WO2021134608A1

WO2021134608A1 - Signal transmission method and apparatus

Info

Publication number: WO2021134608A1
Application number: PCT/CN2019/130801
Authority: WO
Inventors: 贾琼; 张菁菁; 尤肖虎
Original assignee: 华为技术有限公司
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2021-07-08

Abstract

A signal transmission method and apparatus, capable of improving energy efficiency of a system, thereby reducing power consumption of the system. The signal transmission method comprises: a transmitting end determines an information bit to be transmitted; the transmitting terminal performs chirp spread spectrum modulation on said information bit to obtain a modulation signal; the transmitting end performs phase compensation on the modulated signal to obtain a signal to be transmitted, phases of said signal on two adjacent symbols being continuous; the transmitting end transmits said signal.

Description

Signal transmission method and device

Technical field

This application relates to the field of communications, and more specifically, to a signal transmission method and device.

Background technique

Long range (LoRa) technology is a kind of low power wide area network (LPWAN) communication technology, and is an ultra-long-distance wireless transmission based on spread spectrum technology adopted and promoted by Semtech in the United States. Program. This solution changes the previous compromise between transmission distance and power consumption, and provides users with a simple system that can achieve long-distance, long battery life, and high-capacity, and expand the sensor network. LoRa technology has the characteristics of long distance, low power consumption (long battery life), wide coverage, and low cost.

There are four main current spread spectrum technologies: direct sequence spread spectrum, frequency hopping spread spectrum, time hopping spread spectrum and chirp. Chirp spread spectrum belongs to linear frequency modulation. Chirp spread spectrum means that within a symbol period, the carrier frequency of the system linearly "sweeps" a frequency range, and then a large broadband sweep signal is formed. Chirp spread spectrum has the advantages of low power consumption, long distance, low complexity and strong anti-interference ability, and has been widely used in the communication field. For example, chirp spread spectrum can be used as a key technology of the physical layer of LoRa communication.

The current chirp spread spectrum-based scheme uses a combination of chirp spread spectrum modulation and Hamming coding, and the energy efficiency of the system is low.

Summary of the invention

The present application provides a signal transmission method and device, which can improve the energy efficiency of the system, thereby reducing the power consumption of the system.

In a first aspect, a signal transmission method is provided, including: a sending end determines information bits to be sent; the sending end performs chirp spread spectrum modulation on the information bits to be sent to obtain a modulated signal; The modulation signal is phase-compensated to obtain a signal to be sent, and the phases of two adjacent symbols in the signal to be sent are continuous; the sending end sends the signal to be sent.

The signal transmission method of the embodiment of the present application performs phase compensation on the modulated signal obtained after chirp spread spectrum modulation by the transmitting end, so that the phase of the signal to be transmitted obtained after phase compensation is continuous on two adjacent symbols, which effectively reduces The PAPR of the signal to be sent improves the energy efficiency of the system, thereby reducing system power consumption.

It should be understood that the above "the phase of the signal to be transmitted on two adjacent symbols is continuous" refers to: the end phase of the signal to be transmitted on the mth symbol and the start phase of the signal to be transmitted on the m+1th symbol Equal, m is a positive integer. In addition, the above-mentioned phase compensation may mean that the transmitting end respectively multiplies the modulated signal on one or more symbols by a specific phase, so that the end phase and the start phase of the signal on adjacent symbols in the one or more symbols are equal.

With reference to the first aspect, in some implementations of the first aspect, in the modulated signal, the initial phase and the end phase of the modulated signal on the first symbol are

Where i represents the cyclic shift value of the modulated signal on the first symbol based on the base signal of the chirp spread spectrum signal, B represents the frequency sweep range, T represents the length of the first symbol, and i is an integer greater than 0, B and T are both greater than 0; the transmitting end performs phase compensation on the modulated signal, including: the transmitting end multiplies the modulated signal on the first symbol by

Obtain the signal to be sent on the first symbol.

In the embodiment of the present application, the transmitting end may multiply the modulation signal on one or more symbols by the reverse phase of the modulation signal, so that the start phase and the end phase of the modulation signal on the one or more symbols are both 0, in this way, the phase continuity of the modulation signal of two adjacent symbols can be realized.

The phase compensation method of the embodiment of the present application is easy to implement, and can make the phase of the signal to be transmitted obtained after phase compensation continuous on two adjacent symbols, which effectively reduces the PAPR of the signal to be transmitted, improves the energy efficiency of the system, and reduces System power consumption.

With reference to the first aspect, in some implementations of the first aspect, before the transmitting end performs spread spectrum modulation on the information bits to be sent, the method further includes: Bits are encoded by convolutional codes to obtain coded bits; the sending end performs chirp spread spectrum modulation on the information bits to be sent, including: the sending end performs chirp spread spectrum modulation on the coded bits to obtain the modulation symbols .

The embodiment of the application combines convolutional code encoding and chirp spread spectrum modulation, and performs phase compensation on the modulated signal, so that the phase of the signal to be transmitted obtained after phase compensation is continuous on two adjacent symbols, which effectively reduces The PAPR of the signal to be sent and the large coding gain of the convolutional code can improve the detection performance of the receiving end, that is, the receiving end can achieve correct demodulation in a lower signal-to-noise ratio environment, which is equivalent to the receiving end achieving the same detection performance The power required at the time is lower. Therefore, the embodiments of the present application can improve the energy efficiency of the system, thereby reducing the power consumption of the system.

Optionally, the aforementioned convolutional code can also be replaced with a low density parity check (LDPC) code, a turbo code, and the like.

In a second aspect, another signal transmission method is provided, which includes: a sending end determines information bits to be sent; the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent to obtain a modulated signal; The sending end sends the modulated signal.

In the signal transmission method of the embodiment of the present application, the transmitting end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, so that the modulated signal can carry more information, which improves the energy efficiency and spectrum efficiency of the system, thereby reducing system power consumption.

It should be understood that the above-mentioned chirp spread modulation and phase modulation belong to the modulation process of the information bits to be sent by the sending end. The sending end can perform chirp spread modulation and then phase modulation on the information bits to be sent, or it can also perform the information bits to be sent first. Phase modulation is followed by chirp spread spectrum modulation. The embodiment of the present application does not limit the sequence of modulation.

Optionally, the above-mentioned phase modulation may be quadrature phase shift keying (QPSK), phase shift keying (PSK), or quadrature amplitude modulation (QAM), for example,

QPSK, 8PSK, 16QAM, etc., but the embodiment of the present application does not limit this.

With reference to the second aspect, in some implementation manners of the second aspect, the transmitting end performing spread-spectrum modulation and phase modulation on the information bits to be sent includes: the transmitting end spreading the information bits to be sent Frequency modulation to obtain a primary modulation signal; the transmitting end performs phase modulation on the primary modulation signal to obtain the modulation signal.

In the embodiment of the present application, the transmitting end performs chirp spread spectrum modulation on the information bits to be sent first, and then performs phase modulation, so that the modulated signal can carry more information, which improves the energy efficiency and spectrum efficiency of the system, thereby reducing system power consumption.

With reference to the second aspect, in some implementations of the second aspect, in the modulated signal, the modulated signal on the first symbol is (s ⁱ )′=s ⁱ ×e ^φ ; where s ⁱ represents the The first-level modulation signal on the first symbol, i represents the cyclic shift value of the first-level modulation signal on the first symbol based on the base signal of the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

Taking the first symbol as an example, assuming that the modulation signal on the first symbol is cyclically shifted by i during the first-level modulation process, the corresponding first-level modulation signal can be expressed as s ⁱ , and then the sending end can The modulation symbol is subjected to secondary modulation (ie phase modulation), that is, s ^{i is} multiplied by e ^φ to obtain the modulated signal (s ⁱ )'. Among them, φ represents the phase of the phase modulation, for example, when the phase modulation mode is

In QPSK,

or

When the phase modulation method is

In QPSK,

With reference to the second aspect, in some implementations of the second aspect, before the transmitting end performs spread-spectrum modulation and phase modulation on the information bits to be transmitted, the method further includes: the transmitting end performs The information bits to be sent are encoded by convolutional codes to obtain coded bits; the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, including: the sending end performs chirp spread spectrum modulation on the coded bits And phase modulation to obtain the modulation symbol.

The embodiment of the application combines convolutional code encoding, chirp spread spectrum modulation, and phase modulation. Because the coding gain of the convolutional code is large, the modulated signal can carry more information, which improves the energy efficiency and spectrum efficiency of the system, thereby reducing the system Power consumption.

In a third aspect, another signal transmission method is provided, including: a receiving end receives a modulated signal, the modulated signal is generated by chirp spreading modulation on coded bits obtained through convolutional code encoding; The modulated signal is demodulated to obtain soft information; the receiving end performs convolutional decoding based on the soft information to obtain information bits.

In the embodiment of this application, the transmitting end performs convolutional code encoding and chirp spread spectrum modulation on the information bits to be sent, and transmits the obtained modulation symbols. The receiving end can obtain soft information based on the received modulation symbols, thereby performing convolutional translation based on the soft information. code. Since the coding gain of the convolutional code is large, and the receiving end performs convolutional decoding based on soft information, the gain is further improved. Therefore, the signal transmission method of the embodiment of the present application can achieve a lower bit signal-to-noise ratio environment. The same spectrum efficiency, in other words, can achieve higher spectrum efficiency under the same bit signal-to-noise ratio environment, thereby improving the energy efficiency of the system and reducing the power consumption of the system.

