Technology
The technology for VIRVE has been developed by Nokia and the construction was overseen by the Ministry of Internal Affairs. The Terrestrial Trunked Radio-based system uses the frequency band of 380–400 megahertz, which is lower than GSM. Due to the lower frequency band fewer base stations are needed. Unlike its analog counterparts, Digital VIRVE is encrypted though it suffers the same backdoor security issue all Tetra have in common, and it has unified all previous authority networks into one network. The network makes it possible to transfer pictures and the same digital services as the GSM network. Furthermore, the network has a group call service that enables fast and efficient communication in a group of users. The expected number of clients in the network is 50,000. In July 2009 the number was 31,000. The power of the base stations is set to 25 watts, in vehicular devices it is 10 watts and in portable devices 0.5–3 watts.
The network is separated into groups that can be modified in according to the needs of the operation at hand. The network is used by security officials: the police, rescue services, customs, border guard, social- and health department and the Finnish Defence Forces. Authorities can also allow access to the network for other personnel separately for a limited amount of time, under contract or limited to certain events. VIRVE is controlled and upheld by Suomen Erillisverkot Oy (State Security Networks Ltd.), which is owned by the State of Finland in whole.
The current TETRA-based network will be replaced by 4G/5G-based network starting in 2022 and current TETRA-based network is estimated to be available until 2025. Procurement process has started in spring 2019.
The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile devices such as mobile phones and tablets. GSM is also a trade mark owned by the GSM Association. GSM may also refer to the Full Rate voice codec.
General Packet Radio Service (GPRS), also called 2.5G, is a packet oriented mobile data standard on the 2G cellular communication network's global system for mobile communications (GSM). GPRS was established by European Telecommunications Standards Institute (ETSI) in response to the earlier CDPD and i-mode packet-switched cellular technologies. It is now maintained by the 3rd Generation Partnership Project (3GPP).
The Universal Mobile Telecommunications System (UMTS) is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP, UMTS is a component of the International Telecommunication Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code-division multiple access (W-CDMA) radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators.
Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter. Radio waves with frequencies above the UHF band fall into the super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF or lower bands. UHF radio waves propagate mainly by line of sight; they are blocked by hills and large buildings although the transmission through building walls is strong enough for indoor reception. They are used for television broadcasting, cell phones, satellite communication including GPS, personal radio services including Wi-Fi and Bluetooth, walkie-talkies, cordless phones, satellite phones, and numerous other applications.
Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services.
Terrestrial Trunked Radio, a European standard for a trunked radio system, is a professional mobile radio and two-way transceiver specification. TETRA was specifically designed for use by government agencies, emergency services, for public safety networks, rail transport staff for train radios, transport services and the military. TETRA is the European version of trunked radio, similar to Project 25.
Base station is – according to the International Telecommunication Union's (ITU) Radio Regulations (RR) – a "land station in the land mobile service."
Professional mobile radio are person-to-person two-way radio voice communications systems which use portable, mobile, base station, and dispatch console radios. PMR systems are based on such standards as MPT-1327, TETRA, APCO 25, and DMR which are designed for dedicated use by specific organizations, or standards such as NXDN intended for general commercial use. These systems are used by police, fire, ambulance, and emergency services, and by commercial firms such as taxis and delivery services. Most systems are half-duplex, in which multiple radios share a common radio channel, and only one can transmit at a time. Transceivers are normally in receive mode, the user presses a push-to-talk button on his microphone when he wants to talk, which turns on his transmitter and turns off his receiver. They use channels in the VHF and UHF bands, giving them a limited range, usually 3 to 20 miles depending on terrain. Output power is typically limited to 4 watts. Repeaters installed on tall buildings, hills or mountain peaks are used to increase the range of systems.
A cellular network or mobile network is a telecommunications network where the link to and from end nodes is wireless and the network is distributed over land areas called cells, each served by at least one fixed-location transceiver. These base stations provide the cell with the network coverage which can be used for transmission of voice, data, and other types of content. A cell typically uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed service quality within each cell.
A two-way radio is a radio transceiver, which is used for bidirectional person-to-person voice communication with other users with similar radios, in contrast to a broadcast receiver, which only receives transmissions.
Sepura Limited is a British telecommunications equipment provider that develops and supplies radio terminals, accessories and software applications for business and mission critical communications. The company specialises in Terrestrial Trunked Radio (TETRA) and LTE (telecommunication) technology.
Project 25 is a suite of standards for interoperable digital two-way radio products. P25 was developed by public safety professionals in North America and has gained acceptance for public safety, security, public service, and commercial applications worldwide. P25 radios are a direct replacement for analog UHF radios, but add the ability to transfer data as well as voice, allowing for more natural implementations of encryption and text messaging. P25 radios are commonly implemented by dispatch organizations, such as police, fire, ambulance and emergency rescue service, using vehicle-mounted radios combined with repeaters and handheld walkie-talkie use.
Mobile telephony is the provision of telephone services to mobile phones rather than fixed-location phones. Telephony is supposed to specifically point to a voice-only service or connection, though sometimes the line may blur.
GSM-R, Global System for Mobile Communications – Railway or GSM-Railway is an international wireless communications standard for railway communication and applications.
A mobile phone operator, wireless provider, or carrier is a mobile telecommunications company that provides wireless Internet GSM services for mobile device users. The operator gives a SIM card to the customer who inserts it into the mobile device to gain access to the service.
Channel 37 is an intentionally unused ultra-high frequency (UHF) television broadcasting channel by countries in most of ITU region 2 such as the United States, Canada, Mexico and Brazil. The frequency range allocated to this channel is important for radio astronomy, so all broadcasting is prohibited within a window of frequencies centred typically on 611 MHz. Similar reservations exist in portions of the Eurasian and Asian regions, although the channel numbering varies.
TETRAPOL (Terrestrial Trunked Radio POLice) is a digital professional mobile radio standard, as defined by the Tetrapol Publicly Available Specification (PAS), in use by professional user groups, such as public safety, military, industry and transportation organizations throughout the world. Airbus Defence and Space is the main supplier of this technology.
The Norwegian Public Safety Network is a public safety network system based on Terrestrial Trunked Radio (TETRA). Nødnett is implemented by the Directorate for Emergency Communication. The network is primarily used for internal and interdisciplinary communication by the police, fire departments and health services. Nødnett is also used by several organisations participating in rescue and emergency work. Planning of the network started in 1995 and in 2006 the contract to build it was awarded to Nokia Siemens Networks. As Nokia Siemens Networks was unable to complete the contract, it was passed on to Motorola Solutions in 2012. The critical infrastructure of Nødnett was finished and was operational in all districts of mainland Norway by December 1, 2015.
Cellular frequencies are the sets of frequency ranges within the ultra high frequency band that have been assigned for cellular-compatible mobile devices, such as mobile phones, to connect to cellular networks. Most mobile networks worldwide use portions of the radio frequency spectrum, allocated to the mobile service, for the transmission and reception of their signals. The particular bands may also be shared with other radiocommunication services, e.g. broadcasting service, and fixed service operation.
The R-187 "Azart" is a Russian tactical and public safety handheld radio developed and produced by NPO Angstrem for the Russian Ministry of Defense. It is a component of the Ratnik infantry combat system.
