The concept of the ‘cognitive’ radio was originated by Defense Advance Research Products Agency (DARPA) scientist, Dr. Joseph Mitola, and is the ‘next step up’ for software defined radios that are emerging today, primarily in military applications.

Current User

The U.S. Navy is likely to be the largest consumer of software defined radios with the military’s Joint Tactical Radio System Initiative (JTRS) radios following closely behind. For the Navy, the software-based Digital Modular Radio (DMR) is replacing a roomful of radios with a single rack of DMRs. The DMR (Figure 1) is a four-channel, full-duplex system that is essentially four radios in one. Currently operating on submarines and surface ships around the world, the DMR (AN/USC-61) is successfully demonstrating the viability of software defined radios on active duty.

What is cognitive radio?

The cognitive radio, as its name implies, carries a level of cognition or intelligence that permits decision-making and learned patterns of behavior. According to Institute of Electrical and Electronic Engineers (IEEE), the cognitive radio is a radio transmitter/receiver that is designed to intelligently detect whether a particular segment of the radio spectrum is currently in use and to jump into (or out of) the temporarily-unused spectrum very rapidly without interfering with the transmissions of other users.

Some of the radio’s other cognitive abilities include determining its location, sensing spectrum use by neighboring devices, changing frequency, adjusting output power or even altering transmission parameters and characteristics. All of these capabilities, and others yet to be realized, will provide wireless spectrum users with the ability to adapt to real-time spectrum conditions, offering regulators, licensees and the general public flexible, efficient and comprehensive use of the spectrum.

(retrieved on 2-15-07 from http://www.cotsjournalonline.com/home/article.php?id=100206)

JamieBrown - 16 Feb 2007 -- JamieBrown - 15 Mar 2007
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