CN108242978A - Interpretation method, device, spectrum detector and storage medium - Google Patents
Interpretation method, device, spectrum detector and storage medium Download PDFInfo
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Abstract
The present invention relates to interpretation method, device, spectrum detector and storage mediums, belong to signal processing technology field.The interpretation method includes：Receive radio signal；Can coding mode be identified used by judging the radio signal based on presetting method；When to be, the corresponding decoded mode of coding mode used by can judgement be found with the radio signal；When to be, based on the decoded mode to the radio signal into row decoding.It can carry out effectively identification to the signal of the unknown coding mode received and search corresponding decoded mode to go to decode by this method, read the useful information carried in the signal, and no longer it is that cooperation recipient directly uses known decoded mode to the signal received into directly into row decoding, it greatly solves under current complex electromagnetic environment, the problem of monitoring/monitoring technology Shortcomings of radio.
Description
Technical Field
The invention belongs to the technical field of signal processing, and particularly relates to a decoding method, a decoding device, a spectrum detector and a storage medium.
Background
Coding can be divided into source coding and channel coding, and the goal of source coding is to reduce redundancy of the source, to transmit more efficiently and economically, and its most common application is compression. In contrast, channel coding is to improve interference resistance and error correction capability by adding redundancy, such as check codes, to combat noise and attenuation in the channel. The decoding corresponding to the coding is the inverse process of the coding, and simultaneously, the noise mixed in the bit stream in the transmission process is removed.
Most of the current encoding is based on the convention between the sender and the receiver, in other words, both parties predetermine the encoding type in advance and know the decoding method accordingly, the sender encodes the signal according to the predetermined convention when sending the signal, and the receiver decodes the signal based on the known decoding method after receiving the signal.
Disclosure of Invention
In view of the above, the present invention provides a decoding method, an apparatus, a spectrum detector and a storage medium, so as to effectively solve the problem that the radio monitoring/monitoring technology is insufficient in the current complex electromagnetic environment.
The embodiment of the invention is realized by the following steps:
in a first aspect, an embodiment of the present invention provides a decoding method, including: receiving a radio signal; judging whether the coding mode adopted by the radio signal can be identified or not based on a preset method; if so, judging whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found; if so, the radio signal is decoded based on the decoding method.
In a second aspect, an embodiment of the present invention further provides a decoding apparatus, including: a receiving module for receiving a radio signal; the first judgment module judges whether the coding mode adopted by the radio signal can be identified based on a preset method; the second judgment module judges whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found; and the selecting module is used for decoding the radio signal based on the decoding mode.
In a third aspect, an embodiment of the present invention further provides a spectrum detector, including: a processor and a memory, the processor coupled with the memory; the memory is used for storing programs; the processor is used for calling a program stored in the memory and executing the decoding method.
In a fourth aspect, an embodiment of the present invention further provides a storage medium, where the computer-readable storage medium stores program code executable by a processor in a computer, and the computer-readable storage medium includes a plurality of instructions configured to cause the processor to execute the decoding method.
Compared with the prior art, the decoding method, the decoding device, the spectrum detector and the storage medium provided by the embodiment of the invention greatly solve the problem that the radio monitoring/monitoring technology is insufficient in the current complex electromagnetic environment. Further, in the radio spectrum monitoring and information countermeasure under the non-cooperative communication condition, the non-cooperative receiving party cannot predict the coding mode used by the received radio signal, so that whether the coding mode of the signal can be identified is judged based on a preset method, if so, whether a decoding mode matched with the coding mode can be found is judged, and if so, the decoding mode is selected to decode so as to read the useful information carried in the signal, and the decoding is not performed on the known signal.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the embodiments of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts. The above and other objects, features and advantages of the present invention will become more apparent from the accompanying drawings. Like reference numerals refer to like parts throughout the drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
Fig. 1 shows a block diagram of a spectrum detector according to an embodiment of the present invention.
