Wideband digital beamforming (WDBF) technology is a key for the rapidly developing wideband digital array radar (WDAR). In this paper,by comprehensively considering the characteristics of WDAR and the current hardware and software capabilities for radar in engineering, several practical WDBF technologies based on accurate digital true time delay (TTD) are studied. WDBF technology at radio frequency (RF) is applied and tested on a WDAR test-bed. Besides, WDBF technologies at baseband by implementing fractional delay filers at element level and subarray level are presented and simulated.
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