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Dynamic range,sensivity,resolution ,noise ,eirp ,polosa signala...
milstar: 1.Receiver dynamic range --------------------------------- Stat`ja Watkins-Johnson /razr. i postawshik priemnikow spionaza wj8617 w 80-90 godi/ http://www.triquint.com/prodserv/tech_info/docs/WJ_classics/vol14_n1.pdf http://www.triquint.com/prodserv/tech_info/docs/WJ_classics/vol14_n2.pdf http://www.triquint.com/prodserv/tech_info/WJ_tech_publications.cfm Dinamicheksij diapazon radara AN/FPQ-6 programmi Appolo -bolee 120 db Antenna -8.8 metra D ,5.4-5.9 ghz ,4.8 kwt srednej,3 megawatt impulsnoj moschnosti , dalnost bolee 60 000 km ,pri raz. +-2 metra ,IF-30 mgz,polosa signala -1.6 mgz http://en.wikipedia.org/wiki/AN/FPQ-6 http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680003409_1968003409.pdf ljubitelskij priemnik smotri revue pri polose 400 herz , i ydalenii nesuchej signala pomexi 2000 herz blok. dinamicheskij diapazon -140 db ,chustw -138 db=0.028 microvolta http://www.elecraft.com/ 2. http://www.sandia.gov/RADAR/imageryka.html kollekzija image ot 35 ghz synthetic apperture radar razr.sposobnost' 4 inches -10 sm,100 millimetr polosa signala 2500 mgz Contact: To send feedback or request information about the contents of Sandia National Laboratories' synthetic aperture radar website, please contact: Nikki L. Angus Synthetic Aperture Radar Website Owner Sandia National Laboratories Albuquerque, NM 87185-1330 (505) 844-7776 (Phone) (505) 845-5491 (Fax) nlangus@sandia.gov http://www.sandia.gov/RADAR/movies.html kollekzija video s SAR Ku band i raz sposb 300 mm 3. -dbm microvolt conversion http://wa8lmf.net/miscinfo/dBm-to-Microvolts.pdf 0 dbm =224 millivolt dlja 50 ohm -47 dbm = 1 millivolt = 1000 microvolt -107 dbm = 1 microvolt -127 dbm = 0.1 microvolt -147 dbm = 0.01 microvolt -167 dbm = 0.001 microvolt = 1 nanovolt pri komnatnoj temperature tepl. schumi -174 dbm/ herz
Ответов - 76, стр:
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milstar: http://www.setron.de/_downloads/produkte/lt/238718f.pdf Fin 1 mhz 15msps SFDR -102 db ,Sinad-94.5 db
milstar: Динамический диапазон радара AN/FPQ программы Аполлон более 120 дб Антенна 8.8 метра диаметром C band 5.4-5.9 Ghz 4.8 квт средней мощности,3 мегаватта импульсной мощности промежуточная частота-30 мегагерц, полоса сигнала -1.6 мегагерц Дальность более 60 000 километров при разрешении +- 2 метра http://en.wikipedia.org/wiki/AN/FPQ-6 http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680003409_1968003409.pdf
milstar: http://www.ee.fju.edu.tw/pages/032_faculty/sclin/lecture/Rada_System_Design/Chapter7.pdf If the first-stage network has adequate gain he noise figure of the total network is primarily determined by the first stage. #########################
milstar: There's a more important reason. I don't know for sure, but it's reasonable to assume the 8617B (or a derivative of it) meets the stringent TEMPEST signal leakage criteria. Two stories from the open literature demonstrate why one might be concerned with signal leakage from electronic equipment operated in sensitive locations. Both examples are from Peter Wright's book Spycatcher First, in the 1950's the French Embassy in London used a mechanical teleprinter and an on-line encryption device so that the 5-level Baudot signals sent outside the embassy were protected by high level encryption. However, careful examination of the encrypted data pulses showed small ghost images or glitches from the source un-encrypted signals. It was thus possible to read the signals as if they were completely unencrypted. (DeGaulle was President of France at the time and relations between the UK and France were frosty.) Second, the UK's MI5 counter-intelligence operation uncovered the operating frequencies used by the Soviet Union in the UK. By using a sensitive receiver, they were able to receive the local oscillator leakage and then by adding or subtracting the associated IF frequency, they could determine the frequency to which the embassy receiver was tuned. Similar techniques are said to be used in determining whether a household has an unlicensed TV set in the UK and with computer monitors it's possible to reconstruct an almost perfect pixel-by-pixel image of a monitor from some distance. The 8617B's signal leakage specification is less than -100 dBm, which is quite effective at making these sorts of recoveries difficult to impossible. http://www.cliftonlaboratories.com/wj-8617b_receiver_impressions.htm http://www.rfcafe.com/references/articles/wj-tech-notes/Rec_dyn_range1.pdf
