CN113692045B - Frame synchronization method and system under large frequency bias - Google Patents
Frame synchronization method and system under large frequency bias Download PDFInfo
- Publication number
- CN113692045B CN113692045B CN202110974427.1A CN202110974427A CN113692045B CN 113692045 B CN113692045 B CN 113692045B CN 202110974427 A CN202110974427 A CN 202110974427A CN 113692045 B CN113692045 B CN 113692045B
- Authority
- CN
- China
- Prior art keywords
- signal
- frame synchronization
- complete burst
- burst signal
- conjugate multiplication
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 51
- 238000004364 calculation method Methods 0.000 claims abstract description 22
- 238000012821 model calculation Methods 0.000 claims abstract description 18
- 238000007781 pre-processing Methods 0.000 claims abstract description 16
- 238000001914 filtration Methods 0.000 claims description 18
- 238000005070 sampling Methods 0.000 claims description 5
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 3
- 238000004422 calculation algorithm Methods 0.000 abstract description 24
- 238000001514 detection method Methods 0.000 abstract description 14
- 230000007547 defect Effects 0.000 abstract description 5
- 238000005457 optimization Methods 0.000 description 7
- 238000004891 communication Methods 0.000 description 4
- 238000004088 simulation Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W56/00—Synchronisation arrangements
- H04W56/001—Synchronization between nodes
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0602—Systems characterised by the synchronising information used
- H04J3/0617—Systems characterised by the synchronising information used the synchronising signal being characterised by the frequency or phase
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The invention discloses a frame synchronization method and a system under large frequency bias, which firstly generate a local pilot signal and receive an external intermediate frequency signal; preprocessing the received intermediate frequency signal, and then intercepting to form a section of complete burst signal containing pilot frequency symbol stream; based on the local pilot signal and the complete burst signal, performing conjugate multiplication model calculation, and then performing delay correlation model calculation on a conjugate multiplication model calculation result; and determining the frame head position in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization. The method has the advantages that the defect that the frequency offset capacity is small or the correlation peak is not sharp enough in the prior art is overcome, and a novel frame synchronization method is provided, and the method still has good detection performance under the condition of large frequency offset, and even under the condition of large frequency offset, the frame synchronization algorithm provided by the invention can still accurately detect the position of the frame head.
Description
Technical Field
The invention relates to the technical field of wireless communication, in particular to a frame synchronization method and system under large frequency offset.
Background
In a wireless communication system, signal transmission has time delay, and frame head positions need to be correctly captured to recover complete information of frames, so that a frame structure can be analyzed to obtain the required information, and a frame synchronization technology mainly completes arrival detection of the frames and determination of the frame head positions. In an actual communication environment, the two parties are usually in a motion state, such as walking, riding and the like, but the relative motion of the receiving and transmitting ends can cause a Doppler frequency shift phenomenon of a transmission signal, and the larger the relative speed is, the larger the frequency shift is. The frequency offset may cause a constellation of the signal to rotate, possibly resulting in missed or false detection of the frame header position. In the case of large frequency offsets, how to perform frame synchronization is a considerable problem.
The frame synchronization method in the prior art is mainly a correlation method, and the positions of correlation peaks in a correlation curve are frame head positions and can be divided into two types: (1) autocorrelation method: the method belongs to a frame synchronization method which is not assisted by data, and carries out autocorrelation operation on a received signal, and is an energy detection algorithm in fact; (2) a cross-correlation method: the method belongs to a data auxiliary method, and carries out cross-correlation operation on a received signal and a local sequence.
Both algorithms make use of the correlation of the signals, and the autocorrelation frame synchronization method has the advantages of no additional resources, large frequency offset tolerance, smooth variation of the autocorrelation curve near the peak and poor detection performance. The cross-correlation algorithm has the advantages that the positions of frames can be roughly locked at the same time after judging that the frames arrive, and the cross-correlation algorithm has the defects that the influence of frequency deviation is larger, and the performance is poorer.
Disclosure of Invention
The invention aims to solve the technical problems that the autocorrelation curve of the frame synchronization method in the prior art changes gently near the peak value, the position of the frame can be roughly locked after the frame arrives, but the detection performance is greatly influenced by the frequency offset, the frequency offset capacity is small, the correlation peak is not sharp enough, and the position of the frame is difficult to lock under the condition of large frequency offset; the larger the frequency offset, the worse the performance; the invention aims to provide a frame synchronization method and a frame synchronization system under large frequency deviation so as to solve the technical problems.