In a possible implementation, the receiving end performs convolutional decoding on the soft information obtained by demodulation, which can be applied to the scenario of uplink transmission. Because the network equipment has strong computing power, this soft decoding method is used. Ways can improve the energy efficiency of the system. For downlink transmission, terminal devices (such as IoT devices) are not very capable of computing, and hard decoding can also be used, while taking into account energy efficiency and complexity, thereby improving system performance.

With reference to the third aspect, in some implementation manners of the third aspect, the soft information is determined based on non-coherent demodulation and log-likelihood ratio LLR.

With reference to the third aspect, in some implementation manners of the third aspect, for the value b _{k of} the k-th bit, the soft information satisfies the following formula:

Among them, k∈[1,2,…,log ₂ M], i∈{0,…,M-1},

Indicates the set of symbols whose value is χ of the k-th information bit, χ is valued as 0 or 1, and s ⁱ represents the modulated signal on symbol i,

Indicates that the symbol corresponding to ^{s i belongs to the set}

I ₀ is the Bessel function, σ ² is the energy of the noise,

γ _i =<s ^j e ^jφ +n, s ⁱ >, i represents the cyclic shift value of the base signal of the chirp spreading signal based on the first symbol, and s ^j represents the modulation corresponding to the symbol sent by the receiving end assuming that the sending end Signal, M=B×T, B represents the frequency sweep range, T represents the length of the symbol i, i is an integer greater than 0, and both B and T are greater than 0.

With reference to the third aspect, in some implementations of the third aspect, the modulation symbol has also undergone phase modulation, and the modulation signal corresponding to the symbol i is (s ⁱ )′=s ⁱ ×e ^φ ; where s ⁱ represents the primary modulation signal corresponding to the symbol i, i represents the cyclic shift value of the base signal of the symbol i based on the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

In the embodiments of the present application, the transmitting end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, so that the modulated signal can carry more information, which improves the energy efficiency and spectrum efficiency of the system, thereby reducing system power consumption.

With reference to the third aspect, in some implementations of the third aspect, the receiving end demodulates the modulation symbols to obtain soft information, including: the receiving end performs primary demodulation on the modulation symbols, Obtain first soft information, where the first soft information is used to indicate the cyclic shift value of the modulation symbol based on the base signal of the chirp spread signal; the receiving end performs secondary demodulation on the modulation symbol to obtain the first Two soft information, the second soft information is used to indicate the phase of the phase modulation; the receiving end obtains the soft information based on the first soft information and the second soft information.

In a fourth aspect, a signal transmission device is provided, which is used to execute the method in any possible implementation manner of the foregoing aspects. Specifically, the signal transmission device includes a unit for executing the method in any one of the possible implementation manners of the foregoing aspects.

In a fifth aspect, another signal transmission device is provided, including a processor, which is coupled to a memory and can be used to execute instructions in the memory to implement a method in any possible implementation manner of the foregoing aspects. In a possible implementation manner, the signal transmission device further includes a memory. In a possible implementation manner, the signal transmission device further includes a communication interface, and the processor is coupled with the communication interface.

In an implementation manner, the signal transmission device is a terminal device. When the signal transmission device is a terminal device, the communication interface may be a transceiver, or an input/output interface.

In another implementation manner, the signal transmission device is a chip configured in a terminal device. When the signal transmission device is a chip configured in a terminal device, the communication interface may be an input/output interface.

In an implementation manner, the signal transmission device is a network device. When the signal transmission device is a network device, the communication interface may be a transceiver, or an input/output interface.

In another implementation manner, the signal transmission device is a chip configured in a network device. When the signal transmission device is a chip configured in a network device, the communication interface may be an input/output interface.

In a sixth aspect, a processor is provided, including: an input circuit, an output circuit, and a processing circuit. The processing circuit is used to receive a signal through the input circuit and transmit a signal through the output circuit, so that the processor executes the method in any one of the possible implementation manners of the foregoing aspects.

In the specific implementation process, the above-mentioned processor may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a flip-flop, and various logic circuits. The input signal received by the input circuit may be received and input by, for example, but not limited to, a receiver, and the signal output by the output circuit may be, for example, but not limited to, output to the transmitter and transmitted by the transmitter, and the input circuit and output The circuit can be the same circuit, which is used as an input circuit and an output circuit at different times. This application does not limit the specific implementation of the processor and various circuits.

In a seventh aspect, a processing device is provided, including a processor and a memory. The processor is used to read instructions stored in the memory, and can receive signals through a receiver, and transmit signals through a transmitter, so as to execute the method in any one of the possible implementation manners of the foregoing aspects.

In a possible implementation manner, there are one or more processors and one or more memories.

In a possible implementation manner, the memory may be integrated with the processor, or the memory and the processor may be provided separately.

In the specific implementation process, the memory can be a non-transitory (non-transitory) memory, such as a read only memory (ROM), which can be integrated with the processor on the same chip, or can be set in different On the chip, this application does not limit the type of memory and the way of setting the memory and the processor.

It should be understood that the related data interaction process, for example, sending instruction information may be a process of outputting instruction information from the processor, and receiving capability information may be a process of receiving input capability information by the processor. Specifically, the processed output data may be output to the transmitter, and the input data received by the processor may come from the receiver. Among them, the transmitter and receiver can be collectively referred to as a transceiver.

The above-mentioned processing device may be a chip, and the processor may be implemented by hardware or software. When implemented by hardware, the processor may be a logic circuit, an integrated circuit, etc.; when implemented by software, the processing The processor may be a general-purpose processor, which is implemented by reading software codes stored in the memory. The memory may be integrated in the processor, may be located outside the processor, and exist independently.

In an eighth aspect, a computer program product is provided. The computer program product includes: a computer program (also called code, or instruction), when the computer program is run, the computer can execute any of the above aspects. The method in the implementation mode.

In a ninth aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores a computer program (also called code, or instruction) when it runs on a computer, so that the computer executes any of the above aspects. One possible implementation method.

Description of the drawings

Fig. 1 shows a schematic diagram of a communication system according to an embodiment of the present application.

FIG. 2 shows a schematic flowchart of a signal transmission method according to an embodiment of the present application.

Fig. 3 shows a schematic diagram of a signal spectrum based on phase compensation according to an embodiment of the present application.

FIG. 4 shows a schematic flowchart of another signal transmission method according to an embodiment of the present application.

FIG. 5 shows a schematic diagram of the relationship between the bit signal-to-noise ratio based on phase modulation and the spectral efficiency according to an embodiment of the present application.

FIG. 6 shows a schematic flowchart of another signal transmission method according to an embodiment of the present application.

Fig. 7 shows a schematic diagram of the relationship between bit signal-to-noise ratio and spectral efficiency based on convolutional code encoding in an embodiment of the present application.

FIG. 8 shows a process of processing received signals by the receiving end in an embodiment of the present application.

FIG. 9 shows a schematic block diagram of a signal transmission device according to an embodiment of the present application.

FIG. 10 shows a schematic block diagram of another signal transmission device according to an embodiment of the present application.

Detailed ways

The technical solution in this application will be described below in conjunction with the accompanying drawings.

The technical solutions of the embodiments of this application can be applied to various communication systems, such as: long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (time division duplex) , TDD), the 5th generation (5G) system or the new radio (NR) system or other evolved communication systems, etc.

The terminal equipment in the embodiments of this application may also be referred to as: user equipment (UE), mobile station (MS), mobile terminal (MT), access terminal, user unit, user station, Mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device, etc.

The terminal device may be a device that provides voice/data connectivity to the user, for example, a handheld device with a wireless connection function, a vehicle-mounted device, and so on. At present, some examples of terminals are: mobile phones (mobile phones), tablet computers, notebook computers, handheld computers, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, and augmented reality. (augmented reality, AR) equipment, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in remote medical surgery, and smart grids Wireless terminals in transportation safety (transportation safety), wireless terminals in smart city (smart city), wireless terminals in smart home (smart home), cellular phones, cordless phones, session initiation protocol (session initiation protocol) , SIP) phone, wireless local loop (wireless local loop, WLL) station, personal digital assistant (personal digital assistant, PDA), handheld device with wireless communication function, computing device or other processing device connected to wireless modem, vehicle Devices, wearable devices, terminal devices in a 5G network, or terminal devices in a public land mobile network (PLMN) that will evolve in the future, etc., which are not limited in the embodiment of the present application.

As an example and not a limitation, in the embodiment of the present application, the terminal device may also be a wearable device. Wearable devices can also be called wearable smart devices. It is a general term for the application of wearable technology to intelligently design daily wear and develop wearable devices, such as glasses, gloves, watches, clothing and shoes. A wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories. Wearable devices are not only a kind of hardware device, but also realize powerful functions through software support, data interaction, and cloud interaction. In a broad sense, wearable smart devices include full-featured, large-sized, complete or partial functions that can be achieved without relying on smart phones, such as smart watches or smart glasses, and only focus on a certain type of application function, and need to cooperate with other devices such as smart phones. Use, such as all kinds of smart bracelets and smart jewelry for physical sign monitoring.

