Differential space-time coding with offset quadrature phase-shift keying

Differential space-time coding (DSTC) has been well established as a precoding technique that allows maximum likelihood detection of the received symbols without requiring knowledge of channel state information. This type of detection is useful for highly time-varying channels where the resulting cost of channel estimation is high. However, to date, this approach has not been developed for the commonly-used offset modulations that offer improved spectral performance in the presence of nonlinear transmit power amplifiers. This paper illustrates modifications to the DSTC detection strategy for offset quadrature phase shift keying. Furthermore, it is shown that while traditional DSTC achieves a reduced transmission rate, the combination with offset modulation allows full rate transmission if desired.