Title :
Adaptive Design of OFDM Radar Signal With Improved Wideband Ambiguity Function
Author :
Sen, Satyabrata ; Nehorai, Arye
Author_Institution :
Dept. of Electr. & Syst. Eng., Washington Univ. in St. Louis, St. Louis, MO, USA
Abstract :
We propose an adaptive technique to design the spectrum of an orthogonal frequency division multiplexing (OFDM) waveform to improve the radar´s wideband ambiguity function (WAF). The adaptive OFDM signal yields a better auto-correlation function (ACF) that results into an improved delay (range) resolution for the radar system. First, we develop a mutlicarrier OFDM signal model and the corresponding WAF at the output of the matched filter, emphasizing that the received signal depends on the scattering parameters of the target. Then, we devise an optimization procedure to select the OFDM waveform such that the volume of the corresponding WAF best approximates the volume of a desired ambiguity function. We demonstrate the improvement in the resulting ambiguity function, along with the associated ACF, through numerical examples. We find that the optimization algorithm puts more signal energy at subcarriers in which the target response is weaker.
Keywords :
OFDM modulation; matched filters; optimisation; radar signal processing; OFDM radar signal adaptive design; auto-correlation function; matched filter; mutlicarrier OFDM signal; optimization algorithm; orthogonal frequency division multiplexing waveform; wideband ambiguity function; Adaptive waveform design; OFDM radar; multifrequency scattering; wideband ambiguity function;
Journal_Title :
Signal Processing, IEEE Transactions on
DOI :
10.1109/TSP.2009.2032456