WO2018198113A1 - Agencement optique pour utilisation dans un système de détection optique cohérente - Google Patents

Agencement optique pour utilisation dans un système de détection optique cohérente Download PDF

Info

Publication number
WO2018198113A1
WO2018198113A1 PCT/IL2018/050446 IL2018050446W WO2018198113A1 WO 2018198113 A1 WO2018198113 A1 WO 2018198113A1 IL 2018050446 W IL2018050446 W IL 2018050446W WO 2018198113 A1 WO2018198113 A1 WO 2018198113A1
Authority
WO
WIPO (PCT)
Prior art keywords
optical
optical sensor
arrangement
fss
sensor
Prior art date
Application number
PCT/IL2018/050446
Other languages
English (en)
Inventor
Dan Alon
Noam Cohen
Original Assignee
Oryx Vision Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Oryx Vision Ltd. filed Critical Oryx Vision Ltd.
Publication of WO2018198113A1 publication Critical patent/WO2018198113A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/481—Constructional features, e.g. arrangements of optical elements
    • G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver
    • G01S7/4812—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver transmitted and received beams following a coaxial path
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/47—Scattering, i.e. diffuse reflection
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
    • G01S17/06—Systems determining position data of a target
    • G01S17/08—Systems determining position data of a target for measuring distance only
    • G01S17/10—Systems determining position data of a target for measuring distance only using transmission of interrupted, pulse-modulated waves
    • G01S17/26—Systems determining position data of a target for measuring distance only using transmission of interrupted, pulse-modulated waves wherein the transmitted pulses use a frequency-modulated or phase-modulated carrier wave, e.g. for pulse compression of received signals