Fig. 2 shows a flowchart of a decoding method according to a first embodiment of the present invention.
Fig. 3 shows a flowchart of a method of step S102 in fig. 2 according to an embodiment of the present invention.
Fig. 4 shows a flowchart of a method of the interpretation process provided by the embodiment of the present invention.
Fig. 5 is a schematic diagram illustrating channel error correction decoding based on a hybrid ARQ mechanism according to an embodiment of the present invention.
Fig. 6 shows a flowchart of a multiple error correction decoding algorithm provided by an embodiment of the present invention.
Fig. 7 shows a flowchart of a decoding method according to a second embodiment of the present invention.
Fig. 8 is a block diagram of a decoding apparatus according to a third embodiment of the present invention.
Fig. 9 is a block diagram illustrating a second determining module in fig. 8 according to an embodiment of the present invention.
Detailed Description
In order to make the objects, 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 with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it should be noted that the terms "first", "second", "third", and the like are used only for distinguishing the description, and are not intended to indicate or imply relative importance.
As shown in fig. 1, fig. 1 is a block diagram illustrating a spectrum detector 100 according to an embodiment of the present invention. The spectrum sensor 100 includes: decoding device 110, memory 120, memory controller 130, and processor 140.
The memory 120, the memory controller 130, and the processor 140 are electrically connected to each other directly or indirectly to realize data transmission or interaction. For example, the components may be electrically connected to each other via one or more communication buses or signal lines. The decoding device 110 includes at least one software functional module that can be stored in the memory 120 in the form of software or firmware (firmware) or is fixed in an Operating System (OS) of the spectrum detector 100. The processor 140 is used for executing executable modules stored in the memory 120, such as software functional modules or computer programs included in the decoding device 110.
The Memory 120 may be, but is not limited to, a Random Access Memory (RAM), a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Read-Only Memory (EPROM), an electrically Erasable Read-Only Memory (EEPROM), and the like. The memory 120 is used for storing a program, and the processor 140 executes the program after receiving an execution instruction, and a method executed by the spectrum detector 100 defined by a process disclosed in any embodiment of the invention described later may be applied to the processor 140, or implemented by the processor 140.
The processor 140 may be an integrated circuit chip having signal processing capabilities. The processor may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), a Graphics Processing Unit (GPU), and the like; but may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. The various methods, steps and logic blocks disclosed in the embodiments of the present invention may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
First embodiment
Referring to fig. 2, a decoding method applied to the spectrum detector 100 according to an embodiment of the present invention is described below with reference to fig. 2.
Step S101: a radio signal is received.
The spectrum detector receives the detected radio signal when detecting the radio signal.
Step S102: and judging whether the coding mode adopted by the radio signal can be identified or not based on a preset method.
After receiving a radio signal, to further know the content contained in the signal, it is first necessary to demodulate the received radio signal to obtain a demodulated signal, and then decode the demodulated signal. The received radio signal is not a signal coded according to a coding mode agreed in advance, but an unknown signal of the coding mode used by the received radio signal cannot be predicted. Therefore, it is necessary to determine whether or not the encoding method used for the radio signal can be recognized. This step is further illustrated by the method flow diagram shown in fig. 3.
Step S201: and preprocessing the radio signal to obtain a preprocessed signal.
After receiving a radio signal (carrier signal), the received radio signal (carrier signal) needs to be demodulated first to obtain a demodulated radio signal, i.e. a channel coding or a communication protocol. The demodulated radio signal (channel code or communication protocol) is then interpreted to obtain an interpreted signal, i.e. a signal obtained by removing the redundancy code from the demodulated radio signal. Namely, the pretreatment comprises the following steps: demodulation and interpretation processes.
For ease of understanding, the procedure of interpretation will be described below with reference to the flowchart shown in fig. 4.
Step S301: a demodulated radio signal is acquired.
Step S302: it is determined whether the communication protocol used by the demodulated radio signal can be identified.
