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30-500: The EISCAT Scientific Association exists to provide scientists with access to incoherent scatter radar facilities of the highest technical standard. The construction of EISCAT's new generation of incoherent radars: EISCAT 3D, has started in November 2022. The first stage of the new system will consist of three radar sites, functioning together, just as the old mainland system. Later, transmitter up grade and more sites will be added to

60-693: A 32 meter mechanically fully steerable parabolic dish antenna, and a 42 meter fixed parabolic antenna aligned along the direction of the local geomagnetic field. The whole radar system is controlled by computers, and the sites in Tromsø, Kiruna, Sodankylä, and Longyearbyen are interconnected via the Internet. An ionospheric heating facility, Heating, is also located in Ramfjordmoen outside Tromsø, Norway. It consists of 12 transmitters of 100 kW CW power, which can be modulated, and three antenna arrays covering

90-452: A decision as to whether a target is present. This is analogous to the use of antenna diversity in an attempt to improve links in wireless communications. This is useful where multipath or shadowing effects might otherwise lead to the potential for poor detection performance if only a single radar is used. One notable area of interest is in sea clutter, and how diversity in reflectivity and Doppler shift might prove beneficial for detection in

120-433: A differing bistatic angle and target radar cross section . The following characteristics are unique to the multistatic arrangement, where multiple transmitter-receiver pairs are present: Increased coverage in multistatic radar may be obtained via the spreading of the radar geometry throughout the surveillance area - such that targets might be more likely to be physically closer to transmitter receiver-pairs and thus attain

150-470: A higher signal-to-noise ratio . Spatial diversity may also be beneficial when combining information from multiple transmitter-receiver pairs which have a shared coverage. By weighting and integrating individual returns (such as through likelihood ratio based detectors), detection can be optimised to place more emphasis on stronger returns obtained from certain monostatic or bistatic radar cross section values, or from favourable propagation paths, when making

180-455: A maritime environment. Many stealth vehicles are designed to reflect radar energy away from expected radar sources in order to present as small a return to a monostatic system as possible. This leads to more energy being radiated in directions that are only available to multistatic receivers. Resolution may benefit from spatial diversity, due to the availability of multiple spatially diverse down-range profiles. Conventional radar typically has

210-469: A meeting in 1973, where a board and a chairman were appointed, that the work really began. In 1974, the Council presented a report on how the organisation, operations and implementation of EISCAT's UHF system could take place, and at the end of 1975 the first six member states agreed to start the work towards the construction of EISCAT. The member countries are now Sweden, Norway, Finland, Japan, China and

240-593: A much poorer cross-range resolution compared to down-range resolution, thus there is potential for gains through the intersection of constant bistatic range ellipses. This involves a process of associating individual target detections to form a joint detection. Due to the un-cooperative nature of the targets, there is potential, if several targets are present, for ambiguities or "ghost targets" to be formed. These can be reduced through an increase in information (e.g. use of Doppler information, increase in down-range resolution or addition of further spatially diverse radars to

270-428: A position at National Physical Laboratory at Slough , near London, working closely with Sir Edward Appleton . Together they performed basic studies of radio wave propagation by reflection from these layers. This cooperation persisted over a few decades, during which Beynon as representative of Sir Edward held senior offices in national and international committees, and took active part in the preparation and conduct of

300-399: A single site. To deduce the range or velocity of a target relative to a multistatic system, knowledge of the spatial location of transmitters and receivers is required. A shared time and frequency standard also must be maintained if the receiver has no direct line of sight of the transmitter. As in bistatic radar, without this knowledge there would be inaccuracy in the information reported by

330-563: Is involved in data fusion, such as attempts to increase resolution. Several passive radar systems make use of multiple spatially diverse transmitters and hence may be considered to operate multistatically. Granville Beynon Sir William John Granville Beynon , CBE , FRS (24 May 1914 in Dunvant – 11 March 1996 in Aberystwyth ) was a Welsh physicist . He co-operated with Sir Edward Victor Appleton , who had detected

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360-415: Is the added requirement for some level of data fusion to take place between component parts. The spatial diversity afforded by multistatic systems allows different aspects of a target to be viewed simultaneously. The potential for information gain can give rise to a number of advantages over conventional systems. Multistatic radar is often referred to as "multisite" or "netted" radar and is comparable with

390-793: The International Geophysical Year 1957/8, which was a break-through in international cooperation in geophysics. He became thereafter one of the leading personalities in international scientific cooperation, in particular in the International Union of Radio Science (URSI). His perseverance saved the European Radar project EISCAT , by which progress was reached in understanding particular atmospheric phenomena at high latitudes. In 1942 Beynon married Megan James. The couple had two sons and one daughter. From 1946 Beynon carried out studies in physics at

420-537: The Scandinavian Arctic Circle . The core in the tri-static system, is located at Ramfjordmoen, outside Tromsø, Norway with a 32 meter mechanically fully steerable parabolic dish used for transmission and reception in the UHF -band. Operating in the 930 MHz band with a transmitter peak power 2.0 MW, 12.5% duty cycle and 1 μs – 10 ms pulse length with frequency and phase modulation capability. And

450-457: The University of Swansea . In 1958 Beynon started teaching at the University of Aberystwyth , where he later became full professor and remained until 1991. For a long time he was chairman of the "Schools Council Committee for Wales". From 1972 to 1975 he was president of the International Union of Radio Science , and of EISCAT, of the "Year of the quiet Sun". In 1973 he became a Fellow of

