3.1 Paradigm Change for the Delivery of PPDR Broadband Communications
In most parts of the world, the prevailing model being used nowadays for the delivery of mission-critical narrowband PPDR communications (mainly voice-centric and low data rate services) can be well described by the following principles:
- Use of dedicated technologies. As discussed in Chapter 1, PPDR communications today rely mostly on the use of PMR technologies (e.g. TETRA, TETRAPOL, DMR, P25), most of them conceived in the 1990s in parallel with the second generation (2G) of mobile communications systems (e.g. GSM).
- Use of dedicated networks. Networks deployed for PPDR use are mainly private, dedicated networks that are built and operated with the specific purpose to serve the PPDR communications needs of a single agency or a number of them. Use of these systems by other non-PPDR users is rather limited or even not allowed in most cases.
- Use of dedicated spectrum. The operation of current narrowband PPDR networks is based on the use of dedicated spectrum, which is specifically designated for PPDR use.
This delivery model, while it has proven to be able to provide the PPDR users with the levels of control and high availability that they require, has resulted in a niche market with far less innovation and higher price points for communications equipment in comparison to the commercial wireless communications domain. It is worth noting that the ...