The Italian radar
We can not speak Italian without the radar to make a brief introduction to the history of the same radar because the ups and downs that led to its creation and use in the field of war have traveled different paths in different countries even if they all have in common a start. The problem of detecting the echoes produced by electromagnetic waves is placed in
since 1901-1902, Kennelly, Heavsyde Marconi and found that these waves were reflected by ionosphere. The same problem of reflection of waves was later developed in another field Hulsmeyer by German engineer who in 1904 obtained a patent for an apparatus which he called "telemobiloscopio" who was able to receive the echo of the electromagnetic waves reflected from metal objects away some hundred meters. The studies and experiments continued at a similar time in the United States, England, Germany, France, Japan and Italy but in each laboratory research in the field of propagation and reflection were without depth that scholars have yet made explicit the ultimate goal of their research, which is what was later called "Radar" (radio detection and ranging).
Moreover, while the world was begun detailed studies of radio by Guglielmo Marconi and the more achievements for long distance communications, with the use of high power transmitters in order to "myriametre", ie a low frequency, Marconi in Italy promoted and became a supporter of links to "wave", ie high frequency, making use of antenna systems "beam" and beginning, starting in 1916, a series of experiments that exploited the directionality of systems "beam". This led him to see their use in the marine field for the presence of metal objects at great distances. In a report remained He made famous by June 20, 1922 to the 'American Institute of Electrical Engineers and to the' Institute of Radio Engineers, Marconi made concrete predictions about the possibility of using radio waves to create a backup system for shipping, based on possibility of electric waves to be reflected by conducting bodies. Among other things, said
"... In my experience I have found some effects of reflection and revelation of these waves by metallic objects at a distance of miles. I think it should be possible to design equipment with which a ship could radiate or project a divergent beam of these rays in any desired direction, which rays, encountering an object metallic object such as another ship or ship, would be reflected from the transmitter to a receiver shielded room [located] on the sending ship, and then immediately reveal the presence and direction of the other ship in fog or even by bad weather. "
There ' is doubtful, therefore, that already in the mind of Marconi Radar in 1922 the idea was unmistakably clear, based not only on theoretical speculations but also on experimental findings. Only since 1924 the British physicists Appleton and Barnett and thereafter American physicists Breit and Stuve, with completely different procedures, began experiments to record the echo reflected from the ionospheric layers, pouring in the range radio technology Detection of acoustic echo already developed in the range: the British, following a scheme based on frequency modulation, the Americans, following a scheme based on pulse method. These can be considered the starting point for studies that led to the creation of equipment for the determination, the true ancestors of Radar.
From these starting points of scientific research paths diverged in different laboratories according to different principles. All, however, were united by the fact that as was outlined more clearly the possibility of military results, more and more increased the confidence on the progress achieved. Some governments and some states were much more far-sighted nell'intravedere the enormous importance, particularly in the naval and air, the distant location of obstacles (potential "targets") by means of radio waves. That vision led to the difference in allocation of economic and scientific resources for the study of this issue so important. The General Staff English, for example, strongly supports studies initiated by prof. Watson Watt (later Sir) in 1935 that led to the construction of experimental apparatus, gradually improved, meant that in the early '40s England possessed a network of coastal radar for spotting aircraft and radar ship to the discovery that both naval and air for direction of the shot.
In Italy, however, with regard to the development of research, things proceeded in a very, very different. In 1933 Marconi performed in the presence of Italian military authorities, expertise on changes that occurred in the reception of signals due to the passage of cars in the vicinity of the beam of a bridge that emitted radio waves of 90 cm installed between Rome and Castel Gandolfo. These experiences are also interested in the young engineer Ugo Tiberio, then second lieutenant in military service at the Military Institute of Superior Transmissions (ISMT) in Rome.