The invention is realized by the following technical scheme:
the scheme provides a frame synchronization method under large frequency bias, which comprises the following steps:
s1, generating a local pilot signal and receiving an external intermediate frequency signal;
S2, preprocessing the received intermediate frequency signal, and then intercepting to form a section of complete burst signal containing pilot frequency symbol stream;
S3, performing conjugate multiplication model calculation on the local pilot signal and the complete burst signal, and performing delay correlation model calculation on a conjugate multiplication model calculation result;
s4, determining the frame head position in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization.
The further optimization scheme is that the preprocessing process in the step S2 comprises the following steps: and mixing, extracting and filtering the received intermediate frequency signals to form baseband IQ data, and intercepting the baseband IQ data to form a section of complete burst signal containing pilot frequency symbol stream.
The further optimization scheme is that the filtering processing comprises low-pass filtering and matched filtering, the matched filtering adopts a root raised cosine filter, and the roll-off factor takes a value between 0.2 and 0.5.
In a further optimization scheme, the baseband IQ data comprises a pilot frequency part and a data part, wherein the pilot frequency part is taken from PN or gold sequences.
The further optimization scheme is that the method for calculating the conjugate multiplication model based on the local pilot signal and the complete burst signal comprises the following steps:
Acquiring a pilot symbol with a length of N from a local pilot signal as a local pilot symbol stream for frame synchronization; and sliding the sliding window along the complete burst signal, taking N signal points backwards from the current position, and carrying out conjugate multiplication on the N signal points in the sliding window and N local pilot symbols in a one-to-one correspondence manner.
A further optimization is that the local pilot signal is expressed as: local= { l 1,l2,…,ln }; wherein the feature code l p＝eiπk, p=1, 2, …, n, k=0 or 1;
The external intermediate frequency signal is expressed as: rx= { r 1,r2,…,rm }, satisfying M > m·n+l, M representing the ratio of the sampling rate to the symbol rate, L being the sliding window length;
The complete burst signal is expressed as: { r k,rk+M·1,…,rk+M·(n-1) }, k=1, 2, …, L; step S3, performing conjugate multiplication operation on the complete burst signal and the local pilot signal to obtain:
the further optimization scheme is that the delay correlation model calculation process of the conjugate multiplication model calculation result is as follows:
and (3) performing delay autocorrelation operation on the result of conjugate multiplication operation, wherein the calculation formula of the correlation value when the delay window length is 1 and the current position is k is expressed as follows:
In the above formula, x represents a dot product, conj represents a conjugate, and sum represents a sum.
The further optimization scheme is that the method for determining the frame head position according to the calculation result of the delay correlation model comprises the following steps: and constructing a correlation curve graph, wherein the position of the peak value of the correlation value in the correlation curve graph is the frame head position.
Based on the frame synchronization method under the large frequency bias, the scheme also provides a frame synchronization system under the large frequency bias, which comprises the following steps: the device comprises a signal acquisition module, a preprocessing module, a calculation module and a frame head determination module;
The signal acquisition module is used for generating a local pilot signal and receiving an external intermediate frequency signal;
The preprocessing module is used for preprocessing the received intermediate frequency signal and then intercepting and forming a section of complete burst signal containing pilot frequency symbol stream;
the calculation module calculates a conjugate multiplication model based on the local pilot signal and the complete burst signal, and then calculates a delay correlation model of the calculation result of the conjugate multiplication model;
And the frame head determining module determines the position of the frame head in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization.
In an actual communication environment, the two parties are usually in a motion state, such as walking, riding and the like, but the relative motion of the receiving and transmitting ends can cause a Doppler frequency shift phenomenon of a transmission signal, and the larger the relative speed is, the larger the frequency shift is. The frequency offset can cause the constellation diagram of the signal to rotate, and can cause missing detection or false detection of the frame head position; the existing frame synchronization method mainly utilizes the correlation of signals, but the existing frame synchronization method has the defects of unobvious detection effect or larger influence of frequency offset: the autocorrelation frame synchronization method does not occupy extra resources and has larger frequency offset tolerance, but the autocorrelation curve changes smoothly near the peak value, and the detection performance is poor; the cross-correlation algorithm can roughly lock the position of the frame at the same time after judging that the frame arrives, but is greatly influenced by frequency offset, and the larger the frequency offset is, the worse the performance is. The frame synchronization method and the system provided by the scheme perform conjugate multiplication operation and delay correlation operation on the complete burst signal containing the pilot frequency symbol stream and the local pilot frequency symbol stream, and the peak position of the correlation value is regarded as the frame head position, so that the frame head position can be accurately determined, and the frame synchronization algorithm provided by the invention still has better detection performance under the condition of large frequency offset even under the condition of large frequency offset.
