A low-power subharmonic injection-locked oscillator using E/D-mode GaAs PHEMTs for Ka-band applications

摘要

A subharmonic injection-locked oscillator (SILO) implemented by using 0.5 mum E/D-mode PHEMT process is demonstrated to achieve a Ka-band low-power and low phase noise source in this paper. Based on a 15 GHz cross-coupled oscillator, a signal having the frequency around 30 GHz can be generated in this SILO circuit through the push-push technique. A cascode amplifier is also arranged to be the output buffer for gaining the output amplitude of 30 GHz signal. The total power consumption of SILO is 24.5 mW under 2.5 V supply voltage. The measured free-running phase noise is -101 dBc/Hz at 1 MHz offset. With injecting a 2nd-order sub-harmonic signal (7.5 GHz) into this ILO, the output phase noise can be further improved to -127 dBc/Hz. The overall frequency multiplication factor is 4.