This paper presents the design of a fully integrated 24 GHz injection-locked voltage controlled oscillator (IL-VCO) with a folded Marchand balun and output buffers. The measured oscillation frequency of the IL-VCO covers from to 22.2 to 24.2 GHz, and the locking range at the injection power of 0 dBm is about 2.0 GHz. The total direct current (DC) power consumption is 13.92 mW, including 4.62 mW of the core, from a supply voltage of 1.2 V. The IL-VCO is implemented in 180 nm standard CMOS process. The total chip size is 1.0 × 1.0 mm
. The designed IL-VCO then can be proposed to be applied in a continuous wave (CW) Doppler sensing radar front-end circuit using an injection-locked method.