Compared with the prior art, the invention has the following advantages and beneficial effects:
The frame synchronization method and the system under the large frequency offset overcome the defects of small frequency offset capacity or insufficient sharp correlation peak in the prior art, and provide a novel frame synchronization method which still has better detection performance under the condition of large frequency offset, and even under the condition of large frequency offset, the frame synchronization algorithm provided by the invention can still accurately detect the frame head position.
Drawings
In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the drawings that are needed in the examples will be briefly described below, it being understood that the following drawings only illustrate some examples of the present invention and therefore should not be considered as limiting the scope, and that other related drawings may be obtained from these drawings without inventive effort for a person skilled in the art. In the drawings:
FIG. 1 is a flow chart of a frame synchronization method under a large frequency bias;
FIG. 2 is a schematic diagram of a burst signal format;
FIG. 3 is a graph of correlation for normalized frequency offset of 0 and signal to noise ratio of 0 dB;
FIG. 4 is a graph of correlation for a normalized frequency offset of 0 and a signal to noise ratio of 30 dB;
FIG. 5 is a graph showing correlation with normalized frequency offset of 0.001 and signal to noise ratio of 30 dB;
FIG. 6 is a graph of correlation for a normalized frequency offset of 0.01 and a signal to noise ratio of 30 dB;
Fig. 7 is a graph of correlation for a normalized frequency offset of 0.1 and a signal to noise ratio of 30 dB.
Detailed Description
For the purpose of making apparent the objects, technical solutions and advantages of the present invention, the present invention will be further described in detail with reference to the following examples and the accompanying drawings, wherein the exemplary embodiments of the present invention and the descriptions thereof are for illustrating the present invention only and are not to be construed as limiting the present invention.
The existing frame synchronization method mainly utilizes the correlation of signals, but the existing frame synchronization method has the defects of unobvious detection effect or larger influence of frequency offset: the autocorrelation frame synchronization method does not occupy extra resources and has larger frequency offset tolerance, but the autocorrelation curve changes smoothly near the peak value, and the detection performance is poor; the cross-correlation algorithm can roughly lock the position of the frame at the same time after judging that the frame arrives, but is greatly influenced by frequency offset, and the larger the frequency offset is, the worse the performance is; in view of this, the present invention proposes the following embodiments:
Example 1
As shown in fig. 1, the present embodiment provides a frame synchronization method under a large frequency offset, including the steps of:
s1, generating a local pilot signal and receiving an external intermediate frequency signal;
S2, preprocessing the received intermediate frequency signal, and then intercepting to form a section of complete burst signal containing pilot frequency symbol stream;
S3, performing conjugate multiplication model calculation on the local pilot signal and the complete burst signal, and performing delay correlation model calculation on a conjugate multiplication model calculation result;
s4, determining the frame head position in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization.
The preprocessing process in step S2 includes: and mixing, extracting and filtering the received intermediate frequency signals to form baseband IQ data, and intercepting the baseband IQ data to form a section of complete burst signal containing pilot frequency symbol stream.
The filtering treatment comprises low-pass filtering and matched filtering, the matched filtering adopts a root raised cosine filter, and the roll-off factor takes a value between 0.2 and 0.5.
The baseband IQ data comprises a pilot portion and a data portion, the pilot portion being taken from a PN or gold sequence.
The method for calculating the conjugate multiplication model based on the local pilot signal and the complete burst signal comprises the following steps:
Acquiring a pilot symbol with a length of N from a local pilot signal as a local pilot symbol stream for frame synchronization; and sliding the sliding window along the complete burst signal, taking N signal points backwards from the current position, and carrying out conjugate multiplication on the N signal points in the sliding window and N local pilot symbols in a one-to-one correspondence manner.
