부산대학교 도서관

Distributed coordination of operating frequencies and bandwidths is one of the key challenges in the development of dynamic spectrum access (DSA) technology. The spectrum efficiency of DSA networks is achieved through the use of spectrum white spaces, frequency bands which are unoccupied at a given time and place. The issue of frequency rendezvous arises as the availability of these white spaces may change dynamically in frequency, time and space. We propose a novel solution to the problem of distributed rendezvous in dynamic spectrum access networks using cyclostationary signatures . By embedding a cyclostationary signature or watermark in a transmitted signal, the received signal can be uniquely detected, classified, and used for frequency acquisition by distributed dynamic spectrum access-enabled nodes in a network. This paper therefore makes three key contributions. First, a solution to the problem of distributed rendezvous in DSA networks using the novel concept of cyclostationary signatures is presented. Second, a low-complexity technique for generating these cyclostationary signatures in OFDM (orthogonal frequency division multiplexing) waveforms is described. Finally, an initial performance analysis of an implemented test platform is discussed.