The City of Chicago Office of Emergency Management and Communications has recently released a memo that confirms the city has been forced by a combination of circumstances to migrate all of its public safety radio communications to a digital P25 system.
The memo makes mention of "radio intruders" that forced their hand, and "FCC Mandate" to vacate the T-Band. The entire memo is at the bottom of this article.
For many years, persons unknown to the city have somehow obtained two - way radios and were able to program those radios to operate on the Chicago Police Department radio system.
In recent years there have been a few high profile incidents in which people not authorized to be on their system performed various misdeeds. One system intruder encouraged officers to shoot a suspect they were engaged with during an incident in - progress.
According to ABC 7 Chicago, in reports dated for March 14th and March 21st, 2016, a radio system intruder used a racial slur on CPD frequencies. The City of Chicago responded to these incidents with notification to the FCC and the U.S. Attorney's Office because unauthorized operation on some frequencies without a license or other legal authorization is a federal offense.
What is Apco P25? The P25 Technology Interest Group says this:
"Project 25 (P25) is the standard for the design and manufacture of interoperable digital two-way wireless communications products. Developed in North America with state, local and federal representatives and Telecommunications Industry Association (TIA) governance, P25 has gained worldwide acceptance for public safety, security, public service, and commercial applications.
The published P25 standards suite is administered by the Telecommunications Industry Association (TIA Mobile and Personal Private Radio Standards Committee TR-8). Radio equipment that demonstrates compliance with P25 is able to meet a set of minimum requirements to fit the needs of public safety. The P25 standard was created by, and is intended for, public safety professionals."
Who else can use P25? Other than federal and local public safety agencies, FCC licensed amateur (ham) radio operators use P25 and other digital voice communications. Amateur radio operators must be interoperable with federal and local government agencies because they are listed in the U.S. Department of Homeland Security Emergency Communications Protocols as an emergency communications resource.
The new city P25 radio system is currently scheduled to be in place by 2021. The Chicago Fire Department is currently on a P25 digital system. Chicago's Midway and O'Hare International Airports, city parks, and support services will also migrate to the new radio system, along with the Water Department and other city agencies.
The media and radio monitors will still be able to monitor city communications, as radio receivers that allow reception of P25 have already been on the market for many years, and radio amateurs with a valid FCC License have been using P25 for many years. There is no word on whether or not the city will encrypt communications.
The below image is from the FCC website, and shows that the memo from Chicago OEMC is part of an FCC filing. The City is participating with a "slow growth" plan with the FCC.