Combined-Waveform Design Method and Its Application in Ultra-Wideband Pulse Shape Multiple Access

In impulse radio ultra-wideband (IR-UWB) systems, Rayleigh pulse and Gaussian monocycle are usually the waveforms used to transmit data. However when all the users in a system transmit an identical waveform, the effects of multi-user interference (MUI) are great and therefore the system bit error rate (BER) is high. In order to reduce the effects of MUI, orthogonal waveforms based pulse shape multiple access (PSMA) is proposed. In this paper, combined-waveform the novel orthogonal waveforms design method based on orthogonal wavelet, is presented and utilized to realize multiple access with time hopping (TH) sequence. Meyer wavelet is used as an example to illustrate how to design a set of orthogonal waveforms by this method. Simulation results show that PSMA using combined-waveform can be used to reduce MUI, decrease receiver complexity compared to other orthogonal waveform based PSMA and reach the goal of adaptive spectrum envelope at the same time