Design of a low-complexity wideband analog true-time-delay 5-beam array in 65nm CMOS

Abstract

Non-squinting wideband analog multi-beamformer is proposed using true time delay (TTD) element delay Vandermonde matrix (DVM). Efficient realization of the DVM is achieved by sparse factorization, which leads to low-complexity hardware implementations (i.e. less number of delay blocks). It is shown that the proposed approach saves 36 TTD elements in a 5-beam multi-beamformer (4-beams corresponding to the 4-point DVM plus the direct sum beam) giving rise to a 60% reduction of hardware in the design compared to the direct implementation. Proposed low-complexity 5-beam multi-beamformer uses all-pass filters as the delay element and measured S-parameters from a fabricated 65 nm CMOS all-pass filter is used to compute the array patterns of the proposed design in the 1.6–2.4 GHz range.