Definitions

  • the present disclosure generally relates to systems implementing coherent detection. More particularly, the present disclosure relates to systems utilizing depth sensing sensors.
  • Optical cohe ent. detection is a method of extracting information encoded as modulation of the phase and/or frequency of electromagnetic radiation in the wavelength band of visible or infrared light.
  • the received light signal is compared with a brighter standard or reference light, often called a "local oscillator” (LO) beam, by analogy with a superhetrodyne recei e .
  • LO local oscillator
  • the comparison of the two light signals is typically accomplished by combining them in a photodiode detector.
  • the two light frequencies may be similar enough that their difference or beat frequency produced by the detector is in the radio or microwave band that can be conveniently processed by electronic means .
  • FSS frequency-selective surface
  • an FSS is a type of an optical filter, in which the filtering is accomplished by virtue of the regular, periodic (usually metallic, but sometimes dielectric) pattern on the surface of the FSS.
  • multiple unit cells are utilized to obtain the desired, optical effect, unavoidably, FSS has properties which vary with incidence angle and polarization as well.
  • FSS's can be modeled as large antenna arrays, where each element in the repetitive surface acts as an antenna unit cell in the antenna array.
  • Each antenna unit cell is characterized by its mechanical properties (materials, dimensions, proximity to other unit cells, etc.) and its load impedance.
  • the load impedance is most commonly either a short (zero ohms) or an open (infinity) . These values are useful when the FSS is designed to reflect the selected frequency. If absorption is desired, matched loads are used to absorb the received energy.
  • optical sensors When optical sensors are arranged in tight and essentially repetitive arrays, they may be considered as an FSS where the detecting elements act as matched loads coupled to antenna elements, where a portion of the received energy is transferred to the load and is sensed, whereas the remaining energy is either absorbed as heat in the antenna elements or is reflected from the FSS. A portion of the reflected energy is shaped by the radiation pattern of the antenna array.
  • US 20070132645 describes an integrated sub-millimeter and infrared reflectarray that includes a reflective surface, a dielectric layer disposed on the reflective surface, and a subwavelength element array and a subwavelength element array electromagnetically coupled to the reflective surface.
  • the subwavelength element array includes (i) electrically conductive subwavelength elements on the dielectric layer, (ii) wherein the dielectric layer comprises a plurality of dielectric subwavelength elements, or (iii) the dielectric layer includes a plurality of embedded dielectric subwavelength elements.
  • US 5512901 discloses a compact radar system that includes a dielectric substrate having an upper and lower surface.
  • a ground plane is formed on the upper surface of the dielectric substrate and includes a radiating slot formed therein.
  • a radar transceiver is located below the dielectric substrate and generates transmit signals.
  • a frequency selective surface spaced above the dielectric substrate includes a radiating aperture with a plurality of uniformly spaced holes. The frequency selective surface decreases flow of electromagnetic energy from the radiating slot in one direction towards the transceiver and increases the flow of electromagnetic radiation in an opposite direction away from the transceiver.
  • US 5208603 describes a frequency selective surface (FSS) for incorporation into the outer skin of an aircraft, for transmitting electromagnetic energy in a predetermined frequency band.
  • the FSS includes three layers sandwiched together with a dielectric material. Arrays of apertures are formed in the two outer layers, which are conductive. The inner layer consists of patches of conductive material. The apertures and patches are in substantial alignment with one another.
  • a dual-band FSS, having apertures and corresponding patches in two different sizes and spacing, can be used to transmit two separate frequency bands.
  • US 5789750 discloses optical system architectures with improved spatial resolution in which the radiation useful for THz spectroscopy can be directionally coupled into and out of photoconductive structures such as dipole antennas.
  • An optical system comprises a source for emitting radiation in a frequencies' range of from 100 GHz to 20 THz, a coupling lens structure for coupling radiation emitted by that source into free space, at least one collimating optical element for collimating received coupled radiation into a beam having a frequency independent diameter and no wavefront curvature, and a detector for detecting the beam collimated by the collimating optical element.
  • the publication describes an optical system where a modified substrate lens structure is used and the collimating optical element is replaced by an optical element that focuses received coupled radiation onto a diffraction limited focal spot on or within the medium under investigation .
  • US 5164784 discloses a continuous wave Doppler LIDAR with an enhanced signal-to-noise ratio that greatly enhances its ability to determine relative fluid velocity.
  • a laser source according to this disclosure produces coherent light that is split between a reference beam and a test beam by a beam splitter. Any particle in a fluid moving relative to the CW Doppler LIDAR system that passes through the target cell causes a Doppler shift in the frequency of the coherent light reflected from the particle and reverses the rotational direction of circular polarization of the reflected beam. The light reflected from the particle is combined with the reference beam, creating a difference signal incident on a photodetector .
