Collision Recovery for OFDM System over Wireless Channel

Yafei HOU  Masanori HAMAMURA  

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E90-A   No.7   pp.1312-1322
Publication Date: 2007/07/01
Online ISSN: 1745-1337
DOI: 10.1093/ietfec/e90-a.7.1312
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Multi-dimensional Mobile Information Networks)
Category: 
Keyword: 
OFDM,  collision recovery,  capture effect,  multipacket reception,  hidden terminals,  ad hoc networks,  

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Summary: 
We present an effective method of collision recovery for orthogonal frequency division multiplexing (OFDM)-based communications. For the OFDM system, the modulated message data can be demodulated using the partial time-domain OFDM signal. Therefore, the partial time-domain signal can be adopted to reconstruct the whole OFDM time-domain signal with estimated channel information. This property can be utilized to recover packets from the collisions. Since most collisions are cases in which a long packet collides with a short packet, the collided part is assumed to be short. The simulated results show that the method can recover the two collided packets with a certain probability and can be developed to solve the problem of hidden terminals. This method will dramatically benefit the protocol design of wireless networks, including ad hoc and sensor networks.