Question: In a localized area during low usage periods (e.g., nighttime), what is a potential energy-saving strategy that can be employed among multiple mobile network operators, as per 5G system service requirements?
Option 1: Each operator shuts down a portion of their RAN nodes while maintaining individual network coverage.
Option 2: Operators agree to have only one active network providing service to all subscribers, while others shut down their infrastructure.
Option 3: Regulators mandate the use of renewable energy sources for all RAN nodes during low usage periods.
Option 4: All operators must maintain full network coverage at all times, without any shutdowns.
Explanation: While another cooperative approach exists, Option 1 broadly aligns with an initial energy-saving method - shutting down some RAN nodes during low usage. This can be applied independently by each operator for internal network optimization targeting energy savings in localized areas.