CN102288975B - Capturing method based on DFT (Discrete Fourier Transformation) optimization - Google Patents
Capturing method based on DFT (Discrete Fourier Transformation) optimization Download PDFInfo
- Publication number
- CN102288975B CN102288975B CN2011101209097A CN201110120909A CN102288975B CN 102288975 B CN102288975 B CN 102288975B CN 2011101209097 A CN2011101209097 A CN 2011101209097A CN 201110120909 A CN201110120909 A CN 201110120909A CN 102288975 B CN102288975 B CN 102288975B
- Authority
- CN
- China
- Prior art keywords
- dft
- points
- value
- calculation
- optimization
- 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.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 38
- 238000005457 optimization Methods 0.000 title claims abstract description 14
- 230000009466 transformation Effects 0.000 title description 3
- 238000003775 Density Functional Theory Methods 0.000 claims abstract description 78
- 238000005070 sampling Methods 0.000 claims description 6
- 238000004364 calculation method Methods 0.000 abstract description 17
- 238000013139 quantization Methods 0.000 abstract description 7
- 238000004891 communication Methods 0.000 abstract description 3
- 238000001228 spectrum Methods 0.000 description 5
- 238000011160 research Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000010845 search algorithm Methods 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Images
Landscapes
- Position Fixing By Use Of Radio Waves (AREA)
Abstract
本发明属于通信和导航领域,公开了一种基于DFT优化的捕获方法。针对现有的卫星导航捕获方法中的效率、资源和功耗较大的问题,本发明通过对DFT的系数进行量化实现了对DFT的计算进行优化,同时根据需要对DFT点数进行优化,节约了大量的计算量、存储和其它等资源。在导航应用中,除了对DFT系数进行低比特量化,同时也根据搜索多普勒偏移范围对DFT点数进行裁剪,从而使得DFT的计算量和计算点数都大量减少,节约存储资源、计算资源、时间和功耗等。本发明的方法可以有效应用于卫星导航。
The invention belongs to the field of communication and navigation, and discloses a capture method based on DFT optimization. Aiming at the problems of large efficiency, resources and power consumption in the existing satellite navigation capture method, the present invention realizes the optimization of DFT calculation by quantizing the coefficients of DFT, and at the same time optimizes the number of DFT points according to needs, saving A large amount of computing, storage and other resources. In navigation applications, in addition to low-bit quantization of DFT coefficients, the number of DFT points is also cut according to the search Doppler offset range, so that the calculation amount and calculation points of DFT are greatly reduced, saving storage resources, computing resources, time and power consumption etc. The method of the invention can be effectively applied to satellite navigation.
Description
技术领域 technical field
本发明属于通信和导航领域,尤其涉及用于卫星导航的捕获方法。The invention belongs to the field of communication and navigation, in particular to a capturing method for satellite navigation.
背景技术 Background technique
全球定位系统(GPS,Global Position System)是新一代的精密卫星定位系统。GPS接收机对所接收信号的处理通常包括信号的捕获、信号载波和码锁定、导航电文和伪距的提取与计算以及定位值的解算。GPS系统采用的是扩频通信技术,在扩频接收机解扩解调前必须使接收机本地恢复的扩频码与载波与接收信号同步,只有在码相位与载波频率误差在一定范围内时,解调器才能正常工作。由于存在频率源的漂移、电波传输的时延、多普勒频移、多径效应等因素的影响,码相位以及载波的同步会具有一定的不确定性,因此接收机必须首先对信号进行捕获,将码相位与载波频率估计误差降低到一定范围内才能提供给跟踪环路,进行信号跟踪。导航卫星信号的捕获是GPS接收机信号处理的第一步和关键。Global Positioning System (GPS, Global Position System) is a new generation of precise satellite positioning system. The processing of the received signal by the GPS receiver usually includes signal acquisition, signal carrier and code locking, extraction and calculation of navigation message and pseudo-range, and solution of positioning value. The GPS system uses spread spectrum communication technology. Before the spread spectrum receiver despreads and demodulates, the spread spectrum code recovered locally by the receiver must be synchronized with the carrier and the received signal. Only when the error between the code phase and the carrier frequency is within a certain range , the demodulator can work normally. Due to the influence of frequency source drift, radio wave transmission delay, Doppler frequency shift, multipath effect and other factors, the synchronization of code phase and carrier will have certain uncertainty, so the receiver must first capture the signal , the code phase and carrier frequency estimation error can be reduced to a certain range before it can be provided to the tracking loop for signal tracking. The capture of navigation satellite signals is the first step and the key to GPS receiver signal processing.
