In this thesis, symbol timing recovery in MSK signals is investigated making use
of matched filtering. A decision-directed symbol synchronizer cascaded with an
MLSE receiver is proposed for fine timing. Correlation (matched filter) method is
used to recover the timing epoch from the tentative decisions obtained from the
Viterbi algorithm. The fractional delays are acquired using interpolation and an
iterative maximum search process. In order to investigate the tracking
performance of the proposed symbol synchronizer, a study is carried out on three
possible optimum timing phase criteria: (i) Mazo criterion, (ii) the minimum
squared ISI criterion (msISI), and (iii) the minimum BER criterion. Moreover, a
discussion is given about the timing sensitivity of the MLSE receiver. The
performance of the symbol synchronizer is assessed by computer simulations. It is
observed that the proposed synchronizer tracks the variations of the channels
almost the same as the msISI criterion. The proposed method eliminates the cycle
slips very succesfully and is robust to frequency-selective multipath fading
channel conditions even in moderate signal-to-noise ratios.
| Identifer | oai:union.ndltd.org:METU/oai:etd.lib.metu.edu.tr:http://etd.lib.metu.edu.tr/upload/1057348/index.pdf |
| Date | 01 January 2003 |
| Creators | Sezginer, Serdar |
| Contributors | Tanik, Yalcin |
| Publisher | METU |
| Source Sets | Middle East Technical Univ. |
| Language | English |
| Detected Language | English |
| Type | M.S. Thesis |
| Format | text/pdf |
| Rights | To liberate the content for public access |
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