物理学报2011，Vol.60Issue(7)：75-82,8.
多径衰落信道下混沌直扩通信的可破解性
Breakability of chaotic direct sequence spreading spectrum secure system under multi-path fading channel
摘要
Abstract
Blind demodulation （breaking） of chaotic direct sequence spread spectrum （CD3S） signals is a challenging and leading issue under muhipath fading channel in the field of chaotic communication. Until now, there are neither equalization methods to remove the impact of the channel, nor the immediate breaking methods. Based on the existing study, the breakability of CD3S signals is analyzed under multipath fading channel by using unscented Kalman filter （UKF） chaotic fitting in this paper. Beginning with the state space equation for the CD3S signals in UKF chaotic fitting, the channel influence on the tracking error is analyzed in the process of UKF chaotic fitting, then the range of the message state estimation is derived, and finally a sufficient condition theorem is proposed for the CD3S signals to be broken. Simulation results show that CD3S signals can be broken successfully under the proposed condition with excellent performance of bit error rate （BER） , no matter whether the channel characteristic is either time-invariant or time-variant.关键词
混沌通信/破解/多径衰落信道/无先导卡尔曼滤波Key words
chaotic direct sequence spread spectrum secure communication/breaking/multi-path fading channel/unscented Kalman filter分类
信息技术与安全科学引用本文复制引用
白鹭,郭静波..多径衰落信道下混沌直扩通信的可破解性[J].物理学报,2011,60(7):75-82,8.基金项目
国家重点实验室项目（批准号：SKLD09M25）资助的课题. （）
