In-band interference of multi-band OFDM systems

The impact of time-frequency hopped multi-band orthogonal frequency division multiplexing (MB-OFDM) on in-band wideband receivers is considered. First, we compare direct-sequence and frequency-hopped ultra-wideband (UWB) systems in terms of power and range characteristics. We then show that in-band receivers with large bandwidths are susceptible to UWB systems, but direct sequence systems are potentially less harmful due to the large relative bandwidth. The MB-OFDM signal introduces less interference for long hop lengths, but the signal peak-to-average power rises. This makes the MB-OFDM signal appear impulsive to a victim receiver, causing destructive interference at high signal-to-noise ratios.