Private mobile radio networks
Private mobile radio networks, also known as professional mobile radio (PMR) are mobile systems that serve a closed group of users and utilize the licensed spectrum. PMR was developed for business users who have to maintain connections at relatively short distances with a centralized base station, also called the dispatcher. A typical example is a taxi company. PMR is often also used by ambulance services. PMR networks consist of one or more base stations and several mobile terminals. Ever since their early concepts PMR systems have developed into trunked systems, with TETRA serving as a typical example. Trunking is a technique in which all resources of a communications network are shared. Usually a communication channel is assigned for the duration of the call, and is then automatically released, so another user can utilize it. It also allows interconnection of several base stations, providing coverage to a larger area than a single one would. PMR systems in general provide capabilities to closed user groups, group call, and push-to-talk, with call duration settings that are generally shorter than for the cellular systems. Numerous PMR systems support direct mode operations (DMO) in which devices can communicate directly with one another when they are beyond base station coverage. PMR systems use VHF and UHF bands.
Private mobile radio networks also include railway applications over their private network, e.g. GSM-R and RMR.
In private mobile radio networks it is permitted to use the frequencies specified in the General Act on radio frequency utilisation plan, which were awarded for PMR, GSM-R and RMR applications. The Agency launches the procedure of awarding radio frequencies after receiving an application, then issues a decision on allocating radio frequencies (DARF), which licenses the use on a particular frequency channel, and specifies the modulation, area of application, and minimum requirements regarding technical parameters.
Applications are available here.
Public mobile and hybrid radio networks
These are mobile communications networks that operate in the licensed part of the spectrum, and their use is defined by paragraphs 2 and 3 of Article 33 of the Electronic Communications Act:
- for mobile communications, where the efficient use of a certain radio frequency can only be ensured by limiting the number of issued decisions on awarding radio frequencies (paragraph 2 of Article 33) and
- for mobile communications for providing public communication services to end users (paragraph 3 of Article 33).
Public networks are mobile systems for which terminal devices are available on the open market, but can only be used in the system with a concluded subscriber agreement or an operator's approval. These systems include GSM, UMTS, LTE, 5G, MMDS, BWA and MWS.
A dedicated network means a closed network providing electronic communications services or M2M connections that does not share the resources or offer services to end users. It can be built by an operator of a private or a public network. These include for example public communication networks (e.g. mobile such as GSM, UMTS, LTE and 5G, and broadband access systems, MMDS, etc.), and M2M radio connections with electronic communications services based on mobile technology using licensed part of the spectrum for dedicated networks.
It is permitted to use the frequencies specified in the General act on radio frequency utilisation plan, and awarded for TRA-ECS, MFCN, terrestrial mobile PAMR (and in the Notes column: IMT or broadband systems), digital cellular systems, MWS, MMDS, BWA or M2M applications.
4G is the fourth generation of mobile communications and a continuation of 2G technology, which provides voice call and text messaging services, and 3G technology, which introduced effective internet access over a mobile telephone. 4G services provide much faster web browsing on mobile phones, tablets and notebook computers – transfer speeds are close to fixed broadband access speeds.
5G is the fifth generation of mobile communications and an upgrade of previous generations:
- 1G (NMT): the analogue technology which brought mobility to voice calls,
- 2G (GSM): the digital technology, suitable for making voice calls and text messaging,
- 3G (UMTS): the technology that provides a more effective internet access over a mobile telephone and
- 4G (LTE): the technology that provides higher transfer speeds and has a priority for All-IP communications.
5G (NR), or by the ITU definition also IMT-2020, is the new generation of mobile communications, which in accordance with the ITU requirements from the ITU Report M.2410 provides 3 core user cases on the radio segment:
- eMBB (extreme MBB/capacity) – support for extreme data transfer speeds for extreme data loads (top DL transfer speeds of 20 Gbps and a target user experience of 100 Mbps, with top UL transfer speeds of 10 Gbps and 50 Mbps), and latency at the user level of no more than 4 ms,
- mMTC (massive MTC/extended coverage) support for mass communications (minimum requirements of 1 million devices/m2) and
- URLLC (ultra-reliable and low-latency communications) – support for ultra-reliable and fast communication with latency at the user level of no more than 1 ms.
It also gives requirements for spectrum and energy efficiency, reliability, minimum spectrum efficiency (in bps/Hz) when used at higher speeds (e.g. vehicles travelling up to 120 km/h, bullet trains from 120 to 500 km/h).
