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A discussion on channel sensing techniques. By James Xu. Energy detection for Cognitive Radio. Presentation overview. Introduction to wireless communications What is Cognitive Radio (CR)? Why do we need CR? What is energy detection Our workbench Standard energy detector
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A discussion on channel sensing techniques By James Xu Energy detectionfor Cognitive Radio
Presentation overview • Introduction to wireless communications • What is Cognitive Radio (CR)? • Why do we need CR? • What is energy detection • Our workbench • Standard energy detector • Problem with the detector • Our improved detection model
What is Cognitive Radio (CR) • Able to sense spectral environment • Able to provide opportunistic access • Find gaps in the spectrum • Adjust system parameters to utilize it
Why do we need CR? • Unlicensed spectrum is scarce • Almost none available under 3GHz
Why do we need CR? • Licensed to primary user only (Incumbent) • We are running out of space, and higher frequency has problems • We are under utilizing licensed space • CR is allowed usage (guarantee interference free)
Energy detection • The first step in CR is to identify free spectrum • Energy detection is being used
What is energy detection? • All radio transmission have energy • Based on hypothesis testing
Problems with the detector • Misdetection on Narrowband signals
Problems with the detector • Misdetection on partial signals
Adaptive energy detection • We proposed an improvement • Introduced adaptive detection
Thank you for listening • Any questions?