Decoding method, device and readable storage medium

Abstract

The application discloses a decoding method, device and readable storage medium, and belongs to the technical field of communication. The method comprises the following steps: a decoding end determines a coding coefficient vector according to a received signal and a new space-time block code (NSTBC) codebook; the decoding end determines the power sum of the sending symbols on the sending antenna in the first two symbol periods according to the received signal; and the decoding end decodes original coding input symbols in a current symbol period according to the coding coefficient vector, a differential space-time block code (DSTBC) coding mode, the NSTBC codebook and the power sum of the sending symbols on the sending antenna in the first two symbol periods, wherein the first two symbol periods are two adjacent symbol periods before the current symbol period.

Description

Technical Field

[0001] This application belongs to the field of communication technology, specifically relating to a decoding method, device, and readable storage medium. Background Technology

[0002] Traditional codebooks, including Alamouti codes, such as Orthogonal Space-Time Block Code (OSTBC), can achieve full diversity gain and full data rate. However, they are designed for traditional active radio frequency communication and do not take into account the modulation characteristics and implementation complexity of passive terminals such as backscatter communication. At the same time, they require the decoder to know the channel state information (CSI) between all transmitting and receiving antennas.

[0003] Traditional differential space-time block codes are only applicable to constant-mode modulations such as Multiple Phase Shift Keying (MPSK). For non-constant-mode modulations such as Amplitude Phase Shift Keying (APSK) and Quadrature Amplitude Modulation (QAM), the encoding and decoding methods of traditional differential space-time block codes cannot be directly applied because the energies of the constellation symbols are different.

[0004] There is an urgent need for a decoding method that does not require the decoder to know all the CSIs between the transmitting and receiving antennas, reduces the system implementation complexity, and is applicable to differential space-time block codes with non-constant mode modulation. Summary of the Invention

[0005] This application provides a decoding method, device, and readable storage medium that can reduce system implementation complexity and address the issue of applicability to non-constant mode modulation when the decoding end cannot achieve CSI between all transmitting and receiving antennas without knowing the CSI.

[0006] Firstly, a decoding method is provided, including:

[0007] The decoding end determines the coding coefficient vector based on the received signal and the new space-time block code NSTBC codebook;

[0008] The decoding end determines the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal;

[0009] The decoding end decodes the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code (DSTBC) encoding method, the NSTBC codebook, and the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods. The previous two symbol periods are the two adjacent symbol periods preceding the current symbol period.

[0010] Secondly, a decoding device is provided, comprising:

[0011] The first determining module is used by the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook;

[0012] The second determining module is used by the decoding end to determine the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal;

[0013] The differential decoding module is used by the decoding end to decode the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code (DSTBC) encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods. The previous two symbol periods are the two adjacent symbol periods preceding the current symbol period.

[0014] Thirdly, a decoding terminal is provided, the terminal including a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the method described in the first aspect.

[0015] Fourthly, a decoding end is provided, including a processor and a communication interface, wherein the processor is used for the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook; the decoding end to determine the sum of the power of the transmitted symbols on the transmit antennas of the previous two symbol periods based on the received signal; the decoding end to decode the original coded input symbol of the current symbol period based on the coding coefficient vector, the DSTBC encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmit antennas of the previous two symbol periods, wherein the previous two symbol periods are the two adjacent symbol periods preceding the current symbol period.

[0016] Fifthly, a readable storage medium is provided, on which a program or instructions are stored, which, when executed by a processor, implement the steps of the method described in the first aspect.

[0017] In a sixth aspect, a chip is provided, the chip including a processor and a communication interface coupled to the processor, the processor being used to run programs or instructions to implement the method as described in the first aspect.

[0018] In a seventh aspect, a computer program / program product is provided, the computer program / program product being stored in a storage medium, the computer program / program product being executed by at least one processor to perform the steps of the method as described in the first aspect.

[0019] In this embodiment, on the one hand, a signal vector is constructed and a coding coefficient vector is calculated based on the received signal and the NSTBC codebook structure; on the other hand, based on the received signal, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is determined. Then, based on the calculated coding coefficient vector, the DSTBC decoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods, the original coded input symbol of the current symbol period is calculated and recovered. Based on this decoding method, the original symbol can be recovered without pilots, reducing system overhead; when decoding the original coded input symbol of the current symbol period, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is used, making it applicable to non-constant mode modulation; at the same time, based on the NSTBC codebook, while ensuring diversity gain, the number or types of load impedances on each antenna can be reduced, and the probability of detection errors can be effectively reduced. Attached Figure Description

[0020] Figure 1a This is a schematic diagram of the backscatter communication transmitter.

[0021] Figure 1b This is a schematic diagram of Alamouti space-time block code diversity transmission;

[0022] Figure 2 This is a flowchart illustrating the decoding method provided in an embodiment of this application;

[0023] Figure 3 This is a schematic diagram of the decoding device provided in the embodiments of this application;

[0024] Figure 4 This is a schematic diagram of the structure of the communication device provided in the embodiments of this application;

[0025] Figure 5 This is a schematic diagram of the terminal structure provided in the embodiments of this application;

[0026] Figure 6 This is a schematic diagram of the network-side device provided in the embodiments of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0028] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0029] It is worth noting that the technologies described in this application are not limited to Long Term Evolution (LTE) / LTE-Advanced (LTE-A) systems, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency Division Multiple Access (SC-FDMA), and other systems. The terms "system" and "network" in this application are often used interchangeably, and the described technologies can be used with the systems and radio technologies mentioned above, as well as with other systems and radio technologies. The following description describes New Radio (NR) systems for illustrative purposes, and NR terminology is used in most of the following description; however, these technologies can also be applied to applications beyond NR systems, such as 6th generation (6G) radio systems. th Generation 6G communication system.

[0030] In this embodiment, the decoding end can be deployed on the receiving device, such as a terminal or network-side device. The terminal can be a mobile phone, tablet computer, laptop computer, personal digital assistant (PDA), handheld computer, netbook, ultra-mobile personal computer (UMPC), mobile internet device (MID), augmented reality (AR) / virtual reality (VR) device, robot, wearable device, vehicle-mounted device (VUE), pedestrian terminal (PUE), smart home (home devices with wireless communication capabilities, such as refrigerators, televisions, washing machines, or furniture), game console, personal computer (PC), ATM, or self-service machine, etc. Wearable devices include: smartwatches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart chains, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. It should be noted that the specific type of terminal is not limited in the embodiments of this application. Network-side equipment may include access network equipment or core network equipment. Access network equipment may also be referred to as radio access network equipment, radio access network (RAN), radio access network function, or radio access network unit. Access network equipment may include base stations, WLAN access points, or WiFi nodes, etc. Base stations may be referred to as Node B, evolved Node B (eNB), access point, base transceiver station (BTS), radio base station, radio transceiver, basic service set (BSS), extended service set (ESS), home B node, home evolved B node, transmitting and receiving point (TRP), or any other suitable term in the field, as long as the same technical effect is achieved. The base station is not limited to specific technical terms. It should be noted that the embodiments of this application only use base stations in NR systems as examples for introduction and do not limit the specific type of base station.Core network equipment may include, but is not limited to, at least one of the following: core network node, core network function, Mobility Management Entity (MME), Access and Mobility Management Function (AMF), Session Management Function (SMF), User Plane Function (UPF), Policy Control Function (PCF), Policy and Charging Rules Function (PCRF), Edge Application Server Discovery Function (EASDF), Unified Data Management (UDM), Unified Data Repository (UDR), Home Subscriber Server (HSS), Centralized network configuration (CNC), Network Repository Function (NRF), Network Exposure Function (NEF), Local NEF (or L-NEF), and Binding Support. Core network functions (BSF), application functions (AF), etc. It should be noted that this application embodiment only uses core network equipment in the NR system as an example for description, and does not limit the specific type of core network equipment.

[0031] To better understand the technical solution of this application, the following content will be introduced first:

[0032] Future 6G communication networks will need to support massive Internet of Things (IoT) connections, with the number of IoT devices reaching hundreds of billions. The connection density will be 10-100 times higher than 5G, reaching 10-100 devices per square meter. 2The sheer number of IoT devices presents new challenges to both cost and power consumption. Cellular networking, low cost, low power consumption, and even zero-power passive operation are the main trends in the future development of IoT devices. Traditional passive terminals are limited by their power consumption and hardware capabilities, with communication transmission distances mostly below 10 meters, far from achieving the 100-meter coverage target of cellular networking. Therefore, how to effectively improve the communication distance of passive terminals has become a key challenge to be addressed after the cellular networking of this technology.

[0033] Since backscatter communication (BSC) controls the amplitude or phase of a signal by changing the load impedance, and considering other non-ideal factors in the backscatter communication modulation circuit, the amplitude or phase of the output signal will inevitably have some error. However, as long as these signal errors are within a resolvable range, they have little impact on signal demodulation. Therefore, the fewer the number or types of load impedances that need to be controlled on each antenna, the greater the tolerable error and the lower the probability of false detection. Furthermore, due to the power consumption and capability limitations of backscatter communication equipment (BSC UE), in some cases it is undesirable to waste power and resources by transmitting pilot signals; that is, the decoding end should be able to complete signal demodulation without knowing CSI information.

