A multiuser Ultra Wide Band (UWB) channel suffers seriously from realistic\nimpairments. Among this, multipath fading and interferences, such as\nMultiple Access Interference (MAI) and Inter Symbol Interference (ISI),\nthat significantly degrade the system performance. In this paper, a polar\ncoding technique, originally developed by Arikan, is suggested to enhance\nthe BER performance of indoor UWB based Orthogonal Frequency Division\nMultiplexing (OFDM) communications. Moreover, Interleave Division\nMultiple Access (IDMA) scheme has been considered for multiuser detection\ndepending on the turbo type Chip-By-Chip (CBC) iterative detection\nstrategy. Three different models as Symmetric Alpha Stable (SS), Laplace\nmodel and Gaussian Mixture Model (GMM), have been introduced for approximating\nthe interferences which are more realistic for UWB system. The\nperformance of the proposed Polar-coded IDMA OFDM-based UWB system\nis investigated under UWB channel models proposed by IEEE 802.15.3a\nworking group and compared with Low Density Parity Check (LDPC)-coded\nIDMA OFDM-based UWB system in terms of BER performance and complexity\nunder the studied noise models. Simulation results show that the\ncomplexity of the proposed polar-coded system is much lower than LDPC-coded\nsystem with minor performance degradation. Furthermore, the proposed\npolar-coded system is robust against noise and interferences in UWB indoor\nenvironment and gains a significant performance improvement by about 5\ndB compared with un-coded IDMA-OFDM-UWB system under the studied\nnoise models.
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