitting end is shown in the left side of fig. 10a, and the operations of shifting, copying partial data, and obtaining the conjugate of the copied data are performed to obtain the frequency domain data before the frequency domain truncation by the transmitting end, which is shown in the right side of fig. 10 a.

The effect of the inverse filtering process is that the fourth bandwidth can be made larger than the third bandwidth. The name inverse filtering process is used for example and does not constitute a limitation on the embodiments of the present application.

After the inverse filtering process, IDFT or IFFT process may be performed to obtain the fourth data stream as time domain data, so as to perform de-phase rotation and demodulation on the time domain data. Alternatively, the inverse filtering process includes IDFT or IFFT so that the fourth data stream is time domain data.

And step 204, performing phase rotation removal and demodulation on the fourth data stream to obtain a second bit stream.

And the receiving end firstly carries out phase rotation removal on the fourth data stream and then carries out demodulation to obtain a second bit stream. When phase rotation is performed, the phase rotation factor e is multiplied^k×j×ωThen the phase rotation factor e is multiplied when removing the phase rotation factor^-k×j×ωOr by a phase rotation factor e^k×j×ω。

The modulation method during demodulation is the same as the modulation method during modulation, for example, if the modulation debugging method is 4-PAM, the modulation method for demodulation is 4-PAM.

In the embodiment shown in fig. 10, the receiving end recovers the frequency domain data transmitted by the transmitting end through the inverse filtering process.

Fig. 5 illustrates a process in which a transmitting end transmits data, and fig. 10 illustrates a process in which a receiving end receives data. The following description is introduced from the perspective of interaction between a network device and a terminal device, and includes two processes of uplink data transmission and downlink data transmission.

Please refer to fig. 11, which is a schematic flow chart of uplink data transmission provided in the embodiment of the present application, and the schematic flow chart may include, but is not limited to, the following steps:

step 301, the network device sends first indication information to the terminal device. Accordingly, the terminal device receives the first indication information from the network device.

The first indication information is used to indicate how the terminal device processes the first bit stream, and the first bit stream may be understood as a bit stream to be transmitted by the terminal device, that is, a bit stream to be transmitted. The first indication information may include first processing indication information and/or second processing indication information.

The first processing indication information is used for indicating a first modulation mode, and the terminal device can perform modulation according to the first modulation mode. The first processing indication information has the following modes:

in a first aspect, the first processing instruction information is a current (MCS) index (index), that is, the first modulation scheme is instructed by the current MCS index. The current MCS index may indicate modulation schemes such as PAM, QAM, BPSK, QPSK, etc. and modulation orders, and then the first modulation scheme is + modulation orders such as PAM, QAM, BPSK, QPSK, etc. In this way, the terminal device may default to a phase rotation after modulation, e.g. a phase rotation of π/2.

In the second method, the first processing indication information is a newly defined MCS index, that is, the first modulation method is indicated by the newly defined MCS index. The newly defined MCS index can indicate pi/2 modulation modes such as pi/2-4-PAM, pi/2-BPSK, etc., and then the first modulation mode is pi/2-4-PAM, pi/2-BPSK, etc. In the method, the terminal equipment can perform modulation according to a modulation method such as 4-PAM, BPSK and the like, and then perform pi/2 phase rotation.

In a third mode, the first processing indication information is the current MCS index + additional indication information, the current MCS index may indicate modulation modes such as PAM, QAM, BPSK, QPSK, and the like, and a modulation order, and the additional indication information is used for indicating phase rotation, for example, indicating phase rotation of pi/2. In this way, the first modulation mode is a + modulation order such as PAM, QAM, BPSK, QPSK, or the like.

These three ways are for illustration and do not constitute a limitation to the embodiments of the present application.

The second processing instruction information is used for instructing the terminal device how to perform the filtering processing, and the terminal device may perform the filtering processing according to the second processing instruction information. The second processing indication information has the following modes:

in a first mode, the second processing indication information includes one or more of first bandwidth indication information, second bandwidth indication information, or a ratio between the first bandwidth and the second bandwidth. The first bandwidth indication information is used for indicating the first bandwidth, and the second bandwidth indication information is used for indicating the second bandwidth and/or the center frequency point of the second bandwidth.

The first bandwidth is an original data bandwidth, that is, a bandwidth occupied by the modulated and phase-rotated data, that is, a bandwidth corresponding to the first data stream. The second bandwidth is a bandwidth occupied by the output data, that is, a bandwidth occupied by the first transmission data stream, that is, a bandwidth corresponding to the second data stream.

In a second mode, the second processing indication information is used for indicating a first filtering parameter, and the first filtering parameter includes a first roll-off factor. Optionally, the first filtering parameter or the first indication information further includes a filter type, where the filter type indicates a function type of the filter, and the filter type may include, but is not limited to, a raised cosine function, a root raised cosine function, a kaiser window function, and other functions.

These two ways are for illustration and are not to be construed as limiting the embodiments of the present application.

When the first indication information includes the second processing indication information and does not include the first processing indication information, the terminal device may default to use a modulation method for modulation, and the modulation method is known to both the terminal device and the network device, for example, the protocol stipulates that the terminal device uses 4-PAM for modulation, and the network device uses 4-PAM for demodulation.

In a case where the first indication information includes the first processing indication information and does not include the second processing indication information, the terminal device may perform the filtering process according to a predefined parameter known to both the terminal device and the network device, for example, the predefined parameter is the roll-off factor α ═ 2, and then the terminal device performs the filtering process according to the roll-off factor α ═ 2, and the network device performs the inverse filtering process according to the roll-off factor α ═ 2.

