A divide-by-4.5 injection-locked fractional frequency divider

In this paper, we report and demonstrate a divide-by -4.5 injection-locked fractional frequency divider using hybrid integrated circuits (PCB process). The presented frequency divider operates at a fundamental frequency of f₀ = 2 GHz, and achieves an operation range of 187 MHz under a sweeping input frequency f_in around 9 GHz. At a supply current of 5.8 mA, the DC power dissipation is 5.3 mW. The achieved phase noise at 100 kHz offset is -89 dBc/Hz under an injection power of P_in = -10 dBm.