Method, device, medium and program product based on short code RM encoding in multipath channel

Abstract

The present invention relates to the field of wireless communication technology and provides a method, device, medium, and program product based on short-code RM encoding in a multipath channel. In the method, RM coding redundant bits are added by grouping to counteract the deviation of the correlation maximum value from the ideal position caused by symbol offset due to delays in other secondary paths. At the same time, because spread spectrum can spread signals over a relatively wider frequency band, it can reduce propagation problems caused by multipath and attenuation. Therefore, after performing RM redundant encoding, spread spectrum processing is performed on the data, so that the transmitted information has a strong anti-multipath capability, greatly improving the performance of RM encoding and decoding in a multipath environment.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a method, device, medium and program product based on short code RM encoding in a multipath channel. Background Art

[0002] Reed-Muller codes (RM codes) are a class of linear block codes capable of correcting multiple errors. These codes are simple to construct, feature rich structural properties, and can be decoded using either soft-decision or hardware-decision algorithms. Consequently, they are widely used in practical engineering applications. RM codes offer significant advantages for encoding short codes such as control information, and numerous research papers have investigated their decoding methods. Currently, most utilize soft-decision Walsh-Hadamard Transform (DWHT) decoding algorithms, which offer high performance in AWGN channels. However, conventional RM encoding and decoding performance degrades dramatically in multipath channels.

[0003] Since the essence of RM decoding is to find the correlation value, the influence of fading and the superposition of multipath will lead to sampling deviation. There is a situation where the power of the secondary path is greater than the power of the main path. When finding the correlation, the maximum value will shift near the ideal position, such as Figure 2a 、 Figure 2b 、 Figure 2c As shown, decoding errors are likely to occur at positions adjacent to the maximum value. Summary of the Invention

[0004] To address the above-mentioned issues, the present invention provides a method, device, medium, and program product based on short-code RM encoding in a multipath channel. In this method, RM coding redundancy bits are added through grouping to counteract the deviation of the correlation maximum value from the ideal position caused by symbol offset due to delays in other secondary paths. At the same time, because spread spectrum can spread the signal over a relatively wider frequency band, it can reduce propagation problems caused by multipath and attenuation. Therefore, after performing RM redundant encoding, spread spectrum processing is performed on the data, which makes the transmitted information highly resistant to multipath, greatly improving the performance of RM encoding and decoding in a multipath environment.

[0005] The present invention provides a method for short code RM encoding in a multipath channel, comprising the following steps:

[0006] Step 1: Preprocess the transmitted information, group it according to its length and add redundant bits to obtain the preprocessed transmitted information C and length L;

[0007] Step 2: Based on the length of the transmitted information L, a Hadamard matrix of the corresponding order is constructed, and some columns of the Hadamard matrix are taken to form the generator matrix G;

[0008] Step 3: Perform RM encoding based on the pre-processed transmission information C and the generator matrix G;

[0009] Step 4: Spread the sequence obtained after RM encoding;

[0010] Step 5: Add noise and multipath channel to the spread sequence to obtain the data sequence;

[0011] Step 6: Despread the data sequence;

[0012] Step 7: Perform fast Hadamard transform on the despread data;

[0013] Step 8: Calculate the modulus of the fast Hadamard transform result, search for the maximum value, and record the maximum value position;

[0014] Step 9: The maximum value position is represented in decimal and converted into a binary number with a length of L;

[0015] Step 10: Group by length L and remove redundant bits to obtain decoded information.

[0016] In some embodiments, the pre-processing in step 1 includes:

[0017] If the length of the transmitted information N is less than or equal to the preset X bits, a 0 bit is added to the end of the transmitted information, and the length of the transmitted information L is N+1;

[0018] If the length N of the transmitted information is greater than the preset X bits, a 0-bit is inserted at the end of the first N / 2 bits of the transmitted information and another 0-bit is added at the end of the last N / 2 bits of the transmitted information. The length L of the transmitted information is N+2.

[0019] In some embodiments, in step 2, a 2^L-order Hadamard matrix is ​​constructed according to the length L of the transmitted information, and 2^(0:L) columns in the Hadamard matrix are taken to form a generator matrix G.

[0020] In some embodiments, a 2^L-order Hadamard matrix is ​​obtained by recursion using a 2-order Hadamard matrix.

[0021] In some embodiments, in step 3, RM encoding is performed to obtain a sequence V=C·G.