After the demodulated radio signal (i.e., the channel code) is obtained, a communication protocol used for the channel code (i.e., the demodulated radio signal) needs to be identified, for example, feature parameters such as a linear constraint relationship, a code weight, and a hamming distance are extracted by using a priori conditions (e.g., a coding mode), and then the extracted feature parameters are identified by using a feature parameter library of a known channel coding type. If the identification is available, executing step S303; if the identification is not possible, the process is ended.
Step S303: and judging whether an interpretation mode corresponding to the communication protocol adopted by the demodulated radio signal can be found.
If the communication protocol used by the channel code (demodulated radio signal) can be identified, it is determined that the interpretation method corresponding to the communication protocol used by the channel code can be found, and if the interpretation method can be found, step S304 is executed; if not, the method is ended.
Step S304: interpreting the demodulated radio signal based on the interpretation.
When the interpretation mode corresponding to the communication protocol adopted by the radio signal can be found, the signal is interpreted based on the found interpretation mode to obtain an interpreted signal, namely, a signal with redundant codes removed, namely, source coding.
Step S202: and extracting characteristic quantity representing the coding mode based on the preprocessed signal.
Extracting a feature quantity of the demodulated and interpreted preprocessed signal, wherein the feature quantity can be any feature quantity capable of characterizing a coding mode, such as: classification features based on frame alignment parameters, classification features based on error correction coding, classification features based on interleaving parameters, and the like.
Wherein the frame positioning parameters include: the length of the frame, the start of each frame of data, and the frame synchronization code.
Wherein the error correction coding includes: binary cyclic codes, Reed-Solomon codes (Reed-Solomon), low density parity check codes, convolutional codes, and the like.
Wherein the interleaving parameters include: packet interleaving parameters and convolutional interleaving parameters.
Step S203: and judging whether the characteristic quantity can be identified based on a preset method.
And after the characteristic quantity of the signal is obtained, selecting a method from a method database to identify the coding mode corresponding to the characteristic quantity, and if the method cannot identify the coding mode corresponding to the characteristic quantity, selecting a method from the rest methods to identify the coding mode corresponding to the characteristic quantity until the coding mode corresponding to the characteristic quantity is identified or all the methods in the method database are selected. The preset method may be an identification algorithm based on frame positioning parameters, an identification algorithm based on error correction coding, and/or an identification algorithm based on interleaving parameters. That is, in the case of identifying the feature amount, it may be based on one identification algorithm as described above, or it may be a combination of several identification algorithms, for example, an identification algorithm based on the frame alignment parameter, an identification algorithm using the error correction code, and an identification algorithm using the interleaving parameter.
When judging whether the characteristic quantity can be identified based on a preset method, if so, executing step S103, and if not, returning to the step of interpreting, namely, executing step S201, until the number of times of being unidentifiable reaches a preset threshold value, and ending. Step S103: and judging whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found.
When the coding scheme of the radio signal is identified, for example, RS code, convolutional code, Turbo code, LDPC code, RRNS code, Hamming code, and Nick Turbo Hamming code are used. And judging whether a decoding mode corresponding to the coding mode can be found. If the decoding method corresponding to the detected result can be found, go to step S104; if the decoding method corresponding to the code can not be found, the process is ended.
Step S104: and decoding the radio signal based on the decoding mode.