目前接收机中,特别在军码接收机和多模接收机中,资源、体积和功耗是约束接收机发展的一大难题。针对这一问题,国内外许多机构和单位进行了大量研究。卫星信号的捕获大多数是基于时域上与频域上实现,传统的方法是在时域上利用串行搜索的办法对扩频码进行捕获。在文献“Van Nee,Coenen,Davenport.New Fast GPS Code-Acquisition TechniqueUsing FFT,Electronic Letters,1991,vol.27,NO.2:158-160”首先提出使用FFT实现扩频码的快速捕获方法;在文献“C.Yang.Fast code acquisition with FFT and its sampling schemes,Proc.Institute of Navigation ION-GPS 96,Kansas City,MO,September 1996,1729-173”对FFT的多种抽样方案进行了比较和分析;在文献“Extended Replica Folding for DirectAcquisition of GPS P-Code and Its Performance Analysis,Proceedings of ION GPS 2000.SaltLake City,Ut:The Institute of Navigation,2000.2070-2078”提出了XFAST实现P(Y)码的快速捕获方案,又在文献“Sequential Block Search for Direct Acquisition of Long Codes underLarge Uncertainty,Proceedings of the 2001 National Technical Meeting.Long Beach,CA:ION,Jan.2001.408-414”提出了序列块搜索算法,并对利用FFT实现短周期码,长周期码以及无周期码的捕获方法进行分类和归纳。国内对长码直捕的方法的分析也很多,并且很多在实现上给出了相应的研究成果,如大规模并行相关器实现的串并结合的滑动相关器法,扩展复制重叠均值法,以及PMF-FFT的方法等。In current receivers, especially in military code receivers and multi-mode receivers, resources, volume and power consumption are major problems that restrict the development of receivers. Aiming at this problem, many institutions and units at home and abroad have conducted a lot of research. The acquisition of satellite signals is mostly based on the time domain and frequency domain. The traditional method is to use the serial search method to capture the spread spectrum code in the time domain. In the literature "Van Nee, Coenen, Davenport. New Fast GPS Code-Acquisition Technique Using FFT, Electronic Letters, 1991, vol.27, NO.2: 158-160" first proposed a fast acquisition method using FFT to realize the spreading code; The literature "C. Yang. Fast code acquisition with FFT and its sampling schemes, Proc. Institute of Navigation ION-GPS 96, Kansas City, MO, September 1996, 1729-173" compared and analyzed various sampling schemes of FFT ; In the document "Extended Replica Folding for DirectAcquisition of GPS P-Code and Its Performance Analysis, Proceedings of ION GPS 2000.SaltLake City, Ut: The Institute of Navigation, 2000.2070-2078" proposed XFAST to realize the fast P(Y) code The capture scheme, and in the literature "Sequential Block Search for Direct Acquisition of Long Codes under Large Uncertainty, Proceedings of the 2001 National Technical Meeting. Long Beach, CA: ION, Jan. 2001.408-414" proposed a sequence block search algorithm, and used FFT implements short-period codes, long-period codes and acquisition methods of no-period codes for classification and induction. There are also many domestic analysis methods for long-code direct capture, and many corresponding research results have been given in terms of implementation, such as the sliding correlator method of serial-parallel combination realized by large-scale parallel correlators, the extended copy overlapping mean method, and The method of PMF-FFT, etc.
