SA radar sector has marked a major milestone in its history

6th March 2015 By: Keith Campbell - Creamer Media Senior Deputy Editor

SA radar sector has marked a major milestone in its history

Late last year, the South African electronics industry, the Council for Scientific and Industrial Research (CSIR), the South African National Defence Force, the Air Traffic and Navigation Services and other institutions celebrated the 75th anniversary of radar in this country. On December 16, 1939, the first South African-built radar was successfully operated for the first time.

Exactly who it was who first realised that radio waves could be used to detect and track moving objects is a minor controversy in the history of technology. However, by the 1930s, parallel and completely independent research into radar was being undertaken by France, Germany, the then Soviet Union, the UK and the US.

What is indisputable is that it was the British who first recognised the full potential of radar and were the first to make practical use of it, and on a large scale, to detect aircraft, creating the world’s first integrated air defence system. This system was complete by late 1938 and gave Britain a decisive advantage in the 1940 Battle of Britain. The British also rapidly developed radars for coast defence and for use on aircraft and ships. It was from this British research and development (R&D) and deployment that South Africa’s own radar developments sprang.

Storm Born

The Second World War erupted in September 1939. Because of the obviously deteriorating international situation, on February 24, 1939, the British authorities had briefed the High Commissioners of Australia, Canada, New Zealand and South Africa in London on the UK’s radar-based air defence system and that radar could also be used to detect ships.

The four dominions were urged to send scientists, preferrably physicists, to the UK to receive detailed technical briefings on the science and technology of radar. Australia, Canada and New Zealand did so. For reasons that are unclear, South Africa did not (although the country had a nonscientific representative at the technical briefings). As a result, it had to be arranged that the New Zealand representative, Dr Ernest Marsden, had to travel home via Cape Town and Durban, so that he could brief leading South African scientist and nuclear physicist Professor Basil Schonland on radar. (During the First World War, Schonland had served in the Royal Engineers Signal Service of the British Army – now the Royal Corps of Signals – and was decorated for his contribution to communications. He had gained his PhD in nuclear physics at the world-famous Cavendish Laboratory at Cambridge University and so was already known to his British and dominion colleagues. In 1939, he was at the Bernard Price Institute [BPI] at the University of the Witwatersrand [Wits].)

On September 14, 1939, Marsden’s ship docked in Cape Town and Schonland joined it for the three-day trip to Durban, during which time he was briefed by Marsden and studied the secret documents the New Zealander was conveying. When the ship docked in Durban, the two men spent a night making glass photographic slides of key pages and diagrams from Marsden’s papers. They then went their separate ways, Schonland speeding to Johannesburg, where a special and secret radar team, including electrical engineers, was quickly set up. This was absorbed into the South African Corps of Signals on September 18.

The reason Schonland decided to design and build a radar – using the copied documents as a guide – was, he later said, simply to learn the technique of radar. Work was started at once. Because of a lack of suitable electronic components in South Africa, this first set was based on British coast defence radars (which required a peak power of about 150 kW and operated at a frequency of about 200 MHz) rather than the long-range air defence radars (peak power of some 350 kW and a frequency between 20 MHz and 30 MHz). While the basic design was British, the detailed design was South African. Team members had to search through the stocks of amateur radio suppliers in Johannesburg to find key electronic components! The metal chassis to mount these had to be specially made by a team member.

By the middle of November, all the elements of the radar had been built and tested, but not yet integrated. The elements were then combined to create a radar set. The transmitter was put in a top floor room of Wits’ Central Block, with the antenna on the roof above, while the receiver was in the BPI building with its antenna on the roof (the two elements of the radar were separated to avoid the transmitter interferring with the receiver). Communication between the two sets of operators was through the Wits telephone exchange.

An initial test was a failure. But, on December 16, 1939, following careful tuning of the set, the apparatus successfully detected a target to the north-west at a range of 10 km – believed at the time to have been the Northcliff water tower, but perhaps it was Northcliff Hill. The significant point, however, was that the radar worked; it had detected a target.

