OFDM Chirp Waveform Design Based on Subchirp Bandwidth Overlap and Segmented Transmitting for Low Correlation...

There are some special merits for the orthogonal frequency division multiplexing (OFDM)chirp waveform as multiple input multiple output (MIMO) signals. This signal has high rangeresolution, good Doppler tolerance, and constant modulus superiority since it exploits a fullbandwidth and is based on chirp signals. The correlation sidelobe peaks level are critical for thedetection requirement of MIMO radar signals, however conventional OFDM chirp signals producehigh autocorrelation sidelobe peaks (ASP) and cross-correlation peaks (CP), which reducesdetection performance. In this paper, we explore the structure of OFDM chirp signals'autocorrelation function and proposed a scheme to reduce the designed signal's ASP by a designingsuitable range of subchirp bandwidth and a segmented transmit-receive mode. Next, we explore asuitable range of interval between the chirp rates of each two signals to reduce the CP. Thesimulation of designed signals verifies the effectiveness of the proposed methods in the reductionof ASP and CP, with the correlation performance being compared with recent relate studies. Inaddition, the multiple signals detection and one-dimensional range image simulation show thegood detection performance of a designed signal in MIMO radar detection.