24 GHz Low Power VCOs and Analog Frequency Dividers

24 GHz VCOs and frequency dividers with very low power consumption are presented. The circuits are realized as GaAs HBT MMICs. They comprise a VCO with high efficiency >17% and 12% tuning range at only 18 mW DC consumption as well as several frequency dividers. In order to minimize power consumption, the latter use the injection-locked frequency-divider (ILFD) concept. Divider ratios of 2 and 4 are realized, power consumption as low as 25 mW for a divider-by-2 is achieved. This demonstrates the capabilities of the analog concept in realizing dividers for mm-wave frequencies at DC consumption levels far below their digital counterparts