[0034] Backscatter Communication (BSC)

[0035] Backscatter communication refers to the transmission of information by backscatter communication devices using radio frequency signals from other devices or the environment for signal modulation. Its modulation circuitry includes... Figure 1a As shown, backscatter communication devices control the reflection coefficient Γ of the circuit by adjusting its internal impedance, thereby changing the amplitude, frequency, and phase of the incident signal to achieve signal modulation. The signal reflection coefficient can be characterized as:

[0036]

[0037] Where Z0 is the characteristic impedance of the antenna, Z1 is the load impedance, j represents a complex number, and θ T This represents the phase. Assume the incident signal is S. in (t), then the output signal is Therefore, by reasonably controlling the reflection coefficient, corresponding amplitude modulation, frequency modulation, or phase modulation can be achieved. Based on this, backscatter communication devices can be tags in traditional Radio Frequency Identification (RFID) or passive / semi-passive Internet of Things (IoT) devices. For convenience, they are collectively referred to here as BSC UE.

[0038] Constant mode modulation and nonconstant mode modulation

[0039] Typical modulation techniques can be divided into constant-mode modulation and non-constant-mode modulation. Constant-mode modulation means that the power or amplitude of the modulated symbol constellation points is the same; MPSK is a typical example of constant-mode modulation. Non-constant-mode modulation, on the other hand, means that the power or amplitude of the modulated symbol constellation points is not the same; typical non-constant-mode modulation techniques include APSK and QAM.

[0040] Because typical constant-mode modulation (MPSK) only distinguishes constellation points in the phase dimension, the Euclidean distance between constellation points is relatively small, making it susceptible to noise interference. In contrast, non-constant-mode modulations such as APSK or QAM extend the constellation points to a two-dimensional space of amplitude and phase, increasing the Euclidean distance between constellation points and thus providing stronger noise and interference immunity. Table 1 shows the SNR difference between MPSK and MQAM modulation at the same bandwidth efficiency or modulation order. As can be seen from the table, at a certain bit error rate (BER) performance, 64PSK requires an additional 9.95 dB SNR compared to 64QAM to achieve the same BER performance.

[0041] Table 1

[0042] Modulation order M (bits / channels) SNR increment 8(3) 1.65dB 16(4) 4.2dB 32(5) 7.02dB 64(6) 9.95dB

[0043] Orthogonal Space-Time Block Code (OSTBC)

[0044] Space-Time Block Code (STBC) is widely used in cellular communications and wireless local area networks. STBC achieves diversity gain and antenna gain without increasing bandwidth by introducing signal redundancy in the spatial and temporal domains and by constructing a reasonable block coding transmission matrix.

[0045] OSTBC is a special type of linear STBC whose linear space-time block code S satisfies the following single condition:

[0046]

[0047] Where I represents an identity matrix of dimension M, i represents the i-th element of the M-dimensional matrix, and s i These are diagonal elements. The element in the i-th row of S represents the symbol transmitted on the i-th transmitting antenna during M time intervals, and the element in the j-th column of S represents the symbol transmitted on the n-th transmitting antenna. t The symbol transmitted on the root antenna at time j. Each column of the transmission matrix S, satisfying the above formula, is mutually orthogonal. This means that the transmitted signal sequences on different antennas are also orthogonal, ensuring that the STBC can achieve full diversity gain simultaneously. The corresponding decoding end only needs to perform simple maximum ratio combining (MRC) to sequentially decouple the transmitted symbols on different antennas, and then use the maximum likelihood (ML) algorithm for detection and estimation.

[0048] Alamouti codes are the most representative OSTCB codes and can achieve full diversity and full rate gain. For example... Figure 1b The diagram shows the principle of Alamouti codes. Within a given symbol period, two symbols are transmitted simultaneously on two antennas. Assume that in the current symbol period, the symbol transmitted on antenna 1 is denoted as s1, and the symbol transmitted on antenna 2 is denoted as s2. However, in the next symbol period, the symbol transmitted on antenna 1 is... The symbol transmitted on antenna 2 is This results in the following space-time block code matrix:

[0049]

[0050] Suppose the channels from the two transmit antennas to the receive antenna are denoted as h1 and h2, respectively, and satisfy the time-invariant property within two adjacent symbol periods, that is:

[0051]

[0052]

[0053] Therefore, the received signal on the receiving antenna over two symbol periods is:

[0054] r1 = r(t) = h1s1 + h2s2 + n1;

[0055]

[0056] Where n1 and n2 represent received noise and signal interference. The decoding end performs combined reception according to the following criteria:

[0057]

[0058]

[0059] Substituting the received signals r1 and r2, we get:

[0060]

[0061]

[0062] Finally, the signals s1 and s2 can be estimated using the ML detector.

[0063] In addition to the typical Alamouti block code, the codebook of a typical two-antenna OSTBC code is shown in Table 1.

[0064] Table 1

[0065]

[0066] New Space-Time Block Code (NSTBC)

[0067] In recent years, with the deepening of research on backscatter communication, some researchers have proposed the concept of backscatter diversity and designed corresponding space-time block codes. These codes reduce the complexity of hardware implementation and the probability of detection errors by optimizing the codebook of traditional Alamouti codes.

[0068] Taking two-antenna transmit diversity as an example, where the codeword matrix S has a dimension of 2×2, its encoding structure is as follows:

[0069]

[0070] Based on the above coding structure, assuming that in the current symbol period, the symbol transmitted on antenna 1 is denoted as s1, and the symbol transmitted on antenna 2 is denoted as s2... However, in the next symbol period, the symbol transmitted on antenna 1 is s2, while the symbol transmitted on antenna 2 is... According to the OSTBC codeword definition, S2 belongs to the OSTBC codeword category, and therefore can achieve full diversity gain and full-rate transmission. The following analysis examines the differences between this type of codeword and the traditional Alamouti code in backscatter communication.

[0071] Assuming transmission is based on BPSK modulation symbols, according to the backscatter communication mapping principle, the mapping rule between symbols 0 and 1 and the reflection coefficient is as follows:

[0072]

[0073] Symbols 0 and 1 are characterized by controlling two load impedances with reversed phases. Therefore, Table 5 shows the encoding table for diversity coding codeword S2 when transmitting different symbols simultaneously on both antennas. For comparison, Tables 3 and 4 also provide encoding tables for Alamouti codewords and extended Alamouti codewords when transmitting different symbols simultaneously on both antennas. The extended Alamouti codeword is as follows:

[0074]

[0075] Table 3

[0076] 00 Antenna 1 Antenna 2 01 Antenna 1 Antenna 2 t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e -jθ ]]> t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e -j(θ+π) <!-- 6 -->]]> t+T <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e -j(θ+π) ]]> t+T <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e -j(θ+π) ]]> 10 Antenna 1 Antenna 2 11 Antenna 1 Antenna 2 t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e -jθ ]]> t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e -j(θ+π) ]]> t+T <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e -jθ ]]> t+T <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e -jθ ]]>

[0077] Table 4

[0078] 00 Antenna 1 Antenna 2 01 Antenna 1 Antenna 2 t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e jθ ]]> t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e j(θ+π) ]]> t+T <![CDATA[|Γ|e -j(θ+π) ]]> <![CDATA[|Γ|e -jθ ]]> t+T <![CDATA[|Γ|e -jθ ]]> <![CDATA[|Γ|e -jθ ]]> 10 Antenna 1 Antenna 2 11 Antenna 1 Antenna 2 t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e jθ ]]> t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e j(θ+π) ]]> t+T <![CDATA[|Γ|e -j(θ+π) ]]> <![CDATA[|Γ|e -j(θ+π) ]]> t+T <![CDATA[|Γ|e -jθ ]]> <![CDATA[|Γ|e -j(θ+π) ]]>

[0079] Table 5

[0080] 00 Antenna 1 Antenna 2 01 Antenna 1 Antenna 2 t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e jθ ]]> t <![CDATA[|Γ|e jθ ]]> <![CDATA[|Γ|e j(θ+π) ]]> t+T <![CDATA[|Γ|e -jθ ]]> <![CDATA[|Γ|e -j(θ+π) ]]> t+T <![CDATA[|Γ|e -j(θ+π) ]]> <![CDATA[|Γ|e -j(θ+π) ]]> 10 Antenna 1 Antenna 2 11 Antenna 1 Antenna 2 t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e jθ ]]> t <![CDATA[|Γ|e j(θ+π) ]]> <![CDATA[|Γ|e j(θ+π) ]]> t+T <![CDATA[|Γ|e -jθ ]]> <![CDATA[|Γ|e -jθ ]]> t+T <![CDATA[|Γ|e -j(θ+π) ]]> <![CDATA[|Γ|e -jθ ]]>

[0081] As shown in Table 3, based on the codebook designed using NSTBC, antenna 1 only requires two coefficients |Γ|e jθ and |Γ|e j (θ+π) Antenna 2 also only requires two coefficients |Γ|e -jθ and |Γ|e -j(θ+π) This means that only two load impedances are needed for each antenna. According to Table 4-5, based on the Alamouti codeword and the extended Alamouti codeword, antenna 1 and antenna 2 both require four coefficients |Γ|e. jθ ,|Γ|e j(θ+π) ,|Γ|e -jθ ,|Γ|e -j(θ+π) This means that each antenna requires four different load impedances. The same method can be extended to scenarios with four or more antennas.

[0082] Differential Space-Time Block Code (DSTBC)

[0083] For traditional OSTBC and NSTBC, the decoding end uses a coherent detection decoding scheme, thus requiring the transmitting antenna to the receiving antenna to obtain accurate Channel State Information (CSI). However, in high-speed mobile scenarios, scenarios with rapidly changing channel fading conditions, or scenarios where transmitting pilots is difficult due to power limitations in backscatter communication, the decoding end struggles to perform accurate channel estimation, or the cost of accurate channel estimation is very high. In these situations, the decoding end cannot obtain the required CSI information. Differential space-time block coding is a scheme where neither the encoder nor the decoder needs to know the CSI information, the encoding and decoding are simple, and diversity gain can be obtained. The following explanation uses two-antenna transmission and single-antenna reception as examples.

