A GPS SOC with novel fast auto frequency calibration RF PLL

A GPS SOC with auto frequency calibration PLL is designed to obtain fast PLL locking for GPS navigation. An analog and digital algorithm parts complete the whole auto frequency calibration circuits. This work is fabricated by 0.13 μm RF CMOS process, and demonstrating that the VCO frequency tuning range is wider than ±500MHz and the AFC completing time is less than 80us. The SOC acquisition and tracking sensitivity are about -142dBm and 155dBm.