由于卫星和接收机之间存在的相对运动,在接收机使用过程中必然会引入多普勒频移。而多普勒频移将导致扩频增益发生衰减,影响捕获工作,因此在捕获过程中必须进行相应的补偿处理,去除多普勒频移所产生的影响。为了实现低功耗、低资源和小型化的接收机,特别在未来的多模接收机中,许多学者提出了众多的优化方法,但是效率、资源、功耗等的优化问题依然是捕获的研究重点。Due to the relative motion between the satellite and the receiver, the Doppler frequency shift will inevitably be introduced during the use of the receiver. The Doppler frequency shift will lead to the attenuation of the spread spectrum gain and affect the capture work. Therefore, corresponding compensation must be carried out during the capture process to remove the impact of the Doppler frequency shift. In order to achieve low power consumption, low resource and miniaturized receivers, especially in future multi-mode receivers, many scholars have proposed numerous optimization methods, but the optimization problems of efficiency, resources, power consumption, etc. are still the research of capture focus.
发明内容 Contents of the invention
本发明是为了解决现有的卫星导航捕获方法中的效率、资源和功耗较大的问题,提出了一种基于DFT优化的捕获方法。The invention aims to solve the problems of large efficiency, resources and power consumption in the existing satellite navigation capture method, and proposes a capture method based on DFT optimization.
本发明的技术方案是:一种基于DFT优化的捕获方法,包括如下步骤:Technical scheme of the present invention is: a kind of capture method based on DFT optimization, comprises the steps:
S1,把接收到的卫星信号N点数据和本地的伪随机码的N点数据进行相关运算;S1, correlating the N-point data of the received satellite signal with the N-point data of the local pseudo-random code;
S2,对步骤S1中每次相关运算的结果作N点DFT,其中x(n)为相关运算的结果,X(k)为计算DFT后的频域结果,具体过程如下:把频域复平面上N个等分点缩小为M等分,设N=M*m,M等分后,把M等分上的值代替原来N等分值即N等分值在区间
S3,将DFT频域结果和预设的门限值比较,如果超过门限值,得到信号的多普勒频移值,如果没有超过门限值,则码相位移动一个数据,继续步骤S1,如果所有的相位搜索完毕后仍然没有结果,则更换中频或码序列,继续搜索。S3, comparing the DFT frequency domain result with the preset threshold value, if the threshold value is exceeded, the Doppler frequency shift value of the signal is obtained, if the threshold value is not exceeded, the code phase is shifted by one data, and the step S1 is continued. If there is still no result after all phase searches are completed, replace the IF or code sequence and continue searching.
进一步的,所述步骤S2和步骤S3之间还包括如下步骤:Further, the following steps are also included between the step S2 and the step S3:
计算DFT计算点数的最大值其中,fs为接收到的卫星信号的采样率,Δf为多普列频率偏移最大值,然后根据计算得到的点数nmax计算DFT,即计算k的区间为[N-nmax/2N-1]和[0 nmax/2-1]的X(k)的值。Calculate the maximum value of DFT calculation points Among them, f s is the sampling rate of the received satellite signal, Δf is the maximum value of the Doppler frequency offset, and then calculate the DFT according to the calculated number of points n max , that is, the interval for calculating k is [Nn max /2N-1] and the value of X(k) of [0 n max /2-1].
本发明的有益效果:本发明通过提供一种基于DFT的算法而提出的一种高效和低资源优化算法,并有效应用于卫星导航。通过对DFT的系数进行量化,进而对DFT的计算进行优化,同时根据需要对DFT点数进行优化,节约了大量的存储资源和计算量。在导航应用中,除了对DFT系数进行低比特量化,同时也根据搜索多普勒偏移范围对DFT点数进行裁剪,从而使得DFT的计算量和计算点数都大量减少,节约存储资源、计算资源、时间和功耗等。Beneficial effects of the present invention: the present invention proposes a high-efficiency and low-resource optimization algorithm by providing a DFT-based algorithm, and is effectively applied to satellite navigation. By quantizing the coefficients of the DFT, the calculation of the DFT is optimized, and the number of DFT points is optimized according to the needs, which saves a lot of storage resources and calculations. In navigation applications, in addition to low-bit quantization of DFT coefficients, the number of DFT points is also cut according to the search Doppler offset range, so that the calculation amount and calculation points of DFT are greatly reduced, saving storage resources, computing resources, time and power consumption etc.
