A 25-GHz Compact Low-Power Phased-Array Receiver With Continuous Beam Steering in CMOS Technology

A compact low-power phased array receiver with continuous beam steering is presented based on the subsector beam steering technique. The entire beam steering range is divided into five subsectors from four characteristic beams of the Butler matrix. In each subsector the receive beam is steered by weighted combination of the received signals from array antennas. The theory of beam steering is detailed and the relationship of the steered angle with the beam steering factors is derived. The proposed architecture has lower circuit complexity and less power consumption because no challenging CMOS 360° variable phase shifters and multi-phase voltage-controlled oscillators are required. The phased array MMIC implemented in 0.13 μm CMOS technology has 17-21 dB receiving gain and 8.9-10.7 dB noise figure in 25-26 GHz. It consumes lower than 30 mW and takes a small chip area of 1.43 mm². The continuous beam steering is demonstrated over the spatial range from -90° to +90°.