Decoder llr weight acquisition method, decoding method, system, device and medium

Abstract

The application provides a decoder LLR weight acquisition method, comprising the following steps: acquiring a noise variance estimation value of a received signal by using a difference value of channel estimation values of two adjacent symbols of the received signal; acquiring an equivalent power estimation value of the received signal by using an amplitude value of the channel estimation value; and obtaining an LLR weight based on a ratio of the equivalent power estimation value of the received signal to the noise variance estimation value. The decoder LLR weight acquisition method utilizes the similarity of channels between adjacent symbols, can accurately obtain the noise estimation value of the received signal, and further ingeniously utilizes the channel amplitude response value to reflect the relative power size of the received signal sequence. Finally, the fine-grained real-time LLR weight value can be obtained through the ratio of the two, so that the technical defects of the existing simplified model scheme, such as the large performance loss under complex channel conditions, and the fixed weight value scheme, such as the narrow adaptation range and the performance that cannot be fully released, are overcome, and the best decoding performance of the decoder is ensured.

Description

Technical Field

[0001] The present application relates to the field of channel coding technology, and more specifically, to a decoder LLR weight acquisition method, a decoding method, a system, a device and a medium. Background Art

[0002] To improve system robustness, channel coding techniques are often introduced in wireless communication systems. Decoding schemes can be categorized as soft decoding or hard decoding. Soft decoding is more commonly used due to its superior performance compared to hard decoding. For soft decoding, the initial input to the decoder is the log-likelihood ratio (LLR) generated by the demodulation module. The sign of the LLR represents the hard decision result for that bit of data, while the absolute value represents the probability (also known as the confidence level) that the hard decision for that bit is correct.

[0003] In actual engineering, due to limited chip storage and computing resources, the absolute LLR values ​​generated by the demodulator are quantized. This quantization process is used to determine the confidence level of each symbol demodulation result. During quantization, the original LLR sequence is combined with the weight value and scaled to achieve an appropriate quantization interval. If the overall quantization of the original LLR sequence is too large or too small, there will be no distinction between "reliable values," "less reliable values," and "erroneous values" in the demodulation result, resulting in information loss and, in turn, a decline in decoder performance. Therefore, LLR weight values ​​are crucial to ensuring decoder performance.

[0004] There are currently two commonly used LLR weight value calculation schemes: 1. Theoretical calculation scheme of simplified model; 2. Fixed weight value scheme.

[0005] The simplified theoretical calculation scheme assumes the wireless transmission channel is a stable Gaussian channel, the signal modulation method is BPSK, and the received signal after transmission through the wireless channel is also assumed to follow a Gaussian distribution. Although this scheme can also derive a theoretical formula for LLR weights, it uses the simplest Gaussian channel model. The transmission characteristics of actual wireless channels are far more complex than a Gaussian model. Therefore, in practice, this weight calculation scheme results in significant decoder performance loss under complex channel conditions.

[0006] Because there's currently no theoretical formula for calculating LLR weights under complex channels and different modulation schemes, the industry often uses fixed weights. However, these weights must be obtained through system simulation under specific transmission conditions, and these fixed weights are only near-optimal under those conditions. This narrow adaptation range hinders the decoder's full decoding performance in actual communications. Summary of the Invention

[0007] In response to at least one defect or improvement need in the prior art, the present application provides a decoder LLR weight acquisition method, decoding method, system, device and medium, which are used to at least obtain LLR weight values ​​under the premise of complex channels and different modulation schemes to ensure the optimal decoding performance of the decoder.

[0008] To achieve the above objectives, in a first aspect, the present application provides a decoder LLR weight acquisition method, comprising:

[0009] Obtaining a noise variance estimation value of the received signal by using a difference between channel estimation values ​​of two adjacent symbols of the received signal;

[0010] Obtaining an equivalent power estimation value of the received signal using an amplitude value of a channel estimation value of a symbol of the received signal;

[0011] The LLR weight is obtained based on a ratio of an equivalent power estimate of the received signal to a noise variance estimate of the received signal.

[0012] Furthermore, the formula for obtaining the LLR weight includes:

[0013]

[0014] Wherein, w represents the LLR weight; p represents the equivalent power estimation value of the received signal; σ 2 represents the noise variance estimation value of the received signal; λ represents a constant.

