Short code RM coding method and device based on multipath channel, medium and program product

Abstract

The invention relates to the technical field of wireless communication, and provides a short code RM coding method and device based on a multipath channel, a medium and a program product, in the method, RM coding redundancy bits are increased in groups to resist deviation of a related maximum value and an ideal position caused by symbol offset brought by other secondary path delays; meanwhile, as the spread spectrum can expand the signal on a relatively wider frequency band and can reduce the propagation problem caused by multipath and attenuation, the spread spectrum processing is carried out on the data after the RM redundant coding is carried out, so that the sent information has very strong anti-multipath capability, and the performance of RM coding and decoding in a multipath environment is greatly improved.

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 code (RM code) is a type of linear block code that can correct multiple errors. This type of code is simple in construction and has rich structural characteristics. It can be decoded by soft decision or hardware decision algorithms. Therefore, it is widely used in practical engineering. For short code encoding of control information, RM code has a great advantage. Many articles have studied decoding methods. At present, most of them use Walsh-Hadamard transform (DWHT) decoding algorithm based on soft decision, which has higher performance in AWGN channel, but in multipath channel, the performance of conventional RM coding will decline sharply.

[0003] Since the essence of RM decoding is to find the correlation to determine the maximum value, the influence of fading and the superposition of multipaths 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 prone to occur at positions adjacent to the maximum value. Summary of the invention

[0004] In view of the above problems, the present invention provides a method, device, medium and program product based on short code RM coding in a multipath channel. In the method, RM coding redundant bits are added by grouping to resist the deviation of the correlation maximum value from the ideal position caused by the symbol offset caused by the delay of the remaining secondary paths; at the same time, since spread spectrum can expand the signal over a relatively wider frequency band, it can reduce the propagation problems caused by multipath and attenuation. Therefore, after RM redundant coding, the data is spread spectrum processed again, so that the transmitted information has a strong anti-multipath capability, which greatly improves the performance of RM encoding and decoding in a multipath environment.

[0005] The present invention provides a method for short code RM encoding based on 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: According to the length L of the transmitted information, a Hadamard matrix of the corresponding order is constructed, and some columns in the Hadamard matrix are taken to form a generator matrix G;

[0008] Step 3: Perform RM encoding based on the preprocessed 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 a 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 value 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: Remove redundant bits by grouping according to the length of L 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, add 1 bit 0 at 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 1-bit 0 is inserted at the end of the first N / 2 bits of the transmitted information and another 1-bit 0 is added at the end of the last N / 2 bits, and 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 through 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 spread sequence d=[d1d2] to obtain the spread 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 also 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, increases redundant bits by grouping, and improves the performance of RM coding in a multipath environment without changing the original coding structure;

[0031] 2. The present invention adds a spread spectrum process after RM coding to extend 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 a multipath environment;

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

[0033] Figure 1 The present invention 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 in a multipath Rice channel (the first path has a stronger power).

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

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

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

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 here 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 claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are 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 based on a multipath channel, comprising the following steps:

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

[0043] Step 2: According to the length L of the transmitted information, a Hadamard matrix of the corresponding order is constructed, and some columns in the Hadamard matrix are taken to form a 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 a 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 value 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: Remove redundant bits by grouping according to the length of L to obtain decoded information.

[0052] Specific example:

[0053] Take the example of sending information with a length of 6 bits, and perform RM encoding. Figure 1 As shown, the present embodiment proposes a method for short code RM encoding based on a multipath channel, comprising the following steps:

[0054] Step 1: Preprocess the information to be sent, group it and add redundant bits according to the length of the information to be sent. If the length of the information to be sent is less than or equal to 5 bits, add 1 bit of 0 at the end of the information to be sent, and the length of the information to be sent is N+1; if the length of the information to be sent is greater than 5 bits, insert 1 bit of 0 at the end of the first N / 2 bits of the information to be sent, and add 1 bit of 0 at the end of the last N / 2 bits of the information to be sent, and the length of the information to be sent is N+2. In the example, the length of the information to be sent is 6 bits, the first 3 bits are grouped together and 0 is added at the end, and the last 3 bits are grouped together and 0 is added at the end, so that the information to be sent 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 sending information bits.

