Talk:History of radar

Untitled

"Pulse radar is the only way to detect the location, size, and velocity of objects"

This is not true. The velocity of an object can be measured with a CW radar.

Cleanup

I hate to randomly put a cleanup tag on a page I find, but this article really seems to need it. There's good information in it – although I think the very brief mention of the MIT RadLab should be expanded – but it's stylistically bad, and the mass of headings and subheadings seem illogical and haphazard. –Joke137 18:41, 11 Jun 2005 (UTC)

One of these can only be true: detected at ranges up to 8 mi (132 km) (in the British origins part). Can someone verify the correct distance? —Preceding unsigned comment added by 195.42.134.4 (talk) 16:06, 24 November 2009 (UTC)

Naval Research Laboratory

Engineer Bob, Are you sure about the claim that the 1930 observation by Taylor and Young was the first demo of CW interference radar? I remember reading that similar observations of aircraft reflecting signals were known in England well before the 1935 demo by Watson-Watt and Wilkins, and in fact lead to them suggesting their radar experiment. But I do not know the exact date, or whether it predates the the Taylor and Young observation. I will dig around and see if I can find the reference again. -- Op. Deo 09:51, 25 January 2006 (UTC)

• The Taylor/Young observations were made in 1922; 1930 was Hyland's detection of an aircraft. Robert M. Page credits Taylor & Young with the accidental discovery of radar in his 1979 book The Origin of Radar, which is consistent with information on the IEEE and NRL websites. Engineer Bob 10:10, 25 January 2006 (UTC)

Thanks, I carelessly misread the wrong date in the article, and jumped to quite the wrong conclusion. I am not familiar with the Page book - I will go and read it. All I can add further is that what may be regarded as the first actual use of CW radar was by Appleton and Barnett in 1924, see Appleton Nobel prize lecture, when they measured the 90 km height of the E-Layer. -- Op. Deo 12:10, 25 January 2006 (UTC)

Battle of the Beams

At the start of World War II both the United Kingdom and Nazi Germany knew of each other's ongoing efforts in their "battle of the beams".

This term is normally used for the various systems used by the Germans to direct their bombers (Lorenz, Knickebein, X-Gerat, Y-Gerat etc) and the British countermeasures like meacons, rather than radar.

The link takes to a page about Knickebein etc with nothing about radar. I think a better phrase should be substituted here. --jmb 00:11, 7 September 2007 (UTC)

Yeah.. but I think it was still an important part of the history of radar, when there was no real difference between ECM and meaconning, radars and navigation radio, amateur radio and ESM... Germ 00:24, 7 September 2007 (UTC)

The operation against the Knickenbein etc was completely separate. The phrase "Battle of the Beams" has a quite specific meaning that was nothing to do with radar. I don't understand the menion of "amateur radio and ESM" in this context. The Wiki page linked from the phrase is about the countermeasures to these systems like Knickebein. --jmb 07:16, 7 September 2007 (UTC)

Radar and ROC Curves

A "Receiver Operating Characteristic Curve" or "ROC Curve" plots the true positive 'signal' rate against the false positive signal rate (signal to noise ratio). This concept is used frequently in biomedical research to characterize the quality of diagnostic tests. This method was reportedly developed during the early years of radar in attempting to measure the 'operating characteristics' of a given radar technician (eg their ability to sort 'friend' from 'foe' during the WWII use of radar in defending Britain from German bombing raids). Does anyone know whether there is truth to this and can you provide a reference?

Bad wording

"Watt quickly wrote back that this was unlikely, and he pointed out that in the absence of progess, 'meanwhile attention is being turned to the still difficult, but less unpromising, problem of radio detection and numerical considerations on the method of detection by reflected radio waves will be submitted when required."

