Channel estimation refinement by training sequence extension and interleaver design /


Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Electrical and Electronics Engineering, Turkey

Approval Date: 2014

Student: SAMET GELİNCİK

Supervisor: ALİ ÖZGÜR YILMAZ

Abstract:

Rapid variation of channel coefficients is one of the most challenging problems in wireless communication. To provide and keep communication in desired quality, channel coefficients should be estimated continuously. This can be made by using pilot symbols between data blocks which are known by the transmitter and receiver. The channel coefficients between pilot symbols can be estimated by interpolation but this method has a disadvantage in fast fading channels since the channel coefficient estimates have better quality around the pilot blocks than away from them. To solve this problem, we propose to extend the pilot block by making use of the soft information produced by channel decoder. We track the channel estimates in time by the LMS algorithm bidirectionally so that we can estimate coefficients more accurately by interpolation . We also introduce a new interleaver which divides the bits into subregions based on their proximity to pilot blocks and permutes them within their own region.