When a decoding mode corresponding to the coding mode adopted by the radio signal can be found, the signal is decoded based on the found decoding mode to obtain a decoded signal, so as to carry out subsequent processing. Further, in order to improve the decoding accuracy, multiple error correction decoding algorithms can be combined to decode the radio signal. For convenience of understanding, taking a 16-bit sound signal adopting a DQPSK modulation mode as an example, according to different communication processes, the signal is transmitted in three frame formats, namely a supervisory frame, an acceptance frame and an information frame, wherein the information frame contains data information for message recovery, and total 264 bits, and 48-bit frame number information, 192-bit data information and 24-bit CRC check information are sequentially included. Since two coding schemes are used for such signals during channel transmission, namely Cyclic Redundancy Check (CRC) (216, 192) for error detection and extended Golay (24, 12) for error correction. Wherein the (216, 192) CRC calculation syndrome is:
go(x)＝x24+x7+x2+x+1 (1)
the (24, 12) extended Golay code means that 1-bit even check bits are added on the basis of the (23, 12) Golay code, and the calculation syndrome of the (23, 12) Golay code is as follows:
g1(x)＝x11+x9+x7+x6+x5+x+1 (2)
it can be easily seen that only the CRC check is performed on 192-bit data information within one information frame without error correction processing. Therefore, for short-wave channels with poor quality, a very high bit error rate is brought, and the final message recovery rate is directly influenced.
Further analyzing the signal communication characteristic, it can be found that the signal is decoded by using the ARQ mechanism to perform channel error correction. In particular, the signal employs a hybrid ARQ mechanism based on check retransmission combined with a limited reception buffer, as shown in fig. 5. Wherein, P0 represents (216, 192) CRC code, P1 represents (24, 12) extended Golay code, Head represents 48 bits corresponding to frame number, and Data represents 192 bits corresponding to Data information.
For each frame of Data information, a sender firstly performs CRC encoding on Data to obtain a 24-bit check bit P0 (Data); then sending out the frame; the receiver calculates the syndrome according to equation (1), if the syndrome is 0, the received information is considered to have no error, if the syndrome is not 0, the receiver stores the frame data first and sends a NAK message to the sender; after receiving NAK, the sender still performs CRC coding on Data to obtain P0(Data), then performs (24, 12) extended Golay coding on Data and P0(Data) to obtain P1(Data) and P1(P0(Data)), and sends the Data to the receiver; if the receiver calculates the syndrome according to the formula (1) and the result is still not 0, the receiver continues to send a NAK message to the sender; at this time, the sender sends Data, P0(Data), and so on to the receiver.
Therefore, considering that the short-wave channel is poor in transmission quality and high in error rate, the error correction capability of the error correction code needs to be fully utilized as much as possible, and the decoding accuracy can be improved based on a multiple error correction decoding algorithm. The flowchart of the multiple error correction decoding algorithm is shown in fig. 6.
The multiple error correction decoding refers to three methods, namely directly using a CRC check result, using retransmission frame data + check error correction, and using different decoding algorithms data + data error correction. The term "data + check" error correction means that corresponding contents of a plurality of retransmission frames can be combined with each other for the same frame data, that is, a plurality of data pairs including data information and check information are formed, and extended Golay decoding is performed (24, 12) for each data pair. By adopting the strategy, the decoding accuracy can be improved to 100% from the original 25% in the best case for the same frame data. The data + data error correction means that under the condition that a retransmission frame does not exist, three types of decoding results obtained by a multi-strategy joint anti-fading non-partner blind receiving algorithm are fused, the difference and the similarity of information bits at the same position are compared, when the number of different bits is smaller than a given threshold value, all different bits are exhausted, the syndrome of each group of combinations is respectively calculated, and if CRC (cyclic redundancy check) passes, the error correction decoding is considered to be successful.
The multi-strategy joint anti-fading non-partner blind receiving algorithm comprises the following steps: symbol rate estimation based on the squared spectrum of the signal envelope, non-data aided carrier frequency offset maximum likelihood estimation and non-data aided carrier initial phase estimation.
For short wave signals with low signal-to-noise ratio under non-cooperative blind receiving conditions, a non-data-aided forward estimation algorithm can be adopted when carrier synchronization parameters (carrier frequency and carrier phase) are estimated, namely parameters are directly estimated from samples of received signals based on a certain criterion (for example, a maximum likelihood criterion). For signal capture and identification under the condition of blind reception of a non-partner, firstly, carrying out coarse estimation on carrier frequency offset based on a detection signal to realize rapid capture of a carrier, and limiting an estimation error within +/-0.5 Hz; then carrying out down-conversion and matched filtering processing; and then, carrying out fine estimation on symbol rate, carrier frequency offset and carrier phase aiming at each path of subcarrier to obtain the demodulation information bit stream of each path.
