Showing papers on "Feed horn published in 2007"

Information equipment with a plurality of radio communication antennas

Abstract: Information equipment according to an embodiment includes a display housing with a display unit, a first radio communication antenna disposed at an end part of the display housing, a second radio communication antenna using a frequency band adjacent to or overlapped with that of the first radio communication antenna, and a third radio communication antenna disposed at an end part between the first and the second radio communication antennas, and uses a frequency band not adjacent to nor overlapped with those of the first and the second radio communication antennas.

Phase Center Study of the Electromagnetic Band Gap Antenna: Application to Reflector Antennas

Abstract: Recent studies have shown that the electromagnetic band gap (EBG) antenna can be used to feed a reflector, especially to realize multibeam coverage with geostationary satellite. However, it is necessary to evaluate its performances in terms of aperture efficiency to compare this solution to the classical ones. Among all the parameters which contribute to the aperture efficiency, one of the most important is the phase center, which has never been determined for EBG antennas. This is the aim of this letter. After defining a simple method to calculate the phase center of the EBG antennas, the position and the frequency evolution of this parameter will be studied. Then, the performances of such a feed associated with a Side Fed Offset Cassegrain Antenna (SFOCA) will be evaluated and compared with a classical feed for reflector, a Potter horn

Recent progress in development of multiband feed horns (Review)

Abstract: This paper proposes overview of the multiband feed system for reflector-type antennas. Coaxial, multimode Potter's type structures, multiband corrugated and dielectric loaded feed horns is discussed below.

Wireless millimeter wave communication system

Abstract: A lens-based millimeter wave transceiver for use in wireless communication systems operating in the E-band spectrum consistent with the FCC rules regulating the 71-76 GHz and 81-86 GHz bands. The transceiver includes a single lens adapted for transmission of millimeter radiation to form communication beams in one band of either a band of about 71-76 GHz or a band of 81-86 GHz and for collection and focusing of millimeter wave radiation from communication beams in the other of the two bands. It includes a feed horn adapted to broadcast millimeter radiation through said single lens and to collect incoming millimeter wave radiation collected and focused by said single lens. A millimeter wave diplexer separates incoming and outgoing millimeter wave radiation.

Integrated circuit beamforming horn array

Abstract: In one embodiment, an integrated circuit horn array is provided that includes: a first substrate including a plurality of horn antennas, the horn antennas being isolated by cavities in the first substrate between the horn antennas. A second substrate supports an RF feed network that either resonantly or linearly excites the horn antennas.

A New Shaped Reflector Antenna for Wide Beam Radiation Patterns

Abstract: This paper presents a new shaped reflector antenna for wide beam azimuthal patterns and a cosecant squared elevation pattern. Elliptical strips instead of parabolic strips are used in horizontal planes of the reflector surface to achieve this purpose. Simulation and measurement results of the shaped reflector fed by a ridged horn antenna are presented.

Back-to-Back Reflector Antennas With Reduced Moment of Inertia for Spacecraft Spinning Platforms

Abstract: A back-to-back reflector antenna system with reduced moment of inertia is proposed in order to address the demanding problem of supporting large reflector antennas on spinning platforms. The configuration provides additional potential advantages, such as reducing the spinning speed by half for a given sampling rate when both back-to-back reflectors are utilized. Geometrical parameters of the reflector are determined such that the moment of inertia of the rotating system is reduced. It is shown that these back-to-back reflectors suffer from a high cross-pol level in the asymmetrical plane due to the large feed offset angle. Two different methods are explored to alleviate the high cross-pol level problem. In the first method, a sub reflector is utilized to minimize the cross-pol level by satisfying the Mizugutchi condition. In the second method, a tri-mode matched feed horn is suggested to achieve a similar result. The suppressed cross-pol level puts forward the gravitationally balanced back-to-back reflector antenna systems as a potential candidate for future spacecraft antennas on spinning platforms.

