Articoli di riviste: "Microwave receivers"

1

Sreehari Rao, R. "Emerging Trends in Microwave Receivers". IETE Journal of Research 54, n. 2 (marzo 2008): 85–95. http://dx.doi.org/10.1080/03772063.2008.10876187.

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Cochran, S. R. "Microwave amplifier based RF optical receivers". Electronics Letters 23, n. 24 (1987): 1283. http://dx.doi.org/10.1049/el:19870889.

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3

Song, Shijie, Xiaoke Yi, Lu Gan, Wenjian Yang, Linh Nguyen, Suen Chew, Liwei Li e Robert Minasian. "Photonic-Assisted Scanning Receivers for Microwave Frequency Measurement". Applied Sciences 9, n. 2 (17 gennaio 2019): 328. http://dx.doi.org/10.3390/app9020328.

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We present a novel technique based on matrix pencil assisted deconvolution to improve the measurement resolution in scanning receiver systems for microwave frequency measurements. By modeling the scanning receiver output as the cross-correlation of the input modulated signal with the filter’s spectral response and applying the matrix pencil algorithm to convolve the detected optical signal at the receiver output, our technique offers precise estimations of both the frequency and power information of microwave signals with an improved measurement resolution. A multi-tone microwave signal measurement based on an optical filter is experimentally demonstrated, showing a significant measurement resolution reduction from 1 GHz to 0.4 GHz for two radio frequency (RF) tones, which is only about 30.2% of the optical filter bandwidth.

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4

HATTORI, Kunihiko, Akira ANDO e Masaaki INUTAKE. "Multi-Channel Microwave Reflectometer with Fermi Antenna Receivers". Plasma and Fusion Research 2 (2007): S1039. http://dx.doi.org/10.1585/pfr.2.s1039.

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5

Alder, C. J., C. R. Brewitt-Taylor, M. Dixon, R. D. Hodges, L. D. Irving e H. D. Rees. "Microwave and millimetre-wave receivers with integral antenna". IEE Proceedings H Microwaves, Antennas and Propagation 138, n. 3 (1991): 253. http://dx.doi.org/10.1049/ip-h-2.1991.0041.

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6

Sen, A. K., R. Bera, M. K. Sen Gupta, S. K. Dutta, G. Tarafdar, A. Mitra, S. S. Dey et al. "EMI/EMC in Microwave and Millimeter Wave Receivers". IETE Technical Review 7, n. 2 (marzo 1990): 120–25. http://dx.doi.org/10.1080/02564602.1990.11438602.

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7

Mathur, Manisha, Jaynendra Kumar Rai e Nilakantan Sridhar. "Microwave photonic network for active electronically scanned array radar". International Journal of Microwave and Wireless Technologies 9, n. 3 (3 marzo 2016): 543–50. http://dx.doi.org/10.1017/s1759078716000295.

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Active electronically scanned array (AESA) radar has large number oftransmit/Receive (T/R) modules which require multiple microwave and digital signals. Distribution of these signals through conventional method such as coaxial cable, twisted pair, etc. not only introduces engineering complexities and signal loss but also have limitation of bandwidth, data rate, transmission distance, etc. This paper addresses design and implementation of microwave photonic network for distribution of microwave and digital signals over single optical fiber using wavelength division multiplexing for AESA radars. The design challenge is to limit the variation in output radio frequency power within ±1 dB over full operational band of radar from 2 to 4 GHz and functionality under hostile military environment. Optical amplifiers have been used in all channels to stabilize optical output independent of wavelength with automatic light control. The optical signal is split into 64 identical parts to feed multiplexed signal into different digital receivers physically spread across the antenna array. It is an additional challenge to normalize performance as all 64 receivers show variation in output in spite of identical electronic circuitry. Experimental results validate the feasibility of microwave photonic network for wide branching distribution of multiple microwave and digital signals for AESA radar.

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Cochran, S. R. "Low-noise receivers for fiber-optic microwave signal transmission". Journal of Lightwave Technology 6, n. 8 (1988): 1328–37. http://dx.doi.org/10.1109/50.4138.

