Fundamental W-Band InP DHBT-Based VCOs With Low Phase Noise and Wide Tuning Range

In this paper, fundamental W-band voltage controlled oscillators (VCOs) featuring low phase noise and wide tuning range are reported. These monolithically integrated circuits (ICs) are fabricated using an InP/InGaAs DHBT technology, exhibiting cut-off frequency values of more than 250 GHz for both f
_T
and f
_max
. The VCOs in differential topology consist of an oscillator core according to the negative resistance type and an ac-coupled output buffer. A first VCO version features operation frequencies ranging between 88 GHz and 100 GHz. Within this tuning range, phase noise values down to -90 dBc/Hz have been achieved at 1 MHz offset frequency, while single-ended output power values up to +4 dBm were measured, resulting in a total signal power of +7 dBm. A second VCO version shows operation frequencies between 101 GHz and 109 GHz. Within this frequency operation interval, phase noise values down to -88 dBc/Hz have been achieved at 1 MHz offset frequency, while a single-ended output power up to +2 dBm was measured, i.e. a total available signal power of +5 dBm.