High frequency atmospheric noise mitigation

The performance of high frequency (HF) radio communication and radar systems can be limited by noise generated by sources external to the receiving antenna. Below 10 MHz, atmospheric noise generated by worldwide thunderstorm activity tends to be the dominant natural source. We present an empirical analysis of atmospheric noise cancellation achieved by applying an adaptive sidelobe canceller to wideband HF signals measured using the MITRE Texas Facility. We couple our empirical analysis with predicted results obtained using CCIR noise models to assess the likelihood of obtaining significant levels of noise cancellation. We also describe cancellation performance as a function of the degrees of freedom applied and variations in data block size