The priority visions of the 5G technological development are:
- Extremely efficient mobile network that supports improved mobile network characteristics for lower investment costs. Addressing the operators' needs to service the growing demand for transfer speeds at about the same costs.
- Extremely fast mobile network that includes the next generation of densely deployed micro base station with high transfer speeds. Frequencies below the 700 MHz and above 4 GHz will be utilized, along with Dynamic Spectrum Access.
- Combining the fibre optics with the wireless network at millimetre wavelength (20-60 GHz) to support internet access transfer speed up to 10 Gbps, and along with mobile access also provide nomad services, such as Wi-Fi.
- 5G networks should cover the needs of some vertical sectors, especially the automotive industry, transportation, medical, energy, manufacture, and media and entertainment.
In 2014 the GSMA set the 8 most important criteria that 5G technology aims to meet:
- 1-10 Gbps connections at end points in the field (not as a theoretical maximum),
- 1 millisecond latency between two end points (end-to-end latency),
- 1000-times the bandwidth per unit of space,
- 10-100-times the number of connected devices,
- (Detected) 99.999% accessibility,
- (Detected) 100% coverage,
- 90% lower network energy consumption and
- up to 10-year-battery-powered operation for devices in M2M networks.
5G networks will include a lot more intelligence and will be able to coordinate smaller cells both by size and coverage. Alongside the existing macro cells they will also include smaller cells that will provide high transfer speed density at an individual area. The utilization of new frequencies and new advanced antennae assumes up to a thousand-fold increase in speeds, compared to current mobile technologies. The use of edge intelligence technologies is also planned, giving cells autonomous decision-making on routing data traffic and ensuring low latency.
Alongside ensuring sufficient transfer speeds for upcoming video services, improved user experience and the support for growing use of wireless technologies, the development of 5G is mostly focused on improving support for M2M communication, also known as the Internet of Things (IoT). This should accelerate the development of smart technologies, applications and services. It is progressing towards cheaper, energy-efficient devices with integrated eSIM cards. These devices will be the engine of industry automation (so-called Industry 4.0), automated traffic, smart cities, the smart home, smart buildings, and similar. 5G technology should bring great advances in the implementation of autonomous vehicles and next generation transportation.
It is expected that 5G networks will accelerate the implementation of new commercial services, opening new revenue streams for operators. Devices we cannot imagine are expected to be developed, additionally accelerating the development of the electronic industry and related providers of apps and content. The need for using new network approaches introduced by the concepts of Network Functions Virtualization (NFV) and Software Defined Networks (SDN) will be further emphasized. The implementation of 5G technologies will also increase the need for developing new antennae and antennae systems (Multiple-User Multiple Input Multiple Output – MU MIMO), and methods for coding wireless transfer (Sparse Code Multiple Access – SCMA).
The commercial launch of 5G networks will also demand mastering of some other non-technological challenges, such as:
- Awarding new frequency bands: existing parts of the spectrum are over overcrowded, so new frequency bands will be required for the next generation of mobile network. This is currently one of the priorities of ITU working groups and political decisions in the European Commission, and the European Parliament.
- Cost control: until the technology is fully developed, nobody knows exactly how much it will cost. However, if new services accelerate the transition to new technology, and terminal devices settle at acceptable prices, we can expect that this will result in a state where users' needs are met and major investments from operators and service providers are covered.
MMDS (Multimedia Multipoint Distribution System) Multimedia multipoint distribution systems are broadband connections (some 100 MHz) between the central station’s carrier and its terminal stations and end users, aimed at providing multi-program television, voice, and data services. It is allowed to use radio frequencies specified in the General act on radio frequency utilisation plan which are reserved for fixed point-multipoint applications, MWS, and MMDS.
MWS (Multimedia Wireless System) multimedia wireless systems are broadband connections between the central station’s carrier and its terminal stations and end users, which are used for the wireless transmission of multimedia content to end users.
BWA (Broadband Wireless Access systems) are broadband wireless access systems, mostly meant for fixed FWA, nomad NWA, and mobile MWA wireless access systems for access to end users (last mile connections). They can also be used for fixed wireless P-P systems or P-MP for linking the infrastructure of a BWA carrier, however only in rural areas, where it is, despite using a part of the radio spectrum for infrastructure connections, possible to assure appropriate levels of service quality to all interested users.