This paper presents an ultra-wideband (UWB) signal source which features an array of three wideband voltage controlled oscillators (VCO) and is tunable from 3.2 GHz to 22.7 GHz with a relative tuning range of 150 %. The maximum continuous tuning range is 10 GHz and the phase noise is between -106 dBc/Hz and -126 dBc/Hz at 1 MHz offset. The system can operate as a small and low cost frequency synthesizer which generates frequency chirps with a very high chirp bandwidth for FMCW primary radar applications with high range resolution. The ASIC was fabricated using a 130 nm SiGe technology. It employs a prescaler, a totem-pole power amplifier for single-ended high power output and is fully self-biased. The typical power consumption amounts to 300 mW. It occupies a chip area of 1.8 mm².