A low phase error X-band eight-channel SiGe PIN diode phased array receiver

A low phase error X-band eight-channel SiGe PIN diode phased array receiver for 9.5-11.5 GHz application has been proposed and fabricated in a commercial 0.18-μm SiGe BiCMOS process. High performance PIN diode switches used in phase shifters ensure low phase error for all phase states. The 9.5-11.5 GHz receiver, which consists of LNAs, VGAs, PIN diode passive phase shifters and active combiners, achieves over 10 dB measured average gain, less than 5 dB NF (at max. gain and ref. phase state) per channel. The RMS gain error is less than 1 dB and the RMS phase error is less than 4.8° at 9.5-11.5 GHz for all phase states. To the authors´ best knowledge, this receiver achieves the lowest RMS phase error in multi-channel X-band phased array receivers using passive phase shifting method.