  This paper proposes a distributed hybrid millimeter wave (mmWave) scheme to
exploit the structure of a Densely Deployed Distributed (DDD)
small-cell-base-stations (SBSs) system for serving multiple users in a
geographic area. Both the SBSs and the users are equipped with full access
hybrid architectures with multi-antenna arrays and multiple radio frequency
chains. Unlike the conventional cellular networks where users receive data
streams from their nearest BSs, the users in our proposed scheme simultaneously
receive data streams from different SBSs. With appropriate design of analog
beamformers, co-channel multi-data-stream interference can be mitigated and the
extra spatial degrees of freedom induced by the geographic distributed SBSs are
exploited for data multiplexing. Analytical and simulation results show that
the proposed scheme can improve the system sum-rate considerably, especially
when the number of scattering components in millimeter wave channels is
limited.