[0084] At the transmitting encoding end, assuming the following symbols are transmitted according to the Alamouti scheme at the encoding ends of symbol period 1 and symbol period 2:

[0085]

[0086] The two transmitted signals s1 and s2 do not carry any information; they are merely reference signals. The encoding end then uses differential coding for transmission. Assume that in 2t-1 symbol periods, the symbols transmitted from the first and second antennas are s1 and s2, respectively. 2t-1 and s 2t Then, in 2t symbol periods, the symbols transmitted from the first antenna and the second antenna are respectively and In 2t+1 symbol cycles, a set of 2m bits arrives at the encoding end, generating the corresponding encoding coefficient vector. The encoder uses the symbol vector sent in the previous two symbol periods and the current coding coefficient vector. Calculate the symbols transmitted in the current 2t+1 symbol period:

[0087]

[0088] Simultaneously, based on the Alamouti codebook, the transmitted symbols on the two antennas in the 2t+2th symbol period are calculated as follows: and Among them, the coding coefficient vector satisfy:

[0089]

[0090]

[0091] The symbols are repeatedly encoded and sent according to the above encoding rules.

[0092] At the receiving and decoding end, assuming signal r2t-1 ,r 2t ,r 2t+1 ,r 2t+2 Received, the channel matrix is ​​defined as follows:

[0093]

[0094] The noise signal is:

[0095]

[0096] The received signal can then be represented as:

[0097]

[0098]

[0099] Therefore, we have:

[0100]

[0101] After merging, we get:

[0102]

[0103] For simplicity, the definition is as follows:

[0104]

[0105]

[0106] Therefore, we can conclude that:

[0107]

[0108] Based on the previous mathematical derivation, we have:

[0109]

[0110] Therefore:

[0111]

[0112] in,

[0113] The signals at the four time points are processed as follows:

[0114]

[0115] Expanding, we get:

[0116]

[0117] For simplicity, the definition is as follows:

[0118]

[0119]

[0120] We can obtain:

[0121]

[0122] Combining the previous mathematical derivations, we have:

[0123]

[0124] Due to the set of coding coefficient vectors All coding coefficient vectors in the vector are of equal length and There is a one-to-one correspondence between the input symbol information and the receiver selects the decision and statistical signal vector. European style closest

[0125] Calculated Then, it is reverse-mapped back to the original symbol to recover the original bit.

[0126] Traditional OSTBC-type codebooks, including Alamouti, can achieve full diversity gain and full data rate, but they are designed for traditional active radio frequency communication and do not take into account the modulation characteristics and implementation complexity of passive terminals such as backscatter communication. At the same time, the receiver is required to know the channel state information (CSI) between all transmitting and receiving antennas.

[0127] The novel space-time block codebook NSTBC proposed for backscatter communication reduces hardware implementation complexity and detection error probability by optimizing the traditional Alamouti codebook. However, this approach requires the receiver to know the CSI information between all transmit and receive antennas. Differential space-time block codes do not require knowledge of the CSI information between all transmit and receive antennas, but they do not consider the modulation characteristics and implementation complexity of passive terminals such as backscatter communication.

[0128] Furthermore, traditional differential space-time block codes are only applicable to constant-mode modulation such as MPSK. For non-constant-mode modulation such as APSK and QAM, the encoding and decoding methods of traditional differential space-time block codes cannot be directly applied because the energy of each constellation symbol is different. However, considering the constellation shaping gain brought by non-constant-mode modulation compared to constant-mode modulation, as well as the difference in amplitude modulation and phase modulation capabilities in backscatter communication, it is necessary to solve the encoding and decoding problem of differential space-time block codes based on non-constant-mode modulation.

[0129] The decoding method provided in this application will be described in detail below with reference to the accompanying drawings and through some embodiments and application scenarios.

[0130] See Figure 2 This application provides a decoding method, wherein the executing entity of the method is a decoding end, which can be a terminal device or a network-side device, and the method includes:

[0131] Step 201: The decoding end determines the coding coefficient vector based on the received signal and the NSTBC codebook;

[0132] Step 202: The decoding end determines the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal;

[0133] Step 203: The decoding end decodes the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code (DSTBC) encoding method, the NSTBC codebook, and the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods.

[0134] The first two symbol periods mentioned above are the two adjacent symbol periods preceding the current symbol period.

[0135] In this embodiment, on the one hand, a signal vector is constructed and a coding coefficient vector is calculated based on the received signal and the NSTBC codebook structure; on the other hand, based on the received signal, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is determined. Then, based on the calculated coding coefficient vector, the DSTBC decoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods, the original coded input symbol of the current symbol period is calculated and recovered. Based on this decoding method, the original symbol can be recovered without pilots, reducing system overhead; when decoding the original coded input symbol of the current symbol period, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is used for normalization, making it applicable to non-constant mode modulation; at the same time, based on the NSTBC codebook, while ensuring diversity gain, the number or types of load impedances on each antenna can be reduced, and the probability of detection errors can be effectively reduced.

[0136] The decoding method provided in this application combines the DSTBC decoding method with the NSTBC codebook, extracting the advantages of both. Furthermore, when decoding the original encoded input symbol of the current symbol period, the power of the transmitted symbols on the transmitting antenna of the previous two symbol periods is normalized to make it suitable for non-constant mode modulation. This novel decoding method can be called the differential NSTBC decoding method under non-constant mode modulation.

[0137] It should be noted that the above signal vector can also be called a statistical signal vector. The above original encoded input symbol refers to the symbol that has been encoded at the encoding end and has not yet been subjected to channel gain and / or noise. It is different from the signal directly received at the decoding end and is a symbol that needs to be decoded by the decoding end.

[0138] Before introducing the decoding scheme of Differential NSTBC in detail, let's first give a brief overview of the encoding process of Differential NSTBC, which is as follows:

[0139] (1) The encoder transmits symbols on the two antennas based on the previous two symbol periods, namely the 2t-1 and 2t symbol periods, and the current coding coefficient vector. Calculate the symbols transmitted on both antennas at the current time, which is the (2t+1)th symbol period:

[0140]

[0141] (2) During the 2t+2 symbol period, the symbols transmitted on both antennas are That is, in the 2t+1 symbol period and the 2t+2 symbol period, the symbols on the two transmit antennas satisfy the NSTBC codebook structure:

[0142]

[0143] Among them, s 2t+1 and For the transmitted symbols on the two transmit antennas obtained by the encoding end in the 2t+1 symbol period, s 2t+2 and The symbols transmitted on the two transmit antennas are obtained by the encoding end in the (2t+2)th symbol period; where the symbols are... For the symbol s 2t+2 conjugate, symbol For the symbol s 2t+1 The negative conjugate of ; the 2t+1th symbol period is the current symbol period, and the 2t+2nd symbol period is the next symbol period of the current symbol period.

[0144] That is, where s 2t+1 and For the first Constellation symbols transmitted on two antennas for one symbol period; s 2t+2 and For the constellation symbols transmitted on two antennas in the 2t+2 symbol period.

[0145] (3) The coding coefficient vector of the (2t+1)th symbol period satisfy:

[0146]

[0147]

[0148] (4) The reference symbol transmitted on both antennas during the first and second symbol periods is... and The symbols on both transmitting antennas also satisfy the NSTBC codebook structure:

[0149]

[0150] Where s1 and s2 are constellation symbols for non-constant mode modulation such as APSK.

[0151] Another implementation scheme could be:

[0152] (1) The encoder transmits symbols on the two antennas based on the previous two symbol periods, namely the 2t-1 and 2t symbol periods, and the current coding coefficient vector. Calculate the symbols transmitted on both antennas at the current time, which is the (2t+1)th symbol period:

[0153]

[0154] (2) During the 2t+2 symbol period, the symbols transmitted on both antennas are That is, in the 2t+1 symbol period and the 2t+2 symbol period, the symbols on the two transmit antennas satisfy the NSTBC codebook structure:

[0155]

[0156] Among them, s 2t+1 and The constellation symbols transmitted on both antennas during the 2t-1th symbol period; s 2t+2 and Let be the constellation symbols transmitted on both antennas during the 2t-th symbol period.

[0157] (3) The coding coefficient vector of the (2t+1)th symbol period satisfy:

[0158]

[0159]

[0160] (4) The reference symbol transmitted on both antennas during the first and second symbol periods is... and The symbols on both transmitting antennas also satisfy the NSTBC codebook structure:

[0161]

[0162] Where s1 and s2 are constellation symbols for non-constant mode modulation such as APSK.

[0163] In a specific implementation, the codebook structure of the NSTBC codebook satisfies:

[0164]

[0165] Among them, s 2t+1 and The transmitted symbols on the two transmit antennas are encoded by the encoding end in the 2t+1 symbol period (it should be noted that the transmitted symbols can also be called constellation symbols, constellation points, etc., and this application embodiment does not specifically limit the name), s 2t+2 and The symbols transmitted on the two transmit antennas are obtained by the encoding end in the (2t+2)th symbol period; where the symbols are... For the symbol s 2t+2 conjugate, symbol For the symbol s 2t+1 The negative conjugate of ; the 2t+1th symbol period is the current symbol period, and the 2t+2nd symbol period is the next symbol period of the current symbol period.