The local pilot signal is expressed as: local= { l 1,l2,…,ln }; wherein the feature code l p＝eiπk, p=1, 2, …, n, k=0 or 1;
the external intermediate frequency signal is expressed as: rx= { r 1,r2,…,rm }, satisfying M > m·n+l, M representing the ratio of the sampling rate to the symbol rate, L being the sliding window length;
The complete burst signal is expressed as: { r k,rk+M·1,…,rk+M·(n-1) }, k=1, 2, …, L; step S3, performing conjugate multiplication operation on the complete burst signal and the local pilot signal to obtain:
The delay correlation model calculation process for the conjugate multiplication model calculation result comprises the following steps:
and (3) performing delay autocorrelation operation on the result of conjugate multiplication operation, wherein the calculation formula of the correlation value when the delay window length is 1 and the current position is k is expressed as follows:
In the above formula, x represents a dot product, conj represents a conjugate, and sum represents a sum.
The method for determining the frame head position according to the calculation result of the delay correlation model comprises the following steps: and constructing a correlation curve graph, wherein the position of the peak value of the correlation value in the correlation curve graph is the frame head position.
The embodiment also provides a frame synchronization system under the large frequency offset, which is applied to the frame synchronization method under the large frequency offset, and comprises the following steps: the device comprises a signal acquisition module, a preprocessing module, a calculation module and a frame head determination module;
The signal acquisition module is used for generating a local pilot signal and receiving an external intermediate frequency signal;
The preprocessing module is used for preprocessing the received intermediate frequency signal and then intercepting and forming a section of complete burst signal containing pilot frequency symbol stream;
the calculation module calculates a conjugate multiplication model based on the local pilot signal and the complete burst signal, and then calculates a delay correlation model of the calculation result of the conjugate multiplication model;
And the frame head determining module determines the position of the frame head in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization.
Example 2
Signal bit data with the length of 5000 bits is randomly generated, pi/4-CQPSK modulation is adopted, BPSK modulation is adopted for pilot frequency, pilot frequency symbols are inserted into the front ends of the signal symbols to serve as frame heads, and the structure of the obtained burst signal is shown in figure 1.
After the modulated signal passes through the channel, the signal introduces noise, time offset and frequency offset, and the signal is subjected to frequency mixing, sampling rate conversion, low-pass filtering and matched filtering to obtain a symbol stream needing frame synchronization, wherein the matched filtering adopts a root raised cosine filter, and the roll-off factor takes a value between 0.2 and 0.5.
The frame synchronization algorithm provided by the invention is applied: pilot symbols of length 64 are acquired as a local pilot symbol stream for frame synchronization. The sliding window slides along the signal, 64 signal points are taken backwards from the current position, the 64 points in the sliding window and 64 local pilot symbols are subjected to conjugate multiplication in a one-to-one correspondence manner, the first 63 points and the last 63 points of the obtained product are subjected to conjugate multiplication in a one-to-one correspondence manner and summed, and a module value is obtained, so that the obtained result is the correlation value of the current position. The position of the peak of the correlation value is regarded as the frame head position.
In order to illustrate the performance of the frame synchronization algorithm provided by the present invention, the present embodiment uses a typical cross-correlation frame synchronization algorithm as a comparison algorithm.
In the case of the frequency offset of 0, fig. 2 and fig. 3 are correlation curves obtained by simulation when the signal-to-noise ratio is 0dB and 30dB, respectively, and it is seen that the influence of the signal-to-noise ratio on the frame synchronization algorithm is small, so that the signal-to-noise ratio is not required to be 30dB when the influence of the frequency offset on the frame synchronization algorithm is discussed.
Fig. 4, fig. 5 and fig. 6 are correlation curves obtained by simulation when normalized frequency offset is 0.001, 0.01 and 0.1 respectively, and under the condition of small frequency offset, the frame synchronization algorithm and the cross correlation algorithm provided by the invention have obvious correlation peaks, but the correlation curves obtained by the cross correlation frame synchronization algorithm in fig. 5 and fig. 6 have no obvious correlation peak, that is, the cross correlation frame synchronization algorithm is invalid under the condition of large frequency offset, and the frame synchronization algorithm provided by the invention can still be used under the condition of large frequency offset.
Fig. 2 to 6 are graphs obtained by performing 1 simulation, and for better convincing, the positions of the frame header obtained in 100 simulations in this embodiment are shown in table 1 and table 2, where table 1 and table 2 are the cases when normalized frequency offsets are 0.001 and 0.1, respectively. Since 4 times symbol rate sampling is used in the receive conversion process, both 133 and 134 are the correct frame header positions.
