In this paper we investigate the detection algorithms for interleave division multiple access (IDMA) systems in the presence of carrier frequency offsets (CFOs). The existing IDMA detection algorithm is designed under the zero CFO assumption and its performance will be degraded when the CFOs are present. We first extend the existing algorithm to the nonzero CFO case by utilizing effective channel coefficients which take the CFO effects into account. Then we turn to a more practical scenario with imperfect CFO estimates. We propose an algorithm that can cope with the residual CFO effects by integrating the CFO updating into the iterative receiver. Signal-to-interference-plus-noise ratio analysis and simulations show the feasibility and superiority of our proposed algorithms.
Bibliographical noteFunding Information:
This work is in part supported by the National Science Foundation under Grant No. 1129043, the National Natural Science Foundation of China (No. 60902010 and 61172105), the Research Fund of NCRL (No. 2012A03), National Science & Technology Major projects of China (2009ZX03006-008-02 and 2010ZX03006-003-02), and the Program for New Century Excellent Talents in University (NCET-09-0299).
- Carrier frequency offsets
- Soft interference cancelation