[0057] Step 2: According to the length L of the transmitted information, a 2^L-order Hadamard matrix is ​​constructed, and 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 of only +1 and -1 elements and its rows and columns are mutually orthogonal. A high-order Hadamard matrix of order 2 can be derived by recursion from the 2nd-order Hadamard matrix:

[0060] and

[0061] Where H N 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, in this example, the length of the data V_Rx obtained after despreading 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: Remove redundant bits by grouping according to the length of L. 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 the 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 in 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 embodiment of the present application. Figure 4 The example in this article is that the processor and memory are connected through a bus. Figure 4 The connections between other components are shown in bold lines, which are only for illustration and are not intended to be limiting. The bus can be divided into address bus, data bus, control bus, etc. Figure 4 In the diagram, only one thick line is used, but this does not mean that there is only one bus or only one type of bus. Alternatively, a processor can also be called a controller, and there is no limitation on the name.

[0085] In the embodiment of the present application, the memory stores instructions that can be executed by at least one processor, and at least one processor can execute the method of short code RM encoding based on 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, 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 mainly processes an operating system, a user interface, and application programs, and the modem processor mainly processes wireless communications. It is understandable that the modem processor may not be integrated into the processor. In some embodiments, the processor and the memory may be implemented on the same chip, and in some embodiments, they may also be implemented separately on separate chips.

[0088] The processor may 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 may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present application. A general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of a method for short code RM encoding based on a multipath channel disclosed in the embodiments of the present application may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0089] As a non-volatile computer-readable storage medium, the memory can be used to store non-volatile software programs, non-volatile computer executable programs and modules. The memory can include at least one type of storage medium, for example, it can include flash memory, hard disk, multimedia card, card-type memory, random access memory (Random Access s Memory, RAM), static random access memory (Static Random Access Memory, SRAM), programmable read-only memory (Programmable Read Only Memory, PROM), read-only memory (Read Only Memory, ROM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), magnetic storage, disk, optical disk, etc. The memory is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures 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 any other device that can realize 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 based on a multipath channel introduced in the above embodiment can be fixed into the chip, so that the chip can perform the steps of the method for short code RM encoding based on a multipath channel in the above embodiment when running. How to design and program the processor is a technology known to those skilled in the art and will not be described in detail 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 a 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 a 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 above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of a unit described above can be further divided into multiple units to be embodied. In addition, although the operation of the method of the present application is 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 result. Additionally or alternatively, some steps can be omitted, multiple steps can be combined into one step for execution, and / or one step can be decomposed into multiple steps for execution.

[0094] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may 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 may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include 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 process in the flowchart. 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] Program code for performing 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++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a stand-alone software package, partially on the user 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., via the Internet using an Internet service provider).

[0098] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate 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 A 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 operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for short code RM coding 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: According to the length L of the transmitted information, a Hadamard matrix of the corresponding order is constructed, and some columns in the Hadamard matrix are taken to form a generator matrix G; Step 3: Perform RM encoding based on the preprocessed 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 a data sequence; Step 6: Despread the data sequence; Step 7: Perform fast Hadamard transform on the despread data; Step 8: Calculate the modulus value 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: Remove redundant bits by grouping according to the length of L 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, add 1 bit 0 at 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 1-bit 0 is inserted at the end of the first N / 2 bits of the transmitted information and another 1-bit 0 is added at the end of the last N / 2 bits, and 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 generator matrix G is formed by taking 2^(0:L) columns in the Hadamard matrix.

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 spread spectrum sequence d = [d1 d2] to obtain the spread spectrum 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 as described in 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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