It will be appreciated that where the first indication comprises a processing indication, the other processing indication may be default or predefined. Further, both the first processing indication information and the second processing indication information may be default or predefined. In this case, step 301 need not be performed.

Optionally, the first indication information further includes first transmission resource indication information, where the first transmission resource indication information is used to indicate a first time-frequency resource allocated by the network device for uplink transmission of the terminal device, so that the terminal device sends the first transmission resource to the network device on the first time-frequency resource. The first transmission resource indication information may indicate, in addition to the first time-frequency resource, a space domain resource, a code domain resource, and the like of uplink transmission.

In one possible implementation, step 301 may include: 301a, the network device sends first processing instruction information to the terminal device; 301b, the network device sends the second processing instruction information to the terminal device; 301c, the network device sends one or more of the first transmission resource indication information to the terminal device. If 301a and 301b are included, the first processing indication information and the second processing indication information may be carried in the same message or may be carried in different messages. If 301a, 301b, and 301c are included, the first transmission resource indication information and the first processing indication information may be carried in the same message, or may be carried in different messages; the first transmission resource indication information and the second processing indication information can be carried in the same message or different messages; the first transmission resource indication information, the first processing indication information and the second processing indication information may be carried in the same message, for example, the first indication information includes the first transmission resource indication information, the first processing indication information and the second processing indication information, or may be carried in three different messages.

Step 302, the terminal device processes the first bit stream according to the first indication information to obtain a first transmission data stream.

Under the condition that the network device executes the step 301, the terminal device performs modulation and phase rotation according to the first processing indication information to obtain a first data stream; filtering according to the second processing indication information to obtain a second data stream; and processing the second data stream to obtain a first transmission data stream. Step 302 is similar to the flow shown in fig. 5, except that the processing is performed in step 302 according to the processing instruction information.

The terminal device performs modulation and phase rotation according to the first processing indication information to obtain a first data stream, which may include:

for the first mode of processing the indication information, the terminal device modulates according to the first modulation mode to obtain a first modulation data stream, where first modulation data included in the first modulation data stream is a real number; and performing phase rotation on the first modulation data stream by default to obtain a first data stream.

And for the second mode of processing the first processing indication information, the terminal equipment carries out modulation and phase rotation according to the first modulation mode to obtain a first data stream.

And for the third mode of processing the first processing indication information, the terminal equipment modulates according to the first modulation mode to obtain a first modulation data stream, and performs phase rotation on the first modulation data stream according to the additional indication information to obtain a first data stream.

The terminal device performs filtering processing according to the second processing instruction information to obtain a second data stream, and may include:

for the first mode of processing the first indication information, if the second processing indication information includes the first bandwidth indication information and the second bandwidth indication information, the terminal device performs frequency domain truncation on the frequency domain data of the first data stream according to the first bandwidth and the second bandwidth, so that the bandwidth corresponding to the second data stream after the frequency domain truncation is the second bandwidth. If the second processing indication information includes the first bandwidth indication information and the ratio between the first bandwidth and the second bandwidth, the terminal device determines the second bandwidth according to the first bandwidth and the ratio, and then performs frequency domain truncation on the frequency domain data of the first data stream according to the second bandwidth, so that the bandwidth corresponding to the frequency domain truncated second data stream is the second bandwidth. If the second processing indication information includes the first bandwidth and a ratio between the first bandwidth and the second bandwidth, the terminal device determines the first bandwidth according to the second bandwidth and the ratio, and performs frequency domain truncation on the frequency domain data of the first data stream according to the first bandwidth and the second bandwidth, so that the bandwidth corresponding to the second data stream after the frequency domain truncation is the second bandwidth. If the second processing indication information includes the first bandwidth indication information, the terminal device may acquire the second bandwidth, and how to acquire the second bandwidth is not limited, and the second bandwidth may be indicated by other indication information; and performing frequency domain truncation on the frequency domain data of the first data stream according to the first bandwidth and the second bandwidth, so that the bandwidth corresponding to the second data stream after the frequency domain truncation is the second bandwidth. If the second processing indication information includes second bandwidth indication information, the terminal device may acquire the first bandwidth, and how to acquire the first bandwidth is not limited, and the first bandwidth may be indicated by other indication information; and performing frequency domain truncation on the frequency domain data of the first data stream according to the first bandwidth and the second bandwidth, so that the bandwidth corresponding to the second data stream after the frequency domain truncation is the second bandwidth. If the second processing instruction information includes the first bandwidth and a ratio between the first bandwidth and the second bandwidth, the terminal device acquires the first bandwidth or the second bandwidth, and how to acquire the first bandwidth or the second bandwidth is not limited specifically, determines the second bandwidth or the first bandwidth, and then performs frequency domain truncation on the frequency domain data of the first data stream, so that the bandwidth corresponding to the frequency domain truncated second data stream is the second bandwidth.

For the second mode of the first processing indication information, the terminal device directly performs frequency domain truncation on the frequency domain data of the first data stream according to the first roll-off factor, so that the second bandwidth is smaller than the first bandwidth. For example, the first roll-off factor is 0.2.

And in the case that the network device does not execute step 301, the terminal device performs modulation and phase rotation according to a default or predefined modulation mode, and performs filtering processing according to a default or predefined roll-off factor to obtain a second data stream.

Step 303, the terminal device sends the first transmission data stream to the network device. Accordingly, the network device receives the first transport stream from the terminal device.