[0022] In some embodiments, in step 4, the sequence V obtained after RM encoding is spread according to the spreading sequence d=[d1d2] to obtain the spreading sequence

[0023] In some embodiments, in step 6, the data sequence V_s_Rx is despread to obtain V_Rx=V_s_Rx·d'; wherein,

[0024] The present invention further provides an electronic device, comprising:

[0025] at least one processor; and a memory communicatively coupled to the at least one processor;

[0026] The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the above method by executing the instructions stored in the memory.

[0027] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store instructions, and when the instructions are executed, the above method is implemented.

[0028] The present invention also provides a computer program product, which, when called by a computer, enables the computer to execute the above method.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] 1. The present invention pre-processes the transmitted information and increases redundant bits by grouping, thereby improving the performance of RM codec in a multipath environment without changing the original codec structure.

[0031] 2. The present invention adds a spread spectrum process after RM coding to spread the transmitted signal to a relatively wider frequency band, further reducing the propagation problems caused by multipath and attenuation, and further improving the performance of RM coding in multipath environments;

[0032] 3. Although the present invention increases packet redundancy bits at the transmitting end, a fast Hadamard transform is performed on the data at the receiving end. This is a fast butterfly transform that can greatly save computing resources. Therefore, the increase in redundancy bits has very little impact on resource consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The figure is a flowchart of a method for short code RM encoding based on a multipath channel in an embodiment of the present invention.

[0034] Figure 2a is the correlation peak under Gaussian channel.

[0035] Figure 2b is the correlation peak under the multipath Rice channel (the first path power is stronger).

[0036] Figure 2c is the correlation peak under the multipath Rice channel (the second path power is stronger).

[0037] Figure 3 Schematic diagram of the butterfly operation process in an embodiment of the present invention.

[0038] Figure 4The figure is a schematic structural diagram of an electronic device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention.

[0041] like Figure 1 As shown, the present embodiment proposes a method for short code RM encoding in a multipath channel, including the following steps:

[0042] Step 1: Preprocess the transmitted information and group it according to its length and add redundant bits. If the transmitted information length N is less than or equal to X bits, add a 0 bit to the end of the transmitted information, and the transmitted information length L is N+1. If the transmitted information length N is greater than X bits, insert a 0 bit at the end of the first N / 2 bits of the transmitted information and another 0 bit at the end of the last N / 2 bits of the transmitted information, and the transmitted information length L is N+2. X can be set as required.

[0043] Step 2: Based on the length of the transmitted information L, a Hadamard matrix of the corresponding order is constructed, and some columns of the Hadamard matrix are taken to form the generator matrix G;

[0044] Step 3: Perform RM (Reed-Muller) encoding based on the preprocessed transmission information C and the generator matrix G;

[0045] Step 4: Spread the sequence obtained after RM encoding;

[0046] Step 5: Add noise and multipath channel to the spread sequence to obtain the data sequence;

[0047] Step 6: Despread the data sequence;

[0048] Step 7: Perform Fast Hadamard Transform (FHT) on the despread data.

[0049] Step 8: Calculate the modulus of the fast Hadamard transform result, search for the maximum value, and record the maximum value position;

[0050] Step 9: The maximum value position is represented in decimal and converted into a binary number with a length of L;

[0051] Step 10: Group by length L and remove redundant bits to obtain decoded information.

[0052] Specific examples:

[0053] Take the length of the information sent as 6 bits as an example, and perform RM encoding. Figure 1 As shown, the present embodiment proposes a method for short code RM encoding in a multipath channel, including the following steps:

[0054] Step 1: Preprocess the transmitted information, grouping it according to its length and adding redundant bits. If the transmitted information length N is less than or equal to 5 bits, add a 0 bit to the end of the transmitted information, and the transmitted information length L is N+1. If the transmitted information length N is greater than 5 bits, insert a 0 bit at the end of the first N / 2 bits of the transmitted information and another 0 bit at the end of the last N / 2 bits of the transmitted information, and the transmitted information length L is N+2. In this example, the transmitted information length is 6 bits. Group the first 3 bits and add 0 to the end, and group the last 3 bits and add 0 to the end, so that the transmitted information becomes C, and the length L is 8.

[0055] C=[c1 c2 c3 0 c4 c5 c6 0]

[0056] Among them, c i ,i=1,2,…,6 represents the information bits sent.

[0057] Step 2: Based on the length of the transmitted information L, a 2^L-order Hadamard matrix is ​​constructed, and the 2^(0:L) columns in the Hadamard matrix are taken to form the generator matrix G;

[0058] Step 201: Generate a Hadamard matrix with a length of 2^8=256.