附图说明 Description of drawings
图1是本发明的基于DFT优化的捕获方法流程示意图。Fig. 1 is a schematic flow chart of the capture method based on DFT optimization of the present invention.
图2是本发明实施例的比特量化的DFT系数示意图。Fig. 2 is a schematic diagram of bit-quantized DFT coefficients according to an embodiment of the present invention.
具体实施方式 Detailed ways
下面结合附图和具体的实施例对本发明作进一步的阐述。The present invention will be further elaborated below in conjunction with the accompanying drawings and specific embodiments.
传统的计算DFT的方法是根据公式进行计算,即每个频域分量都得计算N个输入信号与频域复平面上N个等分点的乘积。因此在接收机捕获过程中,基于传统的DFT的捕获方法,会带来效率、资源和功耗较大的问题。The traditional method of calculating DFT is based on the formula Perform calculations, that is, each frequency domain component has to calculate the product of N input signals and N equal division points on the frequency domain complex plane. Therefore, in the acquisition process of the receiver, the acquisition method based on the traditional DFT will bring problems of efficiency, resource and power consumption.
本发明的基于DFT优化的捕获方法,具体流程如图1所示,包括如下步骤:The capture method based on DFT optimization of the present invention, concrete process as shown in Figure 1, comprises the following steps:
S1,把接收到的卫星信号N点数据和本地的伪随机码的N点数据进行相关运算;S1, correlating the N-point data of the received satellite signal with the N-point data of the local pseudo-random code;
S2,对步骤S1中每次相关运算的结果作N点DFT,其中x(n)为相关运算的结果,X(k)为计算DFT后的频域结果,具体过程如下:把频域复平面上N个等分点缩小为M等分,设N=M*m,M等分后,把M等分上的值代替原来N等分值即N等分值在区间
S3,将DFT频域结果和预设的门限值比较,如果超过门限值,得到信号的多普勒频移值,如果没有超过门限值,则码相位移动一个数据,继续步骤S1,如果所有的相位搜索完毕后仍然没有结果,则更换中频或码序列,继续搜索。S3, comparing the DFT frequency domain result with the preset threshold value, if the threshold value is exceeded, the Doppler frequency shift value of the signal is obtained, if the threshold value is not exceeded, the code phase is shifted by one data, and the step S1 is continued. If there is still no result after all phase searches are completed, replace the IF or code sequence and continue searching.
为了进一步的减少计算量,在步骤S2和步骤S3之间还包括如下步骤:计算DFT计算点数的最大值其中,fs为接收到的卫星信号的采样率,Δf为多普列频率偏移最大值,然后根据计算得到的点数nmax计算DFT,即计算k的区间为[N-nmax/2 N-1]和[0 nmax/2-1]的X(k)的值。在这里,DFT变换频域表示范围为0到fs,搜索多普列频移范围为-1*Δf~Δf。In order to further reduce the calculation amount, the following steps are also included between step S2 and step S3: calculating the maximum value of DFT calculation points Among them, f s is the sampling rate of the received satellite signal, Δf is the maximum value of the Doppler frequency offset, and then calculate the DFT according to the calculated number of points n max , that is, the interval for calculating k is [Nn max /2 N-1 ] and the value of X(k) of [0 n max /2-1]. Here, the DFT transform frequency domain representation ranges from 0 to f s , and the search Doppler frequency shift ranges from -1*Δf to Δf.
