The research of the cooperative OFDM system

The main idea to the OFDM is to divide the channel into many orthogonal sub channels in the frequency, which use parallel transmission sub-carriers to modulate. So that, the signal bandwidth is less than the channel coherence bandwidth, which can effectively eliminate ISI. Cooperative diversity is widely used in wireless communication. By taking the advantage of cooperative communication, we try to combine Cooperative diversity with OFDM. In this paper, key technologies of OFDM system, two types of cooperative protocols to realize cooperative diversity in OFDM systems, and two kinds of combining methods, are proposed. Simulations on two types of cooperative protocols to realize cooperative diversity, on two kinds of combining methods are performed. In addition, we simulated the performance of the cooperative diversity OFDM system with relay nodes located in different locations.