Project 25 (P25) refers to a group of standards originally introduced several decades ago by the Association of Public-Safety Communications Officials (APCO) to enable interoperability between federal, state and local public safety agencies in North America. The standards ensure that radio equipment from various manufacturers will be able to communicate with one another, as long as they meet the P25 standard.
P25 supports digital voice and data communications and a variety of radio system configurations, including direct mode, repeated, single site, simulcast operation and others. P25-compliant equipment is available in VHF, UHF, 700 and 800 MHz frequency bands. In fact, P25 standards are applicable to existing analog systems as well as digital ones. This allows users to be P25 compliant even if they have yet to migrate to a digital platform.
Houston Community College’s police force, which now has P25-compliant equipment, communicated with a mix of UHF radios prior to 1993, when it became part of the Harris County regional radio network. Operating on the regional network has significantly increased their coverage area and allows them to easily contact other first responders in the event of an emergency.
“We have approximately 10 mutual aid channels. Some [of those channels] reach all the way into Louisiana,” explains Sherwood. Prior to the switchover, police could only communicate within the city of Houston. Areas outside the city were on a simplex frequency, and officers had to be dispatched from those locations.
“Mutual aid channels are channels we can switch to in times of critical emergencies when we may have to intercommunicate with other agencies because of major flooding, hurricanes and other natural disasters,” he explains.
The Harris County regional radio network currently serves nine counties. The system, says Sherwood, is continually growing.
P25 Radios Improve Incident Response on Large Campuses
The importance of P25-compliant radios can not be underestimated, especially on a large campus. For the University of Texas at Austin (UT Austin), joining a regional radio network was the perfect solution to monitoring a campus that can have nearly 100,000 people on it, including students, staff and administrators.
The UT Austin campus has 160 portable radios and 60 mobile radios that are carried by law enforcement officials. Another 242 radios are carried by personnel in administration, emergency management, utilities or facility services. All of these two-way radios are digital and P25 compliant.
“Our system is a cooperative system between the City of Austin, Travis County, University of Texas, Capital Metro – which is our transportation bus service – Austin Independent School District and the Texas legislative security for House representatives for the state,” says Gary Wilks, assistant manager for the Wireless Services Division of the City of Austin. These agencies, he adds, share a common radio frequency template that allows them to easily communicate with one another.
The templates – which determine what frequencies a radio user should use based on his or her profession – simplify incident response.
“[Our radios] are very easy to use, and as we continue to work with our partners within the region, we refine the templates and use continues to get easier and easier,” explains David Cronk, director of emergency preparedness for UT Austin. “Also, multi-agency use of the interoperability tactical channels is something that we continually reinforce.”
In September of 2010, those tactical channels helped multiple agencies respond to a shooting on campus in which a 19-year-old student carrying an AK-47 fired several rounds of ammunition into the air before taking his own life in a campus library.
Other Interoperability Options Are Available
For campuses that require the option of immediate contact with law enforcement, radio manufacturers offer a variety of P25 compatible options.
“If interoperability with police and fire is a need on a day-to-day basis, [P25 radios are] absolutely something that you’re going to look for,” suggests Pour
ciau. “If it’s not needed on a day-to-day basis, or if you don’t have the budget to afford P25-compliant radios, then there are other solutions available.”
An operations critical radio system with a built-in gateway can meet the needs of a campus that may lack the budget to purchase P25 radios, Pourciau adds. Motorola’s Motobridge interoperable IP solution is a gateway that allows different radio systems to communicate with one another, regardless of P25-compatibility.
“A Motobridge is an intelligent gateway that basically sits between different systems and allows different system architectures to talk to each other,” she says. “So a Motobridge could allow a P25 system to talk to one of our MotoTRBO systems, or it could even allow something like a Nextel radio to talk on a P25 network.”
