Cognitive Radio Air Interface key Technology

摘要

The paper describes three basic components being able Cognitive radio: Frequency, Modulation and Power. Frequency is located in 3.1 GHz~10.6 GHz so that the system can sufficiently utilize spectrum resource and UWB communications channel. OFDM in UWB communications is extensively used to mitigate multi-path interference. QPSK and DCM modulation are used to map binary data on signal wave shape on subcarriers. The most promised problem is emission power mask level to reduce interference to primary users. Cognitive Radio that operates in the holes of licensed spectrum could transmit the same level power as license wireless communications.