W-Band Silicon-Based Frequency Synthesizers Using Injection-Locked and Harmonic Triplers

Two monolithically integrated W-band frequency synthesizers are presented. Implemented in a 0.18 μm SiGe BiCMOS with f_T/f_max of 200/180 GHz, both circuits incorporate the same 30.3-33.8 GHz PLL core. One synthesizer uses an injection-locked frequency tripler (ILFT) with locking range of 92.8-98.1 GHz and the other employs a harmonic-based frequency tripler (HBFT) with 3-dB bandwidth of 10.5 GHz from 90.9-101.4 GHz, respectively. The measured RMS phase noise for ILFT- and HBFT-based synthesizers are 5.4° and 5.5° (100 kHz to 100 MHz integration), while phase noise at 1 MHz offset is -93 and -92 dBc/Hz, respectively, at 96 GHz from a reference frequency of 125 MHz. The measured reference spurs are <; -52 dBc for both prototypes. The combined power consumption from 1.8- and 2.5-V is 140 mW for both chips. The frequency synthesizer is suitable for integration in millimeter-wave (mm-wave) phased array and multi-pixel systems such as W-band radar/imaging and 120 GHz wireless communication.