Noncoherent Detection of TH-CDMA-PPM Signals for Low Rate WPAN

As described in the physical-layer proposals for IEEE 802.15.4a wireless personal area networks (WPAN), ultra wideband (UWB) impulse radio (IR) is a prospective transmission technology for low-rate indoor communications. Time hopping (TH) code division multiple access (CDMA) is considered as an access scheme for multiuser UWB-IR systems. The TH-CDMA system widely addressed in the literature adopts binary phase-shift keying (BPSK) with coherent detection, which requires accurate channel estimation and thus increasing the implementation complexity. This paper suggests using TH-CDMA-PPM (pulse position modulation) with non-coherent detection to simplify the receiver structure. The error performance of the new scheme is analyzed and numerical results are presented for illustration.