Optionally, the first indication information further includes first transmission resource indication information, where the first transmission resource indication information is used to indicate a first time-frequency resource, and the terminal device sends the first transmission data stream to the network device on the first time-frequency resource.

Step 304, the network device processes the first transmission data stream to obtain a first bit stream.

When the network device receives the first transmission data stream, if the network device executes step 301, the network device processes the first transmission data stream according to the information indicated by the first indication information, so as to obtain a first bit stream. Step 304 is similar to the flow shown in fig. 10, except that processing is performed in step 304 based on the indicated information. For example, the network device performs demodulation according to the first modulation scheme, or performs de-phase rotation and demodulation according to the first modulation scheme.

If the network device does not perform step 301, the network device processes the first transmission data stream according to default or predefined information.

In the embodiment shown in fig. 12, the terminal device processes the first bit stream according to the first indication information sent by the network device, to obtain the first transmission data stream, and sends the first transmission data stream to the network device, where the first indication information may implement frequency domain truncation, so as to reduce a PAPR of the first transmission data stream.

Please refer to fig. 13, which is a schematic flow chart of downlink data transmission provided in the embodiment of the present application, and the schematic flow chart may include, but is not limited to, the following steps:

step 401, the network device processes the second bit stream to obtain a second transmission data stream.

The process of executing step 401 can refer to the data transmission process shown in fig. 10, and is not described herein again.

Step 402, the network device sends a second transmission data stream to the terminal device. Accordingly, the terminal device receives the second transmission data stream from the network device.

The network device sends the second transmission data stream to the terminal device through the antenna port and the channel.

In step 403, the network device sends the second indication information to the terminal device. Accordingly, the terminal device receives the second indication information from the network device.

The second indication information is used to indicate how the network device processes the second bitstream in step 401, so that the terminal device may perform the inverse operation when receiving the second transmission data stream to obtain the second bitstream. The second bit stream may be understood as a bit stream to be transmitted by the network device. The second indication information includes third processing indication information and/or fourth processing indication information.

The third processing instruction information is used for instructing the network device to perform a parameter of the filtering processing, so that the terminal device can perform inverse filtering processing according to the third processing instruction information. The third processing instruction information is similar to the second processing instruction information and is a parameter that instructs filtering processing, and the difference is that the second processing instruction information instructs the terminal device how to perform filtering processing on uplink transmission, and the third processing instruction information is used for instructing the network device of a parameter that has been performed or will be performed filtering processing on downlink transmission. The third processing indication information has the following modes:

in a first manner, the third processing indication information includes one or more of third bandwidth indication information, fourth bandwidth indication information, or a ratio between the third bandwidth and the fourth bandwidth. The third bandwidth indication information is used for indicating the third bandwidth, and the fourth bandwidth indication information is used for indicating the fourth bandwidth and/or the center frequency point of the fourth bandwidth.

The third bandwidth is an original data bandwidth, that is, a bandwidth occupied by the modulated and phase-rotated data, that is, a bandwidth corresponding to the third data stream. The fourth bandwidth is a bandwidth occupied by the output data, that is, a bandwidth occupied by the second transmission data stream, that is, a bandwidth corresponding to the second data stream, that is, a bandwidth configured by the network device for receiving the second transmission data stream for the terminal device.

In a second manner, the third processing indication information is used for indicating a second filtering parameter, and the second filtering parameter includes a second roll-off factor. Optionally, the second filtering parameter or the second indication information further includes a filter type, where the filter type indicates a function type of the filter, so that the terminal device selects a corresponding filter function to perform inverse filtering processing.

The fourth processing indication information is used to indicate a second modulation method for the network device to modulate the second bit stream, so that the terminal device demodulates according to the second modulation method. The second modulation mode may be the same as the first modulation mode, for example, both are 4-PAM; the first modulation scheme may be different, for example, 4-PAM and the second modulation scheme may be BPSK. The fourth processing indication information is similar to the first processing indication information, except that the first processing indication information is used for indicating which modulation method the terminal device adopts for modulation, and the fourth processing indication information is used for indicating the modulation method the network device already adopts or will adopt. The fourth processing indication information is the same as the first processing indication information, and there are three ways, which can be referred to in the detailed description of the first processing indication information.

Second indication information in the case where one kind of processing indication information is included and another kind of processing indication information is not included, the another kind of processing indication information may be default or predefined. Further, the third processing indication information and the fourth processing indication information may be default or predefined. In this case, step 403 need not be performed.

In the case where the network device executes step 403, step 403 may be executed after step 402 as shown in fig. 12, or may be executed before step 401.

Optionally, the second indication information further includes second transmission resource indication information, where the second transmission resource indication information is used to indicate a second time-frequency resource, and the second time-frequency resource is a time-frequency resource occupied by the network device sending the second transmission data stream, so that the terminal device can receive the second transmission data stream from the network device on the second time-frequency resource.

In one possible implementation, step 403 may include: 403a, the network device sends the third processing instruction information to the terminal device; 403b, the network device sends fourth processing instruction information to the terminal device; 403c, the network device sends one or more of the second transmission resource indication information to the terminal device. If 403a and 403b are included, the third processing indication information and the fourth processing indication information may be carried in the same message or may be carried in different messages. If the first transmission resource indication information and the third processing indication information include 403a, 403b, and 403c, the second transmission resource indication information and the third processing indication information may be carried in the same message or may be carried in different messages; the second transmission resource indication information and the fourth processing indication information may be carried in the same message or may be carried in different messages; the second transmission resource indication information, the third processing indication information and the fourth processing indication information may be carried in the same message, for example, the second indication information includes the second transmission resource indication information, the third processing indication information and the fourth processing indication information, and may also be carried in three different messages.

