Directive antenna diversity reception for an adaptive modulationsystem in land mobile communications

摘要

The Letter proposes a directive antenna diversity reception scheme for an adaptive modulation /TDMA/TDD system to achieve high quality, high bit rate and high spectral efficient data transmission even in high mobility land mobile communication environments. In mobile stations, a directive antenna diversity is applied to reduce the Doppler spread equally in each branch. At each branch, the offset frequency (foff ) and foff-cancelled fading variation are estimated to improve the accuracy of the propagation path characteristic estimation even in high maximum Doppler frequency (fd) environments. Computer simulation confirms that the proposed scheme can achieve successful variable rate transmission in fast fading environments