Really bad wording, almost incoherent. Reword it please. 64.236.245.243 15:31, 16 January 2007 (UTC)

Development in the Soviet Union in the 30's

I would like to draw your attention to the German WIKIPEDIA entries for RADAR in which the russian development are very well described. I could help if someone is going to translate it Jaypee1 10:29, 22 March 2007 (UTC)

1900s

I am sure this entry is incomplete. In the distant past (so I cannot remember title or details) I read a technical paper on the early development of German radar. Its origin, in the early 1900s, was in experiments conducted in the Baltic for the German Navy, specifically on rangefinding, using a transmitter, a receiver, and (importantly) an early oscilloscope tube for timing the returned signal. That the echo was thus electronically timed shows that the experimenter's appreciation of the potential of radar was complete. The importance of these trials was increased by a lucky accident. A Wright Flyer was being demonstrated at the same time as the radar ranging trials and a reflection from the aircraft as it passed over the target ship was observed on the tube. The significance and potential of this chance event was fully realised and noted at the time. Whether the experimenter was the Christian Huelsmeyer noted below I can not remember. If it was, the entry on his work seriously underestimates the sophistication of his apparatus, since it does not mention his use of an oscilliscope for echo timing and accurate rangefinding.

I also support Jaypeeel's comment above. The Russian Navy kept a close watch on all technology used by the German Navy, which was greatly admired, so although I have no references I would be very surprised if they failed to follow this lead.

What is really surprising is that the British Admiralty - who must have been aware of these developments - ignored them, because at that time the Rutherford Laboratory at Cambridge was well placed, in terms of equipment and scientists, to follow through and develop the German initative in radar technology.

Pfvlloyd 12:24, 27 August 2007 (UTC)

Soviet Radar, Nikola Tesla

You can find some good Russian sources for information on their radar development. For example: http://www.aroundspb.ru/guide/east/radiopolygon/radiopolygon.php Google for "Рапид", which was one of the first experimental systems (1934). P. Oshchepkova proposed the project in 1932, big support from Marshal Tukachevsky, both of them were purged in 1937.

Be careful about Nikola Tesla. I know he's an interesting character, but people get carried away about him too. It's unlikely he ever created standing waves or that his ideas would have worked at all. At best he deserves a footnote, not a whole section. Nobody got any good ideas from him. DonPMitchell (talk) 05:03, 25 September 2008 (UTC)

rm'ed Tesla section per WP:OR/WP:PST since it was wholly primary sourced. Fountains of Bryn Mawr (talk) 14:56, 17 October 2013 (UTC)

Range and Direction Finding

This new article doesn't seem to add much to the information already here. I propose merging/redirecting it here. Fences&Windows 23:31, 8 January 2010 (UTC)

This article misrepresents the primary role British technology

The article lists many valid developments that occurred around the world in the development of radar. The fact is though that it was the British who produced practical radar systems that provided the Allies with the actual advantages of Radar. As with the jet engine and other advanced technologies the USA was far behind the British in radar and when the Tizzard mission gave away these technologies to the Americans the British already had the most effective radar system that defeated the Germans during the Battle of Britain. The Royal Navy already had radar installed on all its major warships before Tizzards mission. No other navy, apart from to a limited degree the Germans, had radar of any consequence and the US Navy had no radar of any type, being years behind. The article therefore seriously misrepresents the truth by utterly failing to acknowledge the facts and by suggesting that the Tizzard mission found the Americans where at a comparable level of development with their own system. It is in fact yet another example of Wikipedia’s common use as a propaganda device no matter how urbanely or subtly exploited.86.29.63.129 (talk) 19:21, 17 April 2010 (UTC) And the article misrepresents the primary role of france in improving the british magnetron !What about the magnetron brought by Maurice Ponte in Wembley May 8 1940 ? —Preceding unsigned comment added by 121.54.67.242 (talk) 09:13, 17 April 2011 (UTC)

That's nonsense! If you can't bear other nations success you should go read some comic books but sure not Wikipedia! --92.223.57.44 (talk) 07:06, 2 November 2011 (UTC)

It is not nonsense and the OP has a point and to suggest that historical fact lies in the realm of 'comic books' reflects a basic lack of knowledge regarding the system. The British did develop radar and not to list Watson-Watt in the list of contributors is a disgrace. Twobells^t@lk 10:51, 11 February 2015 (UTC)

Lot's of people had the idea of using radio reflections for location, because it's a relatively obvious idea. If you try to construct a nationalist theory of the history of science, you're doing it wrong. Ideas flow back and forth, they build on the past, often in very small steps. Also, when hundreds of clever people think about something, they often arrive at the same ideas independently.