In subsequent years, other series of experiments led to Marconi for radio-determination up to arrive in 1935 upon presentation to the highest Italian authorities of an apparatus called "radioecometro" but still was not powerful enough to be of military interest. This presentation was, however, sufficient to trigger the imagination of journalists who came to speak of "death ray" exchanging charred as radiation apparatus made by Marconi, the remains of a sheep that had actually been roasted by shepherds Agro Roman!
to deepen the military of these experiments was set up a special interministerial Commission gave a mandate to continue the research to engineer Tiberius, then no more reserve officer, but dell'ISMT employee as engineer and teacher of radio technology. Engineer Tiberius, on his own, since 1931 he was individually interested in what he later called "Radio-Detector Rangefinders (GDR) and later simply" radio telemetry (rare), however, always follow up the experiences of Marconi when, in July 1937, these experiences were rudely interrupted by the death of the latter. In the course of his research, the now "professor" Tiberius context on the depth of the experience according to the two methods, respectively, by physicists from the British and Americans, that is the method that uses frequency modulation is to which used the technique of pulse, as the technology of the moment not favored either method because of reduced power that could be obtained with the radio components available.
For the usual budgetary constraints that have always plagued (and, alas, still continue to plague) research in Italy, the Inter-Ministerial Committee preferred to adopt the solution that seemed the most economical and Professor Tiberius had only further research following the technique frequency modulation. At the end of 1935, Tiberius presented his report which was theoretically developed and solved in all details, including calculations, the problem of determination. In this report, of course, was secret, the tracks were lost because of the war. The same professor regretted very much of this loss because it was the clear demonstration of the results of which had arrived ahead of all others in the world. Fortunately, recently, the family of Professor. Tiberius found the handwritten draft of a second report dated April 26, 1936 XIV, a few months back with a report of 1935, as detailed and complete and that indirectly refers to the previous one [image at the beginning: the first fragment of the page].
Once again we see how they had been identified in due time the possibilities offered by this particular use of the spectrum but, unfortunately, would not raise in those who had to make decisions, the great interest that they deserve
The proposal of Professor Tiberius was formally approved by the Committee and as the problem was considered the responsibility of the Navy, that the three armed forces was one that showed most interest in the implementation of the radio telemetry and was the most organized in terms of technical research and development in the field of radio-electrical engineering (the term "e" at the time did not yet exist), was established in 1936 a working group directed by professor at Tiberius the Royal Institute of Electrical and Communications Marina (RIEC), physically located in the district of the Naval Academy of Livorno (The Institute, which in the was commonly called the "Institute CE" or "Marinelettro" has now been renamed the Institute for Telecommunications and Electronics (Mariteleradar) dedicated to Professor Giancarlo Vallauri and admiral who was the first and for many years director). This group was given the task of going from the theoretical to the experimental phase.
Professor Tiberius, meanwhile, was appointed Officer of the Corps and the Naval Weapons used in the Academy as a teacher of physics and radio engineering, respectively, the normal courses and further training courses for the officers of Naval Engineers and Naval Weapons. The financial resources and personnel available for this task was difficult, However, very limited (four non-commissioned officers, some workers and an annual allocation of 20,000 pounds - about thirteen thousand Euro (twenty five million pounds) at the current, so the professor Tiberius had almost single-handedly lead the development and testing of the prototype radio telemetry already designed theoretically . Together with Professor Tiberio began working in the project also Professor Nello Carrara, another teacher of physics at the normal course of the Naval Academy. Carrara Professor since 1924, a young physicist, was part of the Institute and EC, since 1932 involved in research in the microwave; she is the creation of the term "microwave" (and "microwaves") in the scientific literature of the period. Professor Carrara in the "GDR" engaged primarily in the design and manufacture of power tubes and magnetron components, these are indispensable in order to achieve significant results. The two professors, not breaking its commitments of teachers (lectures, tutorials, lecture preparation, examination boards) did not disdain to take part directly to the pursuit and practice of manual equipment.
