IEEE PROJECTS ON COGNITIVE RADIO

Cognitive Radio (CR) is an adaptive, intelligent radio and network technology that can automatically detect available channels in a wireless spectrum and change transmission parameters enabling more communications to run concurrently and also improve radio operating behavior.

Cognitive radio uses a number of technologies including Adaptive Radio (where the communications system monitors and modifies its own performance) and Software Defined Radio (SDR) where traditional hardware components including mixers, modulators and amplifies  have been replaced with intelligent software.

The main features of the cognitive radio are:

• A transceiver can determine its geographic location.

• It can identify and authorize its users.

• It can perform encryption and decryption.

• Able to sense nearby wireless devices.

• It can adjust its output.

Types of Cognitive Radio

Depending upon certain parameters and transmission there are two types of cognitive radios:

• Full cognitive Radio – It takes into consideration all the possible parameters that can be observed by a wireless node. It is also known as Mitola Radio.

• Spectrum-Sensing cognitive Radio – It detects channels only in the radio frequency spectrum.

Functions of Cognitive Radio

Following are the main functions of Cognitive Radio:

1. Power Control – Power control is used so that the capacity of the secondary users is maximized along with applying certain constraints to protect the primary users.

2. Spectrum Sensing – A cognitive radio can sense empty spectrum without causing any form of interference to other users. There are three spectrum-sensing techniques:

• Transmitter Detection

• Energy Detection

• Cyclo-stationary feature detection

3. Wideband Spectrum Sensing – In this the spectrum sense over large bandwidth over hundreds of MHz or even GHz.

4. Null space based Cognitive Radio – Cognitive Radio can detect null space of the primary user using multiple antennas. It can then transmit in this null space causing less interference to primary user during transmission.

5. Spectrum Management – Cognitive Radio captures the best spectrum that is available to meet the user requirements for communication.

Architecture of Cognitive Radio

While doing M.Tech thesis in Cognitive Radio you will get to know the architecture of this network. There are two subsystems of Cognitive Radio: a Cognitive Unit,

a Spectrum Sensing Subsystem

A Cognitive Unit makes decisions based on various available inputs. A flexible SDR unit provides operating modes using operating software. A spectrum sensing subsystem measures the signal in the environment and detects the presence of other users and services. This whole system is not a single equipment instead it is spread over the wide range of network.

The Cognitive Unit is further separated into two parts – Cognitive Engine and Policy Engine.

The first part ‘Cognitive Engine’ tries to find the solution and defines the radio’s current internal state and the environment in which it is operating based on the inputs. The second part ‘Policy Engine’ ensures that the solution that is provided by the first engine(Cognitive Engine) is in agreement with the rules and policies outside to radio.