Blind identification of the modulation types of a reverse link CDMA2000 transmission

For the modulation identification problem of CDMA2000 1x EV-DO Rev.A reverse data channel in low SNR, this paper proposes a joint identification algorithm based on singular value decomposition and cluster analysis. The algorithm identifies a part of the modulation types by the relation between the spread spectrum period and modulation types. Firstly, the algorithm estimates the spread spectrum period by using the singular value decomposition to identify some modulation types on baseband CDMA signal. Then, it recovers the symbols from data channel defined by the standard. Last, the method identifies the other modulation types using cluster analysis on the symbols. Simulations have shown that this algorithm has a good identification performance.