480-503: The VHF radar that operates in the 224 MHz band with transmitter peak power 3 MW, 12.5% duty cycle and 1 μs – 2 ms pulse length with frequency and phase modulation capability. The antenna, used for transmission and reception, is a parabolic cylinder antenna consisting of 4 quarters, constituting a total aperture of 120 m x 40 m. This antenna is mechanically steerable in the meridional plane (-30° to 60° zenith angle), and electronically steerable in

510-542: The Advisory Scientific Committee (SAC), assist the Council in its work. 69°35′10.67″N 19°13′28.62″E  /  69.5862972°N 19.2246167°E  / 69.5862972; 19.2246167 Multistatic radar A multistatic radar system contains multiple spatially diverse monostatic radar or bistatic radar components with a shared area of coverage. An important distinction of systems based on these individual radar geometries

540-571: The United Kingdom. The members have changed somewhat: Germany is no longer a full member, France was a member from the start of the organization in 1975 until 2005, while Japan and China were added later (1996 and 2007 respectively). EISCAT is governed by The EISCAT Council , which consists of representatives from research institutions in the various member countries. Two committees, the Administrative and Financial Committee (AFC) and

570-513: The arctic circle and near the north pole, offers unique capabilities in auroral research. Svalbard’s unique climate with polar night from November until February, make the season for observing the northern lights long. The EISCAT Svalbard Radar (ESR) also operates the UHF-band, at 500 MHz with a transmitter peak power of 1000 kW, 25 % duty cycle and 1 μs – 2 ms pulse length with frequency and phase modulation capability. There are two antennas,

600-570: The areas where EISCAT 3D will be able to offer much more flexible and meticulous research data. The use of EISCAT 3D is solely civil. The new system should be up and running 2023/2024. This also means that the old mainland system will be dismantled. The mainland system consisted of three parabolic dish research radar antennas, designed as a tristatic radar, that is, three facilities that work together. The radar antennas are located in Tromsø , Norway; Sodankylä , Finland and Kiruna , Sweden, north of

630-540: The frequency range 3.85 MHz to 8 MHz. EISCAT was founded in December 1975, as an association of research councils in six member countries. But the plans to establish a research facility focusing on incoherent scatter technology in the Northern Lights zone, started as early as 1969. Many meetings with interested researchers were held in the early 70s, but it was not until Professor Sir Granville Beynon organized

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660-568: The idea of macrodiversity in communications. A further subset of multistatic radar with roots in communications is that of MIMO radar . Since multistatic radar may contain both monostatic and bistatic components, the advantages and disadvantages of each radar arrangement will also apply to multistatic systems. A system with N {\displaystyle N} transmitters and M {\displaystyle M} receivers will contain N M {\displaystyle NM} of these component pairs, each of which may involve

690-640: The longitudinal direction (±12° off-boresight). The receiving antennas in Sodankylä, Finland and Kiruna, Sweden, is fully steerable 32 meter parabolic dish antennas. The receivers include multiple channels the UHF radar and the VHF radars. The data are pre-processed in signal processors, displayed and analysed in real-time and can be recorded to mass storage media. The location in Longyearbyen , Svalbard , high above

720-700: The main site. On top of the antenna units the dipole antennas are mounted. The Skibotn facility will have 10 000 of these small antennas. The Skibotn facility will act both as a transceiver and receiver of the EISCAT 3D system. Two receiver sites are located in Karesuvando , Finland and Kaiseniemi, Sweden. The facilities will consist of 54 and 55 antenna units with approximately 5 000 dipole antennas. Space debris tracking, tracking of meteorites , research on GPS and radio traffic, space weather , aurora research, climate research and near-Earth space are some of

750-435: The multistatic system). Target features such as variation in the radar cross section or jet engine modulation may be observed by transmitter-receiver pairs within a multistatic system. The gain in information through observation of different aspects of a target may improve classification of the target. Most existing air defence systems utilize a series of networked monostatic radars, without making use of bistatic pairs within

780-442: The radar. For systems exploiting data fusion before detection, there is a need for accurate time and or phase synchronisation of the different receivers. For plot level fusion, time tagging using a standard GPS clock (or similar) is more than sufficient. The increase in information from the multiple monostatic or bistatic pairs in the multistatic system must be combined for benefits to be realised. This fusion process may range from

810-471: The simple case of selecting plots from the receiver closest to a target (ignoring others), increasing in complexity to effectively beamforming through radio signal fusion. Dependent on this, a wide communications bandwidth may be required to pass the relevant data to a point where it can be fused. Data fusion will always mean an increase in processing compared to a single radar. However it may be particularly computationally expensive if significant processing

840-514: The system. Increased survivability and "graceful degradation" may result from the spatially distributed nature of multistatic radar. A fault in either transmitter or receiver for a monostatic or bistatic system will lead to a complete loss of radar functionality. From a tactical point of view, a single large transmitter will be easier to locate and destroy compared to several distributed transmitters. Likewise, it may be increasingly difficult to successfully focus jamming on multiple receivers compared to

870-505: The system.   Instead of parabolic dishes, as the old system, EISCAT 3D is a multistatic radar composed of three phased-array antenna fields. Many small antennas working together as one. Each field will have between 5 000 - 10 000 crossed dipole antenna mounted on top of a ground plane 70 meters in diameter. The core site of EISCAT 3D is located just outside Skibotn , Norway. The facility will have 109 hexagonal antenna units as its main antenna, and 10 antenna units spread out around

900-415: The terrestrial Ionosphere . William John Granville Beynon was born in Dunvant , near Swansea , Wales on 24 May 1914, the youngest of four children. His father, a miner, held the responsible jobs of checkweightman and chief of the local mines rescue service. Beynon was educated at Gowerton Grammar School , before matriculating to the University of Swansea , where he studied physics. In 1938 he gained

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