Decoupled maximum likelihood detector of ST-FSK

Combining the advantages of space-time block codes and frequency shift keying, space-time frequency shift keying (ST-FSK) can be ML detected noncoherently under the Rayleigh fading channels while providing full diversity. This paper presents a decoupled ML detection algorithm, which utilizes the orthogonal characteristic of signal. The proposed decoupled ML detector, under ideally known H and appropriate channel estimation, outperforms the noncoherent ML detector when the complexity is greatly reduced at the same time.