Method and apparatus for using non-linear ground penetrating radar to detect objects located in the ground

Abstract: A method and apparatus for detecting objects located underground. In one advantageous embodiment, a detection system detects objects having electrical non-linear characteristics located underground. The detection system comprises a transmitter unit, a receiver, and a processor. The transmitter transmits a plurality of pulsed radio frequency signals having a first frequency and a second frequency into a ground. The receiver monitors for a response radio frequency signal having a frequency equal to a difference between the first frequency and a second frequency, wherein the response radio frequency signal is generated by an object having the non-linear conductive characteristics in response to receiving the plurality of electromagnetic signals. The processor is connected to the transmitter unit and the receiver, wherein the processor controls an operation of the transmitter unit and the receiver, wherein the object is detected when the response radio frequency signal is detected by the receiver.

Research and design on ultra-wideband dielectric hemispheric lens loaded quad-ridged horn antenna

Abstract: Based on the ultra-wideband ridged horn antenna theory in communication system, a new quad-ridged horn antenna with a lens is described in this paper, which consists of a quad-ridged horn and a dielectric hemispheric lens. By simulation and optimization with CST MWS software which is based on the finite integration technique, a dual polarization dielectric lens loaded quad-ridged horn antenna can realize higher gain and ultra-wideband character. The result shows that in ideal state, the dielectric lens can increase the gain of quad-ridged horn antenna with 3 dB and the 15 dB gain is very important in some application. Besides, the volume of the system does not enlarge much. The simulated return loss S11 of the horn antenna system is better than -10 dB during the operating frequency band from 2 GHz to 18 GHz. Also, for its own structure of the quad-ridged horn antenna, it can realize dual polarization character as describe in this paper. The simulation results and analyses of the ultra-wideband quad-ridged horn antenna are presented.

Modular waveguide feed horn

Abstract: A modular waveguide feed horn is provided that includes an assembly having a waveguide plate section. The modular waveguide feed horn assembly also includes a feed horn section having at least one feed horn. The feed horn section is separately provided from and removably coupled to the waveguide plate section.

Stacked Microstrip-Patch Arrays as Alternative Feeds for Spaceborne Reflector Antennas

Abstract: The feasibility of using stacked microstrip-patch arrays as feeds for offset reflector antennas is investigated in this paper. It is shown that patch arrays can be used as alternatives to the conventionally used horn feeds, which tend to be bulky. In particular, patch arrays can be of interest for spacecraft applications where reduced size and light-weight feeds are highly desirable. In this paper, patch arrays were tailored to provide radiation characteristics similar to those of horn feeds by varying the element spacing and excitation. A reduction in weight was mainly realized by the planar construction of the patch arrays. A full-wave analysis of the feed array, using finite-difference time-domain (FDTD) and PO-based UCLA reflector-analysis codes, was used to test the results of the proposed feed, operating at 1.413 GHz for radiometer applications, and 1.26 GHz for radar applications. A dual-polarized and dual-frequency stacked microstrip-patch element was fabricated and tested. It was then demonstrated that a seven-element hexagonal array design seemed to be the best match to the horn feeds for a 12 m offset-reflector antenna.

A dualband coaxial dielectric-loaded feed horn

Abstract: A novel dualband hybrid-mode coaxial feed horn partially loaded by dielectric is proposed. It has a simple structure and demonstrates good electrical performance over wide frequency range within each operating frequency band, when separation between operating bands is 3:1 or more.

A Novel Technique for High-Performance Correction of Beam Aberration in Deep Space Antennas

Abstract: This letter presents a high performance technique for beam aberration correction in beam-waveguide (BWG) antennas. Beam aberration arises when high-gain ground-station antennas target spacecrafts moving not only along the antenna boresight, but also in the transversal direction. In this case, the antenna receives and transmits in slightly different directions, and, therefore a separation of the transmission and reception beams is needed. The novel algorithm has been developed in the case of European Space Agency (ESA) deep-space antenna 2, and consists in moving part of the lower beam-waveguide feed system. In particular, an ellipsoidal solid mirror is translated along three axes, and a feed horn is translated along one axis. The proposed methodology is validated by comparing its performance with two other techniques found in the literature, in terms of physical optics simulation results. It will be shown how the novel approach allows for higher beam separation, while keeping very low antenna gain degradation. Moreover, the required movements can be achieved with simpler and cheaper servo-mechanisms.

