Abstract: A phased array communication system and method has a plurality of phased array antenna structures disbursed throughout an aircraft in a manner to provide substantially spherical antenna coverage around the aircraft. The system includes n-element arrays and transmit/receive modules connected to respective elements forming the array. A beam forming network and antenna interface unit are included. Communication signals are converted between a satellite downlink frequency band and a communications band used by Communication, Navigation and Identification (CNI) components, known to those skilled in the art, for allowing (a) air-to-air crosslink communication; (b) satellite receive communications; and (c) air-to-ground data link communications at a satellite downlink frequency band.

Abstract: A folded microstrip antenna for a flight aggregate or aircraft can be arranged around edges of thin structural parts, such as wings, tail units or control flaps, such that its surface is identical with the structure and folding takes place at the edge of the structure. The antenna is constructed such that its characteristic impedance is much higher at the folding edge than at ends of the structural antenna away from the edge. As a result, an approximately omnidirectional characteristic can be achieved.

Abstract: A fairing for use with a phased array antenna for attenuating the transverse magnetic (TM) electric field radiated by the antenna, to thereby reduce the possibility of interference with other transceivers operating in the area of the antenna but which are not the intended recipients of a signal transmitted by the antenna. The fairing is adapted to be secured to an outer surface of a fuselage of an aircraft and to support the phased array antenna thereon. The fairing includes a plurality of concentrically arranged channels that serve to capture and ground the TM electric field as it propagates along the plane of the fairing away from the phased array antenna. Advantageously, the phased array antenna is mounted on the fairing so that the fairing also acts as a heat sink to help cool the antenna. In one preferred form the fairing is made from aluminum.

Abstract: A circularly polarized single point feed notch antenna functions on land, sea, air and space vehicles and communicates using a broad frequency range while maintaining stealth during installation on a fighter aircraft by demonstrating a low Radar Cross Section (RCS). The circularly polarized notch antenna (CPNA) employs a phase delay card polarizer to achieve circularly polarized radiation or reception. The CPNA couples non-planar conductive fins to opposing sides of a non-conducting polarizing member. The fins fashion a ninety degree longitudinal fold, tuning slots at one fin end for tuning the antenna, and bifurcated arms at an opposing end formed by a notch. The bifurcated fins possess curved edges running from a part exterior to a part interior and a recession on the fold beginning near the tuning notch(es) and running the fin length until the recession runs out when it meets the curved edge.

Abstract: A carrier structure apparatus for mounting conformal antenna elements to a non-planar mounting surface as part of an antenna array of an airborne vehicle or ground-based system also comprising a seeker section, fairing and guidance processing system. The carrier structure is a rigid and conductive apparatus that is made to conform to the geometric configuration of both the antenna element as well as the mounting surface. The conformal antenna is rigidly mounted to the carrier structure, which is in turn removably affixed to the non-planar mounting surface. With the carrier structure, each antenna element of the array may be individually tested and replaced prior to and after installation in array.

Abstract: A mount for mounting an electronic device, such as a GPS device, has an integrated antenna. In particular, the mount includes a mounting bracket and a base, to which the mounting bracket is adjustably secured. The mounting bracket has an antenna housing at an upper portion thereof, wherein the antenna housing is formed by a cavity integrally molded in the mounting bracket and a cap for positioning over the cavity. A cylindrical, helical antenna is positioned in the cavity, and the cap is releasably secured over the antenna to the periphery of the cavity. A co-axial cable connects the antenna to an electrical connector, also located on the mounting bracket. The electrical connector is adapted to connect with a corresponding electrical connector on an electronic device to which the mount is attached.

Abstract: A low cost array with wide band elements interleaved into an “egg-crate” structure. The radiating elements are flared notch radiators. Good impedance match over a wide band was achieved by feeding each element with a tapered quasi-TEM slot line, which transforms a 50-ohm input impedance to a 120-ohm radiation impedance. The radiating elements are fed by a true time delay beam-forming network to ensure that the main beam points.

