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Idenya cognitive radio ini sebenernya untuk mengatur resource (frekuensi) seefisien mungkin ditengah semaraknya bermacam-macam teknologi wireless. Ini ada beberapa catatan fundamental yang mungkin bisa memberikan gambaran. Kalau tertarik silakan browsing di internet, atau bisa menghubungi saya, karena ada beberapa referensi bagus yang saya punya.

 

Important Note:

1. CR simplified view
   1. Cognitive radio adapt to spectrum environment
   2. SDR adapt to network environment 
2. What is Cognitive Radio
   1. Tune to any available channel in the target band
   2. Establish network communications and operate in all or part of the channel
   3. Implement channel sharing and power control protocols which adapt to spectrum occupied by multiple heterogeneous network
   4. Implement adaptive transmission bandwidth, data rate, and error correction schemes to obtain the best throughput possible
   5. Implement adaptive antenna steering to focus transmitter power in the direction required to optimized received signal strength
3. Two protocols have emerged as early cognitive radio behavior
   1. Dynamic Frequency Selection

                                                              i.      Originally used to describe a technique to avoid radar signal by 802.11a networks which operate in the 5GHz U-NII band

                                                             ii.      Now generalized to refer to an automatic frequency selection process intended to achieve some specific objective (like avoiding harmful interference to a radio system with a higher regulatory priority)

           b.  Transmit Power Control

                                                              i.      Originally a mechanism for 802.11a network to lower aggregate transmit power by 3dB from the maximum regulatory limit to protect ESSS (Earth Exploration Satellite System) operations

                                                             ii.      Now generalized to a mechanism that adaptively sets transmitter power based on the spectrum or regulatory environment 

   4. Another key cognitive radio behavior is incumbent profile detection (IPD)

1. IPD is the ability to detect an incumbent user (one with regulatory priority) based on a specific spectrum signature
2. DFS requires an IPD protocol identify unoccupied, or lightly used frequencies
3. IPD includes detection schemes focused on the characteristics of the specific incumbents in the band, or bands, that the cognitive radio is designed to support
4. IPD eliminates the need for geo location techniques (GPS, etc) to determine the location of the radio and, using a database, identify unused channels

Reference:

“Cognitive Radio Emerges from Obscurity”, John Notor, January 23, 2004