Table 1 frame header position at normalized frequency offset of 0.001
Table 2 frame header position at normalized frequency offset of 0.1
As can be seen from tables 1 and 2, when the normalized frequency offset is 0.001, the frame synchronization algorithm and the cross-correlation frame synchronization algorithm provided by the present invention can correctly detect the frame header position, and when the normalized frequency offset is 0.1, the cross-correlation frame synchronization algorithm fails, and only the frame synchronization algorithm provided by the present invention can correctly detect the frame header position.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the scope of the invention, but to limit the invention to the particular embodiments, and any modifications, equivalents, improvements, etc. that fall within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (6)
1. A method for frame synchronization in large frequency bias, comprising the steps of:
s1, generating a local pilot signal and receiving an external intermediate frequency signal;
S2, preprocessing the received intermediate frequency signal, and then intercepting to form a section of complete burst signal containing pilot frequency symbol stream;
the preprocessing process in step S2 includes: mixing, extracting and filtering the received intermediate frequency signals to form baseband IQ data, and intercepting the baseband IQ data to form a section of complete burst signal containing pilot frequency symbol stream;
S3, performing conjugate multiplication model calculation on the local pilot signal and the complete burst signal, and performing delay correlation model calculation on a conjugate multiplication model calculation result;
the method for calculating the conjugate multiplication model based on the local pilot signal and the complete burst signal comprises the following steps:
acquiring a pilot symbol with a length of N from a local pilot signal as a local pilot symbol stream for frame synchronization; sliding the sliding window along the complete burst signal, taking N signal points backwards from the current position, and carrying out conjugate multiplication on the N signal points in the sliding window and N local pilot symbols in a one-to-one correspondence manner;
s4, determining the frame head position in the complete burst signal according to the calculation result of the delay correlation model to perform frame synchronization;
the local pilot signal is expressed as: local= { l 1,l2,…,ln }; wherein the feature code l p＝eiπk, p=1, 2, …, n, k=0 or 1;
the external intermediate frequency signal is expressed as: rx= { r 1,r2,…,rm }, satisfying M > m·n+l, M representing the ratio of the sampling rate to the symbol rate, L being the sliding window length;
The complete burst signal is expressed as: { r k,rk+M.1,…,rk+M·(n-1) }, k=1, 2, …, L; step S3, performing conjugate multiplication operation on the complete burst signal and the local pilot signal to obtain:
2. the frame synchronization method of claim 1, wherein the filtering includes low-pass filtering and matched filtering, the matched filtering adopts a root raised cosine filter, and a roll-off factor takes a value between 0.2 and 0.5.
3. The frame synchronization method according to claim 1, wherein the baseband IQ data comprises a pilot portion and a data portion, the pilot portion being taken from a PN code or gold sequence.
4. The frame synchronization method under a large frequency offset according to claim 1, wherein the delay correlation model calculation process performed on the conjugate multiplication model calculation result is:
and (3) performing delay autocorrelation operation on the result of conjugate multiplication operation, wherein the calculation formula of the correlation value when the delay window length is 1 and the current position is k is expressed as follows:
In the above formula, x represents a dot product, conj represents a conjugate, and sum represents a sum.
5. The frame synchronization method under a large frequency offset as claimed in claim 4, wherein the method for determining the frame header position according to the calculation result of the delay correlation model comprises: and constructing a correlation curve graph, wherein the position of the peak value of the correlation value in the correlation curve graph is the frame head position.
