標題: | Overloaded Multiple Access Systems: A Generalized Model and A Low-complexity Multiuser Decoder |
作者: | Chang, Meng-Che Su, Yu T. 傳播研究所 Institute of Communication Studies |
公開日期: | 2016 |
摘要: | Several works have emerged in the past decade that can potentially provide higher spectral efficiency than that offered by existing orthogonal-channelization based air interfaces for a fixed bandwidth expansion factor. Among them, the interleave division multiple access (IDMA) and low-density spreading CDMA (LDS-CDMA) are of special interest because of their overloading capability. In this paper, we present a unified system structure that encompasses both systems. We call this unified structure as codeword interleaved LDS CDMA (cILDS-CDMA) and present an iterative decoding structure. We analyze the decoder performance via an EXIT-chart like approach and demonstrate the advantage of low density (sparse) spreading. Numerical results in AWGN channel show that LDS reduces the decoding latency and the cILDS-CDMA scheme also offer a larger diversity gain in frequency selective fading channels. |
URI: | http://hdl.handle.net/11536/136250 |
ISBN: | 978-1-5090-3401-7 |
ISSN: | 2165-4700 |
期刊: | 2016 9TH INTERNATIONAL SYMPOSIUM ON TURBO CODES AND ITERATIVE INFORMATION PROCESSING (ISTC) |
起始頁: | 231 |
結束頁: | 235 |
顯示於類別: | 會議論文 |