Examination of the ambiguity function of multiple successive OFDM transmitters for passive detection applications

摘要

Passive radars are systems that do not have a transmitter of their own but can detect and track targets using "transmitters of opportinuity" in the environment. Particularly in recent years, the work in this area has gained momentum as the number of transmitters used for wireless communications has increased and signal processing costs have dropped significantly. One of the most commonly used modulation types in these transmitters is Ortogonal Frequency Division Multiplexling. The suitability of a signal belonging to a transmitter for target detection and tracking is determined by examining the ambiguity function. In this report, we first examine the ambiguity function of a simulated single-channel OFDM signal source, then we examine the ambiguity function of multiple consecutive OFDM sources. Accordingly, the range resolutions for OFDM sources are determined as 141 m for a single-channel, 139.5 for two channels and 139 m for three consecutive channels.