29 Jun 2016

The future of PMR

While no-one can accurately predict what communications will look like in the future, Chris Lorek explores the trends that will most likely influence two-way radio’s destiny, with a focus on private mobile radio

It’s only recently that we’ve started to see software-defined radio (SDR) in commercial use, primarily on HF from companies such as Codan and Barrett, although it has been in amateur radio and military radio use for some time. The Wireless Innovation Forum was established in 1996 and is a non-profit international industry association dedicated to creating a revolution in wireless communications based on reconfigurable radio. Now, 20 years later, we’re starting to reap the benefits of SDR technology in commercial VHF/UHF two- way radio, as digital technology becomes more widely available at low cost.

An average SDR currently uses little analogue circuitry, typically a wideband transmitter power amplifier and front-end amplification and selectivity for VHF/UHF receive. Recently a transceiver design based entirely on digital technology, the Pizzicato, was revealed.

SDRs are flexible enough to allow wideband operation along with multimode transceive capability including spread spectrum. This latter mode allows several transceivers to operate in the same geographical location on the same frequency with very little interference, and is typically combined with appropriate error detection and correction techniques within the transceiver.