Feasibility Analysis of OFDM/OQAM Signals as Illuminator of Opportunity for Passive Detection

Passive detection system selecting illuminators of opportunity is one of the critical technologies in the field of radar. Orthogonal frequency division multiplex with Offset Quadrature Amplitude Modulation (OFDM/OQAM) is conceived as the illuminators of opportunity for passive radar system in this paper. The passive detection system based on OFDM/OQAM is established firstly, and then the detection feasibility and detection ability are analyzed by the average ambiguity function (AAF), range resolution, doppler resolution and maximum detection range. The numerical results demonstrate that the AAF of OFD-M/OQAM is perfect thumbtack shaped and the range resolution and doppler resolution of OFDM/OQAM signals can be reached to 16.91m and 0.139m/s, respectively. OFDM/OQAM with good detection performance and potential capability is suitable for illuminator of opportunity for passive detection system.

I. Introduction

Passive detection system is a receiver-only radar system that dissociates the receiving antenna from the transmitter, and it can detect and track targets of interest by utilizing noncooperative illuminators of opportunity (IOs), such as radio, television, and cellular signals [1]. In recent years, passive detection system is much better than a conventional radar system in different ways. Passive bistatic radar has strong anti-interference ability, high concealment, large coverage and other advantages [2]. In addition, passive detection radar can lead to spatial diversity and improve the detection capability of the target.