设相关运算的结果为x(n),根据DFT变换,则序列x(n)的DFT为:Assuming that the result of the correlation operation is x(n), according to the DFT transformation, the DFT of the sequence x(n) is:
由于ejθ=cosθ-jsinθ,所以DFT系数是单位圆上的N等分点上的数据。如果把圆分成M<N,通常N为M的整数倍,那么DFT的系数只有M个,但是输入数据点数不变,通过把原来圆N等分的数据在M等分附近的数据划入M等分的数据之中。选择合适的M,可以极大节约DFT的存储资源、计算量和计算资源。Since e jθ =cosθ-jsinθ, the DFT coefficient is the data on the N equally divided points on the unit circle. If the circle is divided into M<N, usually N is an integer multiple of M, then there are only M coefficients of DFT, but the number of input data points remains unchanged, by dividing the data of the original circle N equal parts into M among the equally divided data. Choosing an appropriate M can greatly save the storage resources, calculation amount and computing resources of DFT.
当M取8进行等分时,可以以获得一个较优的效果。下面以M=8为例进行说明。When M is equal to 8, a better effect can be obtained. The following uses M=8 as an example for illustration.
本发明按M取8等分时进行计算,根据DFT的可知量化后所有的系数都位于复平面的单位圆上。如图2所示,把一个复平面圆周分成了8等份,对DFT系数进行2比特量化即可把八等分上的点全部表示完毕,并对系数进行适当的放大以后的量化系数为[1.5,1+i,1.5i,-1+i,-1.5,-1-i,-1.5i,1-i]。根据DFT的量化系数,DFT运算乘法资源可以由原来的乘法器变成了直连信号(系数为±1)或者几个寄存器和加法器(系数为±1.5),这将大大缩减了DFT的运算量。假设现在要做256点DFT,因为M取8进行等分,所以原来256等分中的240~256和1~16等分点用M=8等分点中的第一个等分点对应的DFT系数为(1.5,0)代替,17~48等分点用八等分点的第二个等分点的DFT系数变为(1,i)代替,49~80等分点用八等分点的第三个等分点DFT系数变为(15i)代替,剩余的系数及其它点数的DFT以此类推。The present invention calculates when taking 8 equal divisions by M, according to the DFT It can be seen that all the coefficients after quantization are located on the unit circle of the complex plane. As shown in Figure 2, a complex plane circle is divided into 8 equal parts, and the 2-bit quantization of the DFT coefficients can express all the points on the eight equal parts, and the quantized coefficients after proper amplification of the coefficients are [ 1.5,1+i,1.5i,-1+i,-1.5,-1-i,-1.5i,1-i]. According to the quantization coefficient of DFT, the multiplication resource of DFT operation can be changed from the original multiplier to a direct signal (with a coefficient of ±1) or several registers and adders (with a coefficient of ±1.5), which will greatly reduce the operation of DFT quantity. Suppose now to do 256-point DFT, because M takes 8 for equal division, so the 240-256 and 1-16 equal-division points in the original 256 equal-division points correspond to the first equal-division point among M=8 equal-division points The DFT coefficient is replaced by (1.5,0), and the DFT coefficient of the second equal point of the 17th to 48th equal point is replaced by (1,i), and the 49th to 80th equal point is replaced by the eighth equal point The DFT coefficient of the third bisection point of the point becomes (15i) instead, and the DFT of the remaining coefficients and other points can be deduced by analogy.