Considering that the influence of fading on the short-wave burst signal is random, fading may occur at the head of the burst, or may occur in the middle or at the tail of the burst. At this time, if the demodulation parameters are estimated in a single manner (for example, demodulation parameter estimation is performed using burst header data all together), the result is likely to be inaccurate. Aiming at the problem, the invention provides a multi-strategy joint anti-fading non-cooperative blind receiving algorithm which starts from different positions of burst signals, respectively carries out demodulation processing, then carries out fusion judgment on the result, respectively estimates demodulation parameters by utilizing the head data, the middle data and the tail data of the burst, and determines the optimal demodulation result by combining with a CRC (cyclic redundancy check) check result. Further, regarding a certain burst signal of a certain path of sub-carrier, dividing the burst into a head part, a middle part and a tail part for consideration, respectively performing demodulation parameter estimation, and determining whether the data frame is correctly demodulated through CRC check. By using the strategy, the influence of the short-wave channel fading characteristic on signal blind reception can be effectively reduced.
1) Symbol rate estimation based on the squared spectrum of the signal envelope:
in this case, the received signal symbol rate is deviated from the theoretical value in consideration of a certain error in the crystal oscillators of both the communication parties. This requires symbol rate estimation prior to symbol timing estimation, using a symbol rate estimation algorithm based on the squared spectrum of the signal envelope.
For observed data x (t) in white gaussian noise w (t), the following:
wherein, anAnd bnRepresenting the real and imaginary parts, T, of the information symbolbIs a symbol period, fcIs the carrier frequency. Firstly, Hilbert conversion is carried out to obtain an analytic signalThen calculateThe squared envelope signal z (t), i.e.:
by appropriate derivation, one can obtain:
wherein,and the Fourier transform of u (t) can be expressed as:
thus, the discrete spectral lines corresponding to the symbol rate can be detected from the fourier transform magnitude spectrum of z (t).
2) Non-data-aided maximum likelihood estimation:
and carrying out fine estimation on the carrier frequency offset of the quasi-baseband signal subjected to the rough frequency offset estimation, the down-conversion and the matched filtering by adopting a non-data-aided maximum likelihood estimation algorithm.
Assume that the received data for which accurate symbol synchronization has been obtained is:
wherein, akIs the independent and equally distributed equivalent DQPSK data (assuming that the signal is a 16-tone signal adopting a DQPSK debugging mode), T is a symbol period, feIs the unknown carrier frequency offset, θ0Is the unknown carrier phase, nkIs complex white Gaussian noise with the variance of sigma2. By proper derivation, x can be knownkThe log-likelihood function of (a) is:
where N represents the data symbol length and has:
wherein,represents a pair function Y (a)k…) of akAnd taking an average value. By substituting equation (2) for equation (1) and omitting irrelevant terms, we can obtain:
for a 2 pi/M rotationally symmetric constellation, we can further simplify to:
thereby obtaining the maximum likelihood estimation of the carrier frequency offset as:
then order:
for the derivation of the above equation, only the necessary condition that the derivative is 0, i.e. the imaginary part is 0, is analyzed, i.e.:
wherein the autocorrelation function r (k) is defined as:
and is provided withIt can be seen that the autocorrelation function r (k) contains all the information of the carrier frequency offset, and then the classical M is used&The M algorithm estimates the frequency offset, i.e.:
wherein the weight w (k) is:
3) non-data-aided carrier initial phase estimation:
if the burst time is short, it is sufficient to perform phase estimation once in a burst time, but if the burst time is long, it is not reasonable to assume that there is no frequency offset in a burst time, and at this time, the whole burst needs to be divided into several time periods, and it is assumed that there is no frequency offset in each period, and phase offset estimation is performed for each segment of data. This processing method may generate phase jumps from segment to segment, i.e., phase ambiguity from segment to segment.