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Gheidi, Hamed, e Ali Banai. "An Ultra-Broadband Direct Demodulator for Microwave FM Receivers". IEEE Transactions on Microwave Theory and Techniques 59, n. 8 (agosto 2011): 2131–39. http://dx.doi.org/10.1109/tmtt.2011.2144993.

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Adam, J. D., e S. N. Stitzer. "Frequency selective limiters for high dynamic range microwave receivers". IEEE Transactions on Microwave Theory and Techniques 41, n. 12 (1993): 2227–31. http://dx.doi.org/10.1109/22.260710.

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Alameh, K. E., e R. A. Minasian. "Tuned optical receivers for microwave subcarrier multiplexed lightwave systems". IEEE Transactions on Microwave Theory and Techniques 38, n. 5 (maggio 1990): 546–51. http://dx.doi.org/10.1109/22.54922.

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12

Mukhanov, Oleg, Georgy Prokopenko e Robert Romanofsky. "Quantum Sensitivity: Superconducting Quantum Interference Filter-Based Microwave Receivers". IEEE Microwave Magazine 15, n. 6 (settembre 2014): 57–65. http://dx.doi.org/10.1109/mmm.2014.2332421.

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13

Ramaswamy, Anand, Leif A. Johansson, Jonathan Klamkin, Hsu-Feng Chou, Colin Sheldon, Mark J. Rodwell, Larry A. Coldren e John E. Bowers. "Integrated Coherent Receivers for High-Linearity Microwave Photonic Links". Journal of Lightwave Technology 26, n. 1 (2008): 209–16. http://dx.doi.org/10.1109/jlt.2007.911899.

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14

Meaney, Paul, Alexander Hartov, Timothy Raynolds, Cynthia Davis, Sebastian Richter, Florian Schoenberger, Shireen Geimer e Keith Paulsen. "Low Cost, High Performance, 16-Channel Microwave Measurement System for Tomographic Applications". Sensors 20, n. 18 (22 settembre 2020): 5436. http://dx.doi.org/10.3390/s20185436.

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We have developed a multichannel software defined radio-based transceiver measurement system for use in general microwave tomographic applications. The unit is compact enough to fit conveniently underneath the current illumination tank of the Dartmouth microwave breast imaging system. The system includes 16 channels that can both transmit and receive and it operates from 500 MHz to 2.5 GHz while measuring signals down to −140 dBm. As is the case with multichannel systems, cross-channel leakage is an important specification and must be lower than the noise floors for each receiver. This design exploits the isolation inherent when the individual receivers for each channel are physically separate; however, these challenging specifications require more involved signal isolation techniques at both the system design level and the individual, shielded component level. We describe the isolation design techniques for the critical system elements and demonstrate specification compliance at both the component and system level.

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15

Bingham, S. J., B. Börger, D. Suter e A. J. Thomson. "The design and sensitivity of microwave frequency optical heterodyne receivers". Review of Scientific Instruments 69, n. 9 (settembre 1998): 3403–9. http://dx.doi.org/10.1063/1.1149107.

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16

Ryabchun, S., C. Y. E. Tong, R. Blundell e G. Gol'tsman. "Stabilization Scheme for Hot-Electron Bolometer Receivers Using Microwave Radiation". IEEE Transactions on Applied Superconductivity 19, n. 1 (febbraio 2009): 14–19. http://dx.doi.org/10.1109/tasc.2008.2008398.

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17

Fuster, J. M., J. Marti, V. Polo e J. L. Corral. "Fiber-optic microwave link employing optically amplified electrooptical upconverting receivers". IEEE Photonics Technology Letters 9, n. 8 (agosto 1997): 1161–63. http://dx.doi.org/10.1109/68.605536.

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18

Chapurskii, V. V., G. P. Slukin, M. I. Noniashvili e G. A. Lesnikov. "Ground-Based MIMO Microwave Cameras: Resolution and Stationary Object Imaging". Herald of the Bauman Moscow State Technical University. Series Instrument Engineering, n. 3 (126) (giugno 2019): 77–94. http://dx.doi.org/10.18698/0236-3933-2019-3-77-94.

