Improving the range/time sidelobes of large bandwidth discontinuous spectra HF radar waveforms

Due to heavy user congestion, many over-the-horizon (OTH) HF radars are restricted to operating within narrow frequency bands. As a result the achievable range resolution with such radars is poor. In order to operate a wideband HF radar, the signal spectrum must be made discontinuous, which gives rise to high range sidelobes and thus a low signal dynamic range. We introduce a new signal processing technique to lower the range sidelobes associated with discontinuous spectra signals. Results are presented for a repeated linear FM test case and show significant range sidelobe reduction using the new algorithm