A Novel MIMO-SAR System Based on Simultaneous Digital Beam Forming of Both Transceiver and Receiver

Abstract

Orthogonal frequency division multiplexing (OFDM) chirp waveform, which is composed of two or more successive identical linear frequency modulated sub pulses, is a newly proposed orthogonal waveform scheme for multi-input multi-output (MIMO) synthetic aperture radar (SAR) systems. However, according to the waveform model, there will be range ambiguity if the mapping width exceeds the maximum unambiguous width determined by the transmitted signal. This greatly limits its application in high-resolution wide-swath (HRWS) remote sensing. The traditional system divides the echoes by digital beam forming (DBF) to solve this problem, but the energy utilization rate is low. A MIMO-SAR system using simultaneous digital beam forming of both transceiver and receiver to avoid range ambiguity is designed in this paper. Compared with traditional system, the novel system designed in this paper obtain higher energy utilization and waveform orthogonality.

Ultra-High Resolution Imaging Method for Distributed Small Satellite Spotlight MIMO-SAR Based on Sub-Aperture Image Fusion

“…Multiple-input multiple-output synthetic aperture radar (MIMO-SAR) overcomes the contradiction between high resolution and wide swath of single-channel SAR, and is the key development direction of spaceborne SAR in the future [ 1 , 2 , 3 , 4 , 5 ]. Phased array technology is a main way to realize spaceborne MIMO-SAR operation mode [ 6 , 7 ], but it greatly increases the development cost of radar.…”

An X-Band CMOS Digital Phased Array Radar from Hardware to Software

“…Categorized into analog, subarray digital, and element-level digital topologies [1], phased array systems accomplish spatial filtering and power combination through the synchronous excitation of each radiating element. In particular, element-level digitization provides opportunities for sophisticated signal processing and simultaneous reception of multiple beams, which are absent in both analog and subarray digital topologies [2][3][4][5][6][7][8]. Directional and fast-scanning characteristics render phased arrays an attractive approach for various applications, including field surveillance, wireless communication, and electronic warfare [9].…”