Public Safety Seen as Relying on Conventional Radios for Many Years

“Public safety agencies rely on lifeline mission critical wireless voice operations both during emergencies and during seemingly routine events that could turn into a critical emergency at any time,” the trust said in a filing at the commission. “Public safety’s goal is to add data and video capabilities to its traditional land mobile radio (LMR) mission critical voice capabilities, not to substitute data and video. Experience shows that new tools that increase operational effectiveness and efficiency soon become essential elements in public safety prevention and response activities. Therefore, public safety is planning to begin the multi-year process of deploying broadband with the recognition that the added data and video capabilities will eventually become a high priority as well.” It probably will be many years “before LMR systems are replaced entirely,” the trust said. “Before LMR systems could be supplanted, broadband services would first need to be deployed to the level that provides the same extensive coverage that mission critical voice systems provide, including in-building coverage in many instances.”

The bureau asked which public safety application has the highest required data rate, what the rate is and which has the highest sustained bandwidth requirement. Public safety officials disagreed at the workshop about how agencies would use new broadband capabilities.

“This is a difficult question to answer at this stage because the aggregate data rate requirements depend on many factors, including the number of simultaneous users in a given cell, the frequency of use, etc.,” the public-safety trust said. “These factors are not yet totally known because there are currently no broadband services available to public safety for wide area use and many applications are still in early development stages.” The trust said its “best estimate” is that video uploading and downloading will be “the application with the highest data rate and capacity requirement.” Downloading of geographical information services maps also uses significant bandwidth, it said. “Actual experience will help define the capacity required,” it said. “However, public safety has seldom, if ever, experienced an environment in which it had too much spectrum capacity for the job at hand, especially in major cities.”

The trust will play a role in deciding which users and traffic are allowed on the system and which have priority access in an emergency involving many agencies, it told the bureau. “The PSST has worked extensively with third parties to address these issues and is well-suited to representing the public safety community as the priority access features are developed,” it said. “After the overall priority access framework is established, local public safety entities should have the authority to determine and manage individual priority access assignments in their service areas.”