Channel Estimation Algorithms for OFDM-IDMA: Complexity and Performance

Research output: Contribution to journalArticle


Abstract in Undetermined
In this paper, a number of channel estimation algorithms for iterative receivers are compared for the case of an up-link orthogonal frequency division multiplexing interleave division multiple access (OFDM-IDMA) system. Both pilot based algorithms, used to obtain an initial estimate, as well as semi-blind decision-directed algorithms working as a component of the iterative receiver are considered. Algorithms performing either joint minimum mean square error (MMSE) channel estimation, or iterative estimation using space-alternating expectation maximization (SAGE), are evaluated. The considered algorithms differ in terms of complexity, as well as performance. The main contribution of this paper is to give an overview of different channel estimation approaches for OFDM-IDMA, where the complexity versus performance tradeoff is at the focal point. There is no single channel estimator providing the best tradeoff and our analysis shows how the system load (number of users) and the SNR influence the estimator choice.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Electrical Engineering, Electronic Engineering, Information Engineering


  • discrete prolate spheroidal (DPS) sequences, SAGE, maximization (EM), expectation, algorithm complexity, Channel estimation, OFDM-IDMA
Original languageEnglish
Pages (from-to)1722-1732
JournalIEEE Transactions on Wireless Communications
Issue number5
Publication statusPublished - 2012
Publication categoryResearch