In addition, in the embodiments of the present application, the terminal device may also be a terminal device in the Internet of Things (IoT) system. IoT is an important part of the development of information technology in the future. Its main technical feature is to pass items through communication technology. Connect with the network to realize the intelligent network of human-machine interconnection and interconnection of things. The terminal device in the embodiment of the present application may also be a terminal device in machine type communication (MTC). The terminal device of the present application may also be a vehicle-mounted module, vehicle-mounted module, vehicle-mounted component, vehicle-mounted chip, or vehicle-mounted unit built into a vehicle as one or more components or units. The vehicle passes through the built-in vehicle-mounted module, vehicle-mounted module, An on-board component, on-board chip, or on-board unit can implement the method of the present application. Therefore, the embodiments of the present application can be applied to the Internet of Vehicles, such as vehicle to everything (V2X), long term evolution-vehicle (LTE-V) technology, and vehicle-to-vehicle (vehicle-to-vehicle). , V2V) and so on.

In addition, the network device in the embodiment of the present application may be a device used to communicate with a terminal device. The network device may also be called an access network device or a wireless access network device, and may be a transmission reception point (TRP). ), it can also be an evolved base station (evolved NodeB, eNB or eNodeB) in an LTE system, a home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (BBU) , It can also be a wireless controller in a cloud radio access network (CRAN) scenario, or the network device can be a relay station, an access point, a vehicle-mounted device, a wearable device, and a network device in a 5G network or The network equipment in the PLMN network that will evolve in the future can be the access point (AP) in the WLAN, or the gNB in the NR system. The above-mentioned network equipment can also be urban base stations, micro base stations, pico base stations, and micro base stations. Pico base stations, etc., are not limited in the embodiment of the present application.

In a network structure, the network equipment may include a centralized unit (CU) node, or a distributed unit (DU) node, or a radio access network (RAN) that includes a CU node and a DU node. ) Device, or control plane CU node (CU-CP node), user plane CU node (CU-UP node), and RAN device of DU node.

The network equipment provides services for the cell, and the terminal equipment communicates with the cell through the transmission resources (for example, frequency domain resources, or spectrum resources) allocated by the network equipment, and the cell may belong to a macro base station (for example, a macro eNB or a macro gNB, etc.) , It can also belong to the base station corresponding to the small cell. The small cell here can include: metro cell, micro cell, pico cell, femto cell, etc. These small cells have the characteristics of small coverage area and low transmit power, and are suitable for providing high-speed data transmission services.

In the embodiment of the present application, the terminal device or the network device includes a hardware layer, an operating system layer running on the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also referred to as main memory). The operating system can be any one or more computer operating systems that implement business processing through processes, for example, Linux operating systems, Unix operating systems, Android operating systems, iOS operating systems, or windows operating systems. The application layer includes applications such as browsers, address books, word processing software, and instant messaging software. Moreover, the embodiments of the application do not specifically limit the specific structure of the execution body of the method provided in the embodiments of the application, as long as the program that records the codes of the methods provided in the embodiments of the application can be provided in accordance with the embodiments of the application. For example, the execution subject of the method provided in the embodiments of the present application may be a terminal device or a network device, or a functional module in the terminal device or network device that can call and execute the program.

In addition, various aspects or features of the present application can be implemented as methods, devices, or products using standard programming and/or engineering techniques. The term "article of manufacture" used in this application encompasses a computer program accessible from any computer-readable device, carrier, or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (for example, hard disks, floppy disks, or tapes, etc.), optical disks (for example, compact discs (CD), digital versatile discs (DVD)) Etc.), smart cards and flash memory devices (for example, erasable programmable read-only memory (EPROM), cards, sticks or key drives, etc.). In addition, various storage media described herein may represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing, and/or carrying instructions and/or data.

In order to facilitate the understanding of the embodiments of the present application, a communication system suitable for the embodiments of the present application will be described in detail with reference to FIG. 1.

Fig. 1 shows a communication system 100 applied in an embodiment of the present application. The communication system 100 may include at least one network device 110. The network device 110 may be a device that communicates with terminal devices, such as a base station or a base station controller. One network device 110 can provide communication coverage for a certain geographic area, and can communicate with terminal devices located in the coverage area (cell). The wireless communication system 100 also includes one or more terminal devices 120 located within the coverage area of the network device 110. The terminal device 120 may be mobile or fixed.

Each communication device shown in FIG. 1, such as the network device 110 or the terminal device 120, may be configured with multiple antennas, and the multiple antennas may include at least one transmitting antenna for transmitting signals and at least one receiving antenna for receiving signals. In addition, each communication device additionally includes a transmitter chain and a receiver chain. Those of ordinary skill in the art can understand that they may include multiple components related to signal transmission and signal reception (such as processors, modulators, multiplexers, etc.). Converter, demodulator, demultiplexer or antenna, etc.). Therefore, the network device 110 and the terminal device 120 can communicate through multi-antenna technology.

Figure 1 exemplarily shows one network device and two terminal devices. Optionally, the communication system 100 may include multiple network devices and the coverage of one network device may include other numbers of terminal devices. The implementation of this application The example does not limit this.

Optionally, the wireless communication system 100 may also include other network entities such as a network controller and a mobility management entity, and the embodiment of the present application is not limited thereto.

It should be understood that in this article, the foregoing network device may be used as a sending end or a receiving end. Similarly, the foregoing terminal device may be used as a sending end or a receiving end. The signal transmission method described below can be signal transmission between network equipment and network equipment, signal transmission between network equipment and terminal equipment, or signal transmission between terminal equipment and terminal equipment. The application embodiment does not limit this. In other words, the method of the embodiment of the present application is not limited to the scenario of signal transmission between the terminal device and the network device, and it can also be applied to the data transmission between the terminal device and the terminal device, such as side link transmission. The embodiment of the application does not limit this. Exemplarily, the method of the embodiment of the present application can also be applied to vehicle-to-X (V2X) and device-to-device (device-to-device, D2D) communication (for example, communication between UE and UE) , Relay communication and other communications. Therefore, the signal transmission method of the embodiment of the present application will be described below by using the sending end and the receiving end.

In order to facilitate the understanding of the embodiments of the present application, first, a brief description of the terms involved in the present application will be given.

1. Energy efficiency and spectrum efficiency

In the communication system, in order to measure the relationship between energy consumption and transmission rate in the communication process, energy efficiency is proposed, which is used to express the energy consumed by the transmission unit bit system, and its unit is bps/W.

The spectrum efficiency is defined as: the net bit rate (that is, the useful information rate, excluding the error correction code) or the maximum throughput divided by the bandwidth of the communication channel or data link, and the unit is bit/s/Hz.

2. Coherent demodulation and non-coherent demodulation

In a communication system, if the receiving end wants to recover the original digital baseband signal from the modulated high-frequency signal, it needs to demodulate the received signal. The so-called non-coherent demodulation means that there is no need to extract the phase information of the signal. Coherent demodulation needs to know the phase information of the signal.

In theory, the performance of coherent demodulation is better than that of non-coherent demodulation. Due to the complexity of the actual system, the perfect performance of coherent demodulation depends on the accuracy of channel estimation. For non-coherent demodulation, no channel estimation is required and the complexity is low.

3. Hard judgment and soft judgment

The receiver's decoding of the received signal is divided into hard decision and soft decision. Among them, the hard decision is simply to determine the output by setting a threshold, that is, to perform N-bit quantization on the demodulator output signal. In binary terms, it is generally judged as 1 (output 1) if it is larger than the threshold, and judged as 0 (output 0) if it is smaller than the threshold.

Soft decision is that the demodulator connects the demodulated analog signal directly to the decoder to achieve decoding. First, the decision input is quantized into N values, and the most likely original value of each value is calculated by the maximum posterior probability.

In digital communication systems, it can be considered that hard decisions are N-bit quantization, and soft decisions are multi-bit quantization (quantization greater than N bits). The soft decision algorithm is more complicated than the hard decision algorithm, but the bit error rate is lower.

4. Spread spectrum modulation

The data signal is inserted into a pseudo-random sequence with white noise characteristics for transmission, so that the transmission

The bandwidth is hundreds or tens of millions of times larger than the minimum bandwidth required by the original data, which is called spread spectrum.

Spread spectrum communication technology is a way of information transmission, and the frequency bandwidth occupied by the signal is much larger than the minimum bandwidth necessary for the transmitted information. The expansion of the frequency band is done by the sending end through an independent code sequence, which is realized by coding and modulation methods, and has nothing to do with the transmitted information. The receiving end can use the same code sequence to receive and demodulate the relevant synchronization, thereby recovering the information. A commonly used spread spectrum modulation method is chirp spread spectrum. Chirp spread spectrum has the advantages of low power consumption, long distance, low complexity and strong anti-interference ability.