[0166] In a specific implementation, the codebook structure of the NSTBC codebook satisfies:

[0167]

[0168] Among them, s 2t+1 and For the original encoded input symbol of the 2t+1th symbol period decoded by the decoder, s 2t+2 and The original encoded input symbol for the (2t+2)th symbol period decoded by the decoder; where the symbol For the symbol s 2t+2 conjugate, symbol For the symbol s 2t+1 The negative conjugate of ; the 2t+1th symbol period is the current symbol period, and the 2t+2nd symbol period is the next symbol period of the current symbol period.

[0169] In a specific implementation, the decoding end determines the coding coefficient vector based on the received signal and the novel space-time block code NSTBC codebook.

[0170] (1) The decoding end determines the signal vector based on the received signal and the NSTBC codebook;

[0171] (2) The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector;

[0172] Specifically, the decoding end (2) above determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector, including:

[0173] (2.1) The decoding end uses the formula:

[0174]

[0175] Determine the coding coefficient vector at the decoding end in the 2t+1 symbol period.

[0176] in, It is a set of encoding coefficient vectors. For signal vectors, This is the coding coefficient vector determined by the decoder in the 2t+1 symbol period.

[0177] It should be noted that the set of encoding coefficient vectors All coding coefficient vectors in the vector are of equal length and There is a one-to-one correspondence between the input symbols and the signal vector. The decoding end selects the corresponding signal vector according to the above formula. The closest encoding coefficient vector by Euclidean distance As the decision output, it is generally estimated using the maximum likelihood algorithm.

[0178] Specifically, regarding the decoding end decoding the original encoded input symbol of the current symbol period based on the aforementioned encoding coefficient vector, DSTBC encoding method, NSTBC codebook, and the power sum of the transmitted symbols on the transmitting antennas of the previous two symbol periods, this application provides two implementation methods, including:

[0179] Implementation Method 1:

[0180] The decoding end uses the formula:

[0181]

[0182] Decode the original encoded input symbol in the 2t+1 symbol period.

[0183] Among them, s 2t-1 and For the original encoded input symbol of the 2t-1th symbol period decoded by the decoding end, s 2t and For the original encoded input symbol of the 2t-th symbol period decoded by the decoding end, |s 2t-1 | 2 +|s 2t | 2This is the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0184] In a specific implementation, the decoding end determines the sum of the power of the transmitted symbols on the transmitting antennas for the first two symbol periods based on the received signal, including:

[0185] The decoder determines the power of the transmitted symbol on the transmit antenna and |s| for the first two symbol periods using the following formula. 2t-1 | 2 +|s 2t | 2 :

[0186]

[0187]

[0188]

[0189] R = α1S1 + α2S2 + W;

[0190]

[0191]

[0192] W = [w1, w2, ..., w L ] T ;

[0193] in, for autocorrelation, Let be the received signal vector in the 2t-1th symbol period. Let R be the noise vector, R be the signal received at the decoding end from the two transmit antennas at the encoding end after passing through the channel and noise, α1 and α2 be the channel gains from the two transmit antennas encoded at the encoding end to the receive antenna at the decoding end, Λ(α1,α2) be the channel matrix, and r be the noise vector. 2t-1 and For the signal received by the decoding end in the 2t-1 symbol period, η 2t-1 and Let S1 and S2 be the received noise at the decoding end in the 2t-1 symbol period, respectively, and let W be the symbol vector of dimension L from the two transmit antennas after encoding at the encoding end to the receive antenna at the decoding end.

[0194] Specifically, the symbolic power |s 2t-1 | 2 +|s 2t | 2 The transmitted symbols from the two antennas during the demodulated 2t-1 symbol period can be obtained. Calculated; or, symbolic power |s 2t-1 | 2 +|s 2t | 2 The received signal vector can be calculated. The product of its own self-conjugate matrix (Hermitian) is calculated as follows:

[0195]

[0196] in, Λ(α1,α2) is the vector of the received signal; Λ(α1,α2) is the channel matrix.

[0197] The channel power (|α1|) 2 +|α2| 2 This can be obtained through the statistical expectation of the received signal. One possible estimation method is:

[0198]

[0199] in,

[0200] R = α1S1 + α2S2 + W

[0201] Represents the received signal vector; and This represents a symbol vector of dimension L transmitted from the first and second antennas; W = [w1, w2, ..., w L ] T This is signal noise.

[0202] Implementation Method Two:

[0203] The decoding end uses the formula:

[0204]

[0205] Decode the original encoded input symbol in the 2t+1 symbol period.

[0206] Among them, s 2t-1 and For the original encoded input symbol of the 2t-1th symbol period decoded by the decoding end, s 2t and The original encoded input symbol for the 2t-th symbol period decoded by the decoding end. It is the square root of the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0207] Accordingly, The calculation method can refer to the above implementation method one |s2t-1 | 2 +|s 2t | 2 The calculation process only requires calculating |s 2t-1 | 2 +|s 2t | 2 Then you can proceed with the prescription.

[0208] In a specific implementation, for either Implementation Method 1 or Implementation Method 2 described above, this method further includes:

[0209] The decoding end determines the original bits or original symbols based on... The preset mapping table determines the original bit or original symbol;

[0210] The preset mapping table contains the original bits or original symbols and the coding coefficient vector. The mapping relationship between them.

[0211] In this embodiment, the decoding end uses a direct table lookup method to determine the original bit or original symbol. The advantage of this method is that the original bit or original symbol is recovered by directly querying the mapping table, which reduces the complexity and decoding latency.

[0212] The aforementioned raw bits or raw symbols refer to the initial data bits or initial symbols to be encoded at the encoding end, and the aforementioned initial reference symbol refers to the reference symbol on the transmitting antenna in the initial symbol period, i.e., the first symbol period. In the embodiments of this application, the decoding end performs decoding processing in the above manner, and finally decodes to obtain the initial data bits or initial symbols.

[0213] In a specific implementation, for embodiments one and two described above, this method further includes:

[0214] (1) The decoding end inputs symbols based on the decoded original encoding. Determine the original symbol (s) 2t+1 ,s 2t+2 );

[0215] (2) The decoding end, according to the (s) 2t+1 ,s 2t+2 ), determine the original bits.

[0216] In this embodiment, the decoding end calculates the original bits or original symbols directly. The advantage of this approach is that the decoding end does not need to store a mapping table; instead, it decodes the original encoded input symbols through real-time calculation. It should be noted that...

[0217] In a specific implementation, for the first implementation described above, this method further includes:

[0218] The decoding end determines the original encoded input symbol or initial reference symbol for the first symbol period as... And the original encoded input symbol for the second symbol period is

[0219] The decoding end uses the formula:

[0220]

[0221] Decode the original encoded input symbol for the third symbol period;

[0222] in, This is the encoding coefficient vector obtained by the decoder in the third symbol period. and The following NSTBC codebook is satisfied:

[0223]

[0224] In this way, the decoding end has completed the decoding process for the first two symbol periods. The third symbol period and subsequent symbol periods can then use the same decoding process as the (2t+1)th symbol period.

[0225] In a specific implementation, for the second implementation described above, this method further includes:

[0226] The decoding end determines the original encoded input symbol or initial reference symbol for the first symbol period as... And the original encoded input symbol for the second symbol period is

[0227] The decoding end uses the formula:

[0228]

[0229] Decode the original encoded input symbol for the third symbol period;

[0230] in, This is the encoding coefficient vector obtained by the decoder in the third symbol period. and The following NSTBC codebook is satisfied:

[0231]

[0232] In this way, the decoding end has completed the decoding process for the first two symbol periods. The third symbol period and subsequent symbol periods can then use the same decoding process as the (2t+1)th symbol period.

[0233] In a specific implementation, the decoding end determines the signal vector based on the received signal and the NSTBC codebook, including:

[0234] The decoding end uses the formula:

[0235]

[0236]

[0237] Determine the signal vector

[0238] Where, r 2t-1 For the signal received by the decoding end in the 2t-1 symbol period, r 2t For the signal received by the decoding end in the 2t-th symbol period, r 2t+1 For the signal received by the decoding end in the 2t+1 symbol period, r 2t+2 This refers to the signal received by the decoding end during the 2t+2 symbol period.

[0239] Taking the 2t-1 and 2t symbol periods as examples, the received signal is:

[0240]

[0241]

[0242] Where α1 and α2 are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively, and η 2t-1 η represents the received noise at the decoding end during the 2t-1 symbol period. 2t This represents the received noise at the decoding end during the 2t-th symbol period.

[0243] Specifically, signal vector satisfy:

[0244]

[0245]

[0246] in, It is a linear combination vector of the useful signals. This is the noise interference vector, i.e., the signal vector. A linear combination vector of useful signals With noise interference vector It consists of two parts.

[0247] Specifically, satisfy:

[0248]

[0249]

[0250] satisfy:

[0251]

[0252]

[0253] Λ(α1,α2) is the channel matrix, characterized as follows:

[0254]

[0255] N 2t-1 N 2t+1 M 2t Let the noise vectors be represented as follows:

[0256]

[0257]

[0258]

[0259] Where α1 and α2 are the channel gains from the two transmit antennas after encoding at the encoder to the receive antenna at the decoder, respectively. 2t-1 and For the original encoded input symbol decoded by the decoding end in the 2t-1 symbol period, s 2t and For the original encoded input symbol decoded by the decoding end in the 2t-th symbol period, s 2t+1 and For the original encoded input symbol decoded by the decoding end in the 2t+1 symbol period, s 2t+2 and The original encoded input symbol decoded by the decoding end in the 2t+2 symbol period;

[0260] η 2t-1 η represents the received noise at the decoding end during the 2t-1 symbol period. 2t η represents the received noise at the decoding end during the 2t-th symbol period. 2t+1 η represents the received noise at the decoding end during the (2t+1)th symbol period. 2t+2 This represents the received noise at the decoding end during the 2t+2 symbol period.

