Synthesis of angle modulated ultra wideband signals based on regenerative sampling

For efficient low power UWB communication and ranging systems, fine grained control of the UWB signal spectral properties is desirable to maximize throughput and SNR at a given power budget and spectral mask. Simple impulse radio modulation techniques like pulse amplitude, binary phase or pulse position modulation usually do not provide the same flexibility and spectral efficiency as more complex angle modulation principles. The generation of angle modulated signals, however, is usually much more complex than for impulse radio transmitters. In this paper, a novel concept for the synthesis of pulsed angle modulated ultra wideband signals based on regenerative sampling is introduced that overcomes the above mentioned contradiction. The concept allows for generating arbitrarily phase modulated pulsed UWB signals with a low-complexity hardware. It is based on a switched injection locked oscillator that samples the phase from a high order harmonic of a phase modulated baseband signal. The signal synthesizer does not require any linear amplifiers or PLLs at RF frequency. This principle brings complex angle modulation to ultra wideband signals while at the same time retaining the feasibility of low power implementation. In this paper, this completely novel signal generation principle is introduced for the first time and its capability is theoretically and experimentally verified.