[0059] A Hadamard matrix is ​​a square matrix consisting only of +1 and -1 elements, with orthogonal rows and columns. A high-order Hadamard matrix of order N, which is a power of 2, can be derived recursively from the 2nd-order Hadamard matrix:

[0060] and

[0061] Where H N It is an N-order (N=2 m )Hadamard matrix table; represents the direct product (KronecderProduct). The recursive process of the Hadamard matrix is ​​shown below.

[0062]

[0063]

[0064] According to the above recursive process, the 256-order Hadamard matrix H is generated. 256 .

[0065] Step 202: Take out the 256-order Hadamard matrix H 256 The 2^(0:L)th column of constitutes the generator matrix G required for RM coding.

[0066] Step 3: Perform RM (Reed-Muller) encoding based on the preprocessed transmission information C and the generator matrix G to obtain a sequence V with a length of 256;

[0067] V=C·G

[0068] Here, represents matrix multiplication.

[0069] Step 4: Spread the sequence obtained after RM encoding according to the spreading sequence d = [d1d2] to obtain the spreading sequence V_s;

[0070]

[0071] Step 5: Add noise and multipath channel to the spread sequence to obtain the data sequence V_s_Rx;

[0072] Step 6: Despread the data sequence V_s_Rx to obtain:

[0073] V_Rx=V_s_Rx·d'

[0074] in,

[0075] Step 7: Perform fast Hadamard transform on the despread data V_Rx to obtain the sequence V_FHT;

[0076] Assuming that the length of the received signal Rx is 8, the fast Hadamard transform requires 3 levels of butterfly operations to obtain Rx_FHT. The butterfly operation process is as follows: Figure 3 As shown, the sequence after the 3-level butterfly operation is:

[0077]

[0078] In summary, the length of the despread data V_Rx in this example is 256, and an 8-level FHT butterfly operation is required:

[0079] Step 8: Perform modulus calculation on the despread data V_FHT, search for the maximum value, and record the maximum value position max_ind.

[0080] Step 9: According to the maximum value position max_ind, convert it into a binary with a length of L, such as:

[0081] C'=[c'1 c'2 c'3 c'4 c'5 c'6 c'7 c'8]

[0082] Step 10: Group by length L and remove redundant bits. If L is less than or equal to 6, the decoded information is L(1:L-1); if L is greater than 6, the decoded information is L([1:L / 2-1L / 2+1:L-1]). Since L=8 in this embodiment, the decoded information obtained after removing redundant bits is: [c'1 c'2 c'3 c'5 c'6 c'7].

[0083] Based on the same technical concept, the embodiment of the present application also provides an electronic device, which can implement the method flow based on short code RM encoding under multipath channel provided by the above embodiment of the present application. In one embodiment, the electronic device can be a server, or a terminal device or other electronic device. Figure 4 As shown, the electronic device may include:

[0084] At least one processor, and a memory connected to the at least one processor. The specific connection medium between the processor and the memory is not limited in the embodiments of the present application. Figure 4 The example in this article is that the processor and memory are connected via a bus. Figure 4 The connections between the other components are shown in bold lines, which are only for illustration and not intended to be limiting. The bus can be divided into address bus, data bus, control bus, etc. Figure 4 The processor is represented by a single thick line, but this does not mean that there is only one bus or only one type of bus. Alternatively, the processor can also be called a controller, without any limitation on the name.

[0085] In an embodiment of the present application, the memory stores instructions that can be executed by at least one processor. The at least one processor can execute the short code RM encoding method based on a multipath channel discussed above by executing the instructions stored in the memory. The processor can implement Figure 4 The functions of each module in the device shown.

[0086] Among them, the processor is the control center of the device, which can use various interfaces and lines to connect the various parts of the entire control device, and monitor the device as a whole by running or executing instructions stored in the memory and calling data stored in the memory, the various functions of the device and processing data.

[0087] In an optional design, the processor may include one or more processing units, and the processor may integrate an application processor and a modem processor, wherein the application processor primarily processes the operating system, user interface, and application programs, and the modem processor primarily processes wireless communications. It is understood that the modem processor may not be integrated into the processor. In some embodiments, the processor and memory may be implemented on the same chip, or in some embodiments, they may be implemented on separate chips.

[0088] The processor can be a general-purpose processor, such as a CPU, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method for short-code RM encoding in a multipath channel disclosed in the embodiments of this application can be directly implemented and executed by a hardware processor, or by a combination of hardware and software modules in the processor.

[0089] As a non-volatile computer-readable storage medium, memory can be used for storing non-volatile software programs, non-volatile computer executable programs and modules.Memory can include at least one type of storage medium, for example, can include flash memory, hard disk, multimedia card, card-type memory, random access memory (RAM), static random access memory (SRAM), programmable read-only memory (PROM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), magnetic storage, disk, optical disk, etc. Memory is any other medium that can be used to carry or store the desired program code with instruction or data structure form and can be accessed by a computer, but is not limited thereto. The memory in the embodiment of the present application can also be a circuit or other arbitrarily capable of realizing a storage function, for storing program instructions and / or data.