This prototype set was designated JB0 by Schonland, standing for Johannesburg Zero. By February 1940, it was able to detect aircraft at 15 km – a range that was later increased to 80 km. It was intended for training purposes only, with operational radar sets expected to be supplied from Britain. But, in Europe, the war went badly, with the Germans rapidly overrunning Denmark, Norway, the Netherlands, Belgium and France, and Italy declaring war on the allies in June.

Faced with this dire situation, Britain could no longer spare radars for South Africa. Schonland’s team was now the Special Signals Services (SSS) of the South African Army (SA Army), and would have to produce radars to defend South Africa and South African forces deployed in East Africa to confront the Italian forces there. (SSS personnel also operated all the South African radars.)

The first production unit, JB1, was successfully tested at Avoca, just north of Durban, in June and then sent to Kenya, where it was set up and operational by August 1 at the coastal town of Mambrui. From July 1940 to February 1941, the SSS engineers built and delivered a total of six radars – five JB1s and the first JB2. Five went to East Africa and one (for evaluation) to Egypt. The British were impressed by the suitability of the South African systems for erection and operation in rugged areas. With the defeat of the Italians in Ethiopia, the JB1 sets were relocated to Egypt, where they operated alongside British radars. Later, SSS personnel also manned British radars deployed in Italy.

Given that the German Navy had deployed warships and armed merchant cruisers as surface raiders against British and allied shipping, South Africa needed coast defence radars to guard its ports. A mobile radar based on the JB1, designated JB3, was developed for this role. The first was based at Signal Hill, in Cape Town, in May 1941. The second unit was sent to Durban. The JB3 was followed by the JB4 (frequency: 125 MHz). About 13 JB3 and JB4 systems were built and deployed, complemented by British systems that the UK could now provide. The home defence radars were largely operated by women. (In the UK, women had been central to the entire air defence system since early 1940, some becoming radar instructors.)

By 1945, most of the South African coast was covered by radar. The design and assembly of all the JB-series radars had been done by the SSS: South African industry had not been involved at all (probably for security reasons). SSS personnel were also attached to South African Air Force (SAAF) squadrons to maintain airborne radars and other electronic systems. At its peak, in December 1944, the SSS numbered 145 officers and 1 476 other ranks; 535 of them were women, 28 of whom were officers. With the end of the war, the SSS was disbanded and all work on radar in South Africa abruptly ended.

In the Doldrums

In March 1941, Schonland went to Britain on secondment to the British Army (becoming, in due course, a brigadier and chief scientific advisor to the 21st Army Group). In 1945, he returned to South Africa to set up the CSIR. And one of the first units of the new agency to start operating was the Telecommunications Research Laboratory (TRL), which was largely staffed by former members of the SSS. So the expertise developed during the war had a home where it could be preserved (by undertaking civilian research using technologies related to radar), if not developed.

(Schonland stepped down as president of the CSIR in 1950; in 1954, he was appointed deputy director of the UK’s Atomic Energy Research Establishment at Harwell, in Oxfordshire, becoming its director in 1958. Knighted in 1960, he retired in 1961 as director of the Research Group of the UK Atomic Energy Authority and died in the UK in 1972, aged 76. He was named South African Scientist of the Century in 1999.)

Then, in 1951, the Defence Force reactivated radar R&D by awarding two contracts to the TRL. The first was to adapt imported equipment to meet South African conditions, while the second was for the design and development of entire radar systems, again to meet local conditions. This latter contract led to the development of the JB51 radar system. A single prototype was followed by two preproduction systems (one source says there was a production model, but does not mention the prototype). The JB51 required peak power of 200 kW, operated at a frequency of 600 MHz and produced a fully coherent low-altitude and high-altitude beams with moving target indicator. But the project was cancelled in 1960 and UK radars were bought instead. Quite simply, the six-year gap in radar research in South Africa, when combined with the high priority given to radar R&D in the UK, the US and elsewhere, meant that the JB51 was not modern enough. However, the second preproduction (or sole production) system was set at up at Pienaars River, north of Pretoria, where it was used for many years for the training of SAAF fighter controllers and fighter pilots in ground controlled interception techniques.

