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Báo cáo hóa học: " Research Article Fast Burst Synchronization for Power Line Communication Systems"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Fast Burst Synchronization for Power Line Communication Systems | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2007 Article ID 12145 15 pages doi 10.1155 2007 12145 Research Article Fast Burst Synchronization for Power Line Communication Systems Gerd Bumiller1 and Lutz Lampe2 1 iAd GmbH 90613 Grofhabersdorf Germany 2 Department of Electrical and Computer Engineering University of British Columbia Vancouver Canada V6T1Z4 Received 1 November 2006 Accepted 28 February 2007 Recommended by Halid Hrasnica Fast burst synchronization is an important requirement in asynchronous communication networks where devices transmit short data packets in an unscheduled fashion. Such a synchronization is typically achieved by means of a preamble sent in front of the data packet. In this paper we study fast burst synchronization for power line communication PLC systems operating below 500 kHz and transmitting data rates of up to about 500 kbps as it is typical in various PLC network applications. In particular we are concerned with the receiver processing of the preamble signal and the actual design of preambles suitable for fast burst synchronization in such PLC systems. Our approach is comprehensive in that it takes into account the most distinctive characteristics of the power line channel which are multipath propagation highly varying path loss and disturbance by impulse noise as well as important practical constraints especially the need for spectral shaping of the preamble signal and fast adjustment of the automatic gain control AGC . In fact we regard the explicit incorporation of these various requirements into the preamble design as the main contribution of this work. We devise an optimization criterion and a stochastic algorithm to search for suitable preamble sequences. A comprehensive performance comparison of a designed and two conventional preambles shows that the designed sequence is superior in terms of a fast burst synchronization in various transmission environments b fast AGC adjustment and