The magnetron tube was very important, because it let the British use smaller portable antennas. The big contribution from the MIT Radiation Lab was automatic tracking. By the end of WWII, the very advanced radar SCR-583, was really a marriage of MIT's control theory with British microwave technology. DonPMitchell (talk) 05:15, 4 February 2016 (UTC)

Fringe Theory in Section "Significance"

The section labeled "Significance" distorts history by implying that there is some sort of disagreement amongst historians regarding the degrees to which radar and the atomic bomb contributed to the victory conditions of WWII. James Gleick writes in Genius that by any reasonable calculus that radar did far more than the A-bomb did, but it -- the bomb -- captured everyone's attention in ways that radar did not. I would like to see a discussion as to why the section should not be edited to remove this fringe theory that radar did not contribute significantly to WWII victory conditions. <br. />—NBahn (talk) 05:28, 25 July 2010 (UTC)

The war was won by the people on the ground, by the people at sea, and by the people in the air. Radar made this easier, if not possible at all in the first place, e.g., Battle of the North Cape. — Preceding unsigned comment added by 95.149.173.56 (talk) 09:28, 30 July 2017 (UTC)

Ponte and Buderi quotes

I don't think there is any real contradiction between Ponte's view and Buderi's. I've edited this section to try to make it clearer that there is a big distinction between the advancement of science and that of technology. As Ponte explains, the science was already known to physicists (of all countries), and hence radar is a credit to engineers and technicians. Buderi (also correctly) points out that even if the science was not new, the technology resulted in lots of spinoffs. These are not contradictory, and belong in the same section, in my opinion.

For the quote from Ponte, the original in French should be included, since that's what he actually said, or else we should make it clear this a translation. Including the original is not too obtrusive, and lets readers judge the accuracy of the translation. Also, Ponte has changed the web version since he wrote the original quote, which is why the link goes to the archive version.

Newcomen Society talk on the history of German Radar

A summary by Dr Fred Starr:

"I hope you will pass these comments onto the author of the very interesting article Phil Judkin's talk on Luftwaffe radar was done last October....2014 As it happens I wrote up a summary of what I understood from the talk. I am still quite hazy about the technical details of the way in which the floodlighting form of British radar work. Apparently it was brought back into service during the cold war period....It may have been more difficult to jam.....I will be asking Phil about this. Here is my summary of Phil's talk. You may have noticed that the cumbersome array of aerials on German night fighters. This was because of the long wavelength hvingvto be used. The cavity magnetron permitted much shortwave lengths, so we could put everything inside the aircraft nose. Fred Personalities and Power Struggles in the Air Defence of Germany

Phil Judkins has already given the Newcomen Society the lowdown on what really happened in the development of radar in Britain. He was invited back for the October meeting to tell us about what went on with German radar and German countermeasures to the RAF Bombing Offensive. Phil told us that German radar equipment started from a different basis to that in Britain. Our priority was to detect German bombers coming to us from across the sea. We met this need with the low-tech Chain Home system, which effectively floodlit the North Sea and English Channel with radar waves. Enemy aircraft entering this zone would be detected at long range, with RAF fighters being put into visual contact. Chain Home worked well for daytime interception, during the Battle of Britain, but was almost useless in the subsequent night time Blitz.