Multi-band circular polarity elliptical horn antenna

Abstract: A relatively low cost, easy to install and aesthetically pleasing multi-band, multi-port digital video broadcast from satellite (DVBS) elliptical horn antenna designed as part of a reflector antenna system to simultaneously receive satellite television broadcast signals with circular polarity on two frequency channels. This type antenna may be implemented with a single antenna feed horn with multiple feed horns that may be arranged separately or in one or more integral feed horn blocks. The antennas may be designed to achieve acceptable circular polarity performance over broad and multiple frequency bands through the use of oppositely sloped differential phase differential sections.

Cross-polar compensating feed horn and method of manufacture

Abstract: A feed horn with a horn body and a waveguide body, each with a front end and a back end, respectively. The horn body and the waveguide body coupled together, the waveguide body front end to the horn body back end. The waveguide body provided with a waveguide bore between the front end and the back end. At least one slot formed in the waveguide bore parallel to a longitudinal axis of the body bore, the at least one slot extending to the front end. The horn body provided with a horn bore between the front end and the back end. The horn body and the waveguide body formable via injection molding methods such as die casting.

A New Horn Array Feed for Parabolic Cylindrical Reflector Antenna

Abstract: A new horn array for parabolic cylindrical reflector antenna is proposed in this paper. By using the new horns, the linear array can suppress grating lobes when the element spacing is larger than one wavelength. The new array is adopted as the feed of a spatial power combining antenna. The gain of the antenna with new horn array feed is 1.2dB higher than that of the antenna with conventional pyramidal horn array feed.

Transmitter architecture based on antenna parasitic switching

Abstract: The invention is a radio transmitter that includes an antenna having at least one driven element and at least one reflector element. The driven element is electrically coupled to a radio carrier source. At least one of the driven elements or the at least one reflector element, includes at least one switch to modulate the radio carrier. Also, a secure communication system includes a radio transmitter configured to transmit a modulated signal within an information beam width. Also, a method for modulating a radio signal includes the steps of causing the transmitted carrier signal to be modulated by the modulation signal in response to switching the at least one reflector switch. Also, a method for selecting desirable antenna reflector switch combinations includes performing a mathematical simulation to determine whether the combination of reflector switch positions results in a modulated signal that can be demodulated within an information beam width.

Dual band corrugated feed horn antenna

Abstract: A dual band antenna with a corrugated feed horn comprises a waveguide and a feed horn assembly. The feed horn assembly comprises at least two portions. Two portions each have at least a cylindrical ring and a groove, in which the groove is between two cylindrical rings. By means of adjusting a depth and width of the grooves and a walls width and number of loops of the cylindrical rings of two portions causes each portion responds to different frequency band electromagnetic signal separately and thereby can be adapted to receive radio signals in at least two frequency bands electromagnetic signals. Therefore, this single antenna can be adapted to receive radio signals in two frequency bands. The antenna can effectively reduce manufacturing cost and save space.

A Metallized Plastic Feed Horn with Optimized Smooth-Walled Profile and Low Cross Polarization at 20/30 GHz

Abstract: For high volume products like a DVB-RCS terminal, manufacturing by plastic injection molding and metallization techniques are considered to be key technologies to make low cost ground terminals feasible. In this paper we report on the electrical design of a smooth-walled feed horn, where the horn profile is optimized to obtain low cross polarization both at 20 and 30 GHz. The optimized feed horn is manufactured by plastic injection molding and metallization techniques. The optimized horn has an aperture diameter of 3 8 mm, length 42.9 mm and is fed from an 11 mm diameter waveguide. The feed horn has XPD > 25 dB within the Rx-band and XPD > 32 dB within the Tx-band, and return loss is better than 25 dB in both bands. (5 pages)

