Nc-ofdm for a cognitive radio

Abstract

The present invention is directed to a cognitive radio device. The device includes a spectrum sensing portion configured to identify idle subcarrier blocks corresponding to non-contiguous channels within the plurality of predetermined channels, a mapping portion configured to encode a transmission message signal into a series of transmit frequency domain samples and map each of the transmit frequency domain samples into an idle subcarrier block, the mapping portion being configured to map each of the transmit frequency domain samples into an idle subcarrier block on a symbol-by-symbol basis, a transmit Fourier transformer configured to transform the series of transmit frequency domain samples into a time domain signal corresponding to a transmit RF waveform, and a transmitter portion configured to upconvert the time domain signal and transmit the transmit RF waveform.

What is claimed is: 
     
         1 . A cognitive radio device comprising:
 a spectrum sensing portion configured to identify idle subcarrier blocks corresponding to non-contiguous channels within the plurality of predetermined channels;   a mapping portion configured to encode a transmission message signal into a series of transmit frequency domain samples and map each of the transmit frequency domain samples into an idle subcarrier block, the mapping portion being configured to map each of the transmit frequency domain samples into an idle subcarrier block on a symbol-by-symbol basis;   a transmit Fourier transformer configured to transform the series of transmit frequency domain samples into a time domain signal corresponding to a transmit RF waveform; and   a transmitter portion configured to upconvert the time domain signal and transmit the transmit RF waveform.   
     
     
         2 . The device of  claim 1 , wherein the spectrum sensing portion includes the activity detector. 
     
     
         3 . The device of  claim 1 , wherein the spectrum sensing portion is configured to upload channel identification data provided by an external database, the channel identification data including the identity of the idle subcarrier blocks. 
     
     
         4 . The device of  claim 1 , wherein the series of transmit frequency domain samples are comprised of orthogonal frequency division multiplexed (OFDM) signals. 
     
     
         5 . The device of  claim 4 , wherein the series of frequency domain samples are modulated by a predetermined modulation technique to encode the message signal, the predetermined modulation technique being selected from a group of modulation techniques that includes frequency shift keying (FSK), phase shift keying (PSK) and quadrature amplitude modulation (QAM).