Linear RF apertures using 2-D analog beam filters

Design approaches for radio frequency (RF) analog realization of two-dimensional (2-D) network-resonant plane-wave filters are discussed. The plane-wave filters having potential applications in electronically scanned wideband beamforming scenarios operate in spatially-discrete temporally-continuous 2-D mixed-domain as described by their recursive input-output relationships. The proposed approaches imply analog array processing architectures consisting of identical interconnected analog modules (AMs). A 65 nm CMOS circuit simulation of a single AM operating at 700 MHz is used to verify the 2-D plane-wave filter response and array pattern in the first approach. An all-pass filter based time delay approximation is used to design the AMs in the second approach, where a prototype CMOS all-pass filter operating at 5.6 GHz is simulated to verify the 2-D plan-wave filter frequency response and array pattern in closed-form.