[0261] The above describes the process by which the decoder decodes the original encoded input symbol of the current symbol period. By repeating the above process, the overall differential NSTBC decoding and transmission can be completed.

[0262] The technical solutions of the embodiments of this application are described below with reference to specific implementation examples:

[0263] Example 1 illustrates this with two transmitting antennas, a single receiving antenna, and APSK modulation.

[0264] (1) Estimating channel power

[0265] Suppose that the receiver receives L symbols over a period of time, as follows:

[0266] R = α1S1 + α2S2 + W

[0267] and W represents a symbol vector of dimension L transmitted from the first and second antennas at the encoding end; W = [η1, η2, ..., η L ] T It is additive Gaussian noise. The expectation of the product of the received signal and its conjugate transpose is:

[0268]

[0269] Therefore, a feasible method for estimating channel power is as follows:

[0270]

[0271] At this point, the symbol length L can satisfy a certain length.

[0272] The above is just one method for estimating channel power, but it is not limited to this.

[0273] (2) Estimate the transmitted signal power

[0274] One implementation method assumes that, in the (2t-1)th symbol period, the received signal vector is:

[0275]

[0276] Then we have:

[0277]

[0278] Where Λ(α1,α2) is the channel matrix. The signal power can be estimated based on the channel power calculated in (1).

[0279] Another implementation method, signal power |s 2t-1 | 2 +|s 2t | 2 The transmitted symbols from the two antennas during the demodulated 2t-1 symbol period can be obtained. Obtained directly by calculation;

[0280] (3) Calculate the statistical signal vector based on the received signal.

[0281] Assume the received signals of the receiving antenna in the 2t-1, 2t, 2t+1, and 2t+2 symbol periods are r, respectively. 2t-1 ,r 2t ,r 2t+1 ,r 2t+2 The channel matrix is ​​defined as follows:

[0282]

[0283] The noise vector is:

[0284]

[0285] Then, in the 2t-1 and 2t+1 symbol periods, the received signal vectors are:

[0286]

[0287]

[0288] The received signal vectors in the 2t-1 and 2t+1 symbol periods are processed as follows:

[0289]

[0290] After merging, we get:

[0291]

[0292] For simplicity, we define statistical signal components. Noise interference components and useful signal components They are respectively:

[0293]

[0294]

[0295]

[0296] From this, we can obtain the first statistical signal component. for:

[0297]

[0298] Similarly, define the received signal vector:

[0299]

[0300] Among them, M 2t The noise vector is defined as follows:

[0301]

[0302] The received signal vectors in the 2t-1 and 2t+1 symbol periods are processed as follows.

[0303]

[0304] After merging, we get:

[0305]

[0306] For simplicity, we define statistical signal components. Noise interference components and useful signal components They are respectively:

[0307]

[0308]

[0309]

[0310] This allows us to obtain the second statistical signal component. for:

[0311]

[0312] Therefore, the statistical signal vector of the received signal is calculated:

[0313]

[0314] (4) Calculate the coding coefficient vector

[0315] The decoding end obtains the statistical signal vector of the received signal. Then, the decoder selects the decision and statistical signal vectors. The closest encoding coefficient vector by Euclidean distance As the decoded output:

[0316]

[0317] (5) Decode the original symbol by calculation.

[0318] (a) The decoding end first decodes the transmitted symbols on the two antennas in the third symbol period using differential decoding.

[0319]

[0320] in, The symbols transmitted on both antennas during the first symbol period are known symbols. They also satisfy the NSTBC codebook structure along with the transmitted symbols transmitted on both antennas during the second symbol period.

[0321]

[0322] The coding coefficient vector for the third symbol period is calculated based on (2).

[0323] (b) Assumption The decoded transmitted symbols from the two antennas in the 2t-1th symbol period satisfy the NSTBC codebook structure with the recovered transmitted symbols from the two antennas in the 2tth symbol period:

[0324]

[0325] (c) In the 2t+1th symbol period, the coding coefficient vector of the 2t+1th symbol period is calculated by (2). Then, the transmitted symbols of the two transmitting antennas in the 2t+1th symbol period are decoded using the differential decoding method.

[0326]

[0327] Decode the transmitted symbols from the two antennas in the (2t+1)th symbol period. After that, the original input symbol (s) can be restored. 2t+1 ,s 2t+2 ) and the corresponding input bits.

[0328] (6) Repeat steps (1)-(5) to complete the decoding of all received signals.

[0329] It should be noted that in Example 1, the original bits or original symbols are calculated directly. Alternatively, the coding coefficient vector can be obtained directly by querying a preset mapping table.

[0330] Example 2:

[0331] Unlike Example 1, when obtaining the coding coefficient vector The corresponding input symbol is then obtained through calculation. Example 2 uses a lookup table to decode the original input symbols. The specific solution is as follows:

[0332] (1) Estimate the channel power based on the received signal, as shown in Example 1;

[0333] (2) Calculate the signal power based on the received signal, as shown in Example 1;

[0334] (3) Calculate the statistical signal vector based on the received signal. Please refer to Example 1 for details;

[0335] (4) Calculate the coding coefficient vector Please refer to Example 1 for details;

[0336] (5) The original input symbols / bits are decoded by querying the mapping table between the coding coefficient vector and the input symbols / bits.

[0337] (6) Repeat steps (1)-(5) to complete the decoding of all received signals.

[0338] Let's take APSK as an example to illustrate the differential NSTBC decoding process. Assuming (2,2)-APSK modulation is used, the set of constellation points is {-3,-1,1,3}, and the set of coding coefficient vectors is... Let the two reference modulation signals be s1 = 1 and s2 = 3, and the four input bits at the encoder input be c1c2c3c4. According to the mapping rule "00, 01, 10, 11" → {1, 3, -1, -3}, the first two bits c1c2 are mapped to symbol s3, and the last two bits c3c4 are mapped to symbol s4. The mapping relationship is as follows:

[0339]

[0340]

[0341] According to the definition of the coding coefficient vector, we have

[0342]

[0343]

[0344] Based on the different values ​​of input bits c1 and c2, we can obtain for:

[0345] Table 6: Mapping Table of APSK Input Bits and Coding Coefficient Vectors

[0346]

[0347]

[0348] Because this mapping table includes encoding coefficient vectors under different symbol periods Both are applicable, therefore, when calculating the coding coefficient vector... After obtaining the signal power and channel power, the input symbols or input bits (c1c2, c3c4) can be obtained by looking up the mapping table.

[0349] It is understood that this application may also include an example in which, when decoding the original encoded input symbol of the current symbol period, the square root of the sum of the power of the transmitted symbols on the transmitting antenna of the previous two symbol periods is used, which corresponds to the second implementation method described above. The real-time method two also includes two methods: direct calculation and querying the mapping table.

[0350] The decoding method provided in this application can be executed by a decoding device. This application uses an example of a decoding device executing the decoding method to illustrate the decoding device provided in this application.

[0351] See Figure 3 This application provides a decoding device 300, comprising:

[0352] The first determining module 301 is used by the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook;

[0353] The second determining module 302 is used by the decoding end to determine the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal;

[0354] The differential decoding module 303 is used by the decoding end to decode the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code DSTBC encoding method, the NSTBC codebook, and the power of the transmitted symbols on the transmitting antenna of the previous two symbol periods.

[0355] In this embodiment, on the one hand, a signal vector is constructed and a coding coefficient vector is calculated based on the received signal and the NSTBC codebook structure; on the other hand, based on the received signal, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is determined. Then, based on the calculated coding coefficient vector, the DSTBC decoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods, the original coded input symbol of the current symbol period is calculated and recovered. Based on this decoding method, the original symbol can be recovered without pilots, reducing system overhead; when decoding the original coded input symbol of the current symbol period, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is used for normalization, making it applicable to non-constant mode modulation; at the same time, based on the NSTBC codebook, while ensuring diversity gain, the number or types of load impedances on each antenna can be reduced, and the probability of detection errors can be effectively reduced.

[0356] In a specific implementation, the codebook structure of the NSTBC codebook satisfies:

[0357]

[0358] Wherein, the s 2t+1 and stated The s is the original encoded input symbol of the 2t+1th symbol period decoded by the decoder. 2t+2 and stated The original encoded input symbol for the 2t+2th symbol period decoded by the decoder; wherein the symbol For the symbol s 2t+2 conjugate, symbol For the symbol s 2t+1 The negative conjugate of the symbol; the 2t+1th symbol period is the current symbol period, and the 2t+2th symbol period is the next symbol period of the current symbol period.

[0359] In a specific implementation, the first determining module is specifically used for:

[0360] The decoding end determines the signal vector based on the received signal and the NSTBC codebook;

[0361] The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector.

[0362] In a specific implementation, the first determining module is specifically used for:

[0363] The decoding end is based on the formula:

[0364]

[0365] Determine the coding coefficient vector of the decoding end in the (2t+1)th symbol period.

[0366] Among them, the For the set of encoding coefficient vectors, the For the signal vector, the This is the coding coefficient vector determined by the decoder in the 2t+1 symbol period.

