Frequency Synchronization Using OFDM in Long Term Evolution

-Multi-carrier modulation has been used in many wired and wireless communications. It was used in many military high frequency radios, audio-video broad casting and DSL. Multi-carrier modulation can be digitally implemented using Orthogonal Frequency Division Multiplexing (OFDM).Inter symbol Interference can be completely avoided in OFDM by inserting cyclic prefixes. In OFDM wide band channel breaks into multiple parallel narrow band channels. Fast Fourier transform and Inverse fast fourier transform in the OFDM system makes the circuit simple, cheap and low cost. Long Term Evolution (LTE) introduced by third generation partnership project is an emerging standard for high speed wireless communications. This standard benefits from the OFDM technology in the down link which provides several advantages, includes high bandwidth efficiency, fit to multipath fading and simplicity of equalizer. OFDM in LTE is a candidate for air interface in fourth generation cellular system. OFDM systems in LTE transforms frequency selective wide band channels into a group of non-selective narrow band channels. OFDM is susceptible to disturbances like CFO. Time and frequency synchronization of OFDM avoids the disturbances in OFDM.Thus synchronization is an essential part in the receiver section of OFDM. The VHDL language is used for coding, Synthesis can be done in Xilinx ISE Design Suite 13.2 and simulation can be done with Model Sim 6.3f.