NARROWBAND BITSTREAM BEAM-FORMER WITH AN INTEGRATED ARRAY OF CONTINUOUS-TIME BANDPASS SIGMA-DELTA MODULATORS

摘要

A new power and area efficient ADC-digital co-design approach is introduced to IF digital beam forming that combines continuous-time band-pass ΔΣ modulators and bit-stream processing. An array of compact (0.03mm2), low-power (13.1mW) delta sigma modulators directly digitizes 260MHz IF signals from eight input elements. Digital beam forming is directly performed on the over-sampled, undecimated low-resolution outputs of the delta sigma modulator array. The unique combination of delta sigma modulators and bit stream processing has several advantages.