Abstract-- This paper studies a multiband mobile communication system to support both high data rate services and wide service coverage, using high and low frequency resources with different propagation characteristics. In the multiband system, multiple frequency bands are managed by a base station and one of the frequency bands is adaptively allocated to a terminal. By limiting the low frequency resources to a terminal not covered by the higher frequencies, the presented multiband system can provide wide coverage area for many terminals, as if all radio resources have low frequency. The numerical results show that the multiband system can support wide coverage for much larger number of terminals. It is also found that an appropriate balance of bandwidths in multiple frequencies is essential for high capacity.