milstar: http://www.sm5bsz.com/dynrange/qex/bdr.pdf Blocking dynamic range
milstar: ИСТРЕБИТЕЛЬ ШЕСТОГО ПОКОЛЕНИЯ СМОЖЕТ ДЕЛАТЬ "РАДИОФОТОГРАФИИ" САМОЛЕТОВ ПРОТИВНИКА 27 июля 2017 г., AEX.RU - Создаваемый в России новейший истребитель шестого поколения, который придет на смену Т-50, сможет делать радиолокационные "фотографии" самолетов противника и без участия человека определять их тип и вооружение. Об этом сообщил в интервью ТАСС советник первого заместителя гендиректора концерна "Радиоэлектронные технологии" (КРЭТ) Владимир Михеев. По его словам, КРЭТ разрабатывает для боевого самолета будущего радиофотонный локатор, уже имеется его экспериментальный образец и создается полномасштабный макет. Новый радар значительно превзойдет все существующие радиолокационные станции (РЛС) по мощности и диапазону. "Радиофотонный радар сможет видеть, по нашим оценкам, значительно дальше существующих РЛС. А так как мы будем облучать противника в беспрецедентно широком спектре частот, то с высочайшей точностью узнаем его положение в пространстве, а после обработки получим почти фотографическое его изображение - радиовидение", - рассказал Михеев. Он пояснил, что "это важно для определения типа (самолета - прим. ТАСС): сразу и автоматически компьютер самолета сможет установить, что это летит, к примеру, F-18 с конкретными типами ракетного оружия". Новый радар за счет своей сверхширокополосности и огромного динамического диапазона приемника будет иметь большие возможности по защите от помех. Также он дополнительно будет выполнять задачи радиоэлектронной борьбы (РЭБ), передавать данные и служить средством связи. На истребителе шестого поколения будет устанавливаться "мощная многоспектральная оптическая система, работающая в различных диапазонах - лазерном, инфракрасном, ультрафиолетовом, собственно оптическом, однако значительно превышающем видимый человеком спектр", отметил Михеев. Она дополнит радиофотонный радар. В марте 2016 года курирующий "оборонку" вице-премьер РФ Дмитрий Рогозин объявил о начале работ над истребителем шестого поколения. Как сообщил ТАСС в июне прошлого года глава дирекции программ военной авиации Объединенной авиастроительной корпорации Владимир Михайлов, опытный образец российского боевого самолета шестого поколения совершит первый полет до 2025 года. В предыдущем интервью ТАСС по теме истребителя шестого поколения Михеев рассказал, что новый самолет будет делаться в двух вариантах - пилотируемом и беспилотном. Новые истребители будут действовать в "стае", возглавляемой самолетом с летчиком на борту. Беспилотники смогут нести электромагнитные пушки, летать с гиперзвуковой скоростью, выходить в ближний космос. В этот раз Михеев добавил, что беспилотный вариант получит маневренность, недоступную для пилотируемых самолетов, у которых она ограничена возможностями человека переносить перегрузки. Хотя беспилотный и пилотируемый варианты истребителя шестого поколения будут делаться на одной базе, они будут отличаться не только составом вооружения и оборудования, но и внешне. КРЭТ разрабатывает для нового истребителя БРЭО и электромагнитное оружие в инициативном порядке. Так, концерн уже создал экспериментальный образец радиофотонного радара для этого самолета. Подробне
milstar: http://samonavedenie-raket.ru/sistemy-samonavedeniya/passivnaya-infrakrasnaya-sistema-samonavedeniya
milstar: During the early 1960s, the Jet Propulsion Laboratory developed a maser to provide ultra-low-noise amplification of S-band microwave signals received from deep space probes. This maser used deeply refrigerated hydrogen[citation needed] to chill the amplifier down to a temperature of four kelvin. Amplification was achieved by exciting a ruby comb with a 12.0 gigahertz klystron. In the early years, it took days to chill, and remove the impurities from, the hydrogen lines. Refrigeration was a two-stage process with a large Linde unit on the ground, and a crosshead compressor within the antenna. The final injection was at 21 MPa (3,000 psi) through a 150 µm (0.006 in) micrometer-adjustable entry to the chamber. The whole system noise temperature looking at cold sky (2.7 kelvins in the microwave band) was 17 kelvins. This gave such a low noise figure that the Mariner IV space probe could send still pictures from Mars back to the Earth even though the output power of its radio transmitter was only 15 watts, and hence the total signal power received was only -169 decibels with respect to a milliwatt (dBm).
