Fundamentals of Radar Technology
It was not the first time, and it won't be the last time that technology has received an enormous boost through military use. One can see by the development of radar technology, how through immense investments,
research and development can progress in a relatively short time, so much so, that they can even influence wartime decisions.
Even before the first world war, radar technology had been sufficiently developed that ships could locate each other in bad weather. Due to the size of some ships nowadays, the manoeuvrability has become even
worse. Supertankers e.g., often need as much as 15 minutes warning, otherwise a collision is inevitable. At that time, obviously, nobody recocnised the value of radar over such short distances.
The immense development thrust from 1935 to 1945, (shortly before and during the second world war) was triggered by the expected ability of radar equipment, to recognise attacking hostile vehicles (air, land or sea),
even at a distance of 100 kms., to determine their position and to initiate suitable countermeasures.
With the initial passive radio-wave measuring technology, an area was protected by erecting transmitter (2)- and receiver (3)-aerials at great distances to each other. Strong energy sources sent out concentrated ultra-
short wave radio signals which could be picked up and shown on the (at that time still round) oscilloscope (4) screens. (see above) In its simplest form, the
received signal was directed to the vertical deflection plate, while the electron beam was, time dependently, horizontally deflected. The time is co-ordinated to the possible reflected waves. In the above example, a
reflection occurs at a distance of approx. 35 km. By analysing similar signals from various points, the positions of aircraft/shipping can be determined and defensive forces can be accurately deployed.
The health dangers imposed on the evaluating staff were only later discovered. Thus, ever greater measurung distances led to ever increasing energy sources. In this case, the tubes used at that time, produced not
only radio-waves but also X-ray waves. If one observes how meticulous and carefully examinations are carried out nowadays, one can imagine the results of what constant, even if less intense, exposure to radiation
would be. These then, are the disadvantages of a technology progressing rapidly in a very short time.