  • the signal power from both the local oscillator (“LO”) and transmitter (“Tx”) should be maximized. This typically may be achieved by dividing the available optical energy between the LO and the Tx, while this division is usually in equal portions .
  • the present invention seeks to solve the above drawbacks.
  • an optical arrangement for use in a coherent detection system, wherein the optical arrangement comprises a light beam generating source, an optical sensor (e.g. a detector) and an optical transmitter, and wherein the arrangement is characterized in that a) all, i.e. essentially all, of the optical energy generated by the light beam generating source is delivered to the optical sensor for use as a reference light signal, and b) at least part of the optical energy reflected from the optical sensor is delivered to the optical transmitter, for use in transmitting an optical (TX) signal .
  • TX optical
  • optical energy is delivered to the optical sensor
  • different techniques can be utilized to control the amount of optical energy that would be absorbed by the sensor. For example, by controlling the polarization of the incident bean relative to the polarization of the optical sensor, a measured amount of energy can be delivered to the sensor, allowing the remaining energy to be delivered to the optical transmitter. Such techniques are preferred particularly in cases where the total available power might be too high for the optical sensor.
  • reference light signal and "LO signal” as used herein throughout the specification and claims is used to denote bright standard or reference light, that is used for comparing it with a weaker received light signal.
  • the term “Local Oscillator” is used by analogy with superhetrodyne detection systems .
  • the information carried by the received light is encoded as an amplitude, frequency and/or phase shift from the reference signal .
  • the received signal and the reference signal may be introduced to a nonlinear signal-processing device (such as a photodiode) usually referred to as a mixing device (e.g. a multiplier or square law detector), to yield, an output signal.
  • a nonlinear signal-processing device such as a photodiode
  • a mixing device e.g. a multiplier or square law detector
  • optical transmitter as used herein through the specification and claims, is used to denote an arrangement comprising at least one optical element designed to collect optical energy reflected off the detector and shape it to illuminate a pre-defined field of view.
  • the optical energy reflected from the optical sensor and received by the optical transmitter is emitted from the optical transmitter in a predefined pattern, in order to illuminate a pre-defined field of view .
  • the optical sensor comprises a frequency selective surface (FSS) .
  • FSS frequency selective surface
  • the FSS of the optical sensor is characterized in that its implementation ensures optimal absorption of optical energy of the reference light signal that matches incident beam power and phase profiles at the sensor surface.
  • the FSS of the optical sensor is designed to enable reflecting optical energy therefrom towards the optical transmitter, in a pre-defined pattern, thereby enabling to optimize power delivery to the field of view.
  • optimization of power absorption from the received signal (RX) can be simultaneously achieved.
  • the light reflected from the FSS and received by the optical transmitter is emitted therefrom to illuminate a pre-defined field of view (FOV) in a desired FOV shape.
  • FOV field of view
  • the light is emitted from the optical transmitter in a non-uniform illumination intensity, in order to provide an increased optical energy to regions in the FOV where higher sensitivity is desirable, and/or less optical energy to regions in the FOV where less sensitivity may be tolerated.
  • the optical sensor comprises a plurality of nano rectifying antennas for detecting optical energy received thereat.
  • the plurality of nano rectifying antennas are operative at near to far IR range of frequencies (e.g. at one or more wavelengths that are within 1 - 15 ym) .
  • the optical sensor is a photodiode .
  • the light reflected from the FSS forms a pre-defined pattern that meets at least one of the following requirements:
  • a non-uniform illumination at a target the field of view For example, allowing more energy to be transmitted towards certain part(s) of the field of view, which is/are known to require higher sensitivity, and/or to allow transmitting less energy to certain parts that require lower sensitivity.
  • a field of view having a A blind spot' For example, diverting optical energy in order to eliminate a potential loss due to a mirror shadow.
  • the FSS of the optical sensor comprises an array of different FSS unit cells, where each of these unit cells has its own characteristic phase shift surface.
  • the arrangement further comprises a beam shaping means configured to operate on the reference light signal, thereby enabling to match the light beam shape with that of the optical sensor shape. For example, if the optical sensor is an array in an essentially rectangular shape, the LO beam profile can be made rectangular, thereby ensuring that the available energy is delivered to the sensor.
  • the illumination source is a gas laser.
  • the optical sensor comprises at least one array of sensing elements (e.g. array(s) of pixels ) .
  • an optical signal e.g. a modulated optical signal
  • the method comprises the steps of:
  • the optical sensor comprises a frequency selective surface (FSS) .
  • FSS frequency selective surface
  • the light beam emitted from the optical transmitter is emitted in a predefined pattern.
  • the FSS is designed to enable reflecting light therefrom towards the optical transmitter in a pre-defined pattern.
  • the method further comprising a step of shaping the light beam to match its shape with that of the FSS of the optical sensor.