When Bomber Command began to make a serious effort to attack Germany in 1940-41, it had to be a night time offensive. Bombers crossed into Germany, effectively one-by-one, each aircraft trying to find its way to the target. To intercept, German radar had to be able to determine the position of the attacking bomber and the defending fighter, the aim being to bring the latter into close proximity of its prey. Two highly directional beam type radars were needed to determine position, plus an additional one for altitudes.

Such equipment had been under development since the early thirties, when Rudolph Kűhnold, who was working on sonar, thought that the same principle might be used for detection of ships, if radio waves were substituted for those of sound. His device eventually evolved into the Freya, initially used by the German Navy as an early warning radar for both ships and aircraft. The German Army requirement was for a radar to work in conjunction with antiaircraft guns, where it was needed to control searchlights. TheLuftwaffe itself had little interest in what was going on. Wolfgang Martini, who had realised the importance of radar, and suspected that the British had their own system, was to some extent sidelined by Goering, who claimed not to understand “boxes with coils in them”. Ace fighter pilots like Adolf Galland did not want to be subject to ground control. And in 1942, when German night fighters were eventually equipped with airborne radar, pilots sawed through the antennae to reduce drag.

Phil pointed out that unlike the RAF, which demanded a high level of technical proficiency from its personnel, to compensate for relatively crude and manufactured equipment, a radar operator in the Luftwaffe was generally quite a poor specimen. Because of this, German equipment was sophisticated and well designed.

To meet the steady increase in the number of night time attacks, however ineffective, Josef Kammhuber set up a line of radar controlled “boxes” running north-south across Occupied Europe. But at the time the Germans didn’t have modern radar scope, which shows the positions of aircraft on a cathode ray tube, they utilised a manual version, rather like a map. Using reports from two beam type ground radars, lights were used to indicate the positions of the bomber and fighter, with the radar controller “talking” the Luftwaffepilot to a point where he was close enough to “acquire” the bomber visually.

The development of Gee by the British, as a navigational radio aid, changed everything. For the first time it allowed Bomber Command to create a mass of bombers, cutting through the Kammhuber line at one point, swamping German defences. After the 1000 bomber attack on Cologne, Kammhuber was sacked, being replaced by “Beppo” Schmid, who was, according to Phil, technically illiterate and a semi-alcoholic. Be that as it may, Beppo saw that, because the bombers were being massed together, these would provide plenty of chickens for plucking. What was needed were devices that could bring German night fighters into the bomber stream.

German ground based radar was by then properly integrated into the air defence system, and German night fighters were at last equipped with airborne radar. Wave length was too long to pick up individual aircraft but would show clusters. Furthermore, all the devices used by the British, like H2S, to improve bombing accuracy, or the Monica tail warning radar, gave out detectable signals which enabled fighters to home onto the bomber stream.

By 1943, “Window”, strips of paper coated with aluminium foil, began to be used by the RAF to jam German radar. Phil told us of a lucky break for the RAF. After inspection of a German night fighter that had landed in Britain, the lengths of window strips were cut to exactly half the wavelength of its radar emissions, giving very powerful jamming. For a time, it made German airborne radar completely useless.

However, German radar operators, with help from industry, learned to live with Window and other jamming techniques. Doppler effects from a moving aircraft and its propellers made it possible to pick out a bomber from slowly falling strips of Window. Changes in RAF tactics and equipment were quickly nullified, and Bomber Command’s task only became reasonably easy after June 1944, when after the invasion, much of the German air defence system could be bypassed.

Following Phil’s lecture there was a good discussion with requests for a follow up on what the 8th Air Force did with radar, and for a critical examination of its use by the German Navy. My own take on the proceedings was that, through ignorance and infighting, Germany had a very messy start, but by 1943 priorities had been established, with Germany wielding an extremely dangerous weapon. If Germany had not been facing round the clock bombing, and been able to put more aircraft into night fighting, it might have brought Bomber Command completely to its knees. Engineman (talk) 17:49, 17 February 2015 (UTC)

"What ifs" are always dangerous as they usually assume that if one side changes what it does, that the other side does not, and the latter carries on doing exactly what it was doing before. This is very rarely the case. — Preceding unsigned comment added by 95.149.173.56 (talk) 09:09, 30 July 2017 (UTC)

Plagiarism

While looking for additional material I found that large portions of text in the United Kingdom section are direct quotes of material in chapter 9 of the book, "A Brief History of Science with Levity", by Mike Bennett.

