Enhanced spectrum sensing techniques for dynamic spectrum access cognitive radio networks

Spectrum access protocols permit secondary users to utilize frequency bands when the bands are not in use by the primary owners. To determine if a frequency band is in use, spectrum sensing techniques (e.g., energy detection, feature detection) are employed by the secondary radios. Such techniques require that the secondary radios cease transmitting in the band during spectrum sensing periods. We propose a technique whereby cognitive radios that are secondary users of a frequency band can monitor the band for the emergence of primary signals while communicating. This enhancement permits more efficient use of spectrum by the secondary network, which results in increased channel utilization.