  • the optical sensor comprises at least one array of sensing elements (e.g. array(s) of pixels ) .
  • FIGs . 1 - 3 demonstrate three different block diagrams of typical prior art coherent detection systems
  • FIG. 4 presents a block diagram of a coherent system construed in accordance with an embodiment of the present disclosure
  • FIG. 5 demonstrates another embodiment which illustrates a further aspect of the present invention's solution.
  • both the local oscillator (LO) and the Tx signals should be maximized.
  • this is typically achieved by using a splitter for dividing the available optical energy generated by the light source between LO and Tx . In most cases, the optical energy is equally divided between the two.
  • optical arrangement 10 construed in accordance with an embodiment provided by the present disclosure, is schematically illustrated in a block diagram presented in FIG. 4.
  • optical arrangement 10 is configured for use in an optical coherent detection system and is capable of transmitting information encoded as modulation of the phase and/or frequency (wavelength) of electromagnetic radiation in the wavelength band of visible or infrared light.
  • the system exemplified herein comprises a light source 20 which generates a light beam that optionally may be modulated with chirp modulation.
  • symbol is often used to denote the generated optical signal, characterized by its length, power, frequency and phase composition.
  • the generated symbol is transmitted towards an FSS sensor 35 of optical sensor 30.
  • the path of the transmitted light includes a mirror 40 that may be used to ensure that the light beam arrives perpendicularly to the FSS surface.
  • the optical energy of the light beam that arrives at the FSS surface is combined with that of a received optical signal by the optical sensor mixer and the combined beam is forwarded towards ADC converter 50, optionally via an amplifier 60.
  • the optical signal to be transmitted (the light beam generated by light source 20 which was chirp modulated thereat) , is forwarded to transceiver 70 which comprises combined Rx and Tx optics, and is transmitted therefrom.
  • FIG. 5 demonstrates another embodiment which provides a further view of the geometry associated with the present invention's solution.
  • available optical energy 100 which is comprised within the optical beam generated by the light source, is conveyed to the FSS sensor 121 which, in the present example is printed on the surface of sensor die 120.
  • This conveyance of optical energy is preferably done in a controlled manner in order to enable establishing a predetermined phase and spot size.
  • the desired phase and spot size are typical of a Gaussian beam waist created by lens 110 which is located along the optical path of the light beam.
  • mirror 130 may be added to ensure that the light beam is reflected from the mirror so that it arrives perpendicularly to the FSS surface.
  • the surface of FSS sensor 121 is designed to reflect the optical power and consequently to illuminate the system field of view.
  • the proposed system configuration may preferably be such that it ensures (by implementing a proper design) that the field of view and the illuminated field are essentially identical, thus eliminating losses that would otherwise occur due to the phenomenon known as parallax.
  • radiation pattern 140 is reflected from the surface of FSS sensor 121 in a way designed to match the aperture of lens 150.
  • Lens 150 is designed so as to shape the transmitted beam to illuminate the field of view 160.
  • FSS related techniques which are known in the art per se are used to shape the reflected beam, such techniques may be for example FSS, Plasmonic holography, Diffractive Optics, Metamaterials , and the like.
  • the surface of FSS sensor 121 may be a Simple' specular mirror, thereby allowing beam expansion alone to determine the shape of the reflected beam.
  • the surface of FSS sensor 121 can be made in a convex or a concave shape in order to achieve the same goal .
  • the FSS surface is designed so that the light (radiation) reflected therefrom forms a pre-defined pattern, for example in order to meet specific implementation requirements. Few examples of such possible requirements are listed hereinbelow. 1. fields of view having different shapes, such as rectangular fields designed to match a rectangular sensor array.
  • non-uniform illumination e.g. in order to allow more energy to be transmitted towards certain part(s) of the field of view, which is/are known to require higher sensitivity, and/or to allow transmitting less energy to certain parts that require lower sensitivity.
  • the FSS may comprise an array of different FSS unit cells.
  • a plurality of surface units will be used, where each of these surface units has its own characteristic phase shift surface.
  • the arrangement further comprises a beam shaping means which is operative on the LO signal before the latter is introduced to the detector die.
  • This beam shaping operation enables matching the beam profile with the sensor array shape. For example, if the sensor array is in an essentially rectangular shape, the LO beam profile can be made rectangular to ensure that all of the available energy would indeed be delivered to the sensor. Another potential use may be for example, spreading the beam energy uniformly across the optical sensor die.
  • Such a shaping operation may be done by lenses (110 in FIG. 5) or by means of reflective arrays (FSS) techniques (e.g. by replacing mirror 130 with an array of reflective surfaces) .
  • FSS reflective arrays
  • FIG. 6 presents a flow chart demonstrating a non-limiting example of a method carried out in accordance with an embodiment of the present invention for detecting an optical signal in a coherent detection system.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Electromagnetism (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