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The study analysed possible resolution of two ground-based MIMO microwave camera designs by means of two-dimensional spatial cross-sections of a generalized ambiguity function. We used stepped-frequency modulated broadband signals as time-orthogonal probing signals for the microwave camera transmitters. We employed a mathematical simulation of the space-time signal processing system pertaining to MIMO microwave camera receivers to illustrate 2D and 3D microwave imaging of stationary extended multipoint objects situated at various altitudes above the earth surface.

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Oosterbeek, Johan W., Neha Chaudhary, Matthias Hirsch, Udo Höfel e Robert C. Wolf. "Assessment of ECH stray radiation levels at the W7-X Michelson Interferometer and Profile Reflectometer". EPJ Web of Conferences 203 (2019): 03010. http://dx.doi.org/10.1051/epjconf/201920303010.

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Electron Cyclotron Heating and Electron Cyclotron Current Drive are key components for heating and control in magnetically confined fusion plasmas. The high power microwaves are not always completely absorbed leading to stray radiation [1], [2]. At W7-X, the total injected microwave power can be up to 7.5 MW @140 GHz while the entire Electron Cyclotron Emission picked-up by an observer at the edge of the plasma is a fraction of a mW. In the situation of a Michelson Interferometer, the principle measurement is the entire ECE spectrum. Thus, any stray radiation is bound to enter the spectrum. In this work initial stray radiation measurements without filters at the location of two microwave receivers -the Michelson Interferometer and the Profile Reflectometer -are discussed. The data is used to dimension a notch filter to be used with the broad band Michelson Interferometer.

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20

Petrov, S. A. "“Digital” Approaches to Expanding the Dynamic Range of Broadband Microwave Receivers". Ural Radio Engineering Journal 3, n. 4 (2019): 356–68. http://dx.doi.org/10.15826/urej.2019.3.4.002.

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21

Liou, Yuei-An, Cheng-Yung Huang e Yu-Tun Teng. "Precipitable water observed by ground-based GPS receivers and microwave radiometry". Earth, Planets and Space 52, n. 6 (giugno 2000): 445–50. http://dx.doi.org/10.1186/bf03352256.

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22

El-Motaafy, Hosny, e Mamdouh Ibrahim. "DESIGN AND IMPLEMENTATION OF MICROWAVE PARTS OF AIRBORNE-RADAR-WARNING RECEIVERS". International Conference on Aerospace Sciences and Aviation Technology 5, ASAT CONFERENCE (1 maggio 1993): 1–10. http://dx.doi.org/10.21608/asat.1993.25640.

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23

Mosso, M. M., e A. Podcameni. "Dual-mode dielectric resonator frequency/phase discriminator for narrowband microwave receivers". Electronics Letters 31, n. 1 (5 gennaio 1995): 46–47. http://dx.doi.org/10.1049/el:19950021.

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24

Saunders, Richard. "The Microwave Background from Cambridge". Highlights of Astronomy 7 (1986): 325–31. http://dx.doi.org/10.1017/s1539299600006596.

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Microwave background astronomy has arrived. Largely because of improvements in receivers, the last three years have seen the emergence of agreement concerning important measurements of the microwave background radiation (MBR):– hard evidence that the MBR has a black-body spectrum (see Smoot in these proceedings);– the unambiguous detection of the Sunyaev-Zeldovich decrement in clusters of galaxies (Birkinshaw et al 1984), and indeed profiles of the decrement across clusters (Birkinshaw in these proceedings);– the lack of anisotropy in the MBR temperature T on scales of a few arcmin down to ΔT/T˜5×10-5 (Uson & Wilkinson 1984; Readhead, private communication) and the consequent elimination of simple theories of adiabatic primordial fluctuations.

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Razavian, Mojtaba, Mohammad Hossein Hosseini e Reza Safian. "TIME-REVERSAL MICROWAVE IMAGING BASED ON RANDOM CONFIGURATION OF TRANSMITTERS OR RECEIVERS". Progress In Electromagnetics Research B 56 (2013): 235–50. http://dx.doi.org/10.2528/pierb13080801.