Abstract: A ruggedized ultra high radio frequency antenna disposable at the rear of a hardened target penetrator warhead is provided. The antenna is usable for communicating signals from a transmitter in a deployed target penetrator warhead to a local repeater where retransmission to a more remote location can occur. The antenna includes a length-shortening and penetration abuse-resistant dielectric embedding material also supporting the subterranean signal communication to the local repeater function. Antenna radiating element fabrication from porous material such as screen wire and use of the dielectric material in a manner providing large G force tolerance and external dielectric variations are included.

Abstract: An antenna system and method of improving radio frequency isolation in such a system positioned on a hull of a vessel includes a first antenna that transmits a signal having a wavelength. The antenna system also includes a second antenna which is positioned away from the first antenna on the hull by half a perimeter of the hull offset by approximately an odd multiple of one quarter wavelength of the signal transmitted by the first antenna.

Abstract: The present invention relates to an atmospheric discharge protection arrangement in an antenna (10) arranged in communication with a hull of an aircraft (11), the antenna comprising a housing, consisting of at least a first side (14), a second side (15), a third side (16a) and a fourth side (16b), at least one of the third and fourth sides being at least transparent for electromagnetic waves. The protection arrangement is an internal protection arrangement comprising the first side (14) electrically coupled to the second side (15) through at least one antenna element (24), the first and second sides consisting of a conductive material, and that the second side being connected to hull of the aircraft (11).

Abstract: A system and method for guiding an artillery shell in flight which includes a multi-element antenna having a large central access hole therein for receiving an airfoil actuator pin, the antenna array being switched during flight, as a function of the rotation of the shell, so that the upwardly directed portion of the radiation pattern predominates over a terrestrially directed segment of the radiation pattern.

Abstract: A system for wire detection comprising a transmitter for transmitting multi-polarity waves, means for receiving waves reflected off target and means for analyzing the polarization of the reflected waves to detect linearly polarized echoes characteristic of wires and to issue a warning indicative of the presence of a wire. The wavelength of the transmitted waves is larger than the diameter of the wires to be detected. A method for wire detection comprising the following steps, for each of a plurality of angles U between 0 and 180 degrees: a. Transmit pulses of electromagnetic waves having a linear polarization at an angle U to horizontal; b. Receive echoes at the same polarization angle U; c. Prepare a map M(U, R) with the magnitude of the received echo for each angle U and each ground cell at range R.

Abstract: The invention relates to a window for use in a supersonic or hypersonic target-tracking missile, the window being transparent to electromagnetic radiation. The window consist of several window layers which support each other and which are commonly supported, wherein the materials, the thickness and the arrangement of said window layers are selected to reduce mechanical stresses due to temperature during supersonic or hypersonic flight as compared to a continuously homogeneous window. In one embodiment the window layers are fixedly interconnected with their surfaces facing each other and consist of materials having different thermal coefficients of dilatation such that, with the temperature gradient occurring in said window during supersonic or hypersonic flight, substantially identical thermal dilatations are achieved in each of said window layers.

Abstract: A compliant RF feed system (10) that provides impedance matching for VHF/AM, VHF/FM, UHF and L-band frequencies. The feed system (70) includes a feed post (14) electrically connected to an antenna element (18) at one end and a matching circuit package (22) at an opposite end, where the feed post (14) extends across a non-conductive gap (16) between the antenna element (18) and a conductive aircraft component (20). The matching package (22) includes a compressible bellows (38) mounted in the package (22), where the feed post (14) contacts the bellows (38) in a compression engagement to provide an electrical connection between the feed post (14) and a RF matching circuit (24) in the matching package (22). An impedance transformer (40) is provided in the matching package (22) to match the impedance of the bellows (38) to the matching circuit (24). The bellows (38) allows the electrical connection between the antenna element (18) and the aircraft component (20) to accommodate vibrations during aircraft operation.

Abstract: A method of reducing sidelobes of an antenna induced by a blockage in a radome covering the antenna, which includes providing at least one passive tuning element between the antenna and the blockage, and adjusting the position of the tuning element to reduce the blockage-induced sidelobes. An antenna apparatus which includes an antenna, a radome covering the antenna and including a blockage tending to induce a sidelobe in the radiation pattern of the antenna, and at least one passive tuning element between the antenna and the blockage for reducing the blocking-induced sidelobes.

