SiGe BiCMOS 4-bit phase shifter and T/R module for X-band phased arrays

Official URL: http://risc01.sabanciuniv.edu/record=b1534365 (Table of Contents)

Current phased array RADAR (RAdio Detection And Ranging) systems conventionally employ transmit/receive (T/R) modules implemented in III-V technologies (such as GaAs and InP) and their usage is mainly restricted to military applications. The next generation phased array systems require thousands of T/R modules with lower cost, size and power consumption. Advances in SiGe BiCMOS process technologies make it a viable option for next generation phased array systems, especially for commercial applications. In the light of these trends, this thesis presents the design of a 4-bit SiGe X-band (8-12 GHz) passive phase shifter and the complete SiGe X-band T/R module, realized in IHP 0.25- m SiGe BiCMOS process. The phase shifter is based on switched lter topology, utilizing a low-pass network for phase shift state and isolated NMOS transistors are used for bypass state. It is composed of 22 , 45 and 90 bits and the 180 bit is realized by cascading two 90 bits. The return loss of each bit is better than 10 dB, the overall phase shifter has an average of 14 dB insertion loss. Minimum RMS phase error of 3 is obtained at 10.1 GHz. RMS phase error is better than 11 at 9.2-10.8 GHz band. The overall phase shifter occupies 0.9 mm2 area, has no DC power consumption and achieves input-referred 1-dB compression point of 15 dBm. The integration of a compact T/R module using the 4-bit phase shifter and the previously developed building blocks such as low-noise ampli er (LNA), power ampli er (PA) and single-pole double-throw (SPDT) switches is presented. The developed SiGe X-band T/R module occupies only 4.9 mm2 chip area. In 9-10 GHz band T/R module achieves a measured gain of 10-11.5 dB in receiver mode and 10.7- 12 dB gain in transmitter mode. A minimum RMS phase error of 5 is achieved at 9 GHz. Noise gure in receiver mode is measured between 4-6 dB while the IIP3 is receive mode is measured as -10.5 dB. Output power at 1-dB compression in transmit mode is 16 dBm. These parameters are achieved with a power consumption of 285 mW.