Blind channel order and delay timing estimation in autonomous decentralized network using asynchronous DS-CDMA

Subspace-based blind channel estimation techniques have been investigated to enable high quality CDMA communication. In the case of receiving multiple independent signals modulated by the same spreading code, accurate channel estimation for a single signal without information about channel orders and delay timing may be difficult. However, this issue has not been investigated deeply. In the case of autonomous decentralized network, receiving same spreading code signals can occur. In this paper, we propose a subspace based blind channel order and delay timing estimation method for the same spreading code signals. This method exploits the orthogonality between the signal subspace consisting of signature waveforms and the noise subspace and provides an estimation result for one of the received signals. We evaluated the proposed method in terms of probability of estimation success rate, and showed that the proposed method can achieve proper estimation performance.