Abstract: An antenna, such as may be employed for air-to-ground link hemispherical communication coverage, comprises a shaped ring focus type subreflector, that is rotationally symmetric about the boresight axis of a feed horn to which communication equipment on board an unmanned aerial vehicle is coupled. There is no main reflector associated with the shaped subreflector, so that rays from the subreflector, which emanate in a generally hemispherical pattern, are not intercepted. The generally hemispherical radiation pattern extends toward the horizon and encompasses a ground station. The subreflector is preferably shaped such that the hemispherical radiation pattern has a peak gain profile that extends from a first prescribed elevation differential slightly above the horizon to a second prescribed elevation differential slightly below the horizon.

Abstract: A collision avoidance system mountable on an aircraft for providing to the pilot of that aircraft an early warning of the presence of another nearby threat aircraft within the surrounding air space. The system operates autonomously from that aircraft and does not require the presence of any matched system on board the threat aircraft. The system includes an omni-directional L-band microwave antenna formed by a dielectric sphere cut into eight equal “orange wedge” sectors covering eight distinct beam patterns. Eight L-band microwave signals are transmitted simultaneously from all eight dielectric sectors to provide a sphere of detection around the aircraft. The sectors also act as receivers for detecting a microwave signal reflected back from the threat aircraft, and indicating means provides information to the pilot regarding the direction, closeness and rate of closure of the threat aircraft.

Abstract: An aircraft in-flight entertainment system includes an antenna, a satellite TV receiver connected to the antenna, at least one video display connected to the satellite TV receiver, and wherein the antenna is steered using received signals from the relatively wide bandwidth from at least one satellite TV transponder, such as a direct broadcast satellite (DBS) transponder. The system may include an antenna steering positioner connected to the antenna, and an antenna steering controller comprising the received signal detector for generating a received signal strength feedback signal based upon signals from the at least one satellite TV transponder. A processor may be connected to the detector for controlling the antenna steering positioner during aircraft flight and based upon the received signal strength feedback signal. The antenna steering controller may further comprise at least one inertial rate sensor, and the processor may calibrate the sensor based upon the received signal strength feedback signal.

Abstract: An aircraft mounted antenna system comprising a plurality of linear blade antenna arrays mounted on an upper portion of an aircraft fuselage. The blade arrays are symmetrically placed on the fuselage about a plane vertically bisecting the upper portion of the fuselage. The placement of the blade arrays is such that large scanning angle gain losses are minimized as the blade arrays on one side of the fuselage hand off the satellite tracking, acquisition, and communication to the blade arrays on the other side of the fuselage as the scanning angle increases.

Abstract: An antenna positioner includes a housing and a hub mounted within the housing. A substantially planar configured support plate is rotatably mounted on the hub. A substantially elongate antenna is pivotally mounted on the support plate. An elevation drive mechanism is mounted on the support plate and interconnects the antenna for pivoting the antenna a predetermined angle and adjusting elevation of the antenna. An azimuth drive mechanism is mounted on the support plate and interconnects the hub and rotates the support plate relative to the hub a predetermined arcuate distance relative to the hub and adjusts azimuth of the antenna. A controller is operatively connected to the elevation drive mechanism and the azimuth drive mechanism and controls the azimuth and elevation drive mechanisms to adjust elevation and azimuth.

Abstract: A multifunction antenna feed structure (30) that acts as a feed for a multibandwidth antenna system (22) used in connection with a modern tactical aircraft. The feed structure (30) includes a first feed (32) and a second feed (34) electrically connected to first and second feed points on an antenna element (24) at a location where the first feed (32) is impedance matched to the VHF/FM and UHF frequency bands and the second feed (34) is impedance matched to the VHF/AM frequency band. The first and second feeds (32, 34) are positioned within a flared notch (28) between the antenna element (24) and a conductive aircraft structural component (26). The feeds (32, 34) can take on different geometrical configurations, such as cylindrical feeds, cone feeds or taper feeds. The feeds are (32, 34) electrically isolated from conductive aircraft component (26) and are electrically connected to a matching network (70, 80).