Step 404, the terminal device processes the second transmission data stream according to the second indication information to obtain a second bit stream.

And in the case that the network device executes step 403, the terminal device processes the second transmission data stream according to the second indication information to obtain a second bit stream. Step 404 is similar to the flow shown in fig. 10, except that the processing in step 404 is performed according to the second indication information.

And when the terminal equipment receives the second transmission data stream, sequentially performing cyclic prefix removal and DFT processing on the second transmission data stream to obtain a third data stream, wherein the third data stream is frequency domain data.

And the terminal equipment performs inverse filtering processing on the third data stream according to the third processing indication information to obtain a fourth data stream. If the third processing indication information is used for indicating a second filtering parameter, and the second filtering parameter includes a second roll-off factor, the terminal device performs operations such as copying, conjugate taking, moving and the like on the third data stream according to the second roll-off factor, so that the fourth bandwidth is greater than the third bandwidth. If the third processing indication information includes third bandwidth indication information and fourth bandwidth indication information, the terminal device performs operations such as copying, conjugating, moving and the like on the third data stream according to the third bandwidth and the fourth bandwidth, so that a bandwidth corresponding to the fourth data stream is the fourth bandwidth.

And the terminal equipment performs phase rotation removal and demodulation on the fourth data stream according to the fourth processing indication information to obtain a second bit stream. The dephasing twiddle factor may be a multiplication by a phase twiddle factor e^k×j×ωOr may be divided by the phase rotation factor e^k ^×j×ω. And a second modulation mode is adopted for demodulation during demodulation.

In the case that the network device executes step 403, the terminal device performs inverse filtering processing according to a default or predefined filtering parameter, and performs demodulation according to a default or predefined modulation mode to obtain a second bit stream.

In the embodiment shown in fig. 12, the network device informs the terminal device of the parameters of the second bitstream processing, so that the terminal device performs inverse processing according to the parameters to obtain the second bitstream. The network device can realize frequency domain truncation in the process of processing the second bit stream, thereby reducing the PAPR of the second transmission data stream.

In the embodiments shown in fig. 11 and 12, the default terminal device performs frequency-domain truncation when transmitting data, and the network device performs frequency-domain truncation when transmitting data. Optionally, the network device may indicate whether to perform frequency domain truncation or frequency domain extension.

For the uplink transmission shown in fig. 11, the network device may instruct the terminal device to perform frequency-domain truncation or frequency-domain expansion on the bit stream to be transmitted. The indication may be implicitly indicated by the second processing indication information, for example, implicitly indicated by a first roll-off factor, which indicates frequency domain expansion when the first roll-off factor is positive; and when the number is negative, frequency domain truncation is indicated. For another example, frequency domain truncation or frequency domain extension may be implicitly indicated by the size of the first bandwidth and the second bandwidth. The indication may also be indicated by additional indication information, for example, by an additional 1 bit, where the bit is 1, indicating frequency domain spreading; a 0 indicates frequency domain truncation. This facilitates a corresponding recovery of the network device when receiving the first transport stream.

For the downlink transmission shown in fig. 12, the network device may inform the terminal device whether the network device performs frequency-domain truncation or frequency-domain expansion on the bit stream to be transmitted. The indication may be implicitly indicated by the third processing or may be indicated by additional indication information. This facilitates a corresponding recovery of the terminal device upon reception of the second transmission data stream.

In order to improve the signal-to-noise ratio (SNR) of the pilot signal and improve the measurement estimation accuracy, power boosting (power boosting) of the pilot signal is required. The pilot signal may be a phase tracking reference signal (PT-RS) or other pilot reference signal. In the embodiment of the present application, the pilot signal is exemplified by PT-RS.

For example, see the power spreading example constellation shown in fig. 13, which is a constellation of 16-QAM. The PT-RS constellation points are located at four constellation points near the origin of coordinates before power expansion, and are located at a dotted square after power expansion, namely, the PT-RS constellation points are expanded from the inner periphery to the outermost periphery of the 16-QAM constellation diagram through power expansion.

In order to reduce the PAPR of a pilot signal, a transmitting end modulates a bit stream to be transmitted to obtain a first data stream, wherein the first data stream comprises a plurality of first data, and the first data is a real number; performing power expansion and phase rotation on the first data stream to obtain a second data stream, wherein the second data stream comprises a part of second data which is complex; and processing the second data stream to obtain a transmission data stream, and sending the transmission data stream. The bit stream to be transmitted is a bit stream of a pilot signal, for example, a bit stream of a PT-RS. Therefore, the signal-to-noise ratio of the pilot signal can be improved, the measurement estimation precision can be improved, and the PAPR of the pilot signal can be reduced.

The transmitting end modulates bit stream to be transmitted, and the modulation mode can be BPSK, 2-PAM or 4-PAM. Regardless of the modulation scheme of several orders used for the data, e.g., regardless of the modulation scheme of several orders used for the first bit stream or the second bit stream, the pilot signal is modulated in accordance with the modulation scheme of BPSK, 2-PAM, or 4-PAM. Which of BPSK, 2-PAM or 4-PAM is specifically used may be predefined, or may be related to the number of bits carried by the modulation symbols, i.e., the length of the pilot sequence. E.g. the length of the pilot sequence is 2, then modulation is performed with 4-PAM.