[0367] In a specific implementation, the differential decoding module is specifically used for:

[0368] The decoding end is based on the formula:

[0369]

[0370] Decode the original encoded input symbol in the 2t+1 symbol period;

[0371] Wherein, the s 2t-1 and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, wherein s 2t and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the |s 2t-1 | 2 +|s 2t | 2 This is the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0372] In a specific implementation, the second determining module is specifically used for:

[0373] The decoding end determines the power of the transmitted symbols on the transmitting antenna and |s| for the first two symbol periods according to the following formula. 2t-1 | 2 +|s 2t | 2 :

[0374]

[0375]

[0376]

[0377] R = α1S1 + α2S2 + W;

[0378]

[0379]

[0380] W = [w1, w2, ..., w L ] T ;

[0381] Among them, the for The autocorrelation, the For the received signal vector in the 2t-1th symbol period, the Let R be the noise vector, where R is the signal received by the decoding end from the two transmit antennas of the encoding end after passing through the channel and noise, α1 and α2 are the channel gains from the two transmit antennas encoded at the encoding end to the receive antenna of the decoding end, Λ(α1,α2) is the channel matrix, and r is the noise vector. 2t-1 and For the signal received by the decoding end in the 2t-1 symbol period, η 2t-1 and S1 and S2 are symbol vectors of dimension L from the two transmitting antennas encoded at the encoding end to the receiving antenna at the decoding end, and W is the signal noise.

[0382] In a specific implementation, the differential decoding module can also be used for:

[0383] The decoding end is based on the formula:

[0384]

[0385] Decode the original encoded input symbol in the 2t+1 symbol period;

[0386] Wherein, the s 2t-1 and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, wherein s 2t and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the It is the square root of the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0387] In a specific embodiment, the device further includes:

[0388] The third determining module is used by the decoding end to determine the original bits or original symbols based on the... The preset mapping table determines the original bit or original symbol;

[0389] The preset mapping table contains the original bits or original symbols and the coding coefficient vector. The mapping relationship between them after the initial reference symbol is determined.

[0390] In a specific embodiment, the device further includes:

[0391] The fourth determining module is used by the decoding end to input symbols based on the decoded original encoding. Determine the original symbol (s) 2t+1 ,s 2t+2 );

[0392] The decoding end is based on the (s) 2t+1 ,s 2t+2 ), determine the original bits.

[0393] In a specific embodiment, the device further includes:

[0394] The fifth determining module is used by the decoding end to determine the original encoded input symbol of the first symbol period as... And the original encoded input symbol for the second symbol period is

[0395] The original encoded input symbols This is the initial reference symbol;

[0396] The differential decoding module is also used by the decoding end to perform the following calculation:

[0397]

[0398] Decode the original encoded input symbol for the third symbol period;

[0399] in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied:

[0400]

[0401] In a specific embodiment, the device further includes:

[0402] The fifth determining module is used by the decoding end to determine the original encoded input symbol of the first symbol period as... And the original encoded input symbol for the second symbol period is

[0403] The original encoded input symbols This is the initial reference symbol;

[0404] The differential decoding module is also used by the decoding end to perform the following calculation:

[0405]

[0406] Decode the original encoded input symbol for the third symbol period;

[0407] in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied:

[0408]

[0409] In a specific implementation, the first determining module is specifically used for:

[0410] The decoding end is based on the formula:

[0411]

[0412]

[0413] Determine the signal vector

[0414] Wherein, the r 2t-1 For the signal received by the decoding end in the 2t-1 symbol period, the r 2t The signal received by the decoding end in the 2t symbol period, wherein, r 2t+1 For the signal received by the decoding end in the 2t+1 symbol period, the r 2t+2 This refers to the signal received by the decoding end in the 2t+2 symbol period.

[0415] In a specific implementation, the signal vector satisfy:

[0416]

[0417]

[0418] in, It is a linear combination vector of the useful signals. This is the noise interference vector.

[0419] In a specific implementation, the satisfy:

[0420]

[0421]

[0422] The satisfy:

[0423]

[0424]

[0425]

[0426]

[0427]

[0428]

[0429] Where α1 and α2 are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively, and s 2t-1and stated The s is the original encoded input symbol decoded by the decoding end in the 2t-1 symbol period. 2t and stated The s is the original encoded input symbol decoded by the decoding end in the 2t-th symbol period. 2t+1 and stated The s is the original encoded input symbol decoded by the decoding end in the (2t+1)th symbol period. 2t+2 and stated The original encoded input symbol decoded by the decoding end in the 2t+2 symbol period;

[0430] Λ(α1,α2) is the channel matrix;

[0431] The N 2t-1 The N 2t+1 The M 2t This is the noise vector;

[0432] The η 2t-1 For the received noise at the decoding end in the 2t-1 symbol period, η 2t For the received noise at the decoding end in the 2t-th symbol period, η 2t+1 For the received noise at the decoding end in the 2t+1 symbol period, η 2t+2 This refers to the received noise at the decoding end during the 2t+2 symbol period.

[0433] The decoding device in this application embodiment can be an electronic device, such as an electronic device with an operating system, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal, or other devices besides a terminal. For example, the terminal can include, but is not limited to, the type of terminal 11 listed above; other devices can be servers, network attached storage (NAS), etc., and this application embodiment does not specifically limit the type.

[0434] The decoding device provided in this application embodiment can achieve... Figure 2 The various processes implemented in the method embodiments achieve the same technical effect, and will not be described again here to avoid repetition.

[0435] Optional, such as Figure 4As shown, this application embodiment also provides a communication device 400, including a processor 401 and a memory 402. The memory 402 stores programs or instructions that can run on the processor 401. For example, when the communication device 400 is a terminal, the program or instructions executed by the processor 401 implement the various steps of the above-described decoding device method embodiment and achieve the same technical effect. When the communication device 400 is a network-side device, the program or instructions executed by the processor 401 implement the various steps of the above-described decoding device method embodiment and achieve the same technical effect. To avoid repetition, further details are omitted here.

[0436] This application embodiment also provides a decoding end, including a processor and a communication interface. The processor is used by the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook. The decoding end decodes the original coded input symbol of the current symbol period based on the coding coefficient vector, the DSTBC encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods.

[0437] Specifically, for the case where the decoding end is the terminal, Figure 5 A schematic diagram of the hardware structure of a terminal to implement an embodiment of this application.

[0438] The terminal 500 includes, but is not limited to, at least some of the following components: radio frequency unit 501, network module 502, audio output unit 503, input unit 504, sensor 505, display unit 506, user input unit 507, interface unit 508, memory 509, and processor 510.

[0439] Those skilled in the art will understand that the terminal 500 may also include a power supply (such as a battery) for supplying power to various components. The power supply may be logically connected to the processor 510 through a power management system, thereby enabling functions such as managing charging, discharging, and power consumption through the power management system. Figure 5 The terminal structure shown does not constitute a limitation on the terminal. The terminal may include more or fewer components than shown, or combine certain components, or have different component arrangements, which will not be elaborated here.

[0440] It should be understood that, in this embodiment, the input unit 504 may include a graphics processing unit (GPU) 5041 and a microphone 5042. The GPU 5041 processes image data of still images or videos obtained by an image capture device (such as a camera) in video capture mode or image capture mode. The display unit 506 may include a display panel 5061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 507 includes at least one of a touch panel 5071 and other input devices 5072. The touch panel 5071 is also called a touch screen. The touch panel 5071 may include a touch detection device and a touch controller. Other input devices 5072 may include, but are not limited to, physical keyboards, function keys (such as volume control buttons, power buttons, etc.), trackballs, mice, and joysticks, which will not be described in detail here.

[0441] In this embodiment, after receiving downlink data from the network-side device, the radio frequency unit 501 can transmit it to the processor 510 for processing; in addition, the radio frequency unit 501 can send uplink data to the network-side device. Typically, the radio frequency unit 501 includes, but is not limited to, antennas, amplifiers, transceivers, couplers, low-noise amplifiers, duplexers, etc.

[0442] The memory 509 can be used to store software programs or instructions, as well as various data. The memory 509 may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory 509 may include volatile memory or non-volatile memory, or both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory x09 in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0443] Processor 510 may include one or more processing units; optionally, processor 510 integrates an application processor and a modem processor, wherein the application processor mainly handles operations involving the operating system, user interface, and applications, and the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into processor 510.

[0444] The processor 510 is used by the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook.

[0445] The processor 510 is used by the decoding end to determine the sum of the power of the transmitted symbols on the transmitting antennas in the first two symbol periods based on the received signal;

[0446] The processor 510 is used by the decoding end to decode the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code (DSTBC) encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods.

[0447] In this embodiment, on the one hand, a signal vector is constructed and a coding coefficient vector is calculated based on the received signal and the NSTBC codebook structure; on the other hand, based on the received signal, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is determined, and then the original coded input symbol of the current symbol period is calculated and recovered based on the calculated coding coefficient vector, the DSTBC decoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods. Based on this decoding method, the original symbol can be recovered without pilots, reducing system overhead; when decoding the original coded input symbol of the current symbol period, the sum of the power of the transmitted symbols on the transmit antennas of the first two symbol periods is used for normalization, making it applicable to non-constant mode modulation; simultaneously, based on the NSTBC codebook, while ensuring diversity gain, the number or types of load impedances on each antenna can be reduced, and the probability of detection errors is effectively reduced. In a specific implementation, the codebook structure of the NSTBC codebook satisfies:

[0448]

[0449] Wherein, the s 2t+1 and stated The s is the original encoded input symbol of the 2t+1th symbol period decoded by the decoder. 2t+2 and stated The original encoded input symbol for the 2t+2th symbol period decoded by the decoder; wherein the symbol For the symbol s 2t+2 conjugate, symbol For the symbol s 2t+1 The negative conjugate of the symbol; the 2t+1th symbol period is the current symbol period, and the 2t+2th symbol period is the next symbol period of the current symbol period.