Abstract: A conformal load bearing antenna structure for attachment to an aircraft having an outer skin. The conformal load bearing antenna structure comprises a top face sheet and an end fed radiating element disposed thereon. Disposed adjacent to the top face sheet is a dielectric and a structural core disposed adjacent to the dielectric. In the preferred embodiment, a bottom face sheet is disposed adjacent to the structural core and an absorber is disposed adjacent to the bottom face sheet. Accordingly, the top face sheet, the dielectric, the structural core, and the bottom face sheet are configured to provide structural strength to the aircraft when the antenna is attached to the outer skin thereof.

Abstract: An antenna reflector for a spacecraft is elastically deformable so as to be capable of changing from a folded position, when inside the spacecraft, to a deployed position, outside the spacecraft, at least partly under the action of its own elasticity. The reflector is separated into at least two parts by first opposing slot edges forming a crossing slot, so that in the folded position, the first opposing edges move with respect to each other so as to allow a protruding peripheral part of the reflector to be arranged closer to a longitudinal end of the spacecraft with damaging any portion of the reflector. In one embodiment, the two parts may be further separated by a radial slot which is arranged substantially orthogonal to the crossing slot.

Abstract: A structural endcap antenna for a vertical tail of an aircraft. The endcap antenna comprises an outer skin having an inner surface and an antenna element disposed adjacent to the inner surface of the outer skin. The antenna element is in electrical communication with an RF signal source. Disposed adjacent to the antenna element is an inner support structure electrically bonded thereto. The antenna element and the inner support structure are excited by the RF signal source and provide structural support to the endcap antenna.

Abstract: An antenna dish for reflecting signals for a first antenna operating in a first frequency band is mounted in proximity to a second antenna operating in a second frequency band separated from the first band. With the two antennas in certain relative orientations, the dish is partially or totally in the receiving and transmitting path of the second antenna. The dish is modified so that signals in the first frequency band can effectively pass through the dish. This end result is achieved by placing conductive antenna elements over the entire reflecting surface, these elements being dimensioned to efficiently radiate and receive signals in the first frequency band, thereby permitting such signals to effectively pass through the reflector dish.

Abstract: An apparatus and method for exciting an antenna with dual frequency bands which comprises feeding a first channel of the antenna with a first signal in the VHF band such that a first current is established in a first direction resulting in a first polarization, feeding a second channel of the antenna with a second signal such that a second current is established in a second direction resulting in a second polarization, and isolating characteristics of the first channel from characteristics of the second channel and the characteristics of the second channel from the characteristics of the first channel such that both the first channel and the second channel are adapted to transmit and receive energy within the same antenna structure without appreciable coupling between the first channel and the second channel.

Abstract: Apparatus which overcomes the blockage effect of an object in the path of a beam of RF energy, includes a conformal array of parasitic electrical conductor elements having a length of about .lambda./3 and which are selectively located above the surface of the object, also at a height of about .lambda./3. The parasitic conductor elements operate to duct the RF energy of the beam around the object with minimal loss in gain and effect on the beam's radiation pattern.

Abstract: An antenna for utilization in a fuse of an artillery shell is disclosed. The antenna comprises a radiator, a capacitance hat disposed at a first end of the radiator for capacitively loading the radiator and a ground plane disposed at a second end of the radiator such that the antenna is a monopole antenna. The antenna also includes a dielectric having a top surface, a bottom surface and a central longitudinal axis wherein the capacitance hat is disposed on the top surface of the dielectric and the ground plane is disposed on the bottom surface of the dielectric. A fuse utilized for detonating the explosive charge of an artillery shell is further disclosed. The fuse includes a fuse casing with the antenna of the present invention disposed within the interior cavity of the fuse casing.