[0015] Furthermore, the formula for obtaining the noise variance estimate of the received signal includes:

[0016]

[0017] The formula for obtaining the equivalent power estimate of the received signal includes:

[0018] p=abs(H n ) 2 ;

[0019] Among them, H n represents the channel estimation value of the symbol n of the received signal; mean represents the average value symbol; abs represents the absolute value symbol.

[0020] In a second aspect, the present application provides a decoding method, which can perform decoding based on any of the above-mentioned decoder LLR weight acquisition methods.

[0021] In a third aspect, the present application provides a decoder LLR weight acquisition system, comprising:

[0022] A noise variance estimation value acquisition module is used to obtain a noise variance estimation value of a received signal by using a difference between channel estimation values ​​of two adjacent symbols of the received signal;

[0023] An equivalent power estimation value acquisition module, configured to acquire an equivalent power estimation value of the received signal using an amplitude value of a channel estimation value of a symbol of the received signal;

[0024] The LLR weight acquisition module is configured to obtain the LLR weight based on a ratio of an equivalent power estimate of the received signal to a noise variance estimate of the received signal.

[0025] Furthermore, the formula for obtaining the LLR weight includes:

[0026]

[0027] Wherein, w represents the LLR weight; p represents the equivalent power estimation value of the received signal; σ 2 represents the noise variance estimation value of the received signal; λ represents a constant.

[0028] Furthermore, the formula for obtaining the noise variance estimate of the received signal includes:

[0029]

[0030] The formula for obtaining the equivalent power estimate of the received signal includes:

[0031] p=abs(H n ) 2 ;

[0032] Among them, H n represents the channel estimation value of the symbol n of the received signal; mean represents the average value symbol; abs represents the absolute value symbol.

[0033] In a fourth aspect, the present application provides a decoding system, which can execute the aforementioned decoding method for decoding.

[0034] In a fifth aspect, the present application provides an electronic device comprising at least one processing unit and at least one storage unit, wherein the storage unit stores a computer program, and when the computer program is executed by the processing unit, the processing unit is enabled to perform the steps of the decoder LLR weight acquisition method described in any one of the aforementioned items and / or to perform the steps of the aforementioned decoding method.

[0035] In a sixth aspect, the present application provides a storage medium storing a computer program executable by an access authentication device. When the computer program runs on the access authentication device, the access authentication device is enabled to execute the steps of the decoder LLR weight acquisition method described in any one of the aforementioned items and / or to execute the steps of the aforementioned decoding method.

[0036] In general, the above technical solutions conceived by this application can achieve the following beneficial effects compared with the existing technology:

[0037] (1) The decoder LLR weight acquisition method and system proposed in this application both utilize the similarity of the channels between adjacent symbols, and can accurately obtain the noise estimation value of the received signal; in addition, the channel amplitude response value is cleverly used to reflect the relative power size of the received signal sequence, and finally the fine-grained real-time LLR weight value can be obtained by the ratio of the first two. This overcomes the technical defects of the existing simplified model scheme that has a large performance loss under complex channel conditions and the fixed weight value scheme that has a narrow adaptation range and often cannot fully release the performance, thereby ensuring the optimal decoding performance of the decoder.

[0038] (2) The decoding method and system proposed in this application are both based on the aforementioned decoder LLR weight acquisition method for decoding, thereby overcoming the technical defects of the existing simplified model scheme that has a large performance loss under complex channel conditions and the fixed weight value scheme that has a narrow adaptation range and often cannot fully release the performance, thereby ensuring the optimal decoding performance of the decoder. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 A flowchart of a method for obtaining LLR weights for a decoder provided in an embodiment of the present application;

[0041] Figure 2 Frame error rate simulation results of three different schemes under a multipath channel model: the theoretical calculation scheme of the simplified model provided in the embodiment of the present application, the fixed weight value scheme, and the decoder LLR weight acquisition scheme proposed in the present application; ( Figure 2 The BLER in the code is the block error rate, which refers to the ratio of the number of error blocks in the digital circuit to the total number of blocks received.

[0042] Figure 3A block diagram of an electronic device suitable for implementing the decoder LLR weight acquisition method and / or decoding method described above, provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining this application and are not intended to limit this application. In addition, the technical features involved in the various embodiments of this application described below may be combined with each other as long as they do not conflict with each other.

