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Message: <blockquote data-quote="overscan (PaulMM)" data-source="post: 2810" data-attributes="member: 1">A-50 Schmel radar<blockquote>Principles of operation and characteristics "Schmel”Onboard RLS (chief designer [Pogreshaev] v. f.) works in the quasi-continuous regime with the detection of aerial targets and the the pulse during the detection of surface targets. In the quasi-continuous regime the time between two following after each other pulses corresponds only to several kilometers on the distance. Therefore, in order to remove ambiguity on the distance, are used several pulse repetition frequencies. The temporary relationships of work RLS are selected in such a way that sounding each purpose is produced at three close repetition frequencies. The sequences of sounding pulses are compared between themselves in “the coincidence circuit”, as a result of which it is obtained general frequency. Analogously with the comparison of the pulses accepted is obtained the same frequency, but only with the time delay, which depends from the range to target (Fig. 5.1.6).Interference suppression, caused by the reflection of sounding pulses from the underlying surface, is produced by the method of frequency selection, which considers the difference of Doppler frequency shifts from the underlying surface and from the aerial target. The transmitting device multichannel, is executed on the powerful output klystrons. The assigning SHF generator oscillator is executed on the crystal generator with the subsequent frequency multiplication in the varactor chain. The amplitude-phase noise of the receiving-transmitting device makes it possible to see the signal of the purpose against the background of interference from the earth.Processing radar signal combined: during the first stage - with the aid of discrete- analog device with the quartz filters, on the second - with the aid of the digital rejectors and the Doppler filters (rapid Fourier transform). The digital part of device is executed in the form special computer. IN TSCVM $$RTQVM - DIGITAL COMPUTER RLS are produced the grouping on the elements of the distance of the marks, which relate to one purpose, the measurement of azimuth and angle of elevation, the calculation of single-valued range to target according to the marks at two or three repetition frequencies, shaping of information for the mapping to the flight engineer OF RLS and delivery into onboard computing system, and also automated inspection of the technical state of equipment RLS.RLS can work in the mixed regime, in which several surveys of work in the quasi-continuous regime alternate with the survey in the usual pulsed operation with the high repetition frequency. This makes it possible to conduct simultaneous work on the detection both of air and surface targets.The antenna OF THE SURVEILLANCE RADAR with the overall dimensions of 10x1,7 m is built on the horizontal slotted waveguides. The connection of antenna with the equipment, located inside the fuselage, is achieved through the multichannel SHF rotating transition and the low-frequency contact revolving device. The antenna coupling of national recognition and radio links of control is organized according to the same principle.</blockquote></blockquote>

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