Reading the Wikipedia policy on plagiarism and copyright infringement I don't see how this is not in violation unless Bennett's work is a copy of Wikipedia. Given the copyright date of 2015 I suppose this is possible. I don't see an attribution of the material anywhere in Bennett's book, but Google doesn't let me see the entire book. Gnuarm (talk) 09:38, 23 February 2016 (UTC)

The Klystron

It is utterly amazing that so much verbiage could be written without using the word Klystron. Garfield Garfield 07:06, 3 March 2016 (UTC)

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October 2017

It would be rather appropriate to copy the definition of the acronym RADAR to the top. It is convention to define acronyms on first use within the document.Xalorous (talk) 17:13, 31 October 2017 (UTC)

OK, I did this. Feel free to improve, modify, remove, as appropriate. LouScheffer (talk) 19:33, 31 October 2017 (UTC)

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Unit of measurement "sm"

The United Kingdom section includes the sentence "Its accuracy, dependent on the height of the aircraft, meant that CH, capable of only 4 sm (0.0068 km), was not accurate enough to place an aircraft within its detection range, and an additional system was required." The citation is Judkins, p. 116.

I'm confused by this for two reasons. First, there is no explanation of what the "sm" unit measures, apart from the implication that it is equivalent to about 1.7 metres; and second, this seems like an extremely high degree of accuracy. A typical WW2 military aircraft is larger than 6.8 metres, so if we can place it with that degree of accuracy, it seems likely that our measured location of the aircraft will actually overlap with part of its airframe. It's an astounding level of precision, which seems unlikely.

The doctoral thesis by Judkins is available online, and does not appear to mention these items - at least, there's nothing on page 116, and I can't find anything by searching the text for "sm", "0.0068", "68", "6.8", etc. I haven't read the whole thing, which is 541 pages. Could it perhaps be square miles, and the conversion is a mistake?

181.64.237.173 (talk) 10:53, 27 September 2019 (UTC)

I tracked down the article referenced, and it just says on page 116 "First of all, Chain Home, a long-range early-warning radar, was accurate only to within 4 miles;". Presumably the person who added the information used the nonstandard abbreviation "sm" to specify the UK statute mile instead of modern international mile, which is a tiny bit longer. For reasons unknown, the conversion template seems to treat "sm" as one thousandth of a mile – I could not find it on the supposedly comprehensive list of lenght units, so I presume it being accepted by the template was accidental. Nortti0 (talk) 14:07, 15 December 2023 (UTC)

Maxwell

It seems to me that Maxwell is not quite given his proper credit here. His equations not only predict the existence of radio waves, but much of their behavior. Only the properties of materials need to be added to predict the behavior of the waves to great accuracy, and therefore to analyze any radar system whose electronic devices are understood. The electrical properties of metals were already sufficiently understood to predict efficient reflection, before Hertz. It is true that without digital computers calculations were limited, but there was a lot that could be understood analytically, directly from the equations. David R. Ingham 03:47, 19 October 2019 (UTC) — Preceding unsigned comment added by David Ransford Ingham (talk • contribs)

Claims of L L K Honeyball

He claimed to be the inventor of radar and spent years trying to get recognition for this acheivement. The source material for his claims are provided here: https://drive.google.com/drive/folders/1XydtBqRbGFMuHWnOaEnk6ZXLN9m1D5eC?usp=sharing 101.100.130.146 (talk) 01:18, 14 September 2022 (UTC)