Testing and Evaluation of Modified Dynamic threshold Energy Detection Algorithm for CR Sensing Applications

Authors

  • T. Srinivas   Department of ECE, Aditya college of Engineering, Surampalem, Andhra Pradesh, India
  • B. Jagadeesh Babu  Department of ECE, Aditya college of Engineering, Surampalem, Andhra Pradesh, India
  • G.Bheemeswara Rao  Department of ECE, Aditya college of Engineering, Surampalem, Andhra Pradesh, India

Keywords:

CR, Energy Detection, Noise Uncertainty factor, Probability of detection, Probability of false alarm, Primary user, ROC curve, SNR-wall, Spectrum sensing, Threshold .

Abstract

Nowadays Energy detection via threshold is a complex and multifaceted issue in Cognitive Radio sensing applications. A Cognitive radio (CR) is all time monitoring smart radio which detects available channels in wireless spectrum. The important features of CR are Spectrum mobility, Spectrum sharing, Sensing-based Spectrum sharing and spectrum reuse. CR sensing is used to detect and locate unused area of spectrum and sharing it among many users by following the protocols of EMI & EMC (if possible also senses empty spectrum.). Hence Primary users (PU) detection is Vital for proper spectrum usage. The widely used Spectrum-sensing method is Transmitter detection. It may be of three kinds. It may be usually matched filter detection, sometimes Energy detection and in special cases it is Cyclo stationary featured detection. Among them Matched filter configuration is provided by maximizing peak signal to mean noise ratio but it results many demerits whereas energy detection is the best alternative. The conventional energy detection technique uses fixed threshold. Measurement of RSS (Received Signal strength) in terms of power indicates whether signal is present or not. So Threshold indicates the optimum (minimum) level of signal power for detection. Noise variance information is required to design the proposed energy detector. This is the simple process involved in energy detection. If we don’t know noise power then SNR (Signal to Noise ratio) walls problem comes into picture due to noise uncertainty. This uncertainty obtains poor and un-optimized performance in several cases.

The main Objective of this paper is to address the above discussed problem by implementing a new efficient energy detector to provide best performance in CR sensing applications. i.e. it uses dynamic threshold which uses two threshold levels. The required two threshold values are determined by noise uncertainty factor (NUF). The Receiver operating characteristic (ROC), Monte-Carlo simulation provided the promising results. This algorithm can be suited for various sensing applications with minute modifications. Its main merit is it does not need any information of the signal, estimation of noise and channel powers.

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International Journal of Scientific Research in Science, Engineering and Technology

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Published

2016-06-30

Issue

Volume 2, Issue 3, May-June-2016

Section

Research Articles

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How to Cite

[1]
T. Srinivas , B. Jagadeesh Babu, G.Bheemeswara Rao, " Testing and Evaluation of Modified Dynamic threshold Energy Detection Algorithm for CR Sensing Applications, International Journal of Scientific Research in Science, Engineering and Technology(IJSRSET), Print ISSN : 2395-1990, Online ISSN : 2394-4099, Volume 2, Issue 3, pp.594-599, May-June-2016.