To solve this problem, a carrier phase estimation value is obtained based on a V & V algorithm. The implementation process of the V & V algorithm can be summarized as follows: nonlinear de-modulation transforms-sum of the real and imaginary signals, respectively-compute phase. If the burst is short, the value is considered as the carrier phase estimation result of the burst; if the burst is longer, it is determined whether there is a phase jump and the phase jump is further eliminated.
Let V&The phase estimation value of the ith section of data output by the V algorithm isThe value range is + -pi/M, M represents the modulation order of DQPSK signal, and the actual phase isk is one of 0,1, …, M-1. Suppose the actual phase of the i-1 th segment signal within a burst is:
then, the actual phase of the i-th segment signal:
must be the closestThe phase value of (a), i.e.:
by adopting the method, the probability of continuous phase jump can be effectively reduced, and the anti-noise performance of the algorithm is improved. Second embodiment
As an implementation manner, referring to fig. 7, the present embodiment provides a decoding method applied to the spectrum detector 100, and the steps included in the decoding method will be described with reference to fig. 7.
Step S401: a radio signal is received.
The step is the same as step S101, and please refer to step S101 for details.
Step S402: and judging whether the coding mode adopted by the radio signal can be identified or not based on a preset method.
The step is the same as step S102, and please refer to step S102 specifically, wherein, if the coding method adopted by the radio signal cannot be identified, step S405 is executed.
Step S403: and judging whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found.
The step is the same as step S103, and please refer to step S103 for further description.
Step S404: and decoding the radio signal based on the decoding mode.
The step is the same as step S104, and please refer to step S104 for specific description.
Step S405: and recording or sampling and storing the radio signal.
When the coding mode adopted by the radio signal cannot be identified, the radio signal is recorded or sampled and stored to be used as a subsequent signal coding analysis material, so that a new identification mode is developed for identifying the radio signal in the subsequent process.
Third embodiment
The embodiment of the invention also provides a decoding device, as shown in fig. 8. The decoding apparatus 110 includes: the device comprises a receiving module 111, a first judging module 112, a second judging module 113, a selecting module 114 and a storing module 115.
The receiving module 111 is configured to receive a radio signal.
The first determining module 112 is configured to determine whether the encoding method adopted by the radio signal can be identified based on a preset method. Further, as shown in fig. 9, the first determining module 112 further includes: a preprocessing submodule 1121, a feature extraction submodule 1122 and a judgment submodule 1123.
The preprocessing submodule 1121 is configured to preprocess the radio signal to obtain a preprocessed signal.
And a feature extraction submodule 1122, configured to extract a feature quantity characterizing the encoding mode based on the preprocessed signal.
A judgment sub-module 1123 configured to judge whether the feature amount can be identified based on a preset method.
The second determining module 113 is configured to determine whether a decoding manner corresponding to the encoding manner adopted by the radio signal can be found.
A selecting module 114, configured to decode the radio signal based on the decoding manner.
And the storage module 115 is configured to record or sample and store the radio signal.
It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.
The decoding apparatus 110 provided in the embodiment of the present invention has the same implementation principle and technical effect as the foregoing method embodiments, and for the sake of brief description, reference may be made to the corresponding contents in the foregoing method embodiments for the parts of the apparatus embodiments that are not mentioned.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other ways. The apparatus embodiments described above are merely illustrative, and for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
In addition, the functional modules in the embodiments of the present invention may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
The functions, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes. It is to be noted that, in the present invention, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A decoding method, comprising:
receiving a radio signal;
judging whether the coding mode adopted by the radio signal can be identified or not based on a preset method;
if so, judging whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found;
if so, the radio signal is decoded based on the decoding method.
