摘要
Cognitive radio ( CR) is known as an intelligent technology allowing a secondary user ( SU) to occupy a primary user's ( PU's) band when it is idle. Appearance of the idle band may be contiguous or non-contiguous. In other words,the PU's band and the idle band are distributed alternately over the spectrum. Apparently the non-contiguous idle band cannot be fully utilized in this context. This paper proposes an algorithm to solve the problem of low utilization of the non-contiguous idle band and to increase the number of the SU who needs access to the spectrum by a static spectrum aggregation ( SSA) method combined with non-contiguous orthogonal frequency division multiplexing ( NC-OFDM) . The simulation results show that the SSA algorithm realizes at least 70% utilization of the idle band which provides access to the spectrum for as many as 30 SUs as expected.
Cognitive radio (CR) is known as an intelligent technology allowing a secondary user (SU) to occupy a primary user' s (PU' s) band when it is idle. Appearance of the idle band may be contignous or non-contiguous. In other words, the PU' s band and the idle band are distributed alternately over the spectrum. Apparently the non-contignous idle band cannot be fully utihzed in this context. This paper proposes an algorithm to solve the problem of low utihzation of the non-contignous idle band and to increase the number of the SU who needs access to the spectrum by a static spectrum aggregation (SSA) method combined with non-contiguous orthogonal frequency division multiplexing (NC-OFDM). The simulation results show that the SSA algorithm realizes at least 70% utilization of the idle band which provides access to the spectrum for as many as 30 SUs as expected.
基金
Sponsored by the National Natural Science Foundation of China(Grant No.61071104)
National Key Scientific and Technological Project(Grant No.2012ZX03004-003)
Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory(Grant No.ITD-U12004/K1260010)