La présente invention concerne un agencement optique pour utilisation dans un système de détection cohérente et son procédé d'utilisation. L'agencement optique comprend : une source de génération de faisceau lumineux ; un capteur optique, de préférence un capteur optique qui comprend une surface sélective en fréquence (FSS) ; et un émetteur optique. L'agencement est caractérisé en ce que : a) toute l'énergie optique générée par la source de génération de faisceau lumineux est dirigée vers le capteur optique pour utilisation en tant que signal lumineux de référence au niveau de celui-ci, et b) au moins une partie de l'énergie optique réfléchie par le capteur optique est transmise vers l'émetteur optique.
PCT/IL2018/050446 2017-04-23 2018-04-22 Agencement optique pour utilisation dans un système de détection optique cohérente WO2018198113A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US201762488776P 2017-04-23 2017-04-23
US62/488,776 2017-04-23
US201762521591P 2017-06-19 2017-06-19
US62/521,591 2017-06-19

Publications (1)

Publication Number Publication Date
WO2018198113A1 true WO2018198113A1 (fr) 2018-11-01

Family

ID=63918179

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/IL2018/050448 WO2018198115A1 (fr) 2017-04-23 2018-04-22 Agencement optique et procédé pour utilisation dans le balayage continu d'un capteur optique
PCT/IL2018/050446 WO2018198113A1 (fr) 2017-04-23 2018-04-22 Agencement optique pour utilisation dans un système de détection optique cohérente

Family Applications Before (1)

Application Number Title Priority Date Filing Date
PCT/IL2018/050448 WO2018198115A1 (fr) 2017-04-23 2018-04-22 Agencement optique et procédé pour utilisation dans le balayage continu d'un capteur optique

Country Status (1)

Country Link
WO (2) WO2018198115A1 (fr)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0283222A2 (fr) * 1987-03-20 1988-09-21 Digital Optronics Corporation Système de vision à trois dimensions utilisant la détection optique cohérente
US4824251A (en) * 1987-09-25 1989-04-25 Digital Signal Corporation Optical position sensor using coherent detection and polarization preserving optical fiber
US5030004A (en) * 1988-10-14 1991-07-09 British Aerospace Public Limited Company Process and apparatus for controlling the alignment of a transmit laser beam of a coherent detection optical communications transmitter/receiver terminal
US5943133A (en) * 1996-12-04 1999-08-24 The Research Foundation Of City College Of New York System and method for performing selected optical measurements on a sample using a diffraction grating
US20090200586A1 (en) * 2008-02-08 2009-08-13 Omnivision Technologies, Inc. Backside illuminated imaging sensor with silicide light reflecting layer
US20100213375A1 (en) * 2007-06-01 2010-08-26 Johann Wolfgang Goethe-Universitat Frankfurt A.M. DEVICE AND METHOD FOR GENERATING AND DETECTING COHERENT ELECTROMAGNETIC RADIATION IN THE THz FREQUENCY RANGE
US20100277714A1 (en) * 2007-10-09 2010-11-04 Danmarks Tekniske Universitet Coherent lidar system based on a semiconductor laser and amplifier

