PMR - Private Mobile Radio
PMR (Private Mobile Radio or Professional Mobile Radio) is used predominantly by business users who wish to have dedicated and reliable voice and data communications at their disposal. PMR systems are generally owned and operated by the same organisation that the users belong to, however there are also PAMR (Public Access Mobile Radio) systems where an organisation operating the system provides PMR services to users belonging to a number of different organisations.
PMR systems use dedicated radio frequencies which are licensed by the regulator which manages the radio spectrum for a country. This ensures that the radio frequencies are available for the sole use of the PMR system and that other radio in the same frequency band doesn’t interfere with the operation of the system.
PMR systems consist of two key elements – infrastructure and terminals. Infrastructure is provided by one or more radio base stations or repeaters which can be deployed on a single site or dispersed over a large geographical area to provide coverage over a wide area. Terminals usually refer to the hand portables carried by users or the mobile radios commonly installed into vehicles but can also include applications such as voice and data dispatching.
Some of the key attributes of PMR systems are;
- Coverage – a PMR system is designed to provide coverage for the entire operational environment so that radio signals are transmitted to all of the locations when communications are required by the customer. In addition to outside locations, this may include in building coverage and underground locations such as tunnels where Simoco has significant experience of designing antenna solutions in confined spaces.
- Group Communications – business operations quite often rely on group calls to facilitate efficient operational communications. A simple example of this can be provided by security staff in large sporting stadiums where a member of staff can call for assistance from a number of colleagues by making a group call using a single button press.
- Reliability and Resilience – PMR systems are often the first choice for communications where safety is paramount. This is why the public safety services of police, fire and ambulance use PMR as their primary means of voice communications. Due to the requirements of these organisations that the systems they use are ultimately reliable, PMR systems are often designed to continue to provide service in the event of equipment or power failure through the use of intelligent fallback mechanisms and power backup using batteries and/or generators.
- Performance – PMR systems use efficient signalling protocols to ensure very quick call establishment times. Often, user organisations have requirements to be able to start speaking almost as soon as they decide to make a call and cannot wait for someone to answer a phone. For this reason, PMR systems provide a large range of call types from open channel calls where the user can quickly press and talk to emergency calls which will always get through no matter how busy the system is.
- Contention – the size of a PMR system can be designed to deliver the quality of service required by the users. For non-essential communications it might be acceptable for users to queue or wait until resources are available and can therefore use a small system but for higher end users the system can be designed with a large amount of capacity to ensure that calls are always completed regardless of how busy the system becomes.
- Security – privacy of communications can be very important to organisations to ensure that their conversations do remain private. PMR systems are able to offer varying levels of security from basic voice scrambling right up to complex military grade encryption algorithms depending upon the needs of the encryption.
Simoco have over 70 years of expertise in the PMR industry as a manufacturer of infrastructure and terminals and also as a full turnkey system integrator and maintainer. We have a full range of solutions for professional users including the latest digital radio technologies including DMR, P25 and TETRA and we continue to push the boundaries through our work within the industry in the ongoing development of open standards.