The design of an improved matched filter in DSSS-GMSK system

8th International Conference on Advanced Infocomm Technology

Wei-Tong, Mao^1 ; Lin-Hua', Zheng^1 ; Liang-Jun, Xiang^1 ; Tan, Wang^1

College of Electronic Science and Engineering, National University of Defense Technology, Changsha

410073, China^1

关键词: DSSS signal;    GMSK modulation;    Low-SNR environment;    Matlab simulations;    MSK modulation;    Paper research;    Received signals;    Spread spectra;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/679/1/012024/pdf
DOI  :  10.1088/1742-6596/679/1/012024

来源: IOP

【 摘 要 】

This paper introduces the principle of DSSS-GMSK system, analyses the superiority of GMSK modulation over MSK modulation. Accord that the method of de-spread before demodulation can effectively improve the capability of the system with spread spectrum gain, this paper researches an improved method with matched filter to de-spread and demodulate the DSSS signals. The local PN code is modulated with GMSK modulation before being correlated with received signal, then we can get the synchronous PN code, de-spread and demodulate the signal. MATLAB simulation shows that this method is more efficient than the method of demodulation before despread in low SNR environment.