  Advanced metering infrastructure (AMI) of smart grid requires bidirectional
communication for transferring data to billing center, for which WiFi is an
attractive choice. However, WiFi operates in the unlicensed bands and LTE needs
to offload data in the same unlicensed band. Recent release of 3.5 GHz (also
termed as citizen broadband radio service (CBRS)) can be an attractive shared
band where LTE and WiFi can coexist. In our study, we propose a fixed duty
cycled LTE-U and WiFi based smart grid metering infrastructure where smart
meter uses WiFi and data collector (termed as Access Point (AP)) of smart
meters uses LTE for transferring data. We investigate the coexistence
performance of LTE-WiFi in the 3.5 GHz band using a time division duplexing
(TDD) LTE confederated by WiFi along with FTP traffic model for system level
simulation. The simulation results demonstrate a good neighboring coexistence
between LTE and WiFi resulting a candidate AMI architecture for smart grid in
the 3.5 GHz band.
