Who moved my standard?
We all must navigate through the maze of land mobile radio (LMR) changes, especially in the area of standards. This is made more difficult by the “moving of the standards cheese,” a phenomena that is creating lively debate.
The LMR community has spoken and demanded open standards-based solutions, similar to what’s found in the IP sector. There are several well known and several lesser known LMR standards that address this demand.
Project 25 is a user-defined open standard developed specifically by and for the needs of North American public safety. The European Telecommunications Standards Institute developed TETRA for the public-safety community, but has expanded its reach. The British established MPT1327 in the late 1980s, just as P25 was getting started. It is the most widely used open LMR standard in the world, but is not as well known in North America. MPT’s successor — the open digital mobile radio (DMR) standard — uses TDMA to deliver 6.25 kHz channel efficiency.
So where is the debate?
It seems to be over which standard is suitable for which vertical market. Is P25 suitable for markets outside public safety? Is TETRA suitable for North America public-safety agencies or utilities — or both? What are MPT and DMR anyway and why do I care?
The short answers are: all could be suitable and it depends.
P25 was designed to do a lot of things, including interoperability and encryption. But it also was designed for coverage. The North American market is mostly characterized by large geographies with relatively less population density, especially when compared to Europe. P25 technology needs to be able to provide very similar coverage characteristics to technologies it is replacing.
P25 has features and costs that are less attractive outside of public safety. But there are examples of utilities, oil and gas enterprises, and public-safety agencies outside of North America that selected P25.
In contrast, TETRA was designed more for capacity. There are other technical and commercial issues with TETRA that have been discussed. Even if those hurdles could be overcome, TETRA is at an economic disadvantage, as it requires more sites to cover a given geography as compared with P25, MPT or DMR. But there are applications, such as a large campus, where TETRA may be the best fit.
MPT was designed for scalability and coverage. It can range from one to 960 sites and provides the same coverage as conventional radio. MPT is similar to other digitally accessed technologies such as EDACS or SmartZone. MPT is very popular with utilities and transport verticals. But it is used by some public-safety agencies also.
DMR is the new kid on the block with the standard being first published in 2005. It might seem overly simplistic, but we can refer to DMR as a “digital MPT.” DMR, like P25 and MPT, was designed for coverage. Like TETRA and P25 Phase II, DMR delivers 6.25 kHz channel efficiency. So it is an excellent fit for North America, especially for utility and transport vertical markets.
Which technology is the right fit? It depends. What are your requirements, coverage needs and budget? Debate is good and healthy, as is an informed LMR community. All technologies should be considered — TETRA, P25, MPT and DMR.
Stay alert and be ready. Hey, who moved my standard?
Bill Fredrickson is the senior vice president, global utility sector, for Tait Radio Communications.