[0044] The terms "first," "second," or "nth" in the specification, claims, or drawings of this application are used to distinguish different objects, not to describe a specific order. In addition, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to the process, method, product, or apparatus.

[0045] As described in the background section of this specification, the simplified model theoretical calculation scheme in the existing technology results in significant performance loss in decoder performance under complex channel conditions. Fixed weight value schemes also have a narrow adaptation range, which prevents the decoder from fully realizing its decoding performance during actual communications. To overcome these technical difficulties, this application proposes a decoder LLR weight acquisition method, decoding method, system, device, and medium.

[0046] refer to Figure 1 An embodiment of the present application proposes a method for obtaining decoder LLR weights, which may mainly include the following three steps.

[0047] Step 1: Obtain a noise variance estimation value of the received signal by taking the difference between the channel estimation values ​​of two adjacent symbols of the received signal.

[0048] More specifically, let the channel estimation value of the symbol n of the received signal be H n , n=1,2,…,m, where m is the number of symbols, then the calculation formula for the noise variance estimate contained in the received signal is referenced to formula (1).

[0049]

[0050] Among them, σ 2Represents the noise variance estimate of the received signal; mean represents the symbol of the average value; abs represents the symbol of the absolute value.

[0051] Step 2: Obtain an equivalent power estimation value of the received signal using the amplitude value of the channel estimation value of the symbol of the received signal.

[0052] More specifically, the calculation formula for the equivalent power estimation value of the received signal is referred to formula (2).

[0053] p=abs(H n ) 2 (2)

[0054] Where p represents the equivalent power estimate of the received signal; (H n ) 2 Indicates the amplitude value of the channel estimation value of symbol n of the received signal.

[0055] Step 3: Obtain the LLR weight based on the ratio of the equivalent power estimate of the received signal to the noise variance estimate of the received signal.

[0056] More specifically, the calculation formula of the LLR weight is referred to formula (3).

[0057]

[0058] Substituting equations (1) and (2) into equation (3) yields equation (4).

[0059]

[0060] Wherein, w represents the LLR weight; λ1 represents the first constant, and λ2 represents the second constant, both of which are constants.

[0061] refer to Figure 2 The curve labeled mthd1 is the frame error rate curve for the simplified theoretical calculation scheme; the curve labeled mthd2 is the frame error rate curve for the fixed weight value scheme; and the curve labeled mthd3 is the frame error rate curve for the scheme proposed in the embodiment of this application. The simulation results show that the frame error rate of the LLR weight calculation scheme proposed in the embodiment of this application is the lowest under the same conditions. Therefore, the LLR weight calculation scheme proposed in the embodiment of this application has a significant performance improvement.

[0062] The theory of the decoder LLR weight acquisition method proposed in this application is derived from the theoretical calculation scheme of the simplified model. Although formula (3) is derived from the simplified transmission channel model, it can be seen from formula (3) that the LLR weight is positively correlated with the signal-to-noise ratio of the received signal. This application uses the channel estimation result (channel estimation value) to calculate the LLR weight. The decoder LLR weight acquisition method proposed in this application utilizes the similarity of the channel between adjacent symbols and can accurately obtain the noise estimation value of the received signal. In addition, the channel amplitude response value is cleverly used to reflect the relative power size of the received signal sequence. Finally, the fine-grained real-time LLR weight value can be obtained by the ratio of the first two. This overcomes the technical defects of the existing simplified model scheme that has a large performance loss under complex channel conditions and the fixed weight value scheme that has a narrow adaptation range and often cannot fully release the performance, thereby ensuring the optimal decoding performance of the decoder.

[0063] An embodiment of the present application further provides a decoding method, which can perform decoding based on any of the above-mentioned decoder LLR weight acquisition methods. The specific technical details of the decoder LLR weight acquisition method can be referred to the discussion of the above-mentioned embodiments and will not be repeated here.

[0064] The decoding method proposed in this application is based on the aforementioned decoder LLR weight acquisition method for decoding, thereby overcoming the technical defects of the existing simplified model scheme that has a large performance loss under complex channel conditions and the fixed weight value scheme has a narrow adaptation range and often cannot fully release the performance, thereby ensuring the optimal decoding performance of the decoder.

