摘要：
Fast sensing is done at the rate of 1ms/Channel, and the sensing results are used to decide if a subsequent fine sensing is needed. Fine sensing is performed on-demand, which allows CR networks to meet the strict QoS requirement by decreasing the rate of false alarms. 阅读全文
摘要：
TDM vs. TDMA:TDM stands for Time Division Multiplexing while TDMA stands for Time Division Multiple Access .The main difference between them is as follows :For both systems ,the user is given a certain time slot through which his data is to be transmitted then the user waits for the next frame to tr 阅读全文