Abstract: A lightning protection element is incorporated into the portion of an aircraft signal distribution system which connects an antenna to flight critical equipment. The lightning protection element rejects surge currents associated with direct lightning strikes on the antenna, or its surrounding radome, while passing communication signals without significant interference with those signals. In a preferred embodiment, the lightning protection element comprises an optical fiber isolator element. A segment of optical fiber in the isolator prevents surge currents associated with the lightning strikes from reaching the equipment while passing communications signals transmitted on the signal distribution system.

Abstract: A radar antenna system, adapted to be supported on an aircraft for surveillance, employs a nonconducting disk radome structured with aerodynamic fairing and otherwise to produce relatively low aerodynamic drag. A plurality of struts are used to secure the disk radome to the aircraft with the disk radome generally extending in a solid horizontal reference plane. A plurality of elongated, relatively low gain radiating elements are supported by a ground-plane box within the disk radome, with the radiating elements distributed across the disk radome and disposed to radiate generally in the vertical direction. An electronic system is supported within the ground-plane box, and it includes respective transmit/receive circuits which send and receive radio frequency signals to and from the radiating elements. Power cables extend through the struts to couple signals between the electronic system in the disk radome and radar system level circuitry located externally of the disk radome.

Abstract: An antenna element is provided that includes a frequency selective surface (FSS) portion on its primary radiating/receiving surface. The antenna element is conductively or capacitively coupled to an RF feed structure that can also include an FSS portion. In a preferred embodiment, the FSS antenna portion is located at least partially within the radiation pattern of a second antenna that operates in a frequency range for which the FSS is substantially transparent. In this way, signals being transferred to or from the second antenna through space can travel through the FSS antenna portion with little attenuation and/or reflection.

Abstract: A multi-beam antenna for a wireless communication network, a method of creating cells for a wireless communication network with a multi-beam antenna held aloft by an aeronautical vehicle and a wireless infrastructure. The multi-beam antenna projects: (1) a first antenna beam to create a first cell upon a generally circular first terrestrial area below the multi-beam antenna and (2) a second antenna beam to create a second cell upon a generally circular second terrestrial area below the multi-beam antenna, the first cell having a smaller radius than, and substantially concentric with, the second cell.

Abstract: A retractable forward looking radome assembly which extends from a recess in the undersurface of the aircraft is provided for housing and protecting one or more radar systems and orienting the radar systems and radome wall for adequate transmission. The retractable forward looking radome may be adapted for housing a mm-wave imaging radar system or may house multiple radar systems. Depending upon the application, different radome wall designs may be used. In one embodiment, a retractable forward looking radome is provided which extends from the nose portion of an aircraft having a highly pointed nose, such as a supersonic airliner. In another embodiment, a retractable forward looking radome is provided which extends from and retracts into a larger nose radome. In another embodiment, a retractable forward looking radome is provided which extends from and retracts into the lower fuselage of an aircraft.

Abstract: The objective of the invention is to compensate for the attenuation, in a direction (X,X), of the radiation from an antenna (5) mounted on a helicopter (1), including elements (12) which disturb the propagation of electromagnetic waves. According to the invention, at least one conducting wire (14) is fixed on the structure (1) of said helicopter, in proximity to said antenna (5), and positioned so that the electromagnetic interaction between said antenna (5) and said conducting wire (14) at least partially compensates for said attenuation of radiation.

Abstract: An array antenna is located on an upper surface of a vehicle. The array antenna is oriented at a right angle to a radio wave blocking obstacle existing in a radio wave transmission path. A diffracted wave is effectively received at the shadowed portion where a direct wave is not transmitted because of the radio wave blocking obstacle. If the antenna dimension of its longitudinal direction is larger than that of the radio wave blocking obstacle, both direct wave and diffracted wave are received and therefore the reception power decrease caused by the radio wave blocking obstacle is further reduced.

Abstract: The antenna mount is for use in mounting a GPS antenna and a differential antenna on an aircraft. The antenna mount is fixed externally of the aircraft on an outer surface of a curved rear wall of the cockpit canopy. The antenna mount comprises a shell having a top wall for mounting at least one antenna, a front wall, side walls of substantially equal length, and a rear wall. The antenna mount is sized such that electronics required by the antenna may be placed such that they are enclosed therein. The mounting bolts are provided for fixing the antenna mount to the outer surface of the rear wall of the cockpit canopy.

