Anti-Jamming Message-Driven Frequency Hopping—Part I: System Design
This is Part I of a two-part paper that considers anti-jamming system design in wireless networks based on message-driven frequency hopping (MDFH), a highly efficient spread spectrum technique. In this paper, we first analyze the performance of MDFH under hostile jamming. It is observed that while MDFH is robust under strong jamming, it experiences considerable performance losses under disguised jamming from sources that mimic the true signal. To overcome this limitation, we propose an anti-jamming MDFH (AJ-MDFH) system. The main idea is to transmit a secure ID sequence along with the information stream. The ID sequence is generated through a cryptographic algorithm using the shared secret between the transmitter and the receiver, it is then exploited by the receiver for effective signal extraction. It is shown that AJ-MDFH can effectively reduce the performance degradation caused by disguised jamming, and is also robust under strong jamming. In addition, we extend AJ-MDFH to the multi-carrier case, which can increase the system efficiency and jamming resistance significantly through jamming randomization and frequency diversity, and can readily be used as a collision-free multiple access system. Part II of the paper focuses on the capacity analysis of MDFH and AJ-MDFH under disguised jamming.