A CMOS ultra-wideband (UWB) transmitter in 0.11μm process is presented for 6-10 GHz applications. In order to decrease energy consumption, the proposed Gaussian transmitter adopts a gated voltage-controlled oscillator (VCO) which directly drives 50 Ω output impedance. A gated VCO using a trapezoidal pulse for on/off gating of tail current source satisfies the spectrum mask without need additional pulse shaping filter. The active energy consumption is 13.4 pJ/pulse at 40 MHz pulse repeating frequency (PRF). The performance of side-lobe rejection is more than 30 dB.