The sending end performs power spreading and phase rotation on the first data stream, which may be performing power spreading first and then performing phase rotation, or performing phase rotation first and then performing power spreading. Illustratively, assuming that a bit stream to be transmitted is { -1, +1, -1, +1} after modulation, power spreading is performed on { -1, +1, -1, +1} first, the spreading factor is a, and { -a, + a, -a, + a } is obtained; then, { -A, + A, -A, + A } is subjected to pi/2 phase rotation, and if the number is from 0, then { -A, + Aj, + A, -Aj } is obtained, and if the number is from 1, then { -Aj, -A, + Aj, + A } is obtained. Firstly, carrying out pi/2 phase rotation on { -1, +1, -1, +1} to obtain { -1, + j, +1, -j } if numbering is started from 0, and to obtain { -j, -1, + j, +1} if numbering is started from 1; then, the power expansion is carried out, the expansion multiple is A, and { -A, + Aj, + A, -Aj } or { -Aj, -A, + Aj, + A } is obtained. The power spreading factor may be predefined, or may be configured for the terminal device by the network device.

The sending end processes the second data stream, and the processing may be frequency domain-time domain processing, for example, DFT, IFFT, cyclic prefix adding, and the like are sequentially performed on the second data stream. FDSS may be included between DFT and IFFT, and may be frequency domain truncation or frequency domain spreading. How to process the second data stream is not limited in the embodiments of the present application.

Corresponding to the method provided by the above method embodiment, the embodiment of the present application further provides a corresponding apparatus, where the apparatus includes a module for executing the above embodiment. The module may be software, hardware, or a combination of software and hardware.

Fig. 14 shows a schematic of the structure of an apparatus. The apparatus 500 may be a network device, a terminal device, a chip system, a processor, or the like, which supports the network device to implement the method described above, or a chip, a chip system, a processor, or the like, which supports the terminal device to implement the method described above. The apparatus may be configured to implement the method described in the method embodiment, and refer to the description in the method embodiment.

The apparatus 500 may comprise one or more processors 501, where the processors 501 may also be referred to as processing units and may implement certain control functions. The processor 501 may be a general purpose processor or a special purpose processor, etc. For example, a baseband processor or a central processor. The baseband processor may be configured to process communication protocols and communication data, and the central processor may be configured to control a communication device (e.g., a base station, a baseband chip, a terminal chip, a DU or CU, etc.), execute a software program, and process data of the software program.

In an alternative design, the processor 501 may also store instructions and/or data 503, and the instructions and/or data 503 may be executed by the processor, so that the apparatus 500 performs the method described in the above method embodiment.

In an alternative design, processor 501 may include a transceiver unit to perform receive and transmit functions. The transceiving unit may be, for example, a transceiving circuit, or an interface circuit. The transmit and receive circuitry, interfaces or interface circuitry used to implement the receive and transmit functions may be separate or integrated. The transceiver circuit, the interface circuit or the interface circuit may be used for reading and writing code/data, or the transceiver circuit, the interface circuit or the interface circuit may be used for transmitting or transferring signals.

In yet another possible design, the apparatus 500 may include a circuit that may implement the functions of transmitting or receiving or communicating in the foregoing method embodiments.

Optionally, the apparatus 500 may include one or more memories 502, on which instructions 504 may be stored, and the instructions may be executed on the processor, so that the apparatus 500 performs the methods described in the above method embodiments. Optionally, the memory may further store data therein. Optionally, instructions and/or data may also be stored in the processor. The processor and the memory may be provided separately or may be integrated together. For example, the correspondence described in the above method embodiments may be stored in a memory, or stored in a processor.

Optionally, the apparatus 500 may further comprise a transceiver 505 and/or an antenna 506. The processor 501, which may be referred to as a processing unit, controls the apparatus 500. The transceiver 505 may be referred to as a transceiving unit, a transceiver, a transceiving circuit, or a transceiver, etc. for implementing transceiving function.

In one possible design, the apparatus 500 is a terminal device: processor 501 is configured to perform steps 101-103 in fig. 5; executing steps 202-204 in FIG. 10; step 302 in FIG. 11 is performed; step 404 in fig. 12 is performed. Transceiver 505 is configured to perform step 104 in fig. 5; step 201 in fig. 10 is performed; executing step 301 and step 303 in step 11; steps 402 and 403 in fig. 12 are performed.

In one possible design, the apparatus 500 is a network device: processor 501 is configured to perform steps 101-103 in fig. 5; executing steps 202-204 in FIG. 10; step 304 in FIG. 11 is performed; step 401 in fig. 12 is performed. Transceiver 505 is configured to perform step 104 in fig. 5; step 201 in fig. 10 is executed; executing step 301 and step 303 in step 11; step 402 and step 403 in fig. 12 are performed.

The processors and transceivers described herein may be implemented on Integrated Circuits (ICs), analog ICs, Radio Frequency Integrated Circuits (RFICs), mixed signal ICs, Application Specific Integrated Circuits (ASICs), Printed Circuit Boards (PCBs), electronic devices, and the like. The processor and transceiver may also be fabricated using various IC process technologies, such as Complementary Metal Oxide Semiconductor (CMOS), N-type metal oxide semiconductor (NMOS), P-type metal oxide semiconductor (PMOS), Bipolar Junction Transistor (BJT), Bipolar CMOS (bicmos), silicon germanium (SiGe), gallium arsenide (GaAs), and the like.