The power amplifier in the transmitter (may be referred to as "power amplifier" for short) can convert a low-power signal into a high-power signal that is emitted in the antenna. The working area of a power amplifier is generally divided into three parts: linear area, non-linear area and peacekeeping area. In the linear region, the input power and output power of the signal have a fixed gain. In the non-linear region, there is no linear relationship between the input power of the signal and the output power. In the saturation region, regardless of the size of the input signal, the output signal power is a constant value. Obviously, the signal needs to avoid entering the non-linear region and saturation region to avoid signal distortion. If the waveform power of the signal changes with time, then the power amplifier needs to fall back to saturate the working area principle of the power amplifier. The larger the backoff value of the power amplifier, the lower the power efficiency of the power amplifier. Therefore, the constant amplitude signal allows the power amplifier to work at the highest efficiency.

For chirp spread spectrum signals, each time domain symbol is a constant amplitude signal, but the entire data waveform composed of different symbols is not constant in amplitude. This is because the phase between different symbols is discontinuous, and the discontinuity of the phase will cause large oscillations in the symbol handover when passing through the actual system filter, which makes the peak to average power ratio of the system (peak to average power ratio, PAPR) is higher and energy efficiency is lower.

In view of this, the present application provides a signal transmission method and device, which can improve the energy efficiency of the system, thereby reducing the power consumption of the system.

The various embodiments provided in the present application will be described in detail below in conjunction with FIG. 2 to FIG. 7.

The embodiments of this application are described by taking the sending end and the receiving end as examples. It should be understood that the sending end can be replaced with a device or chip that can achieve similar functions as the sending end, and the receiving end can also be replaced with a similar function as the receiving end. The name of the device or chip is not limited in the embodiment of this application.

FIG. 2 is a schematic flowchart of a signal transmission method 200 according to an embodiment of the application. The method 200 can be applied to the communication system 100 shown in FIG. 1, but the embodiment of the present application does not limit this. The method 200 may include:

S210: The sending end determines the information bits to be sent.

S220: The sending end performs chirp spread spectrum modulation on the information bits to be sent to obtain a modulated signal.

S230: The transmitting end performs phase compensation on the modulated signal to obtain a signal to be sent, and the phase of the signal to be sent on two adjacent symbols is continuous.

S240: The sending end sends the aforementioned signal to be sent; correspondingly, the receiving end can receive the signal from the sending end.

Optionally, the method 200 further includes:

S250: The receiving end demodulates the received signal to obtain information bits.

Specifically, because constant amplitude signals can make the power amplifier work at the highest efficiency, for non-constant amplitude signals, the smaller the PAPR, the closer the signal is to constant amplitude, and the higher the efficiency of the power amplifier. The higher the efficiency of the power amplifier, the lower the actual power that the power amplifier spends to generate a signal of the same power, so the higher the energy efficiency, in other words, the more energy it saves. Therefore, the embodiment of the present application reduces the PAPR of the signal to be transmitted by means of phase compensation, thereby improving the energy efficiency of the system.

It should be understood that the above-mentioned "the phase of the signal to be transmitted on two adjacent symbols is continuous" refers to: the end phase of the signal to be transmitted on the mth symbol and the start phase of the signal to be transmitted on the m+1th symbol Equal, m is a positive integer. In addition, the above-mentioned phase compensation may mean that the transmitting end respectively multiplies the modulated signal on one or more symbols by a specific phase, so that the end phase and the start phase of the signal on adjacent symbols in the one or more symbols are equal.

Fig. 3 shows a schematic diagram of a signal spectrum based on phase compensation according to an embodiment of the present application. Among them, the horizontal axis is the normalized frequency coordinate, the vertical axis represents the power corresponding to different frequencies, and the gray line represents the signal spectrum after phase compensation. It can be seen from Figure 3 that the spectrum (gray) of the signal after phase compensation is more concentrated than the spectrum (black) of the signal before compensation, the spectrum leakage is reduced, and the energy efficiency is improved. Moreover, due to the addition of phase compensation, There is no longer a simple cyclic shift between adjacent symbols, so the sharp glitch disappears.

As an optional embodiment, in the modulation signal, the initial phase and the end phase of the modulation signal on the first symbol are

Wherein, i represents the cyclic shift value of the modulated signal on the first symbol based on the base signal of the chirp spread spectrum signal, B represents the frequency sweep range, T represents the length of the first symbol, and i is an integer greater than 0, B and T are both greater than 0; the transmitting end performs phase compensation on the modulated signal, including: the transmitting end multiplies the modulated signal on the first symbol by

Obtain the signal to be sent on the first symbol.

The foregoing embodiment only takes the first symbol as an example, and introduces a method of performing phase compensation on the modulated signal on the first symbol. In the actual application process, the transmitting end may perform phase compensation on the modulated signal on one or more symbols (for example, the modulated signal on all symbols), which is not limited in the embodiment of the present application.

It should be understood that the modulated signal on the first symbol refers to: the transmitter performs resource mapping after chirp spreading modulation on the information bits to be sent, that is, the modulated signal is mapped to the time-frequency resource and then sent out. The first symbol is in the real-time domain. A symbol on the.

Therefore, in the embodiment of the present application, the transmitting end can multiply the modulation signal on one or more symbols in the time domain by the reverse phase of the modulation signal, so that the modulation signal on the one or more symbols starts The phase and the end phase are both 0, so that the phase continuity of the modulation signal of two adjacent symbols can be realized.

Exemplarily, it is assumed that the base signal of the chirp spread spectrum signal can be expressed in the following form:

Among them, exp(a) represents e ^a , B represents the frequency sweep range, and T represents the symbol length. For a symbol, t∈[0,T], when t=0, the initial phase of the symbol is

When t=T, the end phase of the symbol is

For chirp spread spectrum signal, M=2 ^SF is an even number, SF is spreading factor (spreading factor), representing the number of information bits carried by a chirp symbol, when the sweep range B of the above signal is given, send The end can change the length of the symbol by adjusting the SF. Therefore, the above start phase and end phase are equal, and both are 0.

In the embodiment of the present application, it is assumed that the modulated signal on the first symbol is cyclically shifted by i, which can be expressed as s ⁱ (t), and the initial phase and the end phase of the modulated signal on the first symbol are

Then the signal to be transmitted obtained by the transmitting end after performing phase compensation on the modulated signal on the first symbol can be expressed as:

In this way, the start phase and the end phase of the signal to be sent on the first symbol are both zero.

For the receiving end, the receiving end demodulates the received signal to obtain information bits, either by coherent demodulation or non-coherent demodulation, which is not limited in the embodiment of the present application. In the embodiment of this application, for the signal to be transmitted after phase compensation, if the receiving end adopts coherent demodulation, the receiving end needs to perform additional phase compensation operations, that is, perform additional phase compensation operations on the received signal during demodulation. The phase compensation is similar to the transmitting end; if the receiving end adopts the non-coherent demodulation method, the receiving end can adopt the demodulation method of the prior art, which will not be repeated here.

As an optional embodiment, before the transmitting end performs spread spectrum modulation on the information bits to be sent, the method further includes: the transmitting end performs convolutional code encoding on the information bits to be sent to obtain Coded bits; the sending end performs chirp spread spectrum modulation on the information bits to be sent, including: the sending end performs chirp spread spectrum modulation on the coded bits to obtain the modulation symbols.

The embodiment of the application combines convolutional code encoding and chirp spread spectrum modulation, and performs phase compensation on the modulated signal, so that the phase of the signal to be transmitted obtained after phase compensation is continuous on two adjacent symbols, which effectively reduces The PAPR of the signal to be sent, and the large coding gain of the convolutional code, can improve the detection performance of the receiving end, that is, the receiving end can achieve correct demodulation in a lower signal-to-noise ratio environment, which is equivalent to the receiving end achieving the same detection performance The power required at the time is lower. Therefore, the embodiments of the present application can improve the energy efficiency of the system, thereby reducing the power consumption of the system.

Optionally, the aforementioned convolutional code encoding can also be replaced with other encoding methods. In other words, the embodiment of the present application can also be implemented by combining other encoding methods with chirp spread spectrum modulation. Illustratively, the aforementioned convolutional code encoding can be replaced These are low density parity check (LDPC) codes, turbo codes, etc., which are not limited in the embodiment of the present application.

FIG. 4 is a schematic flowchart of another signal transmission method 400 according to an embodiment of the application. The method 400 can be applied to the communication system 100 shown in FIG. 1, but the embodiment of the present application does not limit this. The method 400 may include:

S410: The sending end determines the information bits to be sent.

S420: The sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent to obtain a modulated signal;

S430: The sending end sends the modulated signal; correspondingly, the receiving end can receive the signal from the sending end.

Optionally, the method 200 further includes:

S440: The receiving end demodulates the received signal to obtain information bits.

It should be understood that the above-mentioned chirp spread spectrum modulation and phase modulation belong to the modulation process of the information bits to be sent by the sending end. The sending end can perform chirp spread spectrum modulation on the information bits to be sent first, and then perform phase modulation, or can also perform the information bits to be sent first. Phase modulation is followed by chirp spread spectrum modulation. The embodiment of the present application does not limit the sequence of modulation.

FIG. 5 shows a schematic diagram of the relationship between the bit signal-to-noise ratio based on phase modulation and the spectral efficiency according to an embodiment of the present application. Among them, the black dashed line is the Shannon theoretical limit, the line marked with a hollow five-pointed star represents the curve of spectral efficiency with bit signal-to-noise ratio after soft information decoding combined with phase modulation, and the line marked with a solid five-pointed star represents a line based on hard decoding combined with phase modulation. After the spectrum efficiency varies with the bit signal-to-noise ratio, the line marked by the triangle is the reference performance curve of the prior art.