[0065] An embodiment of the present application further provides a decoder LLR weight acquisition system, which includes at least three modules: a noise variance estimation value acquisition module, an equivalent power estimation value acquisition module, and an LLR weight acquisition module.

[0066] The noise variance estimation value acquisition module is used to acquire the noise variance estimation value of the received signal through the difference between the channel estimation values ​​of two adjacent symbols of the received signal.

[0067] The equivalent power estimation value acquisition module is used to acquire the equivalent power estimation value of the received signal using the amplitude value of the channel estimation value of the symbol of the received signal.

[0068] The LLR weight acquisition module is configured to obtain the LLR weight based on a ratio of an equivalent power estimation value of the received signal to a noise variance estimation value of the received signal.

[0069] The specific technical details and corresponding technical effects of the decoder LLR weight acquisition system can also be referred to the relevant discussion in the aforementioned decoder LLR weight acquisition method embodiment, and will not be repeated here.

[0070] An embodiment of the present application further provides a decoding system, which can execute the aforementioned decoding method for decoding.

[0071] The specific technical details and corresponding technical effects of the decoding system can also be referred to the relevant discussion in the above-mentioned embodiment of the decoding method, and will not be repeated here.

[0072] Figure 3 The following schematically shows a block diagram of an electronic device suitable for implementing the decoder LLR weight acquisition method and / or decoding method described above according to an embodiment of the present application. Figure 3 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0073] like Figure 3 As shown, the electronic device 1000 described in this embodiment includes: a processor 1001, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage part 1008 into a random access memory (RAM) 1003. The processor 1001 may include, for example, a general-purpose microprocessor (such as a CPU), an instruction set processor and / or a related chipset and / or a special-purpose microprocessor (for example, an application-specific integrated circuit (ASIC)), etc. The processor 1001 may also include an on-board memory for caching purposes. The processor 1001 may include a single processing unit or multiple processing units for executing different actions of the decoder LLR weight acquisition method and / or decoding method flow according to an embodiment of the present application.

[0074] RAM 1003 stores various programs and data required for the operation of system 1000. Processor 1001, ROM 1002, and RAM 1003 are connected to each other via bus 1004. Processor 1001 executes the programs in ROM 1002 and / or RAM 1003 to perform various operations of the decoder LLR weight acquisition method and / or decoding method process according to the embodiments of the present application. It should be noted that the programs may also be stored in one or more memories other than ROM 1002 and RAM 1003. Processor 1001 may also execute the programs stored in the one or more memories to perform various operations of the decoder LLR weight acquisition method and / or decoding method process according to the embodiments of the present application.

[0075] According to an embodiment of the present application, electronic device 1000 may further include an input / output (I / O) interface 1005, which is also connected to bus 1004. System 1000 may also include one or more of the following components connected to I / O interface 1005: an input section 1006 including a keyboard, mouse, etc.; an output section 1007 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and speakers; a storage section 1008 including a hard disk; and a communication section 1009 including a network interface card such as a LAN card or a modem. Communication section 1009 performs communication processing via a network such as the Internet. Drive 1010 is also connected to I / O interface 1005 as needed. Removable media 1011, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed in drive 1010 as needed, so that computer programs read from the removable media can be installed into storage section 1008 as needed.

[0076] According to an embodiment of the present application, the decoder LLR weight acquisition method and / or decoding method process can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable storage medium, and the computer program contains program code for executing the decoder LLR weight acquisition method and / or decoding method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network via the communication section 1009 and / or installed from the removable medium 1011. When the computer program is executed by the processor 1001, the above-mentioned functions defined in the system of the embodiment of the present application are performed. According to an embodiment of the present application, the systems, devices, means, modules and / or units described above can be implemented by computer program modules.

[0077] Embodiments of the present application also provide a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments, or may exist independently and not be incorporated into the device / apparatus / system. The computer-readable storage medium carries one or more programs, which, when executed, implement the decoder LLR weight acquisition method and / or decoding method steps according to the embodiments of the present application.

[0078] According to an embodiment of the present application, the computer-readable storage medium may be a non-volatile computer-readable storage medium, for example, it may include but is not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In an embodiment of the present application, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device. For example, according to an embodiment of the present application, the computer-readable storage medium may include one or more memories other than the ROM 1002 and / or RAM 1003 described above.

