• P. Vimala

The Cyclic Prefix - Orthogonal Frequency Division Multiplexing (CP-OFDM) primary users is sensed using frequency domain autocorrelation under various channels with noise uncertainty. The spectrum sensing of Cognitive Radio systems plays crucial role to solve current spectrum scarcity. The spectrum sensing using energy detector is the most common method of sensing due to its low computational complexity and easy to implement but its detection performance degrades drastically for primary user signals under low SNR values and in the presence of noise uncertainty. The frequency domain autocorrelation method utilizes Fast Fourier Transform (FFT) and detects an active primary user through the cyclic prefix induced correlation peak estimated from the FFT samples. The performance of the frequency domain autocorrelation is estimated under channels such as AWGN channel, Rayleigh channel and Rician channel with noise uncertainty. It performs well in noise uncertainty contrasting traditional energy detection technique.

Cognitive Radio, CP-OFDM Primary Users, Frequency Domain Autocorrelation, Spectrum Sensing

"CP-OFDM Primary Users Sensing under Various Channels using Frequency Domain Autocorrelation ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 5, page no.509-512, May-2019, Available :http://www.jetir.org/papers/JETIR1905L77.pdf

"CP-OFDM Primary Users Sensing under Various Channels using Frequency Domain Autocorrelation ", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 5, page no. pp509-512, May-2019, Available at : http://www.jetir.org/papers/JETIR1905L77.pdf