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26

Costanzo, Alessandra, Aldo Romani, Diego Masotti, Nicola Arbizzani e Vittorio Rizzoli. "RF/baseband co-design of switching receivers for multiband microwave energy harvesting". Sensors and Actuators A: Physical 179 (giugno 2012): 158–68. http://dx.doi.org/10.1016/j.sna.2012.02.005.

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27

Marin, M., D. F. Hewit, P. K. Lee e R. S. Tucker. "Low noise tuned optical receivers using commercial 50 Ω modular microwave amplifiers". Electronics Letters 27, n. 15 (1991): 1378. http://dx.doi.org/10.1049/el:19910866.

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28

Casas, Francisco J., David Ortiz, Beatriz Aja, Luisa de la Fuente, Eduardo Artal, Rubén Ruiz e Jesús M. Mirapeix. "A Microwave Polarimeter Demonstrator for Astronomy with Near-Infra-Red Up-Conversion for Optical Correlation and Detection". Sensors 19, n. 8 (19 aprile 2019): 1870. http://dx.doi.org/10.3390/s19081870.

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This paper presents a 10 to 20 GHz bandwidth microwave polarimeter demonstrator, based on the implementation of a near-infra-red frequency up-conversion stage that allows both the optical correlation, when operating as a synthesized-image interferometer, and signal detection, when operating as a direct-image instrument. The proposed idea is oriented towards the implementation of ultra-sensitive instruments presenting several dozens or even thousands of microwave receivers operating in the lowest bands of the cosmic microwave background. In this work, an electro-optical back-end module replaces the usual microwave detection stage with Mach–Zehnder modulators for the frequency up-conversion, and an optical stage for the signals correlation and detection at near-infra-red wavelengths (1550 nm). As interferometer, the instrument is able to correlate the signals of large-format instruments, while operating as a direct imaging instrument also presents advantages in terms of the possibility of implementing the optical back end by means of photonic integrated circuits to achieve reductions in cost, weight, size, and power consumption. A linearly polarized input wave, with a variable polar angle, is used as a signal source for laboratory tests. The receiver demonstrator has proved its capabilities of being used as a new microwave-photonic polarimeter for the study of the lowest bands of cosmic microwave background.

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Huang, Ying Zhu, Sheng Wei Zhang, Yu Zhang e Jie Ying He. "Effects Analysis of Mobile Phone’s Signal to Space-Borne Radiometer". Key Engineering Materials 467-469 (febbraio 2011): 241–46. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.241.

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This paper investigates the mobile phone’s interference to the 183.31 GHz receivers of the MWHS (Microwave Humidity Sounder) in the FY-3 Meteorological Satellite by a set of related experiments, by which way finds the interfering path. And it analyses the influence of the mobile station’s interference to the orbiting Space-borne Microwave Radiometer in theory. The factors related to the jamming distance and their forces are analyzed. The way to prevent and resolve the interference is proposed and it has been proved by the experiment.

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Kravets, A. V., G. G. Galustov, A. S. Khazza e S. P. Brovchenko. "METHOD FOR REDUCTION OF NOISE TEMPERATURE AT THE INPUT OF MICROWAVE RADIO RECEIVERS". Telecommunications and Radio Engineering 69, n. 13 (2010): 1179–85. http://dx.doi.org/10.1615/telecomradeng.v69.i13.50.

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31

Barkats, D., C. Bischoff, P. Farese, T. Gaier, J. O. Gundersen, M. M. Hedman, L. Hyatt et al. "Cosmic Microwave Background Polarimetry Using Correlation Receivers with the PIQUE and CAPMAP Experiments". Astrophysical Journal Supplement Series 159, n. 1 (luglio 2005): 1–26. http://dx.doi.org/10.1086/430208.

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Mirzavand, R., A. Mohammadi e A. Abdipour. "Low-cost implementation of broadband microwave receivers in Ka-band using multiport structures". IET Microwaves, Antennas & Propagation 3, n. 3 (2009): 483. http://dx.doi.org/10.1049/iet-map.2008.0079.

