基于FFT的快速跳频同步信号存在性检测  

FFT-based Detection of Existence of Synchronization Signal for FFH System

作　　者：程郁凡[1] 韩玮[1] 李少谦[1] 

机构地区：[1]电子科技大学通信抗干扰技术国家级重点实验室,成都610054

出　　处：《电子科技大学学报》2003年第5期535-540,共6页Journal of University of Electronic Science and Technology of China

摘　　要：提出了在宽带快速跳频通信系统中的一种基于FFT的同步信号存在性检测算法,给出了干扰环境中在频域上计算信号归一化信噪比的限幅法、相邻跳做差法、二次限幅法、限幅做差再限幅法四种方法,分别进行了理论分析、计算机仿真和性能的比较。在白噪声环境和多音干扰环境下,四种方法计算出来的归一化信噪比与理论值差别不大,误差在±3 dB内;在部分频带噪声干扰环境下,二次限幅法与限幅做差再限幅法性能基本一致,明显优于限幅法和相邻两跳做差法,改善5 dB以上,其中二次限幅法实现简单并更为实用.A new FFT-based detection algorithm for the existence of synchronization signal in fast frequency-hopping (FFH) system is presented in this paper. Four methods (clipping, envelop-subtraction of two connective hops, iterative double-clipping, clipping-then-subtraction-then-clipping) of evaluating normalized signal to noise ratio(Eb/N0) in frequency domain with jamming are developed and compared. Analysis formulas of these methods are established as well. Our simulations show that numerical results of normalized signal to noise ratio are close to its theoretical analysis for both AWGN and multitone jamming environment, where discrepancy are within the range of ±3 dB. The overall performance of the latter two methods are 5 dB better than the first two methods for partial-band noise jamming. Iterative double-clipping is our recommended approach because of it's low complexity of implementation.

关 键 词：快速跳频 存在性检测 归一化信噪比 多音干扰 部分频带噪声干扰 二次限幅 

分 类 号：TN92[电子电信—通信与信息系统]