[0450] Specifically, the processor 510 is used for:

[0451] The decoding end determines the signal vector based on the received signal and the NSTBC codebook;

[0452] The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector.

[0453] Specifically, the processor 510 is used for:

[0454] The decoding end is based on the formula:

[0455]

[0456] Determine the coding coefficient vector of the decoding end in the (2t+1)th symbol period.

[0457] Among them, the For the set of encoding coefficient vectors, the For the signal vector, the This is the coding coefficient vector determined by the decoder in the 2t+1 symbol period.

[0458] Specifically, the processor 510 is used for:

[0459] The decoding end is based on the formula:

[0460]

[0461] Decode the original encoded input symbol in the 2t+1 symbol period;

[0462] Wherein, the s 2t-1 and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, wherein s 2t and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the |s 2t-1 | 2 +|s 2t | 2 This is the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0463] Specifically, the processor 510 is used for:

[0464] The decoding end determines the power of the transmitted symbols on the transmitting antenna and |s| for the first two symbol periods according to the following formula. 2t-1 | 2 +|s 2t | 2 :

[0465]

[0466]

[0467]

[0468] R = α1S1 + α2S2 + W;

[0469]

[0470]

[0471] W = [w1, w2, ..., w L ] T ;

[0472] Among them, the for The autocorrelation, the For the received signal vector in the 2t-1th symbol period, the Let R be the noise vector, where R is the signal received by the decoding end from the two transmit antennas of the encoding end after passing through the channel and noise, α1 and α2 are the channel gains from the two transmit antennas encoded at the encoding end to the receive antenna of the decoding end, Λ(α1,α2) is the channel matrix, and r is the noise vector. 2t-1 and For the signal received by the decoding end in the 2t-1 symbol period, η 2t-1 and S1 and S2 are symbol vectors of dimension L from the two transmitting antennas encoded at the encoding end to the receiving antenna at the decoding end, and W is the signal noise.

[0473] Specifically, the processor 510 can also be used for:

[0474] The decoding end is based on the formula:

[0475]

[0476] Decode the original encoded input symbol in the 2t+1 symbol period;

[0477] Wherein, the s 2t-1 and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, wherein s 2t and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the It is the square root of the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

[0478] Specifically, the processor 510 is used for:

[0479] The decoding end determines the original bits or original symbols based on the... The preset mapping table determines the original bit or original symbol;

[0480] The preset mapping table contains the original bits or original symbols and the coding coefficient vector. The mapping relationship between them after the initial reference symbol is determined.

[0481] Specifically, the processor 510 is used for:

[0482] The decoding end inputs symbols based on the decoded original encoded data. Determine the original symbol (s) 2t+1 ,s 2t+2 );

[0483] The decoding end is based on the (s) 2t+1 ,s 2t+2 ), determine the original bits.

[0484] Specifically, the processor 510 is used for:

[0485] The decoding end determines the original encoded input symbol for the first symbol period as... And the original encoded input symbol for the second symbol period is

[0486] The original encoded input symbols This is the initial reference symbol;

[0487] The differential decoding module is also used by the decoding end to perform the following calculation:

[0488]

[0489] Decode the original encoded input symbol for the third symbol period;

[0490] in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied:

[0491]

[0492] Specifically, the processor 510 is used for:

[0493] The decoding end determines the original encoded input symbol for the first symbol period as... And the original encoded input symbol for the second symbol period is

[0494] The original encoded input symbols This is the initial reference symbol;

[0495] The differential decoding module is also used by the decoding end to perform the following calculation:

[0496]

[0497] Decode the original encoded input symbol for the third symbol period;

[0498] in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied:

[0499]

[0500] Specifically, the processor 510 is used for:

[0501] The decoding end is based on the formula:

[0502]

[0503]

[0504] Determine the statistical signal vector

[0505] Wherein, the r 2t-1 For the signal received by the decoding end in the 2t-1 symbol period, the r 2t The signal received by the decoding end in the 2t symbol period, wherein, r 2t+1 For the signal received by the decoding end in the 2t+1 symbol period, the r 2t+2 This refers to the signal received by the decoding end in the 2t+2 symbol period.

[0506] Specifically, the signal vector satisfy:

[0507]

[0508]

[0509] in, It is a linear combination vector of the useful signals. This is the noise interference vector.

[0510] Specifically, the satisfy:

[0511]

[0512]

[0513] The satisfy:

[0514]

[0515]

[0516]

[0517]

[0518]

[0519]

[0520] Where α1 and α2 are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively, and s 2t-1 and stated The s is the original encoded input symbol decoded by the decoding end in the 2t-1 symbol period. 2t and stated The s is the original encoded input symbol decoded by the decoding end in the 2t-th symbol period. 2t+1 and stated The s is the original encoded input symbol decoded by the decoding end in the (2t+1)th symbol period. 2t+2 and stated The original encoded input symbol decoded by the decoding end in the 2t+2 symbol period;

[0521] Λ(α1,α2) is the channel matrix;

[0522] The N 2t-1 The N 2t+1 The M 2t This is the noise vector;

[0523] The η 2t-1 For the received noise at the decoding end in the 2t-1 symbol period, η 2t For the received noise at the decoding end in the 2t-th symbol period, η 2t+1 For the received noise at the decoding end in the 2t+1 symbol period, η 2t+2 This refers to the received noise at the decoding end during the 2t+2 symbol period.

[0524] Specifically, for cases where the decoding end is a network-side device, such as Figure 6As shown, the network-side device 600 includes: an antenna 61, a radio frequency (RF) device 62, a baseband device 63, a processor 64, and a memory 65. The antenna 61 is connected to the RF device 62. In the uplink direction, the RF device 62 receives information through the antenna 61 and transmits the received information to the baseband device 63 for processing. In the downlink direction, the baseband device 63 processes the information to be transmitted and sends it to the RF device 62. The RF device 62 processes the received information and transmits it through the antenna 61.

[0525] The methods described in the above embodiments can be implemented in a baseband device 63, which includes a baseband processor.

[0526] Baseband device 63 may include, for example, at least one baseband board on which multiple chips are disposed, such as Figure 6 As shown, one of the chips is, for example, a baseband processor, which is connected to the memory 65 via a bus interface to call the program in the memory 65 and execute the network device operation shown in the above method embodiment.

[0527] The network-side device may also include a network interface 66, such as a common public radio interface (CPRI).

[0528] Specifically, the network-side device 600 of this embodiment further includes: instructions or programs stored in a memory 65 and executable on a processor 64, wherein the processor 64 calls the instructions or programs in the memory 65 to execute. Figure 3 The methods executed by each module shown achieve the same technical effect, and to avoid repetition, they will not be described in detail here.

[0529] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described decoding method embodiments and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0530] The processor is the processor in the terminal described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk.

[0531] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described decoding method embodiments and achieve the same technical effect. To avoid repetition, it will not be described again here. It should be understood that the chip mentioned in this application embodiment can also be called a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0532] This application also provides a computer program / program product, which is stored in a storage medium and executed by at least one processor to implement the various processes of the above-described decoding method embodiments, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0533] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0534] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0535] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A decoding method, characterized in that, include: The decoding end determines the coding coefficient vector based on the received signal and the new space-time block code NSTBC codebook; The decoding end determines the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal; The decoding end decodes the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code (DSTBC) encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods. The previous two symbol periods are the two adjacent symbol periods preceding the current symbol period. The codebook structure of the NSTBC codebook satisfies: ； Among them, the and stated The original encoded input symbol for the 2t+1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the (2t+2)th symbol period decoded by the decoding end; wherein the symbol For symbols conjugate, symbol For symbols The negative conjugate of the symbol; the 2t+1th symbol period is the current symbol period, and the 2t+2th symbol period is the next symbol period of the current symbol period.

2. The method according to claim 1, characterized in that, The decoding end determines the coding coefficient vector based on the received signal and the NSTBC codebook, including: The decoding end determines the signal vector based on the received signal and the NSTBC codebook; The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector.

3. The method according to claim 2, characterized in that, The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector, including: The decoding end is based on the formula: ； Determine the coding coefficient vector of the decoding end in the (2t+1)th symbol period. ; Among them, the For the set of encoding coefficient vectors, the For the signal vector, the This is the coding coefficient vector determined by the decoder in the 2t+1 symbol period.

4. The method according to claim 3, characterized in that, The decoding end decodes the original encoded input symbol for the current symbol period based on the encoded coefficient vector, the DSTBC encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods, including: The decoding end is based on the formula: ， Decode the original encoded input symbol in the 2t+1 symbol period; Among them, the and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the This is the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

5. The method according to claim 1, characterized in that, The decoding end determines the sum of the power of the transmitted symbols on the transmitting antennas in the first two symbol periods based on the received signal, including: The decoding end determines the power of the transmitted symbols on the transmitting antenna for the first two symbol periods according to the following formula. : ； ； ； ； ； ； ； Among them, the for The autocorrelation, the For the received signal vector in the 2t-1th symbol period, the For the noise vector, the To implement the signal received by the decoding end from the two transmitting antennas of the encoding end after passing through the channel and noise, the... and These are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively. For the channel matrix, the and The signal received by the decoding end in the 2t-1 symbol period, the and The received noise at the decoding end in the 2t-1 symbol period is... and These are symbol vectors of dimension L, originating from the two transmitting antennas after encoding at the encoding end and extending to the receiving antenna at the decoding end. This is signal noise.

