An integrated beamformer for IR-UWB receiver in 0.18-µm CMOS

This paper presents a fully integrated 2-channel beamformer for 3–5 GHz impulse-based ultra-wideband (IR-UWB) receiver. A true time delay (TTD) element with optimized cutoff frequency and active loss compensation is proposed to provide large continuous time delay tuning with reduced chip size and power consumption. Each beamforming channel has a measured peak gain of 18.5 dB and a continuous time delay between 0–255 ps. The proposed beamformer can provide maximum scan angle of up to ±60° for two antennas with 8 cm spacing. The whole beamformer consumes 38 mA from a 1.8V DC power supply.