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3930632A1 (de) * 1989-09-13 1991-03-14 Steinbichler Hans Verfahren zur direkten phasenmessung von strahlung, insbesondere lichtstrahlung, und vorrichtung zur durchfuehrung dieses verfahrens
US6075603A (en) * 1997-05-01 2000-06-13 Hughes Electronics Corporation Contactless acoustic sensing system with detector array scanning and self-calibrating
DE19929406A1 (de) * 1999-06-26 2000-12-28 Zeiss Carl Fa Zeilen-OCT als optischer Sensor für die Meß- und Medizintechnik
US7262861B1 (en) * 2004-05-24 2007-08-28 Mrl Laboratories, Llc Ultrasound single-element non-contacting inspection system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0283222A2 (fr) * 1987-03-20 1988-09-21 Digital Optronics Corporation Système de vision à trois dimensions utilisant la détection optique cohérente
US4824251A (en) * 1987-09-25 1989-04-25 Digital Signal Corporation Optical position sensor using coherent detection and polarization preserving optical fiber
US5030004A (en) * 1988-10-14 1991-07-09 British Aerospace Public Limited Company Process and apparatus for controlling the alignment of a transmit laser beam of a coherent detection optical communications transmitter/receiver terminal
US5943133A (en) * 1996-12-04 1999-08-24 The Research Foundation Of City College Of New York System and method for performing selected optical measurements on a sample using a diffraction grating
US20100213375A1 (en) * 2007-06-01 2010-08-26 Johann Wolfgang Goethe-Universitat Frankfurt A.M. DEVICE AND METHOD FOR GENERATING AND DETECTING COHERENT ELECTROMAGNETIC RADIATION IN THE THz FREQUENCY RANGE
US20100277714A1 (en) * 2007-10-09 2010-11-04 Danmarks Tekniske Universitet Coherent lidar system based on a semiconductor laser and amplifier
US20090200586A1 (en) * 2008-02-08 2009-08-13 Omnivision Technologies, Inc. Backside illuminated imaging sensor with silicide light reflecting layer

Also Published As

Publication number Publication date
WO2018198115A1 (fr) 2018-11-01

Similar Documents

Publication Publication Date Title
US7928900B2 (en) Resolution antenna array using metamaterials
Boyarsky et al. Synthetic aperture radar with dynamic metasurface antennas: a conceptual development
US6825814B2 (en) Antenna
EP0903566B1 (fr) Système d'imagerie avec des ondes submillimétriques
US5933120A (en) 2-D scanning antenna and method for the utilization thereof
CN110121656A (zh) 高分辨率3d雷达波成像设备
US20090092158A1 (en) Multi-aperture Three-Dimensional Beamforming
US20150061956A1 (en) Antenna
US20220206141A1 (en) Systems and methods for providing wide beam radar arrays
JPH09197042A (ja) ミリ波カメラ装置
US20210208253A1 (en) Optical Phased Arrays and Spherical Shift Invariant Sensors For Use In Advanced Lidar Systems
KR20170103269A (ko) 테라헤르츠파 발생 장치 및 이를 이용한 테라헤르츠 파면 제어 방법
Brandão et al. Coherent dual‐band radar system based on a unique antenna and a photonics‐based transceiver
US9559427B2 (en) Hybrid image gathering systems, satellite system, and related methods
EP0131512B1 (fr) Antenne à couverture quasi torique à deux réflecteurs
WO2018096307A1 (fr) Antenne réseau à balayage de fréquence
WO2018198113A1 (fr) Agencement optique pour utilisation dans un système de détection optique cohérente
Brandão et al. Dual-band system composed by a photonics-based radar and a focal-point/Cassegrain parabolic antenna
CN110764158B (zh) 基于反射型频控波束扫描器件的太赫兹成像系统
US20100001915A1 (en) Composite dipole array assembly
Yurduseven et al. A reconfigurable millimeter-wave spotlight metasurface aperture integrated with a frequency-diverse microwave imager for security screening
US9966647B1 (en) Optically defined antenna
WO2008109946A1 (fr) Système d'imagerie à ondes millimétriques tridimensionnel
Siragusa et al. Near field focusing circular microstrip antenna array for RFID applications
US3490021A (en) Receiving antenna apparatus compensated for antenna surface irregularities

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18790971

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 24.01.2020)

122 Ep: pct application non-entry in european phase

Ref document number: 18790971

Country of ref document: EP

Kind code of ref document: A1