Roundtable Hashes Out P25 Phase 2 Benefits and Challenges
Wednesday, October 26, 2011 | Comments
About 16 public-safety professionals came together for a roundtable discussion on Project 25 (P25) Phase 2 last week, covering topics from technology migration to regulatory issues to secure communications to data applications.
Tait Radio Communications sponsored and hosted the event, and MissionCritical Communications was the exclusive media partner.
The discussion began with the question of whether P25 Phase 1 has met its objectives. Some users said it hasn’t because different P25 platforms and revisions from different vendors aren’t interoperable. Atlanta and Los Angeles were two cities that were named as having numerous P25 Phase 1 systems that can’t talk to each other.
“That’s not the standard’s fault,” said Craig Jorgensen, president of Quantum Telecommunications and former co-chair of the P25 Steering Committee. “That’s more a problem of users not having good planning in place.”
End user participation and education was a large theme throughout the discussion. “Standards are missing best practices,” said Mark Schroeder, Arizona Association of Public-Safety Communications Officials (APCO) International frequency advisor and Region 3 700 MHz planning committee chair. “Governance agreements aren’t a good way to manage best practices. Each agency is following its own practices. That’s what’s missing with P25 — it’s great technology but loose on management practices.”
Moving to the next phase of P25, which includes a migration from Phase 1 FDMA technology to Phase 2 TDMA technology, is driven by spectrum congestion, future proofing a system with the latest technology and the FCC’s pending 6.25-kilohertz migration for 700 MHz public-safety spectrum users.
“We’re getting a user understanding that it’s a migration and not a total swap,” said Frank Kiernan, director of the city of Meriden (Conn.) Public Safety Dispatch. “It’s incumbent on the user to learn and know the technology.”
The 2017 migration date for 700 MHz is a large factor, said participants. “The Kansas regional planning committee (RPC) has people running from 700 MHz because of the 2017 date,” said Jason Moses, the interoperable communications coordinator for the Kansas Office of Emergency Communications.
Schroeder agreed the pending date is a problem. “Our city is heavily invested in Phase 1, and we’re part of a regional system,” he said. “The cost to convert our system to Phase 2 is millions of dollars, and the city has enough spectrum so there is no need to migrate.”
He said the RPCs are the best judges of when to move to Phase 2 technology, not the FCC. “When the technology is ready, the market will drive it,” Schroeder said. “The RPCs should be in control of moving from P25 Phase 1 to Phase 2.
The state of Mississippi has a different outlook, said Johnnie Bailey, program manager for the Wireless Communication Commission. “We’re going to Phase 2 next year to ensure we don’t run out of bandwidth,” Bailey said. “We don’t need the spectrum efficiency now, but we will. But the primary reason is to give our users a similar platform for interoperability.”
Richard Martin, communications, special operations for the Michigan State Police, said his agency will have to replace the majority of its radios to move to P25 Phase 2. Other attendees said a vendor promised them that certain Phase 1 radios they purchased would be upgradable to Phase 2 but later the vendor decided it wouldn’t upgrade the radios.
Bailey said a vendor sold the state Phase 2-capable products, but there was an additional cost to turn on the Phase 2 capability. “That’s deceptive marketing in my opinion,” he said.
Neil Horden, chief consultant with Federal Engineering, said putting those details and promises into contracts to hold vendors accountable is key to system planning and deployment. Participants also discussed how proprietary features creep into a network over time if one agency deploys a piece of equipment that might adhere to the P25 standard but has proprietary features as well. “The Phoenix system started as a P25 system, and now it’s a proprietary system [in terms of the infrastructure],” said Schroeder.
Bailey said vendors have offered agencies on the Mississippi network “free” encryption. As the network administrator, he mandates Advanced Encryption Standard (AES) and if an agency wants different encryption, that buyer will be tied to the manufacturer that provides it. “We don’t allow encryption on interoperability talk groups,” he said. “The network is managed by talk groups.”
Some participants said they have concerns, including interference, decreased reliability and coverage, with moving to P25 Phase 2. “I’m leery of TDMA and the noise floor inside buildings,” said Ken Shearen, senior communications engineer for the South Bay Regional Pubic Communications Authority in California.
Steve Macke, principal at Advent, said third harmonic intermodulation issues are arising in some tests that could be a big problem.
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