The apparatus in the description of the above embodiment may be a network device or a terminal device, but the scope of the apparatus described in the present application is not limited thereto, and the structure of the apparatus may not be limited by fig. 14. The apparatus may be a stand-alone device or may be part of a larger device. For example, the apparatus may be:

(1) a stand-alone integrated circuit IC, or chip, or system-on-chip or subsystem;

(2) a set of one or more ICs, which optionally may also include storage components for storing data and/or instructions;

(3) an ASIC, such as a modem (MSM);

(4) a module that may be embedded within other devices;

(5) receivers, terminals, smart terminals, cellular phones, wireless devices, handsets, mobile units, in-vehicle devices, network devices, cloud devices, artificial intelligence devices, and the like;

(6) others, and so forth.

Fig. 15 provides a schematic structural diagram of a terminal device. For convenience of explanation, fig. 15 shows only main components of the terminal device. As shown in fig. 15, the terminal apparatus 600 includes a processor, a memory, a control circuit, an antenna, and an input-output device. The processor is mainly used for processing communication protocols and communication data, controlling the whole terminal, executing software programs and processing data of the software programs. The memory is used primarily for storing software programs and data. The radio frequency circuit is mainly used for converting baseband signals and radio frequency signals and processing the radio frequency signals. The antenna is mainly used for receiving and transmitting radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are used primarily for receiving data input by a user and for outputting data to the user.

When the terminal device is started, the processor can read the software program in the storage unit, analyze and execute the instruction of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor performs baseband processing on the data to be sent and outputs baseband signals to the radio frequency circuit, and the radio frequency circuit processes the baseband signals to obtain radio frequency signals and sends the radio frequency signals outwards in the form of electromagnetic waves through the antenna. When data is transmitted to the terminal device, the radio frequency circuit receives a radio frequency signal through the antenna, the radio frequency signal is further converted into a baseband signal, the baseband signal is output to the processor, and the processor converts the baseband signal into the data and processes the data.

For ease of illustration, only one memory and processor are shown in FIG. 15. In an actual terminal device, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, and the like, which is not limited in this embodiment of the present invention.

As an alternative implementation manner, the processor may include a baseband processor and a central processing unit, where the baseband processor is mainly used to process a communication protocol and communication data, and the central processing unit is mainly used to control the whole terminal device, execute a software program, and process data of the software program. The processor in fig. 15 integrates the functions of the baseband processor and the central processing unit, and those skilled in the art will understand that the baseband processor and the central processing unit may also be independent processors, and are interconnected through a bus or the like. Those skilled in the art will appreciate that the terminal device may include a plurality of baseband processors to accommodate different network formats, the terminal device may include a plurality of central processors to enhance its processing capability, and various components of the terminal device may be connected by various buses. The baseband processor can also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit can also be expressed as a central processing circuit or a central processing chip. The function of processing the communication protocol and the communication data may be built in the processor, or may be stored in the storage unit in the form of a software program, and the processor executes the software program to realize the baseband processing function.

In one example, the antenna and the control circuit having the transceiving function may be regarded as the transceiving unit 611 of the terminal device 600, and the processor having the processing function may be regarded as the processing unit 612 of the terminal device 600. As shown in fig. 15, the terminal apparatus 600 includes a transceiving unit 611 and a processing unit 612. A transceiver unit may also be referred to as a transceiver, a transceiving device, etc. Optionally, a device for implementing the receiving function in the transceiving unit 611 may be regarded as a receiving unit, and a device for implementing the transmitting function in the transceiving unit 611 may be regarded as a transmitting unit, that is, the transceiving unit 611 includes a receiving unit and a transmitting unit. For example, the receiving unit may also be referred to as a receiver, a receiving circuit, etc., and the sending unit may be referred to as a transmitter, a transmitting circuit, etc. Optionally, the receiving unit and the sending unit may be integrated into one unit, or may be multiple units independent of each other. The receiving unit and the transmitting unit can be in one geographical position or can be dispersed in a plurality of geographical positions.

As shown in fig. 16, another apparatus 700 is provided in the present embodiment. The apparatus may be a terminal device or a component of a terminal device (e.g., an integrated circuit, a chip, etc.). The apparatus may also be a network device, and may also be a component of a network device (e.g., an integrated circuit, a chip, etc.). The apparatus may also be another communication module, which is used to implement the method in the embodiment of the method of the present application. The apparatus 700 may include a processing module 702 (processing unit). Optionally, a transceiver module 701 (transceiver unit) and a storage module 703 (storage unit) may also be included.

In one possible design, one or more of the modules in FIG. 16 may be implemented by one or more processors or by one or more processors and memory; or by one or more processors and transceivers; or by one or more processors, memories, and transceivers, which are not limited in this application. The processor, the memory and the transceiver can be arranged independently or integrated.

The apparatus has a function of implementing the terminal device described in the embodiment of the present application, for example, the apparatus includes a module or a unit or means (means) corresponding to the step of executing the terminal device described in the embodiment of the present application by the terminal device, and the function or the unit or the means (means) may be implemented by software or hardware, or may be implemented by hardware executing corresponding software, or may be implemented by a combination of software and hardware. Reference may be made in detail to the respective description of the corresponding method embodiments hereinbefore.

Or the apparatus has a function of implementing the network device described in the embodiment of the present application, for example, the apparatus includes a module or a unit or means (means) corresponding to the step of executing the network device described in the embodiment of the present application by the network device, and the function or the unit or the means (means) may be implemented by software or hardware, or may be implemented by hardware executing corresponding software, or may be implemented by a combination of software and hardware. Reference may be made in detail to the respective description of the corresponding method embodiments hereinbefore.