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Peverini, O. A., G. Virone, G. Addamo e R. Tascone. "Development of passive microwave antenna-feed systems for wide-band dual-polarisation receivers". IET Microwaves, Antennas & Propagation 5, n. 8 (2011): 1008. http://dx.doi.org/10.1049/iet-map.2010.0340.

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34

Baylis, Charles, Robert J. Marks e Lawrence Cohen. "Pareto optimization of radar receiver low-noise amplifier source impedance for low noise and high gain". International Journal of Microwave and Wireless Technologies 8, n. 8 (20 novembre 2015): 1133–39. http://dx.doi.org/10.1017/s1759078715001610.

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In radar receivers, the low noise amplifier(LNA)must provide very low noise figure and high gain to successfully receive very low signals reflected off of illuminated targets. Obtaining low noise figure and high gain, unfortunately, is a well-known trade-off that has been carefully negotiated by design engineers for years. This paper presents a fundamental solution method for the source reflection coefficient providing the maximum available gain under a given noise figure constraint, and also for the lowest possible noise figure under a gain constraint. The design approach is based solely on the small-signal S-parameters and noise parameters of the device; no additional measurements or information are required. This method is demonstrated through examples. The results are expected to find application in design of LNAs and in real-time reconfigurable amplifiers for microwave communication and radar receivers.

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Magnuski, Mirosław, Maciej Surma e Dariusz Wójcik. "Broadband Input Block of Radio Receiver for Software-Defined Radio Devices". International Journal of Electronics and Telecommunications 60, n. 3 (28 ottobre 2014): 233–38. http://dx.doi.org/10.2478/eletel-2014-0029.

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Abstract In the paper a cost-effective input block of the SDR receiver for 0.9 — 2.4 GHz frequency band built of capacitive-tuned selective amplifier and broadband Vivaldi antenna is presented. The applied selective amplifier consists of three identical sections of tunable filters and two stages of monolithic broadband amplifiers. The single filter section proposed by the authors, due to its ability to absorb parasitic inductances of varicap diodes, simplifies usage of encapsulated varicap diodes in design of tunable in broad band selective filters dedicated to input stages of the receivers. Moreover, proposed filter section has small variation of in-band insertion loss in comparison to varicap-tuned filters built of coupled transmission lines which are commonly applied in input blocks of the microwave receivers. The described selective amplifier could be easily integrated on a single substrate with the Vivaldi antenna which is a cost effective way of fabrication of the tunable in broad band input block of a receiver that has desired gain, selectivity and directivity of the antenna.

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36

Zhao, Yue Feng, e Jing Li. "Development of Microwave Limb Sounder". Key Engineering Materials 500 (gennaio 2012): 204–11. http://dx.doi.org/10.4028/www.scientific.net/kem.500.204.

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Microwave limb sounding is powerful to measure atmospheric compositions, temperature and pressure with high vertical resolution. During the past few decades many countries have developed several Microwave limb sounders to improve our understanding of stratospheric ozone chemistry and dynamics, the interaction of composition and climate and pollution in the upper troposphere. This issue will outline five existed MLS instrument and analyze their adopted techniques for lower noise and higher sensitivity as well as their capabilities comparisons. In American, the Jet Propulsion Laboratory (JPL) has already developed three MLS instruments: the UARS-MLS, EOS-MLS and CAMEO-SMLS which is ready for launch in 2011. In Japan, its JEM/SMILES is the first MLS instrument to use superconductor-insulator-superconductor (SIS) mixers with a mechanical 4-K refrigerator in space. In Sweden, the millimeter and sub millimeter limb-emission sounder on Odin uses actively cooled Schottky receivers with auto-correlators and wide hand AOS.

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Galustov, G. G., S. P. Brovchenko, D. V. Mirvoda e S. N. Meleshkin. "FEATURES OF IMPLEMENTATION OF BUILT-IN CONTROL IN HIGH-FREQUENCY PATHS OF MICROWAVE RECEIVERS". Telecommunications and Radio Engineering 71, n. 19 (2012): 1761–67. http://dx.doi.org/10.1615/telecomradeng.v71.i19.50.

