资 源 简 介
应用背景Massive multiuser MIMO (MISO):
◮ M ≫ K ≫ 1 (think 100 × 10 or 500 × 50)
◮ coherent, but simple, processing
◮ Potential to dramatically improve rate & reliability
◮ Potential to drastically scale down TX power
◮ Not only theory, at least one known testbed (64× ∼10)
关键技术
Massive MIMO Operation
Not enough resources for pilots & CSI feedback, so operate in TDD.
◮ On the uplink,
◮ acquire CSI from uplink pilots and/or blindly from data
◮ detect symbols
◮ M ≫ K ⇒ linear processing (MRC, ZF, MMSE) nearly optimal
◮ On the downlink,
◮ use CSI obtained on the uplink
◮ make necessary adjustments based on reciprocity calibration
◮ apply multiuser MIMO precoding
◮ simple precoders desirable (and very good!): MRT, ZF, MMSE, ...
◮ MRC/MRT operation
◮ intracell interference will appear as
