CSMA evaluation and enhancement with physical layer imperfections
نویسنده
چکیده
CSMA (carrier sense multiple access) is random access protocol for multi-user data communication; it was development to be used in wired (Ethernet) systems, and eventually adopted as the main access scheme of wireless LANs. Because of some intrinsic imperfections and unpredictability of wireless channel, pure CSMA system can not completely use the channel resources; the methods offered in the 802.11 protocol attempt to resolve these issues, namely, imperfect carrier sensing, hidden terminal and exposed terminal problems.
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