milstar: http://publications.lib.chalmers.se/records/fulltext/155819.pdf
milstar: 2006 IPN Progress Report 42-165 May 15, 2006 A Dual-Channel 8- to 9-Gigahertz High-Electron Mobility Transistor (HEMT) Low-Noise Amplifier (LNA) Package for the Goldstone Solar System Radar E. M. Long 1 An existing dual-polarization 8- to 9-GHz high-electron mobility transistor (HEMT) low-noise amplifier (LNA) package with an input noise temperature of 15 K has been upgraded with state-of-the-art amplifiers, a lower-loss cooled wave- guide input, and a lower operating temperature closed-cycle refrigerator (CCR). The new system exhibits an input noise temperature of 4.4 K. This noise perfor- mance is now slightly better than that of the dual-channel maser currently used for radar in the Deep Space Network at DSS 14. ################################# This article will describe the changes made to achieve this performance. https://ipnpr.jpl.nasa.gov/progress_report/42-165/165C.pdf
milstar: https://www.youtube.com/watch?feature=endscreen&NR=1&v=D1A3SqlvvgM
milstar: We can now use commercial parts for A-D converters that enable us to do direct digital sampling,” says Douglas Reep, vice president and chief engineer of the Lockheed Martin Corp. radar systems segment in Syracuse, N.Y. “We are seeing a trend where we remove analog components from systems.” “Now we can almost digitize microwave signals without the down-convert,” says Jerald Nespor, Lockheed Martin senior fellow for radar development at the company’s facility in Moorestown, N.J. “We need A-D converters with sufficient sampling rates to do that. Everyone wants higher efficiency and more dynamic range, and we can do that with COTS technologies and innovative architectures.” ------------- typical levels of target echo returns are in the range of -90 to - 120 dbm http://www.scienpress.com/Upload/JCM/Vol%204_1_11.pdf
milstar: http://www.navair.navy.mil/nawcwd/ewssa/downloads/NAWCWD%20TP%208347.pdf
milstar: http://www.northropgrumman.com/Capabilities/AWACSAPY2/Documents/AWACS.pdf
milstar: http://www.arilissone.org/uploads/contenuti/vgo/Absolute%20limits%20of%20NF%20for%20Max%20Clip%20Level%20of%20a%20receiver%20RX.pdf
milstar: achieving an SNR of 72 dBFS for a -1 dBFS single tone input signal at 190 MHz requires the RMS jitter to remain below 236 fs The SP16160CH1RB subsystem design uses an input bandwidth of 20 MHz centered at an IF frequency of 192 MHz and a sampling rate of 153.6 MSPS. By addressing the challenges of interfacing to high-speed data converters in basestation applications, the subsystem design achieves a typical Nyquist-band SNR of 71 dBFS and SFDR greater than 82 dBFS for a -1 dBFS tone. Third order modulation products that fall in-band during a two-tone test are less than -91 dBFS for a composite signal with a 1 MHz spread and combined -4 dBFS peak-to-peak amplitude. Using a surface acoustic wave (SAW) filter and CMOS buffer, the SP16160CH1RB demonstrates the effective broadband noise-reducing solution shown in Figure 3 https://www.wirelessdesignmag.com/article/2010/02/wireless-basestation-design-challenges-using-high-speed-16-bit-adcs
milstar: http://www.highfrequencyelectronics.com/Sep08/HFE0908_S_Crean.pdf For example, consider an ADC with the following speci- fications: Sample rate: 120 MHz SNR @ 120 MHz: 76 dB LPF bandwidth: 2 MHz The SNR after processing gain is improved to approxi- mately 90 dB: Hence, by utilizing a high sampling rate relative to the signal bandwidth, we can operate over a dynamic range greater than the inherent SNR Symtx Inc. has implemented a dual ADC scheme to increase digitizer dynamic range as shown in Figure 3. The design uses a high-gain channel to process low-level sig- nals and a low-gain channel to process high-level signals, with simultaneous sampling of both channels in parallel. The gain difference between the high-level and low level ADCs is compensated with an appropriate n -bit left shift to give the correct scaling. A DSP after the two ADCs then selects the correct ADC output, adjusts for gain, and merges the two to create a 20-bit word with the desired dynamic range.
