The radio intelligence of the German troops in WWI quite successfully intercepted the radio communications of the Russian army headquarters and corps radio stations of the 1st and 2nd armies, which were advancing in August 1914 in East Prussia. Unfortunately, this was the result of an open disregard for the rule of secrecy by the Russian troops: often operational orders of the army commanders were broadcast in plain text. In many respects, this situation has developed due to the weak provision of ciphers. General Hindenburg and his 8th Army were well aware of the intentions and movement of the Russian troops. The result was the disaster of the East Prussian offensive.
The Germans left the barrier of the 1st Army of Pavel Karlovich Rennekampf, and the 2nd Army of General Alexander Vasilyevich Samsonov was surrounded and defeated. In this regard, the German General Hoffmann wrote:
“The Russian radio station transmitted the order in unencrypted form, and we intercepted it. This was the first of a series of countless orders transmitted from the Russians at first with incredible frivolity. Such frivolity greatly facilitated the conduct of the war in the East, sometimes only thanks to him and in general it was possible to conduct operations."
In fairness, it is worth mentioning that the Germans previously behaved in a similar way: they broadcast the text on the radio without any preparation, which helped the French in the battle of the Marne in September 1914.
In the First World War, a somewhat paradoxical situation developed: the special services preferred not to jam the enemy's radio stations, but to intercept messages with subsequent decryption. Moreover, none of the belligerents possessed serious message encryption mechanisms. In the navies of England and the United States, the methods of direction finding of radio transmissions of German submarines were actively introduced, which made it possible to direct strike ships to the areas of their deployment. Since 1915, on the Western Front, the British and French have adopted radio goniometric systems to determine the location of enemy headquarters radio stations. Later, a similar technique came to all countries involved in the world conflict. For example, the Russian army in the middle of 1915 had 24 radio direction-finding stations, which were subordinate to the headquarters of the armies. The radio intelligence service of the Baltic Fleet under the leadership of Admiral Adrian Ivanovich Nepenin was one of the most effective units in its field.
Magdeburg went to sea
Magdeburg ran aground
In many respects, the success of the service was ensured by the crash in the Baltic on August 26, 1914, according to the old style, of the light cruiser Magdeburg. The point is in his signal books and encryption documents, which Russian divers managed to raise from the bottom of the sea. In addition, the intelligence work of the coalition provided invaluable assistance. The Russian fleet in 1914-1915 had a whole set of the latest ship and coastal radio direction-finding stations. Directly in the Baltic, eight such posts worked at once.
Cruiser Breslau
Among the few episodes of the use of radio interference, the most famous was the work of the German cruisers Goeben and Breslau to "clog" the radio signals of British ships during the breakthrough of the Germans through the Mediterranean Sea to Turkey in August 1914. On the side of the German fleet were powerful and modern Telefunken radio stations for their time, the signal of which suppressed the outdated British equipment.
There is information about the use of jamming and false radio guidance signals by the Western allies against the radio stations of the German zeppelin airships that raided Great Britain. So, during a major raid of 11 "Zeppelin" on England on October 19-20, 1917, the transmission of false radio signals by powerful radio transmitters from the Eiffel Tower in Paris, relayed by another radio station, led to disorientation of the "Zeppelin" radio operators, who used signals from German radio stations for night navigation. The tactics proved to be very effective - two airships, L50 and L55, were so disoriented that they crashed in bad weather and visibility. The fighters of France and Great Britain also coped well with the defensive task and shot down three more Zeppelins.
L50 and L55 are airships that were killed during the raid on the British Isles. They were among the first victims of electronic warfare.
In World War II, electronic warfare finally took shape as an important direction in the development of military thought and technology. The primary task that was set for the electronic warfare was the opposition to the novelty of those years - the radar station. Even before the war, Germany and Great Britain began deploying a radar network to detect and track enemy aircraft. They put into service and ship radars, engaged in the detection of surface, air targets, as well as participating in fire control. The Chain Home radar system along the English Channel and the east coast in Great Britain was created back in 1937-1938 and consisted of 20 AMES (Air Ministry Experimental Station) Type I radars, operating in the range of 10-15 meters. Later, in 1939, the British Isles radar shield was supplemented with the Chain Home Low or AMES Type II low-altitude detectors with a reduced wavelength. AMES Type V became the most advanced generation of radars, in which the length of the radio wave was only 1.5 meters, and the detection range of air targets exceeded 350 km. With such a threat now had to be reckoned with, and engineers in the military departments began to develop systems for both detection of radars and their suppression. The leaders of the pre-war period in this direction were Great Britain and Germany.
The future electronic reconnaissance aircraft LZ 130 Graf Zeppelin is under construction
The Germans in 1939 (May 31 and August 2-4) decided to monitor the new British Chain Home system and equipped the LZ 130 Graf Zeppelin airship for this. The flying spy was equipped with electronic reconnaissance equipment and had to determine the location of all British radars. But the air defense of England turned off all the locators in advance and the airship went home not salty. Until now, historians have not been able to explain - the British turned off the technology only at the sight of the airship, having seen through its mission, or knew in advance about the tasks of the "zeppelin" from undercover sources. It is noteworthy that the Germans still experienced additional difficulties from their own coastal navigation system Knickbein, which operated in the centimeter range and interfered with the LZ 130 Graf Zeppelin reconnaissance equipment.
It was Knickbein that became a priority target for British EW specialists from the very beginning of the war - German bombers used this radio navigation system during raids on the islands. The British received basic data on the parameters of the Knickebein from intelligence sources in 1940 and immediately began working out measures to suppress it. Avro Anson aircraft were equipped with a set of American Halicrafters S-27 radios operating in the 30-33 MHz range, which made it possible to determine the location of German Knickebein transmitters. As soon as the map of the location of the German radio navigation equipment was installed, a network of weak emitters appeared on the British coast, which interfered in the range of Knickebein. The result was a partial and even complete disorientation of the German bomber aviation. The literature even describes cases when the Germans mistakenly landed their aircraft on British airfields. Naturally, after the night bombing.
Map showing the locations of the Knickebein transmitters. An example of two-beam guidance of bomber aircraft on a British Derby
Knickebein Emitter Antenna
The Luftwaffe leadership was aware that the Knickebein was imperfect and had low noise immunity. Even before the war, a group of German engineer Josef Pendl developed the X-Gerate (Wotan I) radio navigation system. The principle of operation of the novelty was based on a narrow-beam radio illumination (range 60-70 MHz) from special ground stations.
Diagram illustrating the technique of "blind" landing of an aircraft at an airfield. Developed by the Berlin office of C. Lorenz AG in the early 30s. Similarly, the British planted German bombers lost at night on their airfields.
The first successful application was radio navigation during the famous German air raid on Coventry in November 1940. At the beginning of the work of X-Gerate, the British panicked a little, because due to the incorrect determination of the modulation frequency, they could not deliver effective interference. And only the Heinckel He 111 bomber with receiving equipment on board, shot down on November 6, 1940, made it possible to finally understand the intricacies of German navigation. And already on November 19, the British successfully jammed the X-Gerate during the Luftwaffe bombing raid on Birmingham. The British even built false narrow-beam radio illumination stations, which were supposed to mislead the navigators of the German bombers. But the effectiveness of such measures was often low due to the fact that the inclusion of English doubles had to be synchronized with the X-Gerate, and this was difficult.
