4G technology bring great prospects for the future. To obtain the desired goal, a multiplexing technique known as the OFDM i.e. Orthogonal Frequency Division Multiplexing was being suggested. OFDM provides sufficient data rate as other methods but requires less bandwidth. The idea of OFDM was conceptualized in the 60’s. Weinstein and Ebert showed that OFDM can be employed or implemented using Fast Fourier Transform (FFT). With arrival of VLSI and advancement in DSP techniques, OFDM was practically implemented. OFDM has three main problems namely Intersymbol Interference (ISI), PAPR known as Peak-to-average Power ratio and the intercarrier Interference (ICI). One of most severe problem among these is ICI. Efficient methods were proposed to eliminate the ISI and reduce PAPR. This paper explains the factors that causes ICI in the 4G LTE wireless system and possible solutions to this kind of interference. The ICI increases the system probability of bit error rate (BER) increases. The system BER can be reduced by reducing the factors which have significant affects to cause ICI.
- Farhan Altaf is an Electrical Engineer and a Research Scholar at Department of Electrical Engineering, University of Engineering and Technology Peshawar, Pakistan.
- Dr. Syed Waqar Shah is Professor and Chairman, Department of Electrical Engineering, University of Engineering and Technology Peshawar, Pakistan
Farhan Altaf Syed Waqar Shah Waleed Shahjehan Haseeb A. Khan
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