was born in 1936, the first RDT (Radio Detector rangefinder) EC1 continuous wave (an acronym derived from the name of the Institute EC) in 1937 which was followed by the bis-EC1 and EC2 which gave satisfactory results. In 1937 he joined the research team Captain of Naval Weapons, Alpheus Brandimarte engineer that he began to work on the experimental realization of the prototype dell'EC3 no longer modulated continuous wave frequency, but pulse. This collaboration, however, was short-lived because Brandimarte, for the entry into force of a strange fascist law on celibacy, he saw himself precluded the possibility of career in the Navy and was forced to resign. Unfortunately martyr of the Resistance and then fell to his memory was decreed MOVM
the research team went back to being composed by the combination of Tiberius-Carrara while continuing to maintain their teaching commitments! It is worthwhile to recall here the important contribution made by prof. Carrara who designed a valve, made by Italian fivre (Valve Radio Electric Factory Italian), which allowed him to reach a peak power of 10 KW and inserted into a cavity resonator at high gain (Q), also of his design, overcame the difficulty of obtaining high power at centimeter waves (70 cm).
Even so, given the slowness with which the industry realized what was designed by the researchers and given the small quantities produced, they had to find other ways to get the peak power required for a good range of radio telemetry. Since the market was still free, you had to buy in the U.S., and exactly at the RCA the power tubes needed to meet the needs of researchers. Experimental tests of two prototypes, always conducted in the Institute by the end of 1939 CE, respectively RDT3, coastal, and EC3, naval, (since December 1940 as amended in EC3-bis), suggesting the possibility of achieving significant results . Evidence-bis dell'EC3 suffered slowdowns and delays for both the need for further adjustments, both for the interest of not too high military hierarchy but, to tell the truth, the Navy was stirring some interest in what in the subsequent decades will be called "Electronic Warfare". However, at the end of February 1941 has been shown dell'EC3-bis had not yet been done!
To highlight the difficulties that struggling small team seems appropriate to set out verbatim what the professor wrote in 1951. Tiberius recalling those pioneering times, "in 1938, given the difficulty of finding other researchers to devote to studies on the radar, the Navy Department decided to try to bind an important radio industry in Milan, which, however, was reduced to asking the Navy technicians needed since it already committed all of its employees: the Navy could not fulfill the request, and then even this attempt was unsuccessful "(Tiberius - On the development of knowledge Italian radar during the war - Review Seas - April 1951). In other words: the dog that eats its own tail!
It was only after the heavy losses suffered by our Navy in the night between 28 and 29 March 1941 at Cape Matapan, when the doubts became certainty that the British Navy possessed equipment for radio-determination, which was re-evaluated the importance of having in Italy of similar equipment. Once again came under pressure, the Institute and EC, therefore, teachers Tiberius and Carrara. They were hastily restored prototypes thus far and from these sprang two devices, respectively baptized "Coot" and "Owl" which differed mainly for the working frequency band and they did of the "Coot" a prototype for coastal surveillance and "Owl" a prototype for naval use. The
"Coot" was operating in a band between 150 and 300 Mhz (2-1 meters) while the "Owl" was operating in the band between 400 and 750 MHz (75 - 40 cm). The services provided by these two prototypes were really excellent. Please note that during the experimental tests of the "Coot" conducted on the terrace of the Institute of CIs in May 1943 was seen at 200 km training of U.S. aircraft that was coming.
( source)
Ugo Tiberio
inventor of radio telemetry "
Hugh Tiberius was born in Campobasso August 19, 1904.
in Naples in 1927 graduated in civil engineering, he majored in electrical engineering in 1932 in Rome. Called to arms
first appointment as an officer in the Army, passed in 1936 in the Navy, which won the competition for appointment as a reserve officer in the body of Naval Weapons. Intended for RIEC there finished his studies already undertaken on the radar, which he named radio telemetry.
was a university professor in Livorno, Cagliari, Naples and Pisa, where taught until 1979, the year of retirement for age limit.
died May 17, 1980 in Livorno.
( source)
let us just one thing: we had the radar. I do not call it that, but we had.
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