为了只对多普勒的频带进行搜索,可以调整DFT系数,把系数集中于需要的频带范围内进行变换,而对其它频带的参数则不进行计算,这样还可以节省大量的计算量。如果采样率为fs,那么DFT变换频域表示范围为0到fs。如果搜索多普列范围为±10KHZ,那么计算范围只要就可以计算出最大的计算点数为nmax,然后根据这个点数就可以计算需要的DFT。假设采用4ms数据做256点DFT,因此频谱分辨率为对应在计算离散DFT时候,为了搜索±10KHz信号,需要计算的点数为因此只需要216点到255点、0点到39点的X(k)即可。因而不需要计算全部的256点DFT。同样如果只搜索±5KHz,只需要计算236到255点、0点到19点的DFT即可,其它频率计算原理一样。如果需要全频域搜索,或者搜索范围很大,导致计算步骤数超过FFT的方式的话,可以把这种量化方式应用到FFT上去。In order to search only the Doppler frequency band, the DFT coefficients can be adjusted, and the coefficients are concentrated in the required frequency band range for transformation, while the parameters of other frequency bands are not calculated, which can also save a lot of calculation. If the sampling rate is f s , then the DFT transform frequency domain representation ranges from 0 to f s . If the range of the search Doppler column is ±10KHZ, then the calculation range is as long as The maximum number of calculation points can be calculated as n max , and then the required DFT can be calculated according to this number of points. Assume that 4ms data is used to do 256-point DFT, so the spectral resolution is corresponding to When calculating the discrete DFT, in order to search for ±10KHz signals, the number of points to be calculated is Therefore, only X(k) from 216 to 255 and from 0 to 39 is needed. Thus there is no need to compute the full 256-point DFT. Similarly, if you only search for ±5KHz, you only need to calculate the DFT from 236 to 255 points, and from 0 to 19 points, and the calculation principles for other frequencies are the same. If you need to search in the full frequency domain, or the search range is so large that the number of calculation steps exceeds the FFT method, you can apply this quantization method to the FFT.
可以看出,本发明的通过对DFT的系数进行量化,可以简化DFT的计算,同时量化以后的根据需要对DFT的点数进行优化,可以节约大量的存储资源和计算量。在导航应用中,除了对DFT系数进行量化,同时也根据搜索多普勒偏移范围对DFT点数进行裁剪,使得DFT的计算点数和计算量都减少,节约存储资源、计算资源、时间和功耗等,本方法可以有效应用于卫星导航。It can be seen that the present invention can simplify DFT calculation by quantizing DFT coefficients, and at the same time optimize the number of DFT points after quantization according to needs, which can save a lot of storage resources and calculation amount. In navigation applications, in addition to quantizing DFT coefficients, the number of DFT points is also tailored according to the search Doppler offset range, which reduces the number of DFT calculation points and the amount of calculation, saving storage resources, computing resources, time and power consumption etc., this method can be effectively applied to satellite navigation.
本领域的普通技术人员将会意识到,这里所述的实施例是为了帮助读者理解本发明的原理,应被理解为本发明的保护范围并不局限于这样的特别陈述和实施例。本领域的普通技术人员可以根据本发明公开的这些技术启示做出各种不脱离本发明实质的其它各种具体变形和组合,这些变形和组合仍然在本发明的保护范围内。Those skilled in the art will appreciate that the embodiments described here are to help readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical revelations disclosed in the present invention without departing from the essence of the present invention, and these modifications and combinations are still within the protection scope of the present invention.
Claims (4)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2011101209097A CN102288975B (en) | 2011-05-11 | 2011-05-11 | Capturing method based on DFT (Discrete Fourier Transformation) optimization |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN2011101209097A CN102288975B (en) | 2011-05-11 | 2011-05-11 | Capturing method based on DFT (Discrete Fourier Transformation) optimization |
Publications (2)
Publication Number | Publication Date |
---|---|
CN102288975A CN102288975A (en) | 2011-12-21 |
CN102288975B true CN102288975B (en) | 2012-11-07 |
Family
ID=45335538
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN2011101209097A Expired - Fee Related CN102288975B (en) | 2011-05-11 | 2011-05-11 | Capturing method based on DFT (Discrete Fourier Transformation) optimization |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN102288975B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN106980125B (en) * | 2016-01-18 | 2022-02-01 | 北京信息科技大学 | Reduced calculation amount deblurring processing method for XFAST capture in satellite navigation |
CN107728104A (en) * | 2017-10-09 | 2018-02-23 | 中国电子科技集团公司第二十研究所 | A kind of improved satellite navigation interference direction-finding method |
