Adaptive channel equalization in WCDMA downlink with turbo coding

Receivers based on channel equalization have proven to be one of the most promising candidates for terminal receivers in wideband code-division multiple-access (WCDMA) downlink. The channel equalizers provide multiple access interference (MAI) suppression, and thus ensure adequate receiver performance even with a high number of active users. However, the performance improvement provided by the equalizers in conjunction with a powerful forward error control (FEC) coding has been unclear. The performance of adaptive equalizers is numerically evaluated with 1/3-rate turbo coding, and compared to the performance of the conventional RAKE receiver. The numerical results show significant performance improvement over the conventional RAKE receiver in a Rayleigh fading multipath channel.

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