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Nieminen, Teemu, Pasi Lähteenmäki, Zhenbing Tan, Daniel Cox e Pertti J. Hakonen. "Low-noise correlation measurements based on software-defined-radio receivers and cooled microwave amplifiers". Review of Scientific Instruments 87, n. 11 (novembre 2016): 114706. http://dx.doi.org/10.1063/1.4966971.

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Kulke, R., G. Möllenbeck, C. Günner, P. Uhlig, K. H. Drüe, S. Humbla, J. Müller et al. "Ceramic Microwave Circuits for Satellite Communication". Journal of Microelectronics and Electronic Packaging 6, n. 1 (1 gennaio 2009): 27–31. http://dx.doi.org/10.4071/1551-4897-6.1.27.

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KERAMIS is the acronym of a German research and development project funded by the German Space Agency (DLR) and the Federal Ministry of Economics and Technology (BMWI). The consortium is developing an RF circuit technology for Ka band multimedia satellite applications. A set of modules has been designed, manufactured, and tested by the partners of the consortium. The goal of this effort is to qualify the KERAMIS technology for space applications and to participate in an on-orbit-verification (OOV) program of the DLR. The launch of the technology verification satellite (TET) is scheduled for late 2010. This paper will give an overview of innovative circuit and module designs as well as the assembly, integration, and test results of the project. The authors will present a modular circuit concept for state-of-the-art transmitters and receivers in space at around 20 GHz. Selected modules are a 4 × 4 switch matrix, two synthesizers, and other RF modules. All circuits are based on multilayer ceramic (LTCC) including passive components, transitions, housings, and DC supply.

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Criado, Á. R., J. Montero-dePaz, C. de Dios, L. E. García, D. Segovia e P. Acedo. "Photonic Heterodyne Pixel for Imaging Arrays at Microwave and MM-Wave Frequencies". Advances in Optical Technologies 2012 (18 ottobre 2012): 1–7. http://dx.doi.org/10.1155/2012/792571.

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The use of photonic heterodyne receivers based on semiconductor optical amplifiers to be used in imaging arrays at several GHz frequencies is evaluated. With this objective, a imaging array based on such photonic pixels has been fabricated and characterized. Each of the receiving optoelectronic pixels is composed of an antipodal linear tapered slot antenna (LTSA) that sends the received RF signal directly to the electrical port of a semiconductor opticalamplifier (SOA) acting as the optoelectronic mixer. Both the local oscillator (LO) and the intermediate frequency (IF) signals are directly distributed to/from the array pixels using fiber optics, that allows for remote LO generation and IF processing to recover the image. The results shown in this work demonstrate that the performances of the optoelectronic imaging array are similar to a reference all-electronic array, revealing the possibility of using this photonic architecture in future high-density, scalable, compact imaging arrays in microwave and millimeter wave ranges.

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Cui, Tie Jun, Shuo Liu, Guo Dong Bai e Qian Ma. "Direct Transmission of Digital Message via Programmable Coding Metasurface". Research 2019 (16 gennaio 2019): 1–12. http://dx.doi.org/10.34133/2019/2584509.

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In modern wireless communications, digital information is firstly converted to analog signal by a digital-analog convertor, which is then mixed to high-frequency microwave to be transmitted through a series of devices including modulator, mixer, amplifier, filter, and antenna and is finally received by terminals via a reversed process. Although the wireless communication systems have evolved significantly over the past thirty years, the basic architecture has not been challenged. Here, we propose a method to transmit digital information directly via programmable coding metasurface. Since the coding metasurface is composed of ‘0’ and ‘1’ digital units with opposite phase responses, the digital information can be directly modulated to the metasurface with certain coding sequences and sent to space under the illumination of feeding antenna. The information, being modulated in radiation patterns of the metasurface, can be correctly received by multiple receivers distributed in different locations. This method provides a completely new architecture for wireless communications without using complicated digital-analog convertor and a series of active/passive microwave devices. We build up a prototype to validate the new architecture experimentally, which may find promising applications where information security is highly demanded.

