  A wireless communication system is studied that operates in the presence of
multiple reconfigurable intelligent surfaces (RISs). In particular, a
multi-operator environment is considered where each operator utilizes an RIS to
enhance its communication quality. Although out-of-band interference does not
exist (since each operator uses isolated spectrum resources), RISs controlled
by different operators do affect the system performance of one another due to
the inherently rapid phase shift adjustments that occur on an independent
basis. The system performance of such a communication scenario is analytically
studied for the practical case where discrete-only phase shifts occur at RIS.
The proposed framework is quite general since it is valid under arbitrary
channel fading conditions as well as the presence (or not) of the transceiver's
direct link. Finally, the derived analytical results are verified via numerical
and simulation trial as well as some novel and useful engineering outcomes are
manifested.
