International Research Journal of Engineering and Technology (IRJET) Volume: 04 Issue: 06 | June -2017
www.irjet.net
e-ISSN: 2395 -0056 p-ISSN: 2395-0072
SPECTRUM SENSING IN COGNITIVE RADIO Vinod H. Patil 1 , Palash Doshi2, Sudarshan Dhomeja3, Sonali Thakur4 Dept. of Electronics and Telecommunication, Bharati Vidyapeeth Deemed University College of Engineering, Pune
--------------------------------------------------------***------------------------------------------------------Abstract - Cognitive radio is the “intelligent radio” that provides increased bandwidth to mobile users by using dynamic spectrum access technique without compromising the licensed band allotted to every organization. It is software defined radio. Cognitive radio faces many challenges because of fluctuating nature of available spectrum as well as distinct Quality of Service required by different applications. Cognitive radio helps to identify the spectrum which is unused. The idea behind this article is to develop an understanding and discuss about the idea of Cognitive Radio.[1] Various spectrum sensing techniques are discussed in this paper.
1. INTRODUCTION Keeping the need of consumers in mind and reduction in data cost, increasing the efficiency and interest in wireless communication system, the demand of cognitive radio has increased drastically. Every operator is provided with a distinct licensed band within which they operate in a certain band of frequency. However, many spectrum bands have already been assigned to many operators, so it becomes a bit difficult to identify the vacant band or even switch the already existing one. Cognitive radio solves the problem of congestion which arises due to over usage of spectrum and provides higher data rate transmission and reception.[2] There are number of ways in which available spectrum band can be exploited. Analog TV
Digital TV
Wireless mics
Sensitivity
-94dBm
-116dBm
-107dBm
SNR
1Db
-21dB
-12dB
Table 1. Receiver’s sensitivity Requirement Cognitive radio focuses on its ability to measure and sense the physical attributes of radio channel characteristics. This characteristics comprises of available n/w, nodes, policies, and various restrictions during operation. There are basically two types of users that exist in a cognitive network – 1. 2.
Primary users Secondary users
© 2017, IRJET
|
Impact Factor value: 5.181
|
ISO 9001:2008 Certified Journal
|
Page 944