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Cui, Tie Jun, Shuo Liu, Guo Dong Bai e Qian Ma. "Direct Transmission of Digital Message via Programmable Coding Metasurface". Research 2019 (16 gennaio 2019): 1–12. http://dx.doi.org/10.1155/2019/2584509.

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Abstract (sommario):

In modern wireless communications, digital information is firstly converted to analog signal by a digital-analog convertor, which is then mixed to high-frequency microwave to be transmitted through a series of devices including modulator, mixer, amplifier, filter, and antenna and is finally received by terminals via a reversed process. Although the wireless communication systems have evolved significantly over the past thirty years, the basic architecture has not been challenged. Here, we propose a method to transmit digital information directly via programmable coding metasurface. Since the coding metasurface is composed of ‘0’ and ‘1’ digital units with opposite phase responses, the digital information can be directly modulated to the metasurface with certain coding sequences and sent to space under the illumination of feeding antenna. The information, being modulated in radiation patterns of the metasurface, can be correctly received by multiple receivers distributed in different locations. This method provides a completely new architecture for wireless communications without using complicated digital-analog convertor and a series of active/passive microwave devices. We build up a prototype to validate the new architecture experimentally, which may find promising applications where information security is highly demanded.

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Koshelets, V. P., S. A. Kovtonyuk, I. L. Serpuchenko, L. V. Filippenko e A. V. Shchukin. "High quality Nb-AlO/sub x/-Nb junctions for microwave receivers and SFQ logic device". IEEE Transactions on Magnetics 27, n. 2 (marzo 1991): 3141–44. http://dx.doi.org/10.1109/20.133877.

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Amineh, Reza K., Maryam Ravan, Justin McCombe e Natalia K. Nikolova. "Three-Dimensional Microwave Holographic Imaging Employing Forward-Scattered Waves Only". International Journal of Antennas and Propagation 2013 (2013): 1–15. http://dx.doi.org/10.1155/2013/897287.

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We propose a three-dimensional microwave holographic imaging method based on the forward-scattered waves only. In the proposed method, one transmitter and multiple receivers perform together a two-dimensional scan on two planar apertures on opposite sides of the inspected domain. The ability to achieve three-dimensional imaging without back-scattered waves enables the imaging of high-loss objects, for example, tissues, where the back-scattered waves may not be available due to low signal-to-noise ratio or nonreciprocal measurement setup. The simulation and experimental results demonstrate the satisfactory performance of the proposed method in providing three-dimensional images. Resolution limits are derived and confirmed with simulation examples.

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Pardo, J. R., M. Ridal, D. Murtagh e J. Cernicharo. "Microwave temperature and pressure measurements with the Odin satellite: I. Observational method". Canadian Journal of Physics 80, n. 4 (1 marzo 2002): 443–54. http://dx.doi.org/10.1139/p01-158.

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The Odin satellite is equipped with millimetre and sub-millimetre receivers for observations of several molecular lines in the middle and upper atmosphere of our planet (~25100 km, the particular altitude range depending on the species) for studies in dynamics, chemistry, and energy transfer in these regions. The same receivers are also used to observe molecules in outer space, this being the astrophysical share of the project. Among the atmospheric lines that can be observed, we find two corresponding to molecular oxygen (118.75 GHz and 487.25 GHz). These lines can be used for retrievals of the atmospheric temperature vertical profile. In this paper, we describe the radiative-transfer modeling for O2 in the middle and upper atmosphere that we will use as a basis for the retrieval algorithms. Two different observation modes have been planned for Odin, the three-channel operational mode and a high-resolution mode. The first one will determine the temperature and pressure on an operational basis using the oxygen line at 118.75 GHz, while the latter can be used for measurements of both O2 lines, during a small fraction of the total available time for aeronomy, aimed at checking the particular details of the radiative transfer near O2 lines at very high altitudes (>70 km). The Odin temperature measurements are expected to cover the altitude range ~3090 km. PACS Nos.: 07.57Mj, 94.10Dy, 95.75Rs

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46

Boggess, Nancy W. "The Cosmic Background Explorer (COBE): Mission and Science Overview". Highlights of Astronomy 9 (1992): 273–74. http://dx.doi.org/10.1017/s1539299600009047.

