Waveform with Time and Frequency Interruptions to Reduce the Energy Consumption of a Tracking Radar

Waveforms are usually designed to optimize the radar performance. To this aim, a compromise has to be found between resolution and ambiguities, so that sidelobes have to be controlled carefully. In the particular scenario of a radar tracking a single target in a sparse environment (space based-radar for orbital rendezvous or air-to-air radar operating at high altitude), the constraint of low sidelobes level can be removed. In this paper, we show how releasing this constraint makes it possible to optimize the power consumption of the radar while preserving its precision. An adaptive waveform with binary frequency and time amplitudes, and frequency or time interruptions, is proposed and its efficiency for delay and Doppler estimation is characterized. The results are illustrated in a space rendezvous use case where the efficiency of the radar in transforming energy into information for delay and Doppler estimation can be improved thanks to interruptions. In this example, the proposed waveform enables to save 60% of the transmitted energy for a link budget excess of 1 dB, while a conventional reduction of the pulse width saves 20% of it.