The LMR-to-LTE transition: revolution vs. evolution
The National Public Safety Broadband Network (NPSBN) that will be built by FirstNet will establish the first common national infrastructure — based on Long Term Evolution (LTE) commercial standards — for use by all public-safety agencies. This includes both the common backbone, or backhaul, and the over-the-air portion that will allow true national interoperability using the 700 MHz spectrum reserved for public safety.
By using the latest commercial standards, public safety will benefit from larger economies of scale to reduce the cost of devices, while also taking advantage of the insatiable demand for smartphones — now and into the future. Public safety can capitalize on the innovation that is happening today in the commercial arena and translate it into technology improvements that specifically apply to police, fire and emergency medical services (EMS). The real question becomes how to transition from the traditional reliance on land-mobile-radio (LMR) technology. Will it be an evolution or a revolution?
Today’s LMR networks provide the reliability, coverage and dedicated priority in times of emergency that are a must for any public-safety operation. Most public-safety professionals rely on these system characteristics, and the NPSBN must embed these requirements in any future system.
Traditionally, public safety has evolved very slowly, because it has moved slowly to adopt new technologies. However, a revolution—a migration away from current LMR technology as quickly as possible—might be the better choice, if it is executed as part of a strategic, cost-effective and planned effort. This effort would eliminate the reliance on what we love about current LMR systems for the incredible possibilities of LTE, with similar reliability. The largest hurdles will be establishing governance and defining the standards for FirstNet early in the process, in order to create a robust and reliable network.
Given the pace of technology advancements in the cellular industry, a well-planned revolution can save billions of dollars over time, as public safety makes end-of-life decisions on many LMR systems throughout the nation. Public safety can choose a path—with FirstNet providing strategic steps forward—that will allow the nationwide LTE network to eventually replace aging LMR systems (see Figure 1).
This idea may meet with resistance. Current public-safety equipment manufacturers hope to create two systems — and two sets of handheld devices — to generate more income. Further, many believe that voice over LTE will not be as reliable or robust as LMR voice — a debate similar to the arguments for analog versus digital radio systems.
This perception may be based simply on the comfortable reliance on what we all currently know, and the lack of trust in cellular systems that continually fail in major emergencies. The providers freely admit that they did not intend their networks to be used for public-safety emergency operations. As a result, FirstNet will have the opportunity to marry public-safety LMR reliability requirements to the vastly more robust capabilities of LTE.
The most significant challenge—and opportunity—will be governance. Today, governance has led to more interoperability issues than technology. Since 9/11, many technologies have been developed to solve interoperability problems, but the turf battles between various agencies have held back efforts to solve these issues. Each agency has preferred vendors and technologies, based on personal experience, and generally is not willing to step out of its comfort zone.
Thus, the world of stovepipe solutions has been the norm rather than the exception. Today’s grant guidelines promote regional approaches, devoid of stovepipe solutions. But in many of these regions, individual agencies put up every imaginable hurdle to avoid giving up their turf. FirstNet will feel the pressure from industry directly — and through its customers — to allow the same proprietary structure that has prevented interoperability in LMR to exist in the LTE space. However, governance issues could be addressed through the states or other larger jurisdictions, and technology challenges could be overcome by analysis of the current commercial market experience.