A Fast Hopping Frequency Synthesizer for UWB Systems in a CMOS Technology

A 3 to 5 GHz fast hopping frequency synthesizer for multi-band OFDM UWB applications is designed using a 0.18 mum CMOS technology. The frequency synthesizer operates in the mode 1 bands (centered at 3432 MHz, 3960 MHz, and 4488 MHz). Single-sideband mixer up-converts or down-converts the 528 MHz quadrature signals of ring VCO mixing 3960 MHz LC VCO signals. The sideband suppression is less than -32 dBc for 3432 MHz and -26 dBc for 4488 MHz and band switching time from 4488 MHz to 3432 MHz is measured about 2 ns. Phase noise of the LC VCO and the ring VCO is about -110 dBc/Hz and -98 dBc/Hz at 1 MHz offset frequency, respectively. The total power consumption of the proposed frequency synthesizer is about 68 mW with a 1.8 V supply voltage