It can be seen from Figure 5 that the line marked with a hollow five-pointed star (or a line marked with a solid five-pointed star) can achieve the same spectral efficiency in a lower bit signal-to-noise ratio environment compared to the line marked with a triangle. In other words In other words, it can achieve higher spectral efficiency under the same bit signal-to-noise ratio environment. Therefore, phase modulation improves energy efficiency and spectrum efficiency.

As an optional embodiment, the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, including: the sending end performs chirp spread spectrum modulation on the information bits to be sent to obtain a first level Modulated signal; the transmitting end performs phase modulation on the primary modulation signal to obtain the modulated signal.

Specifically, the above chirp spread spectrum modulation can be called primary modulation, and the above phase modulation can be called secondary modulation. The transmitting end can perform primary modulation first to obtain a primary modulation signal, and then perform secondary modulation on the primary modulation signal. Level modulation to obtain the modulated signal to be sent.

As an optional embodiment, in the modulation signal, the modulation signal on the first symbol is (s ⁱ )′=s ⁱ ×e ^φ ; where s ⁱ represents the first-level modulation on the first symbol Signal, i represents the cyclic shift value of the primary signal of the primary modulation signal on the first symbol based on the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

In QPSK,

or

When the phase modulation method is

In QPSK,

As an optional embodiment, before the transmitting end performs spread spectrum modulation and phase modulation on the information bits to be sent, the method further includes: the transmitting end performs convolutional coding on the information bits to be sent Encoding to obtain coded bits; the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, including: the sending end performs chirp spread spectrum modulation and phase modulation on the coded bits to obtain the modulation symbol.

Optionally, the aforementioned convolutional code encoding can also be replaced with other encoding methods. In other words, the embodiment of this application can also be implemented by combining other encoding methods with chirp spread spectrum modulation. Illustratively, the aforementioned convolutional code can be replaced with Low density parity check (LDPC) codes, turbo codes, etc., which are not limited in the embodiment of the present application.

FIG. 6 is a schematic flowchart of another signal transmission method 600 according to an embodiment of the application. The method 600 can be applied to the communication system 100 shown in FIG. 1, but the embodiment of the present application does not limit this. The method 600 may include:

S610: The sending end determines information bits to be sent.

S620: The sending end performs convolutional code coding on the information bits to be sent to obtain coded bits.

S630: The transmitting end performs chirp spread spectrum modulation on the coded bits to obtain a modulated signal.

S640: The transmitting end sends the modulated signal; then, correspondingly, the receiving end receives the modulated signal.

S650. The receiving end demodulates the modulated signal to obtain soft information (also referred to as soft decision information or other names).

S660: The receiving end performs convolutional decoding based on the soft information to obtain information bits.

Optionally, the above S650 and S660 can also be replaced with:

The receiving end demodulates the modulated signal to obtain hard information (also called hard decision information or other names);

The receiving end performs convolutional decoding based on the hard information to obtain information bits.

As an optional embodiment, the above-mentioned receiving end may choose to adopt soft decision or hard decision according to its own computing capability, that is, choose to determine the above-mentioned soft information or hard information.

It should be understood that in a possible implementation manner, the receiving end performs convolutional decoding on the soft information obtained by demodulation, which can be applied to the scenario of uplink transmission, because the network equipment has strong computing power, and this soft information is used. The way of decoding can improve the energy efficiency of the system. For downlink transmission, terminal devices (such as IoT devices) are not very capable of computing, and hard decoding can also be used, while taking into account energy efficiency and complexity, thereby improving system performance.

Fig. 7 shows a schematic diagram of the relationship between bit signal-to-noise ratio and spectral efficiency based on convolutional code encoding in an embodiment of the present application. Among them, the black dashed line is the Shannon theoretical limit, the line marked by the open circle represents the curve of the spectral efficiency of convolutional code encoding combined with soft information decoding with bit signal-to-noise ratio, and the line marked by the solid circle represents the convolutional code encoding combined based on hard The spectrum efficiency of decoding varies with the bit signal-to-noise ratio, and the line marked with a triangle is the reference performance curve of the prior art.

It can be seen from Figure 7 that the line marked by the hollow circle (or the line marked by the solid circle) can achieve the same spectral efficiency under the environment of lower bit signal-to-noise ratio compared with the line marked by the triangle. In other words, It can achieve higher spectral efficiency under the same bit signal-to-noise ratio environment. Therefore, the convolutional code encoding improves energy efficiency and spectrum efficiency. Moreover, the combination of convolutional code encoding and soft information decoding can achieve higher gains, and further improve the energy efficiency and spectrum efficiency of the system.

As an optional embodiment, the above soft information is calculated based on non-coherent demodulation and log likelihood ratio (LLR).

Exemplarily, no matter whether the sending end sends bit 1 or bit 0, the receiving end may misjudge. If the signal y is received, the ratio of the probability that the receiving end is correctly judged as 1 and the probability of being correctly judged as 0 is the likelihood ratio, and the logarithm is the log-likelihood ratio LLR. Assuming that the received signal is y, the LLR of a certain information bit b can be expressed as:

Among them, p(y|b=1) represents the conditional probability density of y when the information bit b is 1, and p(y|b=0) represents the conditional probability density of y when the information bit b is 0.

In the embodiment of the present application, the modulated signal on one symbol contains SF=log ₂ M bits of information, and the value of a certain bit is associated with multiple symbols. For example, SF=4, M=16, it means that there are 16 symbols in the symbol set of SF=4, and the modulated signal on each symbol contains 4 bits of information. It is assumed that the modulated signal on symbol 1 contains The information bit is 0000, the information bit contained in the modulated signal on symbol 2 is 0001, the information bit contained in the modulated signal on symbol 3 is 0011, and so on. Therefore, among the above three symbols, the symbol whose first information bit is 0 includes symbols 1, symbol 2, symbol 3 and so on.

It should be understood that the modulated signal on a symbol means that the transmitter performs resource mapping after chirp spreading modulation on the information bits to be sent, that is, the modulated signal is mapped to the time-frequency resource and then sent out. The symbol is in the immediate domain. Of a symbol.

In the embodiment of the present application, b _{k is used to} represent the value of the k-th information bit, and b _k =1 or b _k =0. k∈[1,2,…,log ₂ M]. Thus, the received signal y can be obtained for the purposes of the k-th information bit values of χ _k B probability is the probability of all symbols of the modulated signal value of k information bits of B _k and χ satisfy The following formula:

Among them, Pr represents probability,

Represents the set of symbols with the value of χ for all the k-th information bits, the value of χ is 0 or 1, and s ⁱ represents the modulated signal on the symbols of all the k-th information bits with the value of χ,

Indicates that the symbol corresponding to ^{s i belongs to the set}

Assuming that the transmission probability of the modulated signal on all symbols is equal, _{the LLR of b k} can be expressed as:

Since the chirp spread spectrum signal in the embodiment of this application is for an additive white Gaussian noise (AWGN) channel, as an optional embodiment, for the value b _{k of the kth} bit, The soft information satisfies the following formula:

among them,

Represents the set of symbols whose value is χ of the k-th information bit, χ is 0 or 1, k∈{0,1,...,log ₂ M-1}, s ⁱ represents the modulated signal on symbol i ,

Indicates that the symbol corresponding to ^{s i belongs to the set}

I ₀ is the Bessel function, σ ² is the energy of the noise,

γ _i =<s ^j e ^jφ +n, s ⁱ >, i represents the cyclic shift value of the base signal of the chirp spreading signal based on the first symbol, and s ^j represents the modulation corresponding to the symbol sent by the receiving end assuming that the sending end Signal, M=B×T, B represents the system bandwidth, T represents the length of the first symbol, i is an integer greater than 0, and both B and T are greater than 0.

For ease of understanding, the derivation process of the above soft information (ie formula (2)) is described in detail below.

Exemplarily, for the receiving end, assuming that the signal received by the receiving end is y, the ^{posterior probability that the modulated signal on the transmitted symbol is s i} can be represented by Pr(s ⁱ |y), i∈{0,..., M-1}, M=2 ^SF . The maximum a posteriori (MAP) criterion is to select the symbol that can maximize the posterior probability among the possible M symbols. This criterion can be shown by minimizing the detection error rate. According to the Bayes criterion, the posterior probability can be expressed as

Among them, p(y|s ⁱ ) is a conditional probability density function (probability density function, PDF), which means that when the modulated signal on the sending symbol is s ⁱ , the PDF of the received signal y observed by the receiving end is also called like Ran function. Pr(s ⁱ ) is a priori function that represents the transmission probability of the modulated signal si. The denominator can be regarded as a normalized quantity, independent of the sending symbol.

In general, it is assumed that the transmission probability of the modulated signal on all symbols is equal, that is

Then the MAP criterion can be simplified to a maximum likelihood (ML) criterion.

