Guess you didn't even try to read the document
In 1999, the City of Portland began use of its citywide 800 MHz Motorola SmartNet Trunked Simulcast system. The system integrated radio communications for all city departments onto a single technology platform. Since that time some upgrades and modifications to the system have taken place in an effort to meet the communications needs of Portland’s First Responders. The City of South Portland is also a system
participant using the 800 MHz communications infrastructure for their public safety communications.
The time has now arrived to begin planning for the end-of-life cycle for a number of the system components, software and subscriber units that are no longer supported by the manufacturer.