[0090] By designing and programming the processor, the code corresponding to the method for short-code RM encoding in a multipath channel described in the aforementioned embodiment can be embedded in the chip, allowing the chip to execute the steps of the method for short-code RM encoding in a multipath channel described in the aforementioned embodiment during operation. Designing and programming the processor is well known to those skilled in the art and will not be detailed here.

[0091] Based on the same inventive concept, an embodiment of the present application further provides a storage medium storing computer instructions. When the computer instructions are executed on a computer, the computer executes the method of short code RM encoding based on a multipath channel discussed above.

[0092] In some optional embodiments, the present application also provides various aspects of a method for short code RM encoding under a multipath channel, which can also be implemented in the form of a program product, which includes program code. When the program product is run on an apparatus, the program code is used to enable the control device to execute the steps of a method for short code RM encoding under a multipath channel according to various exemplary embodiments of the present application described above in this specification.

[0093] It should be noted that although several units or subunits of the device are mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to the embodiment of the present application, the features and functions of two or more units described above can be concretized in one unit. Conversely, the features and functions of a unit described above can be further divided into multiple units to be concretized. In addition, although the operations of the present application method are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. Additionally or alternatively, certain steps can be omitted, multiple steps can be combined into one step, and / or one step can be decomposed into multiple steps.

[0094] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0095] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a server, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0096] The program code used to perform the operations of the present application may be written using any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's device, as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0097] Where a remote computing device is involved, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0098] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0100] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for short code RM encoding based on multipath channel, characterized in that: The steps include: Step 1: Preprocess the transmitted information, group it according to its length and add redundant bits to obtain the preprocessed transmitted information C and length L; Step 2: Based on the length of the transmitted information L, a Hadamard matrix of the corresponding order is constructed, and some columns of the Hadamard matrix are taken to form the generator matrix G; Step 3: Perform RM encoding based on the pre-processed transmission information C and the generator matrix G; Step 4: Spread the sequence obtained after RM encoding; Step 5: Add noise and multipath channel to the spread sequence to obtain the data sequence; Step 6: Despread the data sequence; Step 7: Perform fast Hadamard transform on the despread data; Step 8: Calculate the modulus of the fast Hadamard transform result, search for the maximum value, and record the maximum value position; Step 9: The maximum value position is represented in decimal and converted into a binary number with a length of L; Step 10: Group by length L and remove redundant bits to obtain decoded information.

2. The method for short code RM encoding based on multipath channel according to claim 1, characterized in that: The preprocessing in step 1 includes: If the length of the transmitted information N is less than or equal to the preset X bits, a 0 bit is added to the end of the transmitted information, and the length of the transmitted information L is N+1; If the length N of the transmitted information is greater than the preset X bits, a 0-bit is inserted at the end of the first N / 2 bits of the transmitted information and another 0-bit is added at the end of the last N / 2 bits of the transmitted information. The length L of the transmitted information is N+2.

3. The method for short code RM encoding based on multipath channel according to claim 1, characterized in that: In step 2, a 2^L-order Hadamard matrix is ​​constructed according to the length L of the transmitted information, and the 2^(0:L) columns in the Hadamard matrix are taken to form the generator matrix G.

4. The method for short code RM encoding based on multipath channel according to claim 3, characterized in that: The 2^L-order Hadamard matrix is ​​obtained by recursion through the 2-order Hadamard matrix.

5. The method for short code RM encoding based on multipath channel according to claim 1, characterized in that: In step 3, RM encoding is performed to obtain a sequence V=C·G.

6. The method for short code RM encoding based on multipath channel according to claim 5, characterized in that: In step 4, the sequence V obtained after RM encoding is spread according to the spreading sequence d = [d1 d2] to obtain the spreading sequence 7. The method for short code RM encoding based on multipath channel according to claim 6, characterized in that: In step 6, the data sequence V_s_Rx is despread to obtain V_Rx=V_s_Rx·d'; wherein, 8. An electronic device, characterized in that: include: at least one processor; and a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the at least one processor executes the method according to any one of claims 1 to 7 by executing the instructions stored in the memory.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium is used to store instructions, and when the instructions are executed, the method according to any one of claims 1 to 7 is implemented.

10. A computer program product, characterized in that When the computer program product is called by a computer, the computer is caused to execute the method according to any one of claims 1 to 7.

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