Feed for Simultaneous X-Band and Ka-Band Operations on Large Aperture Antennas

Abstract: With the introduction of the Wideband Global Satcom (WGS) satellites, simultaneous operation in X-Band and in Ka-Band will be a requirement for many terminals. Overwatch Textron Systems, Ltd. is a provider of multiband feeds and has developed feed systems that operate simultaneously in X-Band and Ka-Band in transmit and receive. The feed system has also been designed to operate with multiple carriers in a Low passive intermodulation product environment. These feed systems have been deployed in multiple configurations including Teleport class antennas, shipboard antennas, and flyaway antennas. The feed system is designed using Overwatch's patented multiband feed technology and is easily adapted to operate with existing reflector systems. This feed system is very useful for terminals that are difficult to access or where real estate does not allow the installation of multiple antennas. This paper details the efforts of adapting this feed technology to Large Aperture antennas. The paper provides details on the original proof of concept antenna as well as current enhancements being made to improve the capabilities of the feed and antenna systems. One of these enhancements is the addition of pseudo-monopulse tracking to the feed system.

Electronically scanned antenna

Abstract: An electronically scanned antenna may include a plurality of space-fed, contiguous subarrays arranged in an annular region, each subarray including an inner set of radiating elements facing inwardly, an outer-facing set of radiating elements, and a feed system for illuminating the inner set of radiating elements. A plurality of RF amplifiers are coupled through a commutation switch matrix to selected ones of the subarray feed horn systems to illuminate a desired sector with RF energy.

Light weight radar antenna for tracking

Abstract: A polarization conversion type radar antenna for tracking is provided to be promptly driven with a low capacity motor by realizing a main reflecting plate, a sub reflecting plate, a feed horn, and a box in a structure of attaching a metal coated FRP(Fiber Reinforced Plastics) plate to a honeycomb cell. A polarization conversion type radar antenna for tracking includes a main reflecting plate, a sub reflecting plate, a reflecting plate frame, four feed horns(140-1 to 140-4), a box, and a mechanical structure. After converting liner polarized light into circular polarized light, the main reflecting plate converts the circular polarized light into another linear polarized light. The main reflecting plate is formed in a dual structure reflecting plate in which a parabola type carbon and an FRP are attached on both sides of a honeycomb foil metal or an insulating material. A cassegrain or deformed FRP plate is attached to both side of a honeycomb insulating material to transmit one of vertical polarization and horizontal polarization and to reflect the other to the main reflecting plate. The reflecting plate frame removes side lobes between the main reflecting plate and the sub reflecting plate. The box has a mono pulse coupler in a case of the dual structure reflection plate. The mechanical structure supports an antenna plate composed of the main reflecting plate and the sub reflecting plate to drive the antenna up/down and right/left.

Miniaturization technique of COBRA lens horn using a modified lens with curved surfaces

Abstract: In this paper, miniaturization technique using modified lens with curved surfaces is introduced to avoid enlargement of COBRA (coaxial beam rotating antenna) horn for high power electromagnetic applications. By using this technique, the length of horn antenna of 2700 mm can be reduced as 600 mm without reduction of gain. The designed antenna applied this technique has gain of 27.80 dBi and circular polarization at boresight.

UWB Multipath Simulator based on TEM Horn Antenna

Abstract: Most of the existing UWB models are extensions of narrowband models. These models suffer from limitations because UWB multipath propagation is frequency and antenna dependent. In this paper, a directional simulator based on TEM horn antenna is developed. This simulator illustrates the spatial impact on the received multipath profiles. Several deterministic scenarios are simulated to examine the antenna impact on receiver design and positioning accuracy.