FIG. 8 shows a process of processing the received signal by the receiving end in an embodiment of the present application. As shown in FIG. 8, the receiving end inputs the received signal y to each correlator respectively. The number of correlators is 2 ^SF -1, so the receiving end can output 2 ^SF -1 values through the correlator. Assuming that the correlation value γ _i is the output value of the correlator s ⁱ , it can be expressed as

γ _i =<y,s ⁱ >=<s ^j e ^jφ +n,s ⁱ >,

Among them, s ^j represents the modulated signal corresponding to the symbol sent by the receiving end assuming the sending end, and e ^jφ represents that because there is no channel estimation, the received signal remains through the channel and has a phase change.

Assuming that the noise energy of the additive white Gaussian noise (AWGN) channel is σ ² , the correlation value γ _i can be expressed as

among them

It is easy to prove that w～N(0,Mσ ² ) still obeys the complex Gaussian distribution, and the noise energy is Mσ ² .

According to the orthogonality between symbols

Non-coherent demodulation means that the correlator can only get the absolute value of the correlation |γ _i |, so

When i=j, Υ _i obeys the non-central chi-square (chi-square) distribution, and the degree of freedom is 2,

Among them, I ₀ is the Bessel function.

When i≠j, Υ _i obeys chi-square distribution

Therefore, the maximum likelihood expression of incoherent demodulation is:

Therefore, combining the correlation value γ _i and the above formula (1), for the value b _{k of} the k-th bit, the incoherent LLR can be expressed as:

As shown in Figure 8, the receiving end can ^{obtain 2 SF} -1 soft information ^{according to the 2 SF} -1 correlation values ^{, and input the 2 SF} -1 soft information into the convolutional decoder for decoding, and it can be restored Out information bits.

As an optional embodiment, the above soft information is calculated based on coherent demodulation and log likelihood ratio (LLR). Optionally, similar to incoherent demodulation, combined with channel information, for the value b _{k of} the k-th bit, the soft information satisfies the following formula:

among them,

Means taking the real part, ||y|| ² means the modulus square of y, that is, the sum of the squares of the real part and the imaginary part,

Represents the conjugate of ^{s i.}

It should be understood that the receiving end of the embodiment of the present application may use coherent demodulation or non-coherent demodulation. In other words, the present application does not limit the demodulation method used by the receiving end.

As an optional embodiment, the spread spectrum modulation is chirp spread spectrum modulation, the modulation symbol has also undergone phase modulation, and the modulation signal corresponding to the symbol i is

(s ⁱ )′=s ⁱ ×e ^φ ;

Wherein, s ⁱ represents the primary modulation signal corresponding to the symbol i, i represents the cyclic shift value of the base signal of the symbol i based on the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

As an optional embodiment, the receiving end demodulates the modulation symbols to obtain soft information includes: the receiving end performs primary demodulation on the modulation symbols to obtain the first soft information, and The first soft information is used to indicate the cyclic shift value of the modulation symbol based on the base signal of the chirp spread spectrum signal; the receiving end performs secondary demodulation on the modulation symbol to obtain the second soft information. The soft information is used to indicate the phase of the phase modulation; the receiving end obtains the soft information based on the first soft information and the second soft information.

For the above-mentioned modulated signals that have undergone chirp spread spectrum modulation and phase modulation, the receiving end can be divided into primary demodulation and secondary demodulation during demodulation. Demodulation is the demodulation for phase modulation. In a possible implementation manner, the receiving end first performs primary demodulation to obtain the first soft information, and then performs secondary demodulation to obtain the second soft information, thereby obtaining the soft information required for convolutional decoding. However, it should be understood that the embodiment of the present application does not limit the sequence of primary demodulation and secondary demodulation.

As an optional embodiment, if the receiving end adopts coherent demodulation, similar to the above formula (4), for the modulated signal (s ⁱ )′ on the symbol i, the soft information satisfies the following formula:

As an optional embodiment, if the receiving end adopts non-coherent demodulation, similar to the above formula (2), for the modulated signal (s ⁱ )′ on the symbol i, the soft information satisfies the following formula:

It should be understood that the size of the sequence numbers of the foregoing processes does not mean the order of execution, and the execution order of the processes should be determined by their functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

Above, the method provided by the embodiment of the present application has been described in detail with reference to FIGS. 2 to 8. Hereinafter, the device provided by the embodiment of the present application will be described in detail with reference to FIG. 9 and FIG. 10.

The embodiment of the present application provides a signal transmission device. In a possible implementation manner, the device is used to implement the steps or procedures corresponding to the receiving end in the foregoing method embodiments. In another possible implementation manner, the device is used to implement the steps or procedures corresponding to the sending end in the foregoing method embodiments.

FIG. 8 is a schematic block diagram of a signal transmission device provided by an embodiment of the present application. As shown in FIG. 8, the device 800 may include a processing unit 810 and a transceiver unit 820.

In a possible design, the device 800 can implement the steps or processes performed by the sending end corresponding to the method embodiment 200 above, wherein the processing unit 810 is configured to perform processing related to the sending end in the method embodiment 200 above. The transceiving unit 820 is configured to perform the transceiving-related operations of the transmitting end in the method embodiment 200 above.

Exemplarily, the processing unit 810 is configured to: determine the information bits to be sent; perform chirp spread spectrum modulation on the information bits to be sent to obtain a modulated signal; and perform phase compensation on the modulated signal to obtain the information bit to be sent Signal, the phase of the signal to be sent on two adjacent symbols is continuous; the transceiver unit 820 is used to send the signal to be sent.

Optionally, in the modulation signal, the initial phase and the end phase of the modulation signal on the first symbol are

Where i represents the cyclic shift value of the modulated signal on the first symbol based on the base signal of the chirp spread spectrum signal, B represents the frequency sweep range, T represents the length of the first symbol, and i is an integer greater than 0, B and T are both greater than 0; the processing unit 810 is specifically configured to: multiply the modulated signal on the first symbol by

Obtain the signal to be sent on the first symbol.

Optionally, the processing unit 810 is specifically configured to: before performing spread spectrum modulation on the information bits to be sent, perform convolutional code encoding on the information bits to be sent to obtain coded bits; and perform chirp on the coded bits. Spread spectrum modulation to obtain the modulation symbol.

The signal transmission device of the embodiment of the present application performs phase compensation on the modulated signal obtained after chirp spread spectrum modulation through the transmitting end, so that the phase of the signal to be transmitted obtained after phase compensation is continuous on two adjacent symbols, which effectively reduces The PAPR of the signal to be sent improves the energy efficiency of the system, thereby reducing system power consumption.

In a possible design, the device 800 can implement the steps or procedures performed by the sending end corresponding to the method embodiment 400 above, wherein the processing unit 810 is configured to perform the processing related to the sending end in the method embodiment 400 above. The transceiving unit 820 is configured to perform the transceiving-related operations of the transmitting end in the method embodiment 400 above.

Exemplarily, the processing unit 810 is configured to: determine the information bits to be sent; and, perform chirp spread spectrum modulation and phase modulation on the information bits to be sent to obtain a modulated signal; the transceiver unit 820 is configured to:述 Modulation signal.

Optionally, the processing unit 810 is specifically configured to: perform spread spectrum modulation on the information bits to be sent to obtain a primary modulation signal; and perform phase modulation on the primary modulation signal to obtain the modulation signal.

Optionally, in the modulated signal, the modulated signal corresponding to the first symbol is (s ⁱ )′=s ⁱ ×e ^φ ; where s ⁱ represents the first-level modulated signal corresponding to the first symbol, and i represents The first symbol is based on the cyclic shift value of the base signal of the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

Optionally, the processing unit 810 is specifically configured to: before performing spread spectrum modulation and phase modulation on the information bits to be sent, perform convolutional code encoding on the information bits to be sent to obtain coded bits; The bits are subjected to chirp spread spectrum modulation and phase modulation to obtain the modulation symbol.

The signal transmission device of the embodiment of the present application performs chirp spread spectrum modulation and phase modulation on the information bits to be sent by the transmitting end, so that the modulated signal can carry more information, which improves the energy efficiency and spectrum efficiency of the system, thereby reducing system power consumption.

In another possible design, the device 800 can implement the steps or processes performed by the receiving end corresponding to the above method embodiment 600, wherein the transceiver unit 820 is used to perform the receiving and sending of the above method embodiment 600. For related operations, the processing unit 810 is configured to perform operations related to processing on the receiving end in the method embodiment 600 described above.

Exemplarily, the transceiver unit 820 is used to: receive a modulated signal, the modulated signal is generated by chirp spread spectrum modulation on coded bits obtained through convolutional code encoding; the processing unit 810 is used to: perform a modulation on the modulated signal Demodulate to obtain soft information; and, based on the soft information, perform convolutional decoding to obtain information bits.

Optionally, the soft information is determined based on non-coherent demodulation and log-likelihood ratio (LLR).

Optionally, for the value b _{k of} the k-th bit, the soft information satisfies the following formula:

Among them, k∈[1,2,…,log ₂ M], i∈{0,…,M-1},

Indicates that the symbol corresponding to ^{s i belongs to the set}

I ₀ is the Bessel function, σ ² is the energy of the noise,

Optionally, the modulation symbol has also undergone phase modulation, and the modulation signal corresponding to the symbol i is (s ⁱ )′=s ⁱ ×e ^φ ; where s ⁱ represents the primary modulation signal corresponding to the symbol i , I represents the cyclic shift value of the symbol i based on the base signal of the chirp spread spectrum signal, and φ represents the phase of the phase modulation.

