计算机工程与应用
計算機工程與應用
계산궤공정여응용
COMPUTER ENGINEERING AND APPLICATIONS
2014年
5期
212-215
,共4页
全球定位系统(GPS)%弱信号%捕获%中频信号块累加%差分相干
全毬定位繫統(GPS)%弱信號%捕穫%中頻信號塊纍加%差分相榦
전구정위계통(GPS)%약신호%포획%중빈신호괴루가%차분상간
Global Positioning System(GPS)%weak signal%acquisition%block accumulation of intermediate frequency%difference correlation
提出一种基于FFT弱信号的中频信号块累加的差分相干累积算法。新算法利用中频信号块累加在中频信号FFT之前进行累加，减少相干运算量；利用差分相干累积在IFFT之后进行累积，消除平方损耗，解决了传统的基于FFT弱信号捕获时相干积分运算量过大和非相干累加算法引起的平方损耗问题。仿真实验表明该算法完成了对输入信噪比为-39 dB/2 MHz的信号的快速准确捕获，减少相干运算量，消除了平方损耗，提高了信噪比。
提齣一種基于FFT弱信號的中頻信號塊纍加的差分相榦纍積算法。新算法利用中頻信號塊纍加在中頻信號FFT之前進行纍加，減少相榦運算量；利用差分相榦纍積在IFFT之後進行纍積，消除平方損耗，解決瞭傳統的基于FFT弱信號捕穫時相榦積分運算量過大和非相榦纍加算法引起的平方損耗問題。倣真實驗錶明該算法完成瞭對輸入信譟比為-39 dB/2 MHz的信號的快速準確捕穫，減少相榦運算量，消除瞭平方損耗，提高瞭信譟比。
제출일충기우FFT약신호적중빈신호괴루가적차분상간루적산법。신산법이용중빈신호괴루가재중빈신호FFT지전진행루가，감소상간운산량；이용차분상간루적재IFFT지후진행루적，소제평방손모，해결료전통적기우FFT약신호포획시상간적분운산량과대화비상간루가산법인기적평방손모문제。방진실험표명해산법완성료대수입신조비위-39 dB/2 MHz적신호적쾌속준학포획，감소상간운산량，소제료평방손모，제고료신조비。
A differential coherent accumulated acquisition algorithm based on Fast Fourier Transform(FFT)weak signal block accumulation of the intermediate frequency is presented in this paper. To reduce coherence computation, the pro-posed algorithm performs the block accumulation of the intermediate frequency signal before FFT. To solve the two prob-lems in traditional acquisition algorithms based on FFT weak signal, namely great computation of coherent integral and square loss caused by incoherent accumulation, the proposed algorithm performs the differential coherent accumulation after IFFT. The simulation experimental results show that the algorithm quickly and accurately acquires the input signal with SNR of -39 dB/2 MHz. The algorithm reduces the calculations, eliminates square loss and improves the signal to noise ratio.
