Direct Sequence Spread Spectrum Parallel Acquisition in a Time Selective Frequency Nonselective Rayleigh Fading Channel

• Main Authors: Shu, De Lan, 許迪嵐
• Other Authors: Kou, Foon Yeon
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/42265979578245152839

碩士 === 中原大學 === 電機工程研究所 === 81 === In modern communication, spread-specrum systems that offer high immunity to interference become more important. However, this high immunity can be fully exploited only if precise receiver synchronization is performed. In this thesis, a parallel acquisition scheme utilizing a bank of N parallel I-Q noncoherent matched filters for direct-sequence spread-spectrum( DS/SS) is discussed [1] [2]. The mean acquisition time performance is analyzed by Markov process of detection, false alarm and missing probabilities. Channel is modeled as a Time Selective and Frequency Nonselective Rayleigh Fading multiple paths. We also consider the performance for various SNRs(signal to noise ratio) and with multiple received paths. In this study, various parameters such as different SNRs , matched filter lengths, successive constant fading process lengths, and correlation coefficients are examined to obtain the appropriate mean acquisition time for the two paths (including the second nonsynchronous path) receiving systems. The results and application modes of multiple receiving paths should facilitate the fast parallel synchronization in further DS/SS mobile communication.