Resource Allocation in a Cognitive Radio System with Imperfect Channel State Estimation
نویسندگان
چکیده
Cognitive radio (CR) is a promising concept for improving the utilization of scarce radio spectrum resources. Orthogonal frequency division multiplexing (OFDM) is regarded as a technology which is well-matched for CR systems. In this paper, it is shown that channel estimation errors can result in a severe performance degradation in a multi-user OFDM CR system. A simple back-off scheme is proposed and simulation results are provided which show that the proposed scheme is very effective in mitigating the negative impact of channel estimation errors.
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عنوان ژورنال:
- J. Electrical and Computer Engineering
دوره 2010 شماره
صفحات -
تاریخ انتشار 2010