Title :
New Spreading Codes for Spectrum Sharing by MC-CDMA Structure in Cognitive Radio Network
Author :
Shahrokh, H. ; Mohamed-pour, K.
Author_Institution :
Dept. of Electr. Eng., K.N.Toosi Univ. of Technol., Tehran, Iran
Abstract :
In multi-carrier based cognitive radio, transmitter must inactive some subcarriers to avoid interference with primary users. This process causes the loss of orthogonality among the spreading codes and therefore the performance of the system reduces. In this paper, a new set of orthogonal code for using in MC-CDMA system is introduced. It will be shown that the length of these codes unlike the Walsh-Hadamard codes can be any integer. The performance of new codes is investigated theoretically and simulation results evaluate the performance of system.
Keywords :
code division multiple access; cognitive radio; orthogonal codes; radiofrequency interference; MC-CDMA structure; Walsh-Hadamard codes; interference avoidance; multicarrier code division multiple access; multicarrier-based cognitive radio; orthogonal code; spectrum sharing; spreading codes; Chromium; Cognitive radio; Downlink; Intersymbol interference; Multiaccess communication; Multicarrier code division multiple access; OFDM; Performance loss; Radio transmitters; Transceivers;
Conference_Titel :
Wireless Communications, Networking and Mobile Computing, 2009. WiCom '09. 5th International Conference on
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-3692-7
Electronic_ISBN :
978-1-4244-3693-4
DOI :
10.1109/WICOM.2009.5305276