Optionally, the processing unit 810 is specifically configured to: perform primary demodulation on the modulation symbol to obtain first soft information, where the first soft information is used to indicate that the modulation symbol is based on the basis of the chirp spread signal. The cyclic shift value of the signal; perform secondary demodulation on the modulation symbol to obtain second soft information, where the second soft information is used to indicate the phase of the phase modulation; based on the first soft information and the The second soft information is to obtain the soft information.

The signal transmission method of the embodiment of the present application can achieve the same spectrum efficiency in a lower bit signal-to-noise ratio environment. In other words, it can achieve higher spectrum efficiency in the same bit signal-to-noise ratio environment, thereby improving The energy efficiency of the system reduces the power consumption of the system.

It should be understood that the device 800 here is embodied in the form of a functional unit. The term "unit" here can refer to application specific integrated circuits (ASICs), electronic circuits, processors used to execute one or more software or firmware programs (such as shared processors, proprietary processors, or groups). Processor, etc.) and memory, merged logic circuits, and/or other suitable components that support the described functions. In an optional example, those skilled in the art can understand that the apparatus 800 may be specifically the sending end in the foregoing embodiment, and may be used to execute each process and/or step corresponding to the sending end in the foregoing method embodiment, or, The apparatus 800 may be specifically the receiving end in the foregoing embodiment, and may be used to execute each process and/or step corresponding to the receiving end in the foregoing method embodiment. To avoid repetition, details are not described herein again.

The apparatus 800 of each of the foregoing solutions has the function of implementing the corresponding steps performed by the sending end in the foregoing method, or the apparatus 800 of each of the foregoing solutions has the function of implementing corresponding steps performed by the receiving end of the foregoing method. The function can be realized by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions; for example, the communication unit can be replaced by a transceiver (for example, the sending unit in the communication unit can be replaced by a transmitter, and the receiving unit in the communication unit can be replaced by a receiver. Machine replacement), other units, such as processing units, etc., can be replaced by processors to perform the transceiver operations and related processing operations in each method embodiment respectively.

In addition, the aforementioned communication unit may also be a transceiver circuit (for example, it may include a receiving circuit and a transmitting circuit), and the processing unit may be a processing circuit. In the embodiment of the present application, the device in FIG. 8 may be the receiving end or the sending end in the foregoing embodiment, or may be a chip or a chip system, such as a system on chip (SoC). Wherein, the communication unit may be an input/output circuit or a communication interface; the processing unit is a processor, microprocessor, or integrated circuit integrated on the chip. There is no limitation here.

FIG. 10 shows another signal transmission device 1000 provided by an embodiment of the present application. The device 1000 includes a processor 1010 and a transceiver 1020. The processor 1010 and the transceiver 1020 communicate with each other through an internal connection path, and the processor 1010 is used to execute instructions to control the transceiver 1020 to send signals and/or receive signals.

Optionally, the device 1000 may further include a memory 1030, and the memory 1030, the processor 1010, and the transceiver 1020 communicate with each other through an internal connection path. The memory 1030 is used to store instructions, and the processor 1010 can execute the instructions stored in the memory 1030. In a possible implementation manner, the apparatus 1000 is configured to implement various processes and steps corresponding to the sending end in the foregoing method embodiment. In another possible implementation manner, the apparatus 1000 is configured to implement various processes and steps corresponding to the receiving end in the foregoing method embodiment.

It should be understood that the apparatus 1000 may be specifically the transmitting end or the receiving end in the foregoing embodiment, and may also be a chip or a chip system. Correspondingly, the transceiver 1020 may be the transceiver circuit of the chip, which is not limited here. Specifically, the apparatus 1000 may be used to execute various steps and/or procedures corresponding to the sending end or the receiving end in the foregoing method embodiments. Optionally, the memory 1030 may include a read-only memory and a random access memory, and provide instructions and data to the processor. A part of the memory may also include a non-volatile random access memory. For example, the memory can also store device type information. The processor 1010 may be used to execute instructions stored in the memory, and when the processor 1010 executes the instructions stored in the memory, the processor 1010 is used to execute the steps of the method embodiment corresponding to the sending end or the receiving end. And/or process.

In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or instructions in the form of software. The steps of the method disclosed in combination with the embodiments of the present application may be directly embodied as execution and completion by a hardware processor, or execution and completion by a combination of hardware and software modules in the processor. The software module can be located in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware. To avoid repetition, it will not be described in detail here.

It should be noted that the processor in the embodiment of the present application may be an integrated circuit chip with signal processing capability. In the implementation process, the steps of the foregoing method embodiments can be completed by hardware integrated logic circuits in the processor or instructions in the form of software. The above-mentioned processor may be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components . The methods, steps, and logical block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor or the like. The steps of the method disclosed in the embodiments of the present application may be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of hardware and software modules in the decoding processor. The software module can be located in a mature storage medium in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, registers. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

It can be understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. Among them, the non-volatile memory can be read-only memory (ROM), programmable read-only memory (programmable ROM, PROM), erasable programmable read-only memory (erasable PROM, EPROM), and electrically available Erase programmable read-only memory (electrically EPROM, EEPROM) or flash memory. The volatile memory may be random access memory (RAM), which is used as an external cache. By way of exemplary but not restrictive description, many forms of RAM are available, such as static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), and synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (synchlink DRAM, SLDRAM) ) And direct memory bus random access memory (direct rambus RAM, DR RAM). It should be noted that the memories of the systems and methods described herein are intended to include, but are not limited to, these and any other suitable types of memories.

According to the method provided by the embodiments of the present application, the present application also provides a computer program product. The computer program product includes: computer program code. When the computer program code runs on a computer, the computer executes the steps shown in FIGS. 2 to 8. The steps or processes performed by the sending end or the receiving end in the illustrated embodiment.

According to the method provided by the embodiments of the present application, the present application also provides a computer-readable storage medium that stores program code, which when the program code runs on a computer, causes the computer to execute FIG. 2 to FIG. Steps or processes performed by the sending end or the receiving end in the embodiment shown in 8.

According to the method provided in the embodiment of the present application, the present application also provides a communication system, which includes the aforementioned one or more sending ends and one or more receiving ends.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, it can be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server, or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a high-density digital video disc (digital video disc, DVD)), or a semiconductor medium (for example, a solid state disk (solid state disc, SSD)) etc.

The network equipment in each of the above-mentioned device embodiments corresponds completely to the network equipment or terminal equipment in the terminal equipment and method embodiments, and the corresponding modules or units execute the corresponding steps. For example, the communication unit (transceiver) executes the receiving or the terminal equipment in the method embodiments. In the sending step, other steps except sending and receiving can be executed by the processing unit (processor). For the functions of specific units, refer to the corresponding method embodiments. Among them, there may be one or more processors.

The terms "component", "module", "system", etc. used in this specification are used to denote computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, the component may be, but is not limited to, a process, a processor, an object, an executable file, an execution thread, a program, and/or a computer running on a processor. Through the illustration, both the application running on the computing device and the computing device can be components. One or more components may reside in processes and/or threads of execution, and components may be located on one computer and/or distributed between two or more computers. In addition, these components can be executed from various computer-readable storage media having various data structures stored thereon. The component can be based on, for example, a signal having one or more data packets (e.g. data from two components interacting with another component in a local system, a distributed system, and/or a network, such as the Internet that interacts with other systems through a signal) Communicate through local and/or remote processes.

It should be understood that "at least one" in this document refers to one or more, and "plurality" refers to two or more than two. "And/or" describes the association relationship of the associated objects, indicating that there can be three relationships, for example, A and/or B, which can mean: A alone exists, A and B exist at the same time, and B exists alone, where A, B can be singular or plural. The character "/" generally indicates that the associated objects before and after are in an "or" relationship. "The following at least one item (a)" or similar expressions refers to any combination of these items, including any combination of a single item (a) or a plurality of items (a). For example, at least one of a, b, and c can mean: a, or b, or c, or a and b, or a and c, or b and c, or a, b and c, where a, b, c can be single or multiple.

Those of ordinary skill in the art may realize that the various illustrative logical blocks and steps described in the embodiments disclosed herein can be implemented by electronic hardware or a combination of computer software and electronic hardware. achieve. Whether these functions are executed by hardware or software depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and conciseness of description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the various embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit.

In the foregoing embodiments, the functions of each functional unit may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented by software, it can be implemented in the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions (programs). When the computer program instructions (programs) are loaded and executed on the computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website, computer, server, or data center. Transmission to another website, computer, server or data center via wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center integrated with one or more available media. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, and a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)).

If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application essentially or the part that contributes to the existing technology or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (read-only memory, ROM), random access memory (random access memory, RAM), magnetic disks or optical disks and other media that can store program codes. .

