CAJ | 학술논문

提出了一种扩频方案.通过格雷互补序列树型扩展算法构造对偶多值PN码混合矩阵,并利用该混合矩阵对信息序列进行M元扩频,这种扩频方式能有效地提高频带效率和抗截获性能,比直接序列扩频具有3dB的性能改善.针对伪码较长的扩频通信系统码同步计算复杂度高、硬件实现困难的缺点,提出了一种基于两级FFT的快速捕获算法,其计算复杂度与传统的PMF-FFT算法相比能下降一个数量级.通过同相、正交支路进行交叉混合数据解扩,能有效消除载波相位偏移对系统性能的影响.
제출료일충확빈방안.통과격뢰호보서렬수형확전산법구조대우다치PN마혼합구진,병이용해혼합구진대신식서렬진행M원확빈,저충확빈방식능유효지제고빈대효솔화항절획성능,비직접서렬확빈구유3dB적성능개선.침대위마교장적확빈통신계통마동보계산복잡도고、경건실현곤난적결점,제출료일충기우량급FFT적쾌속포획산법,기계산복잡도여전통적PMF-FFT산법상비능하강일개수량급.통과동상、정교지로진행교차혼합수거해확,능유효소제재파상위편이대계통성능적영향.
We propose a novel class of M-ary spread spectrum based on the quasi-Orthogonal multi-PN code. A hybrid matrix based on the Golay complementary sequence is deduced and used for the M-ary spread spectrum, which greatly enhances the band efficiency and robustness, and compared with the spread spectrum technique, it provides a larger spread gain and a stonger anti-intercept capture capability. In order to overcome the difficulties incurred by a long PN code spread spectrum system such as high computational complexity of synchronization and complicated hardware realization, a novel fast acquisition algorithm based on the 2-stage FFT is presented whose complexity is largely reduced compared with the conventional PMF-FFT algorithm. The receiver can effectively eliminate distortion caused by phase offset of the carrier using quadrature subchannel information for intersect data dispreading.