Optionally, each module in the apparatus 700 in the embodiment of the present application may be configured to perform the method described in fig. 5, fig. 10, fig. 11, or fig. 12 in the embodiment of the present application.

For the case where apparatus 700 is a terminal device:

in a possible implementation manner, the processing module 702 is configured to modulate and phase rotate a first bit stream to obtain a first data stream, where the first data stream includes a plurality of first data, each first data carries n first bits, and n is a positive integer greater than 1; filtering the first data stream to obtain a second data stream, wherein the bandwidth corresponding to the first data stream is a first bandwidth, the bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth; processing the second data stream to obtain a first transmission data stream; the transceiver module 701 is configured to send a first transmission data stream.

The transceiver module 701 is further configured to receive first indication information, where the first indication information includes first processing indication information; and the processing module is specifically configured to modulate and phase rotate the first bit stream according to the first processing indication information.

In a possible implementation manner, the transceiver module 701 is configured to receive a second transmission data stream; a processing module 702, configured to process the second transmission data stream to obtain a third data stream; performing inverse filtering processing on the third data stream to obtain a fourth data stream, where a bandwidth of the third data stream is a third bandwidth, a bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth; and performing phase rotation removal and demodulation on the fourth data stream to obtain a second bit stream.

The transceiver module 701 is further configured to receive second indication information, where the second indication information includes third processing indication information; and the processing module is specifically configured to perform inverse filtering processing on the third data stream according to the third processing instruction information.

In a possible implementation manner, the processing module 702 is configured to modulate a bit stream to be sent to obtain a first data stream, where the first data stream includes a plurality of first data, and the first data is a real number; performing power expansion and phase rotation on the first data stream to obtain a second data stream, wherein the second data stream comprises a part of second data which is complex; processing the second data stream to obtain a transmission data stream; the transceiver module 701 is configured to send a transmission data stream.

For the case where the apparatus 700 is a network device:

Those skilled in the art will also appreciate that the various illustrative logical blocks and steps (step) set forth in the embodiments of the present application may be implemented in electronic hardware, computer software, or combinations of both. Whether such functionality is implemented as hardware or software depends upon the particular application and design requirements of the overall system. 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 embodiments of the present application.

The techniques described herein may be implemented by various means. For example, these techniques may be implemented in hardware, software, or a combination of hardware and software. For a hardware implementation, the processing units used to perform these techniques at a communication device (e.g., a base station, a terminal, a network entity, or a chip) may be implemented in one or more general-purpose processors, Digital Signal Processors (DSPs), digital signal processing devices, Application Specific Integrated Circuits (ASICs), programmable logic devices, Field Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

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 EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, Synchronous Link DRAM (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.

The present application also provides a computer-readable medium having stored thereon a computer program which, when executed by a computer, performs the functions of any of the method embodiments described above.

The present application also provides a computer program product which, when executed by a computer, implements the functionality of any of the above-described method embodiments.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, 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., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disk (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

Those of ordinary skill in the art will understand that: the various numbers of the first, second, etc. mentioned in this application are only used for the convenience of description and are not used to limit the scope of the embodiments of this application, but also to indicate the sequence.

The correspondence shown in the tables in the present application may be configured or predefined. The values of the information in each table are only examples, and may be configured to other values, which is not limited in the present application. When the correspondence between the information and each parameter is configured, it is not always necessary to configure all the correspondences indicated in each table. For example, in the table in the present application, the correspondence shown in some rows may not be configured. For another example, appropriate modification adjustments, such as splitting, merging, etc., can be made based on the above tables. The names of the parameters in the tables may be other names understandable by the communication device, and the values or the expression of the parameters may be other values or expressions understandable by the communication device. When the above tables are implemented, other data structures may be used, for example, arrays, queues, containers, stacks, linear tables, pointers, linked lists, trees, graphs, structures, classes, heaps, hash tables, or hash tables may be used.

Predefinition in this application may be understood as defining, predefining, storing, pre-negotiating, pre-configuring, curing, or pre-firing.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

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

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of data transmission, comprising:

modulating and phase rotating a bit stream to obtain a first data stream;

filtering the first data stream to obtain a second data stream, where a bandwidth corresponding to the first data stream is a first bandwidth, a bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth;

2. The method of claim 1, wherein the first data stream comprises a plurality of first data, each first data carrying n bits, n being a positive integer greater than 1.

3. The method of claim 1,

modulating and phase rotating the bit stream to obtain a first data stream, including:

modulating a bit stream by adopting a modulation mode to obtain a modulated data stream, wherein the modulated data stream comprises a plurality of modulated data, and the modulated data is a real number;

and performing phase rotation on the modulation data stream to obtain a first data stream, wherein the first data stream comprises a part of complex numbers of first data.

4. The method of claim 1, further comprising:

and receiving first processing indication information, wherein the first processing indication information is used for indicating a modulation mode for modulating the bit stream.

5. The method according to any one of claims 1-4, further comprising:

and receiving second processing indication information, wherein the second processing indication information is used for indicating parameters for filtering the first data stream.

6. The method of claim 5, wherein the second processing indication information comprises one or more of first bandwidth indication information, second bandwidth indication information, or a ratio between the first bandwidth and the second bandwidth;

the first bandwidth indication information is used for indicating the first bandwidth, and the second bandwidth indication information is used for indicating the second bandwidth and/or a center frequency point of the second bandwidth.

7. The method of claim 5, wherein the second processing indication information is used for indicating a filtering parameter, and wherein the filtering parameter comprises a roll-off factor.

