  We consider wireless networks of remote radio heads (RRH) with large
antenna-arrays, operated in TDD, with uplink (UL) training and
channel-reciprocity based downlink (DL) transmission. To achieve large area
spectral efficiencies, we advocate the use of methods that rely on rudimentary
scheduling, decentralized operation at each RRH and user-centric DL
transmission.
  A slotted system is assumed, whereby users are randomly scheduled (e.g., via
shuffled round robin) in slots and across the limited pilot dimensions per
slot. As a result, multiple users in the vicinity of an RRH can simultaneously
transmit pilots on the same pilot dimension (and thus interfering with one
another). Each RRH performs rudimentary processing of the pilot observations in
"sectors". In a sector, the RRH is able to resolve a scheduled user's channel
when that user is determined to be the only one among the scheduled users (on
the same pilot dimension) with significant received power in the sector.
Subsequently, only the subset of scheduled users whose channels are resolved in
at least one sector can be served by the system.
  We consider a spatially consistent evaluation of the area multiplexing gains
by means of a Poisson Point Process (PPP) problem formulation where RRHs,
blockers, scatterers and scheduled user terminals are all PPPs with individual
intensities. Also, we study directional training at the user terminals. Our
simulations suggest that, by controlling the intensity of the scheduled user
PPP and the user-pilot beam-width, many fold improvements can be expected in
area multiplexing gains with respect to conventional spatial pilot reuse
systems.