6. The method according to claim 3, characterized in that, The decoding end decodes the original encoded input symbol for the current symbol period based on the encoded coefficient vector, the DSTBC encoding method, the NSTBC codebook, and the sum of the power of the transmitted symbols on the transmitting antennas of the previous two symbol periods. It also includes: The decoding end is based on the formula: ， Decode the original encoded input symbol in the 2t+1 symbol period; Among them, the and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the It is the square root of the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

7. The method according to claim 4 or 6, characterized in that, The method further includes: The decoding end determines the original bits or original symbols based on the... The preset mapping table determines the original bit or original symbol; The preset mapping table contains the original bits or original symbols and the coding coefficient vector. The mapping relationship between them after the initial reference symbol is determined.

8. The method according to claim 4 or 6, characterized in that, The method further includes: The decoding end inputs symbols based on the decoded original encoded data. Determine the original symbol ; The decoding end is based on the Determine the original bits.

9. The method according to claim 4, characterized in that, The method further includes: The decoding end determines the original encoded input symbol for the first symbol period as... , and the original encoded input symbol for the second symbol period is ; The original encoded input symbols This is the initial reference symbol; The decoding end is based on the formula: ， Decode the original encoded input symbol for the third symbol period; in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied: 。 10. The method according to claim 6, characterized in that, The method further includes: The decoding end determines the original encoded input symbol for the first symbol period as... , and the original encoded input symbol for the second symbol period is ; The original encoded input symbols This is the initial reference symbol; The decoding end is based on the formula: ， Decode the original encoded input symbol for the third symbol period; in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied: 。 11. The method according to claim 2, characterized in that, The decoding end determines the signal vector based on the received signal and the NSTBC codebook, including: The decoding end is based on the formula: ； ； Determine the signal vector ; Among them, the The signal received by the decoding end in the 2t-1 symbol period, the The signal received by the decoding end in the 2t symbol period, the The signal received by the decoding end in the 2t+1 symbol period, the This refers to the signal received by the decoding end in the 2t+2 symbol period.

12. The method according to claim 11, characterized in that, The signal vector satisfy: ； ； in, It is a linear combination vector of the useful signals. This is the noise interference vector.

13. The method according to claim 12, characterized in that, The satisfy: ； ； The satisfy: ； ； ； ； ； ； in, and These are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively. and stated The original encoded input symbol decoded by the decoding end in the 2t-1 symbol period, the The original encoded input symbol decoded by the decoding end in the 2t-th symbol period, the and stated The original encoded input symbol decoded by the decoding end in the (2t+1)th symbol period, the and stated The original encoded input symbol decoded by the decoding end in the 2t+2 symbol period; The The channel matrix; The The above The above This is the noise vector; The The received noise at the decoding end in the 2t-1 symbol period is... The received noise at the decoding end in the 2t-th symbol period is... The received noise at the decoding end in the 2t+1 symbol period is... This refers to the received noise at the decoding end during the 2t+2 symbol period.

14. A decoding device, characterized in that, include: The first determining module is used by the decoding end to determine the coding coefficient vector based on the received signal and the NSTBC codebook; The second determining module is used by the decoding end to determine the sum of the power of the transmitted symbols on the transmitting antenna in the first two symbol periods based on the received signal; The differential decoding module is used by the decoding end to decode the original encoded input symbol of the current symbol period based on the encoding coefficient vector, the differential space-time block code DSTBC encoding method, the NSTBC codebook, and the power of the transmitted symbols on the transmitting antenna of the previous two symbol periods. The previous two symbol periods are the two adjacent symbol periods before the current symbol period. The codebook structure of the NSTBC codebook satisfies: ； Among them, the and stated The original encoded input symbol for the 2t+1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the (2t+2)th symbol period decoded by the decoding end; wherein the symbol For symbols conjugate, symbol For symbols The negative conjugate of the symbol; the 2t+1th symbol period is the current symbol period, and the 2t+2th symbol period is the next symbol period of the current symbol period.

15. The apparatus according to claim 14, characterized in that, The first determining module is specifically used for: The decoding end determines the signal vector based on the received signal and the NSTBC codebook; The decoding end determines the coding coefficient vector of the decoding end in the current symbol period based on the signal vector.

16. The apparatus according to claim 15, characterized in that, The first determining module is specifically used for: The decoding end is based on the formula: ； Determine the coding coefficient vector of the decoding end in the (2t+1)th symbol period. ; Among them, the For the set of encoding coefficient vectors, the For the signal vector, the This is the coding coefficient vector determined by the decoder in the 2t+1 symbol period.

17. The apparatus according to claim 16, characterized in that, The differential decoding module is specifically used for: The decoding end is based on the formula: ， Decode the original encoded input symbol in the 2t+1 symbol period; Among them, the and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the This is the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

18. The apparatus according to claim 14, characterized in that, The second determining module is specifically used for: The decoding end determines the power of the transmitted symbols on the transmitting antenna for the first two symbol periods according to the following formula. : ； ； ； ； ； ； ； Among them, the for The autocorrelation, the For the received signal vector in the 2t-1th symbol period, the For the noise vector, the To implement the signal received by the decoding end from the two transmitting antennas of the encoding end after passing through the channel and noise, the... and These are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively. For the channel matrix, the and The signal received by the decoding end in the 2t-1 symbol period, the and The received noise at the decoding end in the 2t-1 symbol period is... and These are symbol vectors of dimension L, originating from the two transmitting antennas after encoding at the encoding end and extending to the receiving antenna at the decoding end. This is signal noise.

19. The apparatus according to claim 16, characterized in that, The differential decoding module can also be used for: The decoding end is based on the formula: ， Decode the original encoded input symbol in the 2t+1 symbol period; Among them, the and stated The original encoded input symbol for the 2t-1th symbol period decoded by the decoding end, the and stated The original encoded input symbol for the 2t-th symbol period decoded by the decoding end, the It is the square root of the sum of the power of the transmitted symbols on the two transmit antennas at the encoding end during the 2t-1 symbol period.

20. The apparatus according to claim 17, characterized in that, The device further includes: The third determining module is used by the decoding end to determine the original bits or original symbols based on the original bits or original symbols. The preset mapping table determines the original bit or original symbol; The preset mapping table contains the original bits or original symbols and the coding coefficient vector. The mapping relationship between them after the initial reference symbol is determined.

21. The apparatus according to claim 17 or 19, characterized in that, The device further includes: The fourth determining module is used by the decoding end to input symbols based on the decoded original encoded data. Determine the original symbol ; The decoding end is based on the Determine the original bits.

22. The apparatus according to claim 17, characterized in that, The device further includes: The fifth determining module is used by the decoding end to determine the original encoded input symbol of the first symbol period as... , and the original encoded input symbol for the second symbol period is ; The original encoded input symbols This is the initial reference symbol; The differential decoding module is also used by the decoding end to perform the following calculation: ， Decode the original encoded input symbol for the third symbol period; in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied: 。 23. The apparatus according to claim 19, characterized in that, The device further includes: The fifth determining module is used by the decoding end to determine the original encoded input symbol of the first symbol period as... , and the original encoded input symbol for the second symbol period is ; The original encoded input symbols This is the initial reference symbol; The differential decoding module is also used by the decoding end to perform the following calculation: ， Decode the original encoded input symbol for the third symbol period; in, The encoding coefficient vector obtained by the decoding end in the third symbol period, the With the The following NSTBC codebook is satisfied: 。 24. The apparatus according to claim 15, characterized in that, The first determining module is specifically used for: The decoding end is based on the formula: ； ； Determine the signal vector ; Among them, the The signal received by the decoding end in the 2t-1 symbol period, the The signal received by the decoding end in the 2t symbol period, the The signal received by the decoding end in the 2t+1 symbol period, the This refers to the signal received by the decoding end in the 2t+2 symbol period.

25. The apparatus according to claim 24, characterized in that, The signal vector satisfy: ； ； in, It is a linear combination vector of the useful signals. This is the noise interference vector.

26. The apparatus according to claim 25, characterized in that, The satisfy: ； ； The satisfy: ； ； ； ； ； ； in, and These are the channel gains from the two transmitting antennas after encoding at the encoding end to the receiving antenna at the decoding end, respectively. and stated The original encoded input symbol decoded by the decoding end in the 2t-1 symbol period, the The original encoded input symbol decoded by the decoding end in the 2t-th symbol period, the and stated The original encoded input symbol decoded by the decoding end in the (2t+1)th symbol period, the and stated The original encoded input symbol decoded by the decoding end in the 2t+2 symbol period; The The channel matrix; The The above The above This is the noise vector; The The received noise at the decoding end in the 2t-1 symbol period is... The received noise at the decoding end in the 2t-th symbol period is... The received noise at the decoding end in the 2t+1 symbol period is... This refers to the received noise at the decoding end during the 2t+2 symbol period.

27. A decoding terminal, characterized in that, It includes a processor and a memory, the memory storing a program or instructions that can run on the processor, the program or instructions being executed by the processor to implement the steps of the decoding method as described in any one of claims 1 to 13.

28. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions that, when executed by a processor, implement the steps of the decoding method as described in any one of claims 1 to 13.

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