MIMO-OFDM Implementation Using VLSI

The modulation technique which divides the available spectrum into sub-carriers is called OFDM. OFDM when compared with FDMA (Frequency-Division Multiple Access), OFDM uses the spectrum effectively by channel spacing, in this channel signals are spaced closely together and makes the carriers perpendicular to each other, it prevents the interference between a close-spaced carrier channel. OFDM is specifically used for its robustness in channel fading in the wireless communication. In order to make the system flexible, reconfigurable architecture is used as a pre-requisite. The most efficient reconfigurable and reusable architecture is FPGA. OFDM technique is used, for achieving maximum data rate, with help of MIMO systems. Interference between user to user can be observed by every user in MIMO, due to transmission of data over a common channel. To reduce the inter-user-interference, zero-force precoding technique is used at the transmitter. Here, the information is coded and is transmitted over the channels (MIMO), then the information which is received at the receiver has comparatively low Bit Error Rate (BER). The main aim of this project is, to design and implement a base band (BB)OFDM transmitter and receiver on a FPGA hardware. It involves QPSK mapping module, scrambler, encoder, inter-leaver and cyclic prefix insertion modules. This design uses a 64-point FFT or IFFT as one of its main modules. In addition to OFDM, we are using a zero-force-pre-coding technique in this system which will be simulated using Xilinx 14.5 software and verified by using MATLAB 7.1.