摘要
为了使认知无线电(CR)系统最大限度地利用频谱机会,提出了一种选择感知周期的方法.对于采用正交频分复用(OFDM)的CR系统,联合设计感知器和收发信机,交替进行频谱感知和数据传输,1次感知若干个授权用户子频带.在一定的感知性能要求下,给出了确定基于OFDM的CR系统感知时间长度的方法,并将最优感知周期的选择建模为一个带约束的非线性优化问题.优化结果显示,CR系统在最大限度地利用频谱机会的同时,能满足对授权用户干扰的限制.
The spectrum sensor and transceiver can be jointly designed for the orthogonal frequency-division multiplexing（OFDM）-based cognitive radio. Which does spectrum sensing and transmission alternatively. Furthermore, it can sense multiple licensed bands simultaneously. The time length of sensing can be decided according to the sensing performance requirement. The choice of the sensing period is mod- eled as a nonlinear optimization problem with the constraint of the probability of interference with the licensed users. Through the sensing period optimization, the OFDM-based cognitive radio can take full advantage of the spectrum opportunity and guarantee the lower interference with the licensed users.
出处
《北京邮电大学学报》
EI
CAS
CSCD
北大核心
2011年第3期98-102,共5页
Journal of Beijing University of Posts and Telecommunications
基金
国家科技重大专项项目(2010ZX03003-002-01)
国家自然科学基金项目(60972023)
关键词
认知无线电
正交频分复用
频谱感知
感知周期
cognitive radio
orthogonal frequency-division multiplexing
spectrum sensing
sensing period
