An all-digital pulse generator in a standard 0.13- CMOS technology for communication systems using an impulse radio ultrawideband signal is presented. A delay-line-based architecture utilizing only static logic gates for pulse generation with low-power characteristic is proposed in this brief. The center frequency and the fixed bandwidth of 500 MHz of the output signal can be digitally controlled to cover three channels in the low band of UWB spectrum. Delay-based binary phase shift keying and pulse position modulation schemes are exploited at the same time to modulate transmitted signals with further improvement in spectrum characteristics. The total energy consumption is 48 pJ/pulse at 1.2-V supply voltage without static bias currents.