6. A frame synchronization system under a large frequency offset, applied to the frame synchronization method under a large frequency offset of any one of claims 1 to 5, comprising: the device comprises a signal acquisition module, a preprocessing module, a calculation module and a frame head determination module;
The signal acquisition module is used for generating a local pilot signal and receiving an external intermediate frequency signal;
The preprocessing module is used for preprocessing the received intermediate frequency signal and then intercepting and forming a section of complete burst signal containing pilot frequency symbol stream;
the calculation module calculates a conjugate multiplication model based on the local pilot signal and the complete burst signal, and then calculates a delay correlation model of the calculation result of the conjugate multiplication model;
And the frame head determining module determines the position of the frame head in the complete burst signal according to the calculation result of the delay correlation model so as to perform frame synchronization.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110974427.1A CN113692045B (en) | 2021-08-24 | 2021-08-24 | Frame synchronization method and system under large frequency bias |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110974427.1A CN113692045B (en) | 2021-08-24 | 2021-08-24 | Frame synchronization method and system under large frequency bias |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113692045A CN113692045A (en) | 2021-11-23 |
| CN113692045B true CN113692045B (en) | 2024-05-14 |
Family
ID=78581839
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110974427.1A Active CN113692045B (en) | 2021-08-24 | 2021-08-24 | Frame synchronization method and system under large frequency bias |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113692045B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101110901A (en) * | 2007-07-31 | 2008-01-23 | 北京航空航天大学 | Synchronous generation method and device for carrier in ground digital television system |
| CN101547043A (en) * | 2009-04-21 | 2009-09-30 | 华为技术有限公司 | Method, device and terminal for realizing downlink synchornization |
| CN101924726A (en) * | 2009-06-17 | 2010-12-22 | 国民技术股份有限公司 | Frame synchronization method and device for OFDM system |
| CN110430156A (en) * | 2019-08-14 | 2019-11-08 | 北京智芯微电子科技有限公司 | The frame synchornization method and system of the OFDM data that happens suddenly transmission |
| CN111107033A (en) * | 2019-12-20 | 2020-05-05 | 重庆邮电大学 | Downlink frame timing synchronization method for 5G system |
| WO2021008070A1 (en) * | 2019-07-16 | 2021-01-21 | 京信通信***（中国）有限公司 | Large frequency deviation-prevention frame synchronization method, apparatus and system |
-
2021
- 2021-08-24 CN CN202110974427.1A patent/CN113692045B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101110901A (en) * | 2007-07-31 | 2008-01-23 | 北京航空航天大学 | Synchronous generation method and device for carrier in ground digital television system |
| CN101547043A (en) * | 2009-04-21 | 2009-09-30 | 华为技术有限公司 | Method, device and terminal for realizing downlink synchornization |
| CN101924726A (en) * | 2009-06-17 | 2010-12-22 | 国民技术股份有限公司 | Frame synchronization method and device for OFDM system |
| WO2021008070A1 (en) * | 2019-07-16 | 2021-01-21 | 京信通信***（中国）有限公司 | Large frequency deviation-prevention frame synchronization method, apparatus and system |
| CN110430156A (en) * | 2019-08-14 | 2019-11-08 | 北京智芯微电子科技有限公司 | The frame synchornization method and system of the OFDM data that happens suddenly transmission |
| CN111107033A (en) * | 2019-12-20 | 2020-05-05 | 重庆邮电大学 | Downlink frame timing synchronization method for 5G system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113692045A (en) | 2021-11-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103178947B (en) | The relevant carrier synchronization method with coding auxiliary based on time domain | |
| CN109981506A (en) | A kind of all-digital demodulation method based on open loop structure | |
| CN107342960B (en) | Non-data-aided frequency offset estimation method suitable for amplitude phase shift keying | |
| CN103532894B (en) | TCM-8PSK baseband signal demodulation method | |
| CN114205200B (en) | Method for achieving VDES system frame header capturing and carrier synchronization | |
| CN110099024B (en) | Method for transmitting frame synchronous code hidden in information code | |
| CN113114605B (en) | Signal processing method, device and system | |
| CN112399551B (en) | High-precision synchronization method for short-time burst signals | |
| CN113132285A (en) | Digital demodulation system and method | |
| CN110300079A (en) | A kind of msk signal coherent demodulation method and system | |
| CN105610755B (en) | Frequency offset estimation method and device for burst signal | |
| CN111371711B (en) | Fast acquisition and synchronization method of wireless burst communication system | |
| CN103368896A (en) | Carrier recovery method in high order modulation-demodulation | |
| CN107623647A (en) | A kind of carrier synchronization method based on scattered pilot auxiliary | |
| CN112600608B (en) | Multi-frame superimposed satellite signal capturing method and device | |
| CN113692045B (en) | Frame synchronization method and system under large frequency bias | |
| CN116488978B (en) | Frame synchronization method suitable for BR Bluetooth in test environment | |
| CN103200142A (en) | Two-state simplified method of non-recursive shaped offset quadrature phase shift keying (SOQPSK)-TG signal | |
| CN113115430A (en) | High-speed burst digital demodulation system | |
| CN110730149B (en) | Joint capturing method for translation special QPSK system | |
| CN108718461B (en) | Frequency offset resistant burst CPM signal frame synchronization method | |
| CN106341199A (en) | Signal to noise ratio determination method based on Manchester code | |
| CN114500206B (en) | Quick capturing and synchronizing method for GMSK burst communication system | |
| CN108055106B (en) | Recognition method for code word boundary based on RM code partial decoding auxiliary differential detection | |
| CN111212001B (en) | Joint channel estimation method for translation special QPSK system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |