Robust TC-OLA Reception With Frequency Domain Equalization for Ultrawideband (UWB) Applications

A variant of time-compression overlap-add (TC-OLA) is proposed as an alternate physical layer scheme for ultrawideband communications. Although the construction of the transmitted signal is identical to other TC-OLA applications, this letter explores block-based receiver structures using frequency domain equalization (FDE) techniques that allow for a longer delay spread relative to the window size than time-domain TC-OLA processing. An important and novel contribution of this method is the reduction or elimination of the cyclic prefix (CP) overhead due to the way that redundancy is added to the transmitted signal by the TC-OLA process. Unlike overlap FDE, the CP overhead is eliminated without the increased processing load required to maintain a practically useful bit error rate floor. For very high delay spread channels, such as CM8, a long effective CP length can be obtained without requiring a much longer fast Fourier transform block length to maintain efficiency.