基于混沌的非连续频谱高速信道传输及性能研究

无线电频谱资源有限且日益紧缺，已成为高速数据传输的瓶颈。应用认知无线电技术，能智能识别、获取可用频带，从逻辑上产生足够宽的非连续频段实现高速数据传输。由于无线信道具有广播特性，认知网络仍易于遭受恶意窃取和攻击。混沌信号的物理特性使其能有效提高安全性能。然而，基于混沌及非连续频谱，实现高速、高安全性数据传输仍需解决如何使非连续频谱的传输波形呈混沌特性、高效传输参考混沌信号和可用频谱图样的问题。为此，我们将基于混沌，研究非连续频谱上的高速、高安全性信道传输新技术及理论性能，具体包括：（1）研究非连续频谱混沌多载波高速传输，并联合设计非相干高阶混沌调制方案；（2）研究非连续频谱图样检测方法及高码速LDPC混沌安全编码；（3）推导误比特率及保密容量等理论性能，并基于USRP构建原型系统加以验证。本课题的研究成果可用于非连续频谱上实现高速、高安全性混沌信息传输并可评估性能，从而为其应用提供理论基础。

The limited and scarce radio frequency resources have become the bottleneck for high data rate transmission. The cognitive radio technology can be applied to intelligently sense and identify the available spectrum bands, which can generate the non-contiguous spectrum bands logically wide enough to realize high data rate transmission. Due to broadcast property of the wireless channel, the cognitive radio network is still under the threat of eavesdropping and attack from the malicious users. The chaotic signal can effectively improve the security performance thanks to the physical property. However, in order to realize high data rate and high security information transmission based on chaos and non-contiguous spectrum bands, we still need to solve the problems that how to maintain the chaotic property of the transmission waveform over the non-contiguous spectrum bands and how to efficiently transmit the reference chaotic signal and perform the available spectrum bands detection. Hence, based on chaos, we will do research on the new channel transmission technology to realize high data rate as well as high security transmission over non-contiguous spectrum bands, and analyze the corresponding theoretical performance. Specifically, the proposed research plan includes: (1) we will do research on the high data rate chaotic multicarrier transmission over the non-contiguous spectrum bands, and then we will develop the joint design of non-contiguous subcarrier transmission and the non-coherent high order chaotic modulation; (2) we will do research on the non-contiguous spectrum band detection method and the high code rate secrecy coding schemes; (3) we will derive the theoretical performance including the bit error rate and secrecy capacity etc., then we will build up the prototype system based on universal software radio peripheral (USRP) to verify the system performance. The research results based on chaos achieved in this proposal can be used to utilize non-contiguous spectrum bands to realize the high data rate and high security information transmission, and also can be used for the system performance evaluation, thereby providing the theoretical basis for the application of high data rate transmission.