Waveform Design For Range Sidelobe Suppression

Radar detection ability for small target is being challenged by the various and complex environments. Small targets are easily to be covered because of the radar range sidelobes. It greatly influences the performance of radar target detection. The suppression of range sidelobes by using waveform design provides an important benefit in theory and application for small target detection. In this thesis, the waveform design methods are used to research the problem of range sidelobe suppression. The main contributions of this thesis are as follows:1. Under the background of white Gaussian noise, a pulse compression algorithm is proposed based on the orthogonal frequency-division multiplexing(OFDM) waveform with cyclic prefix, and the range sidelobes of OFDM radar are eliminated. In order to solve the problems of pulse length and transmitted energy redundancy, the OFDM waveform design algorithm is proposed for the situation of single antenna, the pulse compression is achieved with zero sidelobes by using arbitrary length OFDM pulse, and the problem of transmitted energy redundancy is also solved.2. Under the background of white Gaussian noise, for the influence of cross-correlation of different transmitted signals and range sidelobes for the statistical multiple-input multiple-output(MIMO) radar which shares the same frequency band, the frequency shared MIMO OFDM radar is proposed based on OFDM waveform with cyclic prefix. The joint pulse compression and pulse coherent integration algorithm of frequency shared MIMO OFDM radar is proposed, the interference of different transmitted signals and range sidelobes are eliminated.3. For the problems of transmitted pulse length and transmitted energy redundancy of frequency shared MIMO OFDM radar, two OFDM waveform design algorithms are proposed based on the paraunitary filterbanks and iterative clipping plus filtering, and the joint pulse compression and pulse coherent integration is achieved by using arbitrary length OFDM pulse, the interference of different transmitted signals and range sidelobes are also eliminated.4. Under the background of time variable clutter, the range sidelobe suppression and target detection algorithms are studied based on the adaptive phase-modulated(PM) waveform design. The performance evaluate factor and waveform evaluation and selection strategy for single range cell are proposed, the performance of adaptive PM waveform design range sidelobe suppression is improved, and the adaptive PM waveform design can be used in a wider range.5. For the limitation of adaptive PM waveform design which can only be used in a single range cell, by constructing the joint waveform performance evaluate factor for multiple range cells, the range cells selected method and clutter suppression method are proposed, the clutter range sidelobes of multiple range cells can be jointly suppressed.