Again, radar research came to an effective end in South Africa. However, over the following years, the SAAF and South African Navy (SAN) did acquire considerable expertise in operating and maintaining radars. The SAAF also became an expert in designing air defence system architectures (that is, integrating radars, communications, control centres, air bases and fighter squadrons and aircraft). In addition, defence acquisition and R&D agency Armscor (founded in 1948) developed expertise in testing, evaluating and acquiring radars. And South African industry became involved in maintaining overseas-sourced radars.

A Fresh Wind

In 1965, the National Institute for Defence Research (NIDR) was set up at the CSIR. The then South African government had adopted a policy of “strategic independence” in defence technology, with a focus on the development of missiles. This required foreign help and led to the joint development, with France, of a vehicle-mounted surface to air missile, known in France as the Crotale and in South Africa as the Cactus. South African engineers from the NIDR were sent to France to participate in this programme. The Crotale/Cactus system included integral surveillance and target tracking radars. As a result, when the South African engineers returned home around 1970, they had gained invaluable experience with then modern radars, specifically S-band (2 GHz to 4 GHz frequency band) pulse doppler radar (for surveillance) and Ku-band (12 GHz to 18 GHz) monopulse target tracking radar.
With this expertise, CSIR researchers undertook a number of radar R&D projects. In parallel, expertise was also developed in the then new field of solid state electronics, essential for modern computers, which are also essential for modern radars (to process signals and eliminate unwanted returns from the ground or the sea, known as clutter, and to counter jamming). Thus, there was the 1972 to 1975 Pumar X-band (8 GHz to 12 GHz frequency) pulse doppler surveillance radar project with coherent travelling wave tube (a wide bandwidth microwave amplifier). From 1975 to 1978 there was the Beta foliage penetrating radar project, an ultra high frequency, solid state coherent pulse doppler system. Technically successful, it was tactically useless and was followed by a very high frequency (VHF) successor system, which was man portable. Again, a technical success, its tactical performance was so poor (it worked at ranges of a few hundred metres, not the kilometres required) that the project was halted.

Next came the 1979 to 1983 Nimbus Ka-band (27 GHz to 40 GHz frequency) range-only radar project. (It actually operated at 35 GHz.) This was the very first South African radar which used digital signal processing. In 1983, the Nimbus was integrated with the army’s twin 35 mm Oerlikon anti-aircraft guns, for field trials that took place in 1984, resulting in the shooting down of a drone. But a range-only radar was tactically inadequate, so Nimbus was followed by the 1983 to 1989 Fynkyk millimetre wavelength monopulse tracking radar with digital signal processing. From 1990 to 1995, Fynkyk, mounted on a mobile laboratory, was subjected to extensive field tests, including against Mirage fighters. It was then used in SAAF exercises, but never put into production. In parallel to the research-orientated Fynkyk, technology was transferred to local company ESD (now Reutech) which resulted in a tracking radar, designated Catchy, which was used in various exercises with the SA Army’s air defence artillery.

Furthermore, to support radar work, during the 1980s, a national antenna range was set up at Paardefontein. This is still operational. And, in the same period, other researchers started work to develop radomes (which must be strong, light and transparent to radar) for both radars and missiles. The CSIR also undertook radar and radar-related studies, including into pulse doppler radar (started in 1980) and studies for the SAAF and SAN. Separately, in 1988, the University of Cape Town (UCT) set up a radar remote sensing group (RRSG), to develop advanced radar sensors, techniques and applications.