8. The method according to any one of claims 1-4, further comprising:

receiving transmission resource indication information, wherein the transmission resource indication information is used for indicating time frequency resources;

the sending the transmission data stream includes:

and transmitting the transmission data stream on the time-frequency resource.

9. A method of data transmission, comprising:

receiving a transmission data stream, and processing the transmission data stream to obtain a third data stream;

performing inverse filtering processing on the third data stream to obtain a fourth data stream, where a bandwidth of the third data stream is a third bandwidth, a bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth;

10. The method of claim 9, further comprising:

and receiving third processing indication information, wherein the third processing indication information is used for indicating a parameter for performing inverse filtering processing on the third data stream.

11. The method of claim 10, wherein the third processing indication information comprises one or more of third bandwidth indication information, fourth bandwidth indication information, or a ratio between the third bandwidth and the fourth bandwidth;

the fourth bandwidth indication information is used to indicate the fourth bandwidth, and the third bandwidth indication information is used to indicate the third bandwidth and/or a center frequency point of the third bandwidth.

12. The method of claim 10, wherein the third processing indication information is used for indicating a filtering parameter, and wherein the filtering parameter comprises a roll-off factor.

13. The method according to claim 9 or 10, characterized in that the method further comprises:

and receiving fourth processing indication information, wherein the fourth processing indication information is used for indicating a modulation mode for demodulating the fourth data stream.

14. The method according to claim 9 or 10, characterized in that the method further comprises:

the receiving the transmission data stream includes:

and receiving the transmission data stream on the time-frequency resource.

15. A data transmission apparatus, comprising:

the processing module is used for modulating and rotating the phase of the bit stream to obtain a first data stream; filtering the first data stream to obtain a second data stream, where a bandwidth corresponding to the first data stream is a first bandwidth, a bandwidth corresponding to the second data stream is a second bandwidth, and the second bandwidth is smaller than the first bandwidth;

the processing module is further configured to process the second data stream to obtain a transmission data stream;

and the transceiver module is used for transmitting the transmission data stream.

16. The apparatus of claim 15, wherein the first data stream comprises a plurality of first data, each first data carrying n bits, n being a positive integer greater than 1.

17. The apparatus of claim 15, wherein the processing module is specifically configured to: modulating a bit stream by adopting a modulation mode to obtain a modulated data stream, wherein the modulated data stream comprises a plurality of modulated data, and the modulated data is a real number;

18. The apparatus of claim 15, wherein the transceiver module is further configured to receive first processing indication information, and wherein the first processing indication information is used to indicate a modulation scheme for modulating the bit stream.

19. The apparatus according to any of claims 15-18, wherein the transceiver module is further configured to receive second processing indication information, and the second processing indication information is used to indicate a parameter for performing filtering processing on the first data stream.

20. The apparatus of claim 19, wherein the second processing indication information comprises one or more of first bandwidth indication information, second bandwidth indication information, or a ratio between the first bandwidth and the second bandwidth;

21. The apparatus of claim 19, wherein the second processing indication information is used for indicating a filtering parameter, and wherein the filtering parameter comprises a roll-off factor.

22. The apparatus according to any one of claims 15 to 18,

the transceiver module is further configured to receive transmission resource indication information, where the transmission resource indication information is used to indicate time-frequency resources;

and the transceiver module is specifically configured to send the transmission data stream on the time-frequency resource.

23. A data transmission apparatus, comprising:

the receiving and transmitting module is used for receiving the transmission data stream;

a processing module, configured to process the transmission data stream to obtain a third data stream, and perform inverse filtering on the third data stream to obtain a fourth data stream, where a bandwidth of the third data stream is a third bandwidth, a bandwidth of the fourth data stream is a fourth bandwidth, and the third bandwidth is smaller than the fourth bandwidth; and performing phase rotation removal and demodulation on the fourth data stream to obtain a bit stream.

24. The apparatus of claim 23, wherein the transceiver module is further configured to receive third processing indication information, and wherein the third processing indication information is used to indicate a parameter for performing inverse filtering processing on the third data stream.

25. The apparatus of claim 24, wherein the third processing indication information comprises one or more of third bandwidth indication information, fourth bandwidth indication information, or a ratio between the third bandwidth and the fourth bandwidth;

26. The apparatus of claim 24, wherein the third processing indication information is used for indicating a filtering parameter, and wherein the filtering parameter comprises a roll-off factor.

27. The apparatus according to claim 23 or 24, wherein the transceiver module is further configured to receive fourth processing indication information, and the fourth processing indication information is used to indicate a modulation scheme for demodulating the fourth data stream.

28. The apparatus according to claim 23 or 24, wherein the transceiver module is further configured to receive transmission resource indication information, the transmission resource indication information indicating time-frequency resources;

the transceiver module is specifically configured to receive the transmission data stream on the time-frequency resource.

29. A data transmission apparatus, characterized in that the apparatus comprises a processor, a transceiver and a memory, which when executing a computer program or instructions in the memory causes the data transmission apparatus to perform the method of any of claims 1-8.

30. A data transmission apparatus, characterized in that the apparatus comprises a processor, a transceiver and a memory, which when executing a computer program or instructions in the memory causes the data transmission apparatus to perform the method of any of claims 9-14.

31. A chip comprising a processor and an interface; the processor is configured to retrieve from the memory and execute a computer program stored in the memory, such that the method of any of claims 1-8 or 9-14 is performed.

32. A computer-readable storage medium comprising instructions that, when executed on a computer, cause the computer to perform the method of any of claims 1-8 or 9-14.