milstar: The Weather Surveillance Radar, 1988 Doppler (WSR-88D), also known as NEXRAD, is the most advanced operational weather radar in the world. The fleet of 160 WSR-88D radars operate 24/7 to support the weather warning and forecast missions of the National Weather Service, FAA and DoD. Additionally, real-time radar data is made available to the nation’s academic and commercial weather enterprise. Pictured to the left is the tower, which houses the antenna (inside the radome). https://www.roc.noaa.gov/WSR88D/Engineering/NEXRADTechInfo.aspx Type: S-band, coherent chain (STALO/COHO), line modulator, klystron tube amplifier (53 dB gain typical) Frequency: 2700 to 3000 MHz Average Power: 300 to 1300 watts Pulse Widths: 1.57 and 4.71 microseconds (-6 dB points) PRF short pulse: 318 to 1304 Hz PRF long pulse: 318 to 452 Hz Phase noise (system): phase and amplitude stability better than -57 dBc, -60 dBc system goal Short pulse output spectrum: -40 dB BW is 12.4 MHz, (-80 dB at +/- 62 MHz), -80 dB at +/- 19.6 MHz for congested areas(congested areas require transmitter output bandpass filter) Antenna characteristics- Type: Parabolic dish (28 feet in diameter) with center feedhorn Polarization: Dual Pol (simultaneous horizontal and vertical transmit/receive) Gain at 2850 MHz: 45.5 dB (including radome loss) Beamwidth at 2850 MHz: 0.925 deg First sidelobe: -29 dB (others less than -40 dB beyond 10 deg) Radome: fiberglass foam sandwich frequency tuned, 39 foot truncated sphere Radome two way loss: 0.24 dB at 2850 MHz Type: Coherent (stalo/coho), first downconvert to IF Detection: digital IF with 16 bit analog to digital conversion of IF signal at 100 MHz Digital Matched Filter BW: 625 kHz, short pulse, 204 kHz, long pulse Dynamic Range: 93 dB minimum required Intermediate Frequency: 57.55 MHz System noise figure: 270K (2.7dB) Receiver Noise: -114dBm (Short Pulse), -118dBm (Long Pulse) Referenced to Antenna Port. Front end interference rejection filter: 0.5 dB BW: 700 kHz, 30 dB BW: 50 MHz, 60 dB BW: 200 MHz Point target detection RCS = 4 cm2 at 100 km ###################
milstar: Bandwidth (3 dB) 0.63 MHz (short pulse); 0.22 MHz (long pulse) Phase control Selectable Receiver channels Linear output I/Q; log output Dynamic range 95 dB max; 93 dB at 1 dB compression Minimum detectable signal -113 dBm Noise temperature 450 K Intermediate frequency 57.6 MHz Sampling rate 600 kHz https://www.nap.edu/read/10394/chapter/11#70
milstar: http://www.qsl.net/n9zia/pdf/wsr-88d.pdf
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