Analysis Of Ici Using Blackman Gaussian And Kaiser Window Fuctions

Abstract Orthogonal Frequency Division Multiplexing OFDM is technique of multi-carrier modulation in which a single high rate data-stream is first divided into multiple low rate data-streams and is then modulated using sub-carriers. These sub-carriers are orthogonal to each other. Its main advantages are multipath delay spread tolerance high spectral efficiency immunity to Frequency Selective Fading Channels efficient modulation and demodulation process which is performed by computationally efficient Inverse Fast Fourier Transform IFFT and Fast Fourier Transform DFT operation respectively. An important disadvantage of OFDM is the carrier frequency offset which disturbs the orthogonality among the carriers and results Inter carrier interference ICI. The undesired ICI degrades the performance of the system. In Orthogonal Frequency Division Multiplexing OFDM carriers are orthogonally related and hence no guard band is necessary like in Frequency Division Multiplexing FDM. So spectrums of users can overlap which enhances the spectrum efficiency of the network. In this thesis one of the main concern of OFDM inter carrier interference ICI is considered using different window functions in frequency domain in pulse shaping of OFDM data symbols which are considered uncorrelated. It reduces the inter carrier interference ICI power into simply the square magnitude of window function. Here we have taken different window functions for comparing performance of the wireless links in content of ICI power and desired received signal.