Meanwhile, from the mid 1970s, South African industry began to manufacture foreign radars under licence. ESD licence produced a mortar locating radar (designated Cymbeline) for the Defence Force from 1977. From 1981, it also licence-manufactured ATCR 33 S-band air surveillance radars for the SAAF. These are still in use as air traffic control radars at various SAAF bases. In 1987, the company set up a dedicated radar unit, then called ESD South. Today, it is Reutech Radar Systems (RRS). Its first programme was Project Hexagon, which the company used to develop a thorough understanding of (then) modern radar technology. Hexagon was a project of Armscor to develop a compact vehicle-mounted aircraft warning radar, operating in the L-band (1 GHz to 2 GHz frequency). The company approached Hexagon by dividing the project into different subsystems, which were developed in parallel.

Progress was neither smooth nor easy but, by the end of 1987, initial prototypes for most of the subsystems had been developed. During 1988, improved prototypes were developed and the integration of a complete radar system was started before the end of that year. In first third of 1989, the transmitter and receiver were integrated and tested. The radar detected its first aircraft – a helicopter – in May of that year, with two engineers holding the antenna! But the war in Angola ended and Hexagon (along with the vehicle that was meant to carry it) was cancelled.

Even before the end of Hexagon, the subsystems developed for it were already being applied to two other projects, Contain (which became Contain I and Contain II) and the EDR 120 short-range air surveillance radar used as the designation radar for the Catchy tracking radar. Project Contain was for a mobile medium-range surveillance radar, to be mounted in an armoured cabin carried by a 20 t truck. The result was the Kameelperd (giraffe) radar, designated ESR 220 by the company. Also operating in the L-band, the first prototype was delivered in 1992, followed by the deliveries of production units. In radar terms it is basically an up-scaled Hexagon. Continuously improved, it is now, following a major upgrade, called the Thutlwa (which also means giraffe) in Defence Force service. (The Kameelperd and Thutlwa systems have no connection with the Saab – previously Ericsson – Giraffe radar.) Another spin-off from the Hexagon technology was the ESR 360 three-dimensional (3D) tactical mobile radar, which was evaluated over a number of years in SAAF air combat manoeuvre trials. Also, from 1993 to 1999, the CSIR transferred the pulse doppler technology it had developed to RRS, to be used in the development of the RTS 6400 X-band optronic radar tracker, today in service on the SAN’s Valour-class frigates.

During the 1990s, the CSIR, UCT’s RRSG and RRS worked together to develop an airborne VHF (141 MHz) synthetic aperture radar for the SAAF. This started flight tests in 1999.

Since then, RRS has developed a range of radars. There are the five RSR 210N naval air-sea surveillance radars supplied to the Royal Norwegian Navy (one of the North Atlantic Treaty Organisation – Nato – navies) to serve primarily as helicopter control radars on the modern Fridtjof Nansen-class frigates. Then there is the RSR 900 StealthRad family of low cost, lightweight and low probability of intercept radars. Under development is the RSR 320 ground-based 3D dual-band radar.

The company has also developed a Stealth Tracking Effective Low Level Air Defence (marketed under the acronym Stellad) system, which combines a radar and command-and- control system to increase the effectiveness of shoulder-fired surface-to-air missiles. Furthermore, RRS produces air defence control software. On the civil side, the company has its Movement and Surveying Radar, used for geotechnical monitoring and surveying in openpit mines.

At the CSIR, radar and radar-related R&D continues. In 2004, it launched Awarenet, a project to integrate multiple sensors to achieve information dominance. A spin-off of this is a project, in cooperation with some Nato countries, to detect small boats in coastal and inshore waters. Meanwhile, in 2011, the UCT launched a master’s degree in radar engineering. More recently, the CSIR has moved into the realm of space-based radars and in September last year announced a deal with local company Space Commercial Services Holdings Aerospace Group to design and develop a wide-area maritime synthetic aperture radar for small satellites.

Today, as a result of all this effort and investment, South Africa has an unusually strong radar technological and industrial base for a developing country. In addition to the main players, there are companies like Peralex and Tellumat, who locally produce key radar components. Denel Dynamics is working on radar seekers for its missiles. The local players – research institutions, industry, universities, customers – are linked by the South African Radar Interest Group, set up in 2008. But there is a feeling in the sector that the country needs a long-term strategy and plan for radar, to prevent the sector from falling into the doldrums again.