Differential quadrature phase-shift keying (DQPSK) is one of the most attractive advanced modulation format in these years, because it has a good spectral efficiency. The DQPSK can transmit two bits per symbol, and it has twice the spectral efficiency of the differential phase-shift keying (DPSK). This master thesis focuses on to study the DQPSK performance in the long-haul transmission with the wavelength-division multiplexing system (WDM). The WDM multiplexes multiple optical carriers in the single optical fiber using the different wavelength lasers to carry the signal.
For the experiment, the DQPSK needs a little special technique to conduct. When a delay demodulator is used for the DQPSK signal, an encoder or decoder is required to make the received serial data to be the same as the transmitted serial sequence. As an electrical encoder or decoder is difficult to realize, a software to calculate encoded pattern or decoded sequence is prepared for the experiment. Then, calculated pattern is installed into the error detector, and it is used to measure the bit error rate.
Finally, the performance of the different channels of the WDM DQPSK transmission is measured experimentally. The transmission distance is 495km for the straight line experimental setup.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0723109-020101 |
| Date | 23 July 2009 |
| Creators | Li, Chien-lin |
| Contributors | Wood-Hi Cheng, Hung-Wen Chang, Hidenori Taga, Chin-Ping Yu |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0723109-020101 |
| Rights | off_campus_withheld, Copyright information available at source archive |
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