  Channel state feedback plays an important role to the improvement of link
performance in current wireless communication systems, and even more in the
next generation. The feedback information, however, consumes the uplink
bandwidth and thus generates overhead. In this paper, we investigate the impact
of channel state feedback and propose an improved scheme to reduce the overhead
in practical communication systems. Compared with existing schemes, we
introduce a more accurate channel model to describe practical wireless channels
and obtain the theoretical lower bounds of overhead for the periodical and
aperiodical feedback schemes. The obtained theoretical results provide us the
guidance to optimise the design of feedback systems, such as the number of bits
used for quantizing channel states. We thus propose a practical feedback scheme
that achieves low overhead and improved performance over currently widely used
schemes such as zero holding. Simulation experiments confirm its advantages and
suggest its potentially wide applications in the next generation of wireless
systems.