The above are only specific implementations of this application, but the protection scope of this application is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in this application. Should be covered within the scope of protection of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

A signal transmission method, characterized in that it comprises:

The sending end determines the information bits to be sent;

The sending end performs chirp spread spectrum modulation on the information bits to be sent to obtain a modulated signal;

The transmitting end performs phase compensation on the modulated signal to obtain a signal to be sent, and the phase of the signal to be sent is continuous on two adjacent symbols;

The sending end sends the signal to be sent.
The signal transmission method according to claim 1, wherein in the modulated signal, the initial phase and the end phase of the modulated signal on the first symbol are
Where i represents the cyclic shift value of the modulated signal on the first symbol based on the base signal of the chirp spread spectrum signal, B represents the frequency sweep range, T represents the length of the first symbol, and i is an integer greater than 0, Both B and T are greater than 0;

The phase compensation performed by the transmitting end on the modulated signal includes:

The transmitting end multiplies the modulated signal on the first symbol by
Obtain the signal to be sent on the first symbol.
The signal transmission method according to claim 1 or 2, characterized in that, before the transmitting end performs spread spectrum modulation on the information bits to be sent, the method further comprises:

The sending end performs convolutional code encoding on the information bits to be sent to obtain coded bits;

The chirp spread spectrum modulation performed by the sending end on the information bits to be sent includes:

The sending end performs chirp spread spectrum modulation on the coded bits to obtain the modulation symbol.
A signal transmission method, characterized in that it comprises:

The sending end determines the information bits to be sent;

The sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent to obtain a modulated signal;

The sending end sends the modulated signal.
The signal transmission method according to claim 4, wherein the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, comprising:

The sending end performs chirp spread spectrum modulation on the information bits to be sent to obtain a first-level modulated signal;

The transmitting end performs phase modulation on the primary modulation signal to obtain the modulation signal.
The signal transmission method according to claim 5, wherein in the modulated signal, the modulated signal on the first symbol is

(s i )′=s i ×e φ ;

Wherein, s i represents the primary modulation signal on the first symbol, i represents the cyclic shift value of the primary modulation signal on the first symbol based on the chirp spread signal, and φ represents the phase modulation的相。 The phase.
The signal transmission method according to any one of claims 4 to 6, characterized in that, before the sending end performs chirp spread spectrum modulation and phase modulation on the information bits to be sent, the method further comprises:

The sending end performs convolutional code encoding on the information bits to be sent to obtain coded bits;

The sending end performing chirp spread spectrum modulation and phase modulation on the information bits to be sent includes:

The transmitting end performs chirp spread spectrum modulation and phase modulation on the coded bits to obtain the modulation symbol.
A signal transmission method, characterized in that it comprises:

The receiving end receives a modulated signal, where the modulated signal is generated by chirp spread spectrum modulation on coded bits obtained through convolutional code encoding;

The receiving end demodulates the modulated signal to obtain soft information;

The receiving end performs convolutional decoding based on the soft information to obtain information bits.
The signal transmission method according to claim 8, wherein the soft information is determined based on non-coherent demodulation and log-likelihood ratio (LLR).
The signal transmission method according to claim 9, wherein for the value b k of the k-th bit, the soft information satisfies the following formula:

Among them, k∈[1,2,…,log 2 M], i∈{0,…,M-1},
Indicates the set of symbols whose value is χ of the k-th information bit, χ is valued as 0 or 1, and s i represents the modulated signal on symbol i,
Indicates that the symbol corresponding to s i belongs to the set
I 0 is the Bessel function, σ 2 is the energy of the noise,
γ i =<s j e jφ +n, s i >, i represents the cyclic shift value of the base signal of the chirp spreading signal based on the first symbol, and s j represents the modulation corresponding to the symbol sent by the receiving end assuming that the sending end Signal, M=B×T, B represents the frequency sweep range, T represents the length of the symbol i, i is an integer greater than 0, and both B and T are greater than 0.
The signal transmission method according to claim 8 or 9, wherein the modulation symbol has also undergone phase modulation, and the modulation signal corresponding to the symbol i is:

(s i )′=s i ×e φ ;

Wherein, s i represents the primary modulation signal corresponding to the symbol i, i represents the cyclic shift value of the base signal of the symbol i based on the chirp spread spectrum signal, and φ represents the phase of the phase modulation.
The signal transmission method according to claim 11, wherein the receiving end demodulates the modulation symbol to obtain soft information, comprising:

The receiving end performs one-stage demodulation on the modulation symbol to obtain first soft information, where the first soft information is used to indicate the cyclic shift value of the base signal of the modulation symbol based on the chirp spread signal;

The receiving end performs secondary demodulation on the modulation symbol to obtain second soft information, where the second soft information is used to indicate the phase of the phase modulation;

The receiving end obtains the soft information based on the first soft information and the second soft information.
A signal transmission device, characterized in that it comprises:

The processing unit is configured to determine information bits to be sent; perform chirp spread spectrum modulation on the information bits to be sent to obtain a modulated signal; and perform phase compensation on the modulated signal to obtain a signal to be sent. The phase of the signal on two adjacent symbols is continuous;

The transceiver unit is used to send the signal to be sent.
The signal transmission device according to claim 13, wherein in the modulated signal, the initial phase and the end phase of the modulated signal on the first symbol are
Where i represents the cyclic shift value of the modulated signal on the first symbol based on the base signal of the chirp spread spectrum signal, B represents the frequency sweep range, T represents the length of the first symbol, and i is an integer greater than 0, Both B and T are greater than 0;

The processing unit is specifically used for:

Multiply the modulated signal on the first symbol by
Obtain the signal to be sent on the first symbol.
The signal transmission device according to claim 13 or 14, wherein the processing unit is specifically configured to:

Before performing spread spectrum modulation on the information bits to be sent, perform convolutional code encoding on the information bits to be sent to obtain coded bits;

Perform chirp spread spectrum modulation on the coded bits to obtain the modulation symbol.
A signal transmission device, characterized in that it comprises:

Processing unit: used to determine the information bits to be sent; and, perform chirp spread spectrum modulation and phase modulation on the information bits to be sent to obtain a modulated signal;

Transceiving unit: used to send the modulated signal.
The signal transmission device according to claim 16, wherein the processing unit is specifically configured to:

Performing chirp spread spectrum modulation on the information bits to be sent to obtain a first-level modulated signal;

Perform phase modulation on the primary modulation signal to obtain the modulation signal.
The signal transmission device according to claim 16, wherein in the modulated signal, the modulated signal on the first symbol is

(s i )′=s i ×e φ ;

Wherein, s i represents the primary modulation signal on the first symbol, i represents the cyclic shift value of the primary modulation signal on the first symbol based on the chirp spread signal, and φ represents the phase modulation的相。 The phase.
The signal transmission device according to any one of claims 16 to 18, wherein the processing unit is specifically configured to:

Before performing chirp spread spectrum modulation and phase modulation on the information bits to be sent, performing convolutional code encoding on the information bits to be sent to obtain coded bits;

Performing chirp spread spectrum modulation and phase modulation on the coded bits to obtain the modulation symbol.
A signal transmission device, characterized in that it comprises:

The transceiver unit is configured to receive a modulated signal, where the modulated signal is generated by chirp spread spectrum modulation on coded bits obtained through convolutional code encoding;

The processing unit is configured to demodulate the modulated signal to obtain soft information; and, based on the soft information, perform convolutional decoding to obtain information bits.
The signal transmission device according to claim 20, wherein the soft information is determined based on incoherent demodulation and log-likelihood ratio (LLR).
The signal transmission device according to claim 21, wherein for the value b k of the k-th bit, the soft information satisfies the following formula:

Among them, k∈[1,2,…,log 2 M], i∈{0,…,M-1},
Indicates the set of symbols whose value is χ of the k-th information bit, χ is valued as 0 or 1, and s i represents the modulated signal on symbol i,
Indicates that the symbol corresponding to s i belongs to the set
I 0 is the Bessel function, σ 2 is the energy of the noise,
γ i =<s j e jφ +n, s i >, i represents the cyclic shift value of the base signal of the chirp spreading signal based on the first symbol, and s j represents the modulation corresponding to the symbol sent by the receiving end assuming that the sending end Signal, M=B×T, B represents the frequency sweep range, T represents the length of the symbol i, i is an integer greater than 0, and both B and T are greater than 0.
The signal transmission device according to claim 20 or 21, wherein the modulation symbol has also undergone phase modulation, and the modulation signal corresponding to the symbol i is:

(s i )′=s i ×e φ ;

Wherein, s i represents the primary modulation signal corresponding to the symbol i, i represents the cyclic shift value of the base signal of the symbol i based on the chirp spread spectrum signal, and φ represents the phase of the phase modulation.
The signal transmission device according to claim 23, wherein the processing unit is specifically configured to:

Performing one-level demodulation on the modulation symbol to obtain first soft information, where the first soft information is used to indicate the cyclic shift value of the base signal of the modulation symbol based on the chirp spread signal;

Performing secondary demodulation on the modulation symbol to obtain second soft information, where the second soft information is used to indicate the phase of the phase modulation;

Obtain the soft information based on the first soft information and the second soft information.
A signal transmission device, characterized by comprising: a processor, the processor is coupled with a memory, the memory is used to store a program or instruction, when the program or instruction is executed by the processor, the The wireless positioning device executes the method described in any one of claims 1-12.
A computer-readable storage medium for storing a computer program, wherein the computer program includes instructions for implementing the method according to any one of claims 1 to 12.
A computer program product, the computer program product including computer program code, characterized in that, when the computer program code runs on a computer, the computer realizes the method according to any one of claims 1 to 12.