Collision-recovery method for collided OFDM based packets

We present an effective method of collision recovery for orthogonal frequency division multiplexing (OFDM)-based communications. For the OFDM system, the modulated message data can be demodulated using the partial time-domain OFDM symbol. Therefore, the partial time-domain symbol can be adopted to reconstruct the whole OFDM time-domain symbol with estimated channel information. This property can be utilized to recover packets from the collisions. Since most collisions are cases in which a long packet collides with short packets, the collided part is assumed to be short. The simulated results show that the method can recover all packets with different specific probabilities and can be developed to solve the problem of hidden terminals.