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Ever since the discovery in 1964 of the Cosmic Microwave Background (CMB), scientists have tried to make accurate measurements of its spectrum and anisotropie3. With the successful COBE mission, major advances in our understanding of the very early universe have been achieved.COBE’s complement of instruments are the Far Infrared Absolute Spectrophotometer (FIRAS), the Differential Microwave Radiometers (DMR), and the Diffuse Infrared Background Experiment (DIRBE). FIRAS and DIRBE are located inside a 4He dewar to operate at 1.5 K. DMR receivers are located around the outside of the dewar. The instruments and mission plan have been described by Gulkis et al. (1990). Essential for the cosmological objectives are the all-sky observing strategy, periodic absolute calibrations of the instruments, high sensitivity, and extensive care to minimize potential systematic errors.

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Ganjali, Mohsen, e S. Esmail Hosseini. "Effects of frequency chirping and finite extinction ratio of optical modulators in microwave photonic IFM receivers". Optics Communications 452 (dicembre 2019): 380–86. http://dx.doi.org/10.1016/j.optcom.2019.07.070.

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48

Mireux, Olivier, Jean-Jules Brault e Renato G. Bosisio. "A Bayesian network (BN) decoder for direct-conversion microwave and millimeter-wave six-port receivers (SPRs)". Microwave and Optical Technology Letters 30, n. 1 (2001): 33–38. http://dx.doi.org/10.1002/mop.1212.

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49

Shen, Xi, Defeng David Huang, Wenxiao Wang, Andreas F. Prein e Roberto Togneri. "Retrieval of Cloud Liquid Water Using Microwave Signals from LEO Satellites: A Feasibility Study through Simulations". Atmosphere 11, n. 5 (2 maggio 2020): 460. http://dx.doi.org/10.3390/atmos11050460.

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A novel approach, using low Earth orbit (LEO) satellite microwave communication links for cloud liquid water measurements, is proposed in this paper. The feasibility of this approach is studied through simulations of the retrieval system including a LEO satellite communicating with a group of ground receivers equipped with signal-to-noise ratio (SNR) estimators, a synthetic cloud attenuation field and a tomographic retrieval algorithm. Rectangular and Gaussian basis functions are considered to define the targeted field. Simulation results suggest that the proposed least-squares based retrieval algorithm produces satisfactory outcomes for both types of basis functions. The root-mean-square error of the retrieved field is around 0.2 dB/km, with the range of the reference field as 0 to 2.35 dB/km. It is also confirmed that the partial retrieval of the cloud field is achievable when a limited number of receivers with restricted locations are available. The retrieval outcomes exhibit properties of high resolution and low error, indicating that the proposed approach has great potential for cloud observations.

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50

Brancaccio, Adriana, Giovanni Leone, Rocco Pierri e Raffaele Solimene. "Experimental Validation of a Microwave Imaging Method for Shallow Buried Target Detection by Under-Sampled Data and a Non-Cooperative Source". Sensors 21, n. 15 (29 luglio 2021): 5148. http://dx.doi.org/10.3390/s21155148.

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In microwave imaging, it is often of interest to inspect electrically large spatial regions. In these cases, data must be collected over a great deal of measurement points which entails long measurement time and/or costly, and often unfeasible, measurement configurations. In order to counteract such drawbacks, we have recently introduced a microwave imaging algorithm that looks for the scattering targets in terms of equivalent surface currents supported over a given reference plane. While this method is suited to detect shallowly buried targets, it allows one to independently process all frequency data, and hence the source and the receivers do not need to be synchronized. Moreover, spatial data can be reduced to a large extent, without any aliasing artifacts, by properly combining single-frequency reconstructions. In this paper, we validate such an approach by experimental measurements. In particular, the experimental test site consists of a sand box in open air where metallic plate targets are shallowly buried a (few cm) under the air/soil interface. The investigated region is illuminated by a fixed transmitting horn antenna, whereas the scattered field is collected over a planar measurement aperture at a fixed height from the air-sand interface. The transmitter and the receiver share only the working frequency information. Experimental results confirm the feasibility of the method.

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