tailieunhanh - Báo cáo hóa học: " Research Article Further Development of Synchronous Array Method for Ad Hoc Wireless Networks"

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 Further Development of Synchronous Array Method for Ad Hoc Wireless Networks | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2009 Article ID 873202 14 pages doi 2009 873202 Research Article Further Development of Synchronous Array Method for Ad Hoc Wireless Networks Yuan Yu 1 Yi Huang 1 Bin Zhao 2 and Yingbo Hua1 1Department of Electrical Engineering University of California Riverside CA 92521 USA 2Cinea Inc. 16S. 17th Street Richmond VA23219 USA Correspondence should be addressed to Yingbo Hua yhua@ Received 1 February 2008 Revised 10 May 2008 Accepted 22 July 2008 Recommended by Mary Ingram A further development of the synchronous array method SAM as a medium access control scheme for large-scale ad hoc wireless networks is presented. Under SAM all transmissions of data packets between adjacent nodes are synchronized on a frame-byframe basis and the spacing between concurrent cochannel transmissions of data packets is properly controlled. An opportunistic SAM O-SAM is presented which allows concurrent cochannel transmissions to be locally adaptive to channel gain variations. A distributed SAM D-SAM is discussed that schedules all concurrent cochannel transmissions in a distributed fashion. For networks of low mobility the control overhead required by SAM can be made much smaller than the payload. By analysis and simulation the intranetwork throughput of O-SAM and D-SAM is evaluated. The effects of traffic load and multiple antennas on the intranetwork throughput are studied. The throughput of ALOHA is also analyzed and compared with that of O-SAM and D-SAM. By a distance-weighted throughput a comparison of long distance transmission versus short distance transmission is also presented. The study of D-SAM reveals an important insight into the MSH-DSCH protocol adopted in IEEE standards. Copyright 2009 Yuan Yu et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any .