[0079] It should be noted that the functional modules in the various embodiments of the present application can be integrated into a processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product.

[0080] The flowcharts and / or block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods or computer program products according to various embodiments of the present application. In this regard, each box in the flowchart and / or block diagram can represent a module, a program segment or a part of code, and a part of the above-mentioned module, program segment or code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. It should also be noted that each box in the block diagram or flowchart, and the combination of the boxes in the block diagram or flowchart, can be implemented by a special hardware-based system that performs the specified function or operation, or can be implemented by a combination of special hardware and computer instructions.

[0081] Those skilled in the art will appreciate that the technical features described in the various embodiments and / or claims of this application may be combined and / or coupled in various ways, even if such combinations and / or couplings are not explicitly described in this application. In particular, without departing from the spirit and teachings of this application, the technical features described in the various embodiments and / or claims of this application may be combined and / or coupled in various ways, and all such combinations and / or couplings fall within the scope of this application.

[0082] Although the present application has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made to the present application without departing from the spirit and scope of the present application as defined by the appended claims and their equivalents. Therefore, the scope of the present application should not be limited to the above-described embodiments, but should be determined not only by the appended claims but also by the equivalents of the appended claims.

Claims

1. A decoder LLR weight acquisition method, characterized in that: include: Obtaining a noise variance estimation value of the received signal by using a difference between channel estimation values ​​of two adjacent symbols of the received signal; Obtaining an equivalent power estimation value of the received signal using an amplitude value of a channel estimation value of a symbol of the received signal; The LLR weight is obtained based on a ratio of an equivalent power estimate of the received signal to a noise variance estimate of the received signal.

2. The decoder LLR weight acquisition method according to claim 1, wherein: The formula for obtaining the LLR weight includes: ； in, represents the LLR weight; p represents the equivalent power estimation value of the received signal; represents an estimated value of the noise variance of the received signal; Represents a constant.

3. The decoder LLR weight acquisition method according to claim 2, wherein: The formula for obtaining the noise variance estimate of the received signal includes: ； The formula for obtaining the equivalent power estimate of the received signal includes: ； in, A channel estimate value representing symbol n of the received signal; Indicates the symbol of the mean value; Indicates the absolute value symbol.

4. A decoding method, characterized in that: The decoding method can perform decoding based on the decoder LLR weight acquisition method according to any one of claims 1 to 3.

5. A decoder LLR weight acquisition system, characterized in that: include: A noise variance estimation value acquisition module is used to obtain a noise variance estimation value of a received signal by using a difference between channel estimation values ​​of two adjacent symbols of the received signal; An equivalent power estimation value acquisition module, configured to acquire an equivalent power estimation value of the received signal using an amplitude value of a channel estimation value of a symbol of the received signal; The LLR weight acquisition module is configured to obtain the LLR weight based on a ratio of an equivalent power estimate of the received signal to a noise variance estimate of the received signal.

6. The decoder LLR weight acquisition system according to claim 5, wherein: The formula for obtaining the LLR weight includes: ； in, represents the LLR weight; p represents the equivalent power estimation value of the received signal; represents an estimated value of the noise variance of the received signal; Represents a constant.

7. The decoder LLR weight acquisition system according to claim 6, wherein: The formula for obtaining the noise variance estimate of the received signal includes: ； The formula for obtaining the equivalent power estimate of the received signal includes: ； in, A channel estimate value representing symbol n of the received signal; Indicates the symbol of the mean value; Indicates the absolute value symbol.

8. An electronic device, characterized in that: The method comprises at least one processing unit and at least one storage unit, wherein the storage unit stores a computer program. When the computer program is executed by the processing unit, the processing unit is enabled to perform the steps of the decoder LLR weight acquisition method according to any one of claims 1 to 3 and / or to perform the steps of the decoding method according to claim 4.

9. A storage medium, characterized in that: It stores a computer program that can be executed by an access authentication device. When the computer program is run on the access authentication device, the access authentication device is able to execute the steps of the decoder LLR weight acquisition method described in any one of claims 1 to 3 and / or the steps of the decoding method described in claim 4.

Images