Scanned antenna system

Abstract: The invention comprises a feed horn (10) illuminating a circular flat panel (12) formed from a high impedance surface structure. By controlling the resonant frequencies of the individual elements of the array, a controlled phase shift profile is applied across the surface of the panel to an incident phase front spherically spreading from the feed antenna so as to reflect that wavefront in a particular direction or impose a certain desired beam shape. The principles are reciprocal so a receiving system can also be achieved or indeed a simultaneous transmit and receive operation can be supported. The phase controlled reflecting plate advantageously performs focussing to the feed and beam scanning or beam shaping. This concept of feed to a phased reflector plate allows the power distribution to be implemented in free space. In addition, the active component at each array element affecting the resonant frequency is a single varactor tuning diode per element with negligible power dissipation since it operates in reverse bias or a MeMs switch network. A further embodiment is described comprising a transmissive panel with phase shifting elements implemented in MeMs technology coupled to each element of the array. Calibration techniques are described that correct for non-systematic errors in the phase shifts on reflection which would corrupt the beam shape and pointing direction in a practical environment. These can be performed repeatedly, interleaved with the radar or communications waveforms passing through the antenna.

Design of a shaped double-shell lens feed for a quasi-optical reflector system

Abstract: This paper proposes a new shaped double-material lens for this objective and presents its design and performance when integrated into the reflector system. A parabolic reflector is used to prove the lens concept. Reflector optimization is out of the scope of this paper. Experimental results are presented for a fabricated scaled lens prototype at 62.5 GHz.

Design of a Simultaneous Center-Fed X/Ka-Band SATCOM Reflector Antenna with Replacable C-Band Option

Abstract: A 1.5m tri-band (C-, X- and Ka-band) center-fed SAT-COM terminal has been designed for shipboard applications. The terminal has two independent replaceable feeds; C-band and simultaneous X/Ka-band. Offset prime-focus and dual-reflector designs are optimum from a performance standpoint for a reflector of this electrical size, however the scarcity of real estate and other mechanical considerations on shipboard drives the design to a center-fed type. Of the available center-fed reflector types, a shaped ring-focus configuration was chosen since the ring-focus reflector has several advantages over Cassegrain/Gregorian types for reflectors in this electrical size range. The reflector antenna shape is derived numerically utilizing GO shaping techniques while the feeds are designed using the BOR MoM and PO methods. The resulting antenna has been constructed and tested, and results are presented.

Unique attenuation characteristics of ku-band Lune-Q antenna for Satellite retransmission of terrestrial digital broadcasting signal

Abstract: This paper deals with the unique low rain attenuation characteristics of the Lune-Q antenna, which is used in the satellite retransmission system for terrestrial digital broadcasting CTV signal by using the 14/12 GHz band transponder. To achieve the optimum design of the satellite retransmission system of terrestrial CTV signal, propagation experiments to determine the propagation characteristics and confirm the satellite digital broadcasting CTV transmissions service quality confirmation were carried out in 2006, between the JSAT Yokohama Satellite supervisory and control station (JSAT-ES) and Hokkaido Institute of Technology (HIT) earth-station (HIT-ES). During the propagation experiments, it was found that the Lune-Q antenna rain attenuation characteristics are superior to those of the conventional parabolic antenna, i.e., small rain attenuation values. The rain attenuation values of conventional parabolic antenna and the Lune-Q antenna were compared, for the period from April to October 2006. It can be observed that rain attenuation values of the Lune-Q antenna were about 1/10 times lower. The small rain attenuation characteristics are considered to originate due to reasons such as multi-path reception by the Lune-Q lens characteristics, the feed horn position, and polarization effects, etc.

Satellite broadcast receiving converter and satellite broadcast receiving antenna

Abstract: PROBLEM TO BE SOLVED: To provide a satellite broadcast receiving converter capable of heating a feed horn by incorporating a heater and to provide a satellite broadcast receiving antenna provided with the satellite broadcast receiving converter. SOLUTION: The heater 21 is installed on an inner wall face of a chassis 16 of the converter 13 integrated with the feed horn 12 via a waveguide 15. The heat from the heater 21 is delivered to the chassis 16, the waveguide 15, and the feed horn 12 in this order to melt snow and ice deposited on respective outer surfaces of the feed horn 12, the waveguide 15, and the chassis 16. COPYRIGHT: (C)2007,JPO&INPIT