CN108318900B (en) * | 2017-12-29 | 2021-04-23 | 中国科学院光电研究院 | A High-Precision Frequency Acquisition Method of Periodic Pulse Enhanced Navigation Signal |
CN112214895A (en) * | 2020-10-14 | 2021-01-12 | 中国船舶重工集团公司第七二四研究所 | Fourier multi-beam forming method with transform point number optimization design |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6452961B1 (en) * | 2000-09-12 | 2002-09-17 | Interstate Electronics Corporation | Massively paralleled sequential test algorithm |
CN101132191A (en) * | 2007-10-15 | 2008-02-27 | 北京航空航天大学 | A kind of GNSS receiver baseband signal processing method |
CN101561484A (en) * | 2009-05-11 | 2009-10-21 | 北京航空航天大学 | Method for acquiring pseudo code of GNSS signal |
EP2223143A2 (en) * | 2007-05-10 | 2010-09-01 | Qualcomm Incorporated | Gnss signal processor |
-
2011
- 2011-05-11 CN CN2011101209097A patent/CN102288975B/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6452961B1 (en) * | 2000-09-12 | 2002-09-17 | Interstate Electronics Corporation | Massively paralleled sequential test algorithm |
EP2223143A2 (en) * | 2007-05-10 | 2010-09-01 | Qualcomm Incorporated | Gnss signal processor |
CN101132191A (en) * | 2007-10-15 | 2008-02-27 | 北京航空航天大学 | A kind of GNSS receiver baseband signal processing method |
CN101561484A (en) * | 2009-05-11 | 2009-10-21 | 北京航空航天大学 | Method for acquiring pseudo code of GNSS signal |
Non-Patent Citations (2)
Title |
---|
包亮等.基于DFT快速算法对扩频码捕获过程的优化.《航天控制》.2010,第28卷(第3期),全文. |
基于DFT快速算法对扩频码捕获过程的优化;包亮等;《航天控制》;20100630;第28卷(第3期);全文 * |
Also Published As
Publication number | Publication date |
---|---|
CN102288975A (en) | 2011-12-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103645483B (en) | Beidou signal capturing method in weak signal environment | |
CN101246210B (en) | GPS locating method | |
CN101561484B (en) | Method for acquiring pseudo code of GNSS signal | |
US20230111314A1 (en) | A GNSS signal acquisition method based on FPGA step-by-step code phase refinement | |
Li et al. | GPS signal acquisition via compressive multichannel sampling | |
CN102288975B (en) | Capturing method based on DFT (Discrete Fourier Transformation) optimization | |
CN105553506B (en) | A kind of quick capturing method and device of long code spread-spectrum signal | |
TW200539588A (en) | Apparatus and method for acquiring spread-spectrum signals | |
CN104898136A (en) | Capturing method of Beidou second-generation B1 signals and system thereof | |
CN100553169C (en) | Short-period spreading code time frequency parallel searching method based on frequency folding | |
CN103926604B (en) | Based on the weak signal catching method of overlapping difference circulation coherent integration | |
Tamazin et al. | Robust fine acquisition algorithm for GPS receiver with limited resources | |
CN110456393A (en) | Beidou weak signal quick capturing method | |
CN101320084A (en) | Real-time Processing Method of Satellite Positioning Signal | |
CN102798871B (en) | Pseudo code capturing method and device based on pseudo code reconstruction | |
Sagiraju et al. | Fast acquisition implementation for high sensitivity global positioning systems receivers based on joint and reduced space search | |
Leclere et al. | Modified parallel code-phase search for acquisition in presence of sign transition | |
CN102841361A (en) | Fast capturing method for ordinary ranging codes of signals of global navigation satellite system | |
CN105301610B (en) | A kind of Novel GPS L5 signal quick catching methods of anti-symbol saltus step | |
CN101762803B (en) | Differential correlator applied to global navigation satellite system receiver | |
CN103616703B (en) | A kind of base band data disposal route of navigation neceiver and system | |
CN104639206B (en) | Synchronization device and synchronization method thereof | |
CN105227210B (en) | CPM signal synchronizing methods under a kind of exceedingly odious channel circumstance | |
CN105866803A (en) | Baseband signal quick capturing algorithm for Beidou second-generation satellite navigation receiver based on FPGA | |
Lin et al. | Acquisition of GPS software receiver using split-radix FFT |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121107 Termination date: 20150511 |
|
EXPY | Termination of patent right or utility model |