2. The method of claim 1, wherein determining whether the encoding scheme adopted by the radio signal can be identified based on a predetermined method comprises:
preprocessing the radio signal to obtain a preprocessed signal;
extracting characteristic quantity representing a coding mode based on the preprocessed signal;
and judging whether the characteristic quantity can be identified based on a preset method.
3. The method according to claim 2, wherein determining whether the feature quantity can be recognized based on a preset method includes:
and judging whether the characteristic quantity can be identified or not based on an identification algorithm of the frame positioning parameter, an identification algorithm of the error correction coding and/or an identification algorithm of the interleaving parameter.
4. The method of claim 1, wherein when the encoding scheme employed by the radio signal cannot be identified, the method further comprises:
and recording or sampling and storing the radio signal.
5. A decoding apparatus, comprising:
a receiving module for receiving a radio signal;
the first judgment module judges whether the coding mode adopted by the radio signal can be identified based on a preset method;
the second judgment module judges whether a decoding mode corresponding to the coding mode adopted by the radio signal can be found;
and the selecting module is used for decoding the radio signal based on the decoding mode.
6. The decoding apparatus according to claim 5, wherein the first determining module comprises:
the preprocessing submodule is used for preprocessing the radio signal to obtain a preprocessed signal;
the characteristic extraction module is used for extracting characteristic quantity representing a coding mode based on the preprocessed signal;
and the judging submodule is used for judging whether the characteristic quantity can be identified based on a preset method.
7. The decoding device according to claim 6, wherein the determining sub-module is further configured to determine whether the feature quantity can be identified based on a frame alignment parameter identification algorithm, an error correction coding identification algorithm, and/or an interleaving parameter identification algorithm.
8. The decoding apparatus according to claim 5, wherein the encoding apparatus further comprises: and the storage module is used for recording or sampling and storing the radio signal.
9. A spectrum detector, comprising: a processor and a memory, the processor coupled with the memory;
the memory is used for storing programs;
the processor is used for calling a program stored in the memory and executing the decoding method of any one of claims 1-4.
10. A storage medium storing program code executable by a processor in a computer, the computer-readable storage medium comprising instructions configured to cause the processor to perform the method of decoding as claimed in any one of claims 1-4.
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| CN201810021315.2A CN108242978A (en) | 2018-01-10 | 2018-01-10 | Interpretation method, device, spectrum detector and storage medium |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110474713A (en) * | 2019-07-01 | 2019-11-19 | 华南师范大学 | A kind of communication system for improving RRNS code coding/decoding process |
| CN112689048A (en) * | 2020-12-24 | 2021-04-20 | 北京浪潮数据技术有限公司 | DTMF signal decoding method, device, equipment and storage medium |
| CN113037663A (en) * | 2021-03-09 | 2021-06-25 | 山东大学 | Improved code element rate estimation algorithm suitable for non-constant envelope signal |
| CN115567165A (en) * | 2022-10-18 | 2023-01-03 | 天津津航计算技术研究所 | Coding error correction method, system, terminal equipment and readable storage medium |
-
2018
- 2018-01-10 CN CN201810021315.2A patent/CN108242978A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110474713A (en) * | 2019-07-01 | 2019-11-19 | 华南师范大学 | A kind of communication system for improving RRNS code coding/decoding process |
| CN110474713B (en) * | 2019-07-01 | 2022-05-03 | 华南师范大学 | Communication system for improving coding and decoding process of RRNS code |
| CN112689048A (en) * | 2020-12-24 | 2021-04-20 | 北京浪潮数据技术有限公司 | DTMF signal decoding method, device, equipment and storage medium |
| CN113037663A (en) * | 2021-03-09 | 2021-06-25 | 山东大学 | Improved code element rate estimation algorithm suitable for non-constant envelope signal |
| CN115567165A (en) * | 2022-10-18 | 2023-01-03 | 天津津航计算技术研究所 | Coding error correction method, system, terminal equipment and readable storage medium |
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