A Two-Way Wideband Active SiGe BiCMOS Power Divider/Combiner for Reconfigurable Phased Arrays With Controllable Beam Width

Abstract

This paper proposes a reconfigurable two-way wideband active power divider/combiner based on bi-directional amplifier and absorptive series-shunt switch techniques. A multi-octave operational bandwidth and flat gain response with bi-directional operation are simultaneously achieved using bidirectional distributed amplifiers (BDAs). The reconfigurable functionality and fast mode selection are obtained by using the absorptive series-shunt switches. The proposed power divider/combiner provides four different operational states depending on the control inputs for the BDAs and the series-shunt switches. The dual-path mode supports both divider and combiner operations, and the measured gain is greater than 7.8 dB and the isolation between output ports is better than 23 dB over the 3-dB bandwidth of 2-23 GHz. The measured noise figure (NF) of the dual-path mode is below 10 dB, while maximum amplitude and phase imbalances are 0.2 dB and 1.8 degrees, respectively. The single-path mode shows a measured gain of > 7.8 dB, and a port-to-port isolation > 35 dB. The measured NF is below 12 dB from 8 to 26 GHz. In addition, the proposed circuit shows the maximum output 1-dB compression point (OP1dB) of 4.6 dBm, and good matching characteristics, with a DC power consumption of 120 mW. The chip area of the reconfigurable two-way SiGe bi-directional active power divider/combiner is 1.43 mm × 0.92 mm. INDEX TERMS Active power divider/combiner, bi-directional amplifier (BDA), octave bandwidth, phased array antenna, reconfigurable, SiGe, SiGe BiCMOS, wideband.