Enhanced Orthogonal Frequency Division Multiplexing - A Survey

The signal consists of the frequency components and the modulation will be done before the signal is transmitted to the receiver and the reverse process of the modulation known as demodulation will be done at the receiver side. The signal which is received at the receiver must be equal to the signal transmitted at the transmitter. If the signal is not same then the signal will be retransmitted to the receiver. To avoid retransmission and the time delay, the signal must be transmitted with less error. Nowadays, the Orthogonal Frequency Division Multiplexing (OFDM) techniques are used to improve the efficiency of the signal. In this paper, the various techniques that used OFDM for the signal modulation is studied and analyzed to get the best technique for the transmission of the signal, so that the signal received at the receiver will have less error performance, high diversity gain, high signal to noise ratio and high spectral efficiency.