Abstract: A retractable sensor system (12) for an aircraft has a sensor (16) coupled to an actuation mechanism (18). The sensor (16) moves from a retracted position to an expanded position. A reinforced elastomer section (14) in an exterior surface (48) of the aircraft covers the sensor (16) and the actuation mechanism (18). The reinforced elastomer section (14) has an interior surface and an exterior surface and the sensor (16) has a portion adjacent to the interior surface. The reinforced elastomer section (14) has a flush position and an expanded position.

Abstract: Aircraft-mounted Identification Friend or Foe (IFF) antennas employ a linear array of radiator elements positioned transverse to the boresight axis. With an azimuth determination capability, but lacking elevation resolution, such antennas are subject to coning errors in determining the azimuth bearing of a target at an altitude differential. With use of a linear array (10) of multi-radiator elements (11, 12, 13), an output signal (23) having the characteristic of an amplitude which increases for off-boresight targets is provided. That signal is compared to a typical form of antenna system output signal (22), which has an amplitude which decreases for off-boresight targets. By such amplitude comparison, the angle (.beta.) to a target is determined and used to provide an azimuth correction factor (53). An apparent azimuth bearing (54) subject to coning error can then be corrected (55) to provide the true azimuth angle to a target (56).

Abstract: A fixed body wide field-of-view conformal antenna array suitable for broadband precision direction finding on missile platforms. The array is configured as multiple sub-arrays of spiral antennas that cover particular regions within the desired field-of-view of the entire array. A lower cost, more reliable and more accurate direction finding solution for missile needs is provided, primarily by the elimination of conventional radomes and antenna gimbal structures. The array can be configured to include multi-mode sensors.

Abstract: A fixed body wide field-of-view conformal antenna array suitable for broadband precision direction finding on missile platforms. The array is configured as multiple sub-arrays of spiral antennas that cover particular regions within the desired field-of-view of the entire array. A lower cost, more reliable and more accurate direction finding solution for missile needs is provided, primarily by the elimination of conventional radomes and antenna gimbal structures. The array can be configured to include multi-mode sensors.

Abstract: A fixed body wide field-of-view conformal antenna array suitable for broadband precision direction finding on missile platforms. The array is configured as multiple sub-arrays of spiral antennas that cover particular regions within the desired field-of-view of the entire array. A lower cost, more reliable and more accurate direction finding solution for missile needs is provided, primarily by the elimination of conventional radomes and antenna gimbal structures. The array can be configured to include multi-mode sensors.

Abstract: A broadband flared slot notch antenna combined with an overhead metal plate resulting in an improved front-to-back ratio and a reduced response to crossed polarized radiation. The antenna is provided by a metal layer deposited on a dielectric substrate which is etched to form a pair of symmetrical slot sections having facing edges which increasingly curve away from each other to a maximum spacing point which is the antenna aperture. A linking slot interconnects the slot sections at a feed point spaced from the aperture. High frequency electrical voltage applied at the feed point achieves launch of an electromagnetic wave from the aperture. The overhead metal plate is parallel and closely spaced above and shorted to the antenna thereby reducing radiation emissions that are not in the direction of that launched from the aperture.

Abstract: Disclosed is a combined antenna and helicopter rotor blade. The antenna has one or more electrically non-conductive rotor blades, each having an electrical conductor positioned parallel to the major axis of a respective rotor blade. An electrical connection is provided to connect the antenna to a radio for the reception or transmission of radio waves. Also disclosed is a communications system including apparatus for the transmission or reception of radio waves. Two of the electrical conductors, having angular positions nearer to a predetermined angular position are connected via the electrical connector to the radio. The remaining conductors may either be connected to the body of the helicopter or supplied with a signal out of phase compared to that supplied to the two electrical conductors.

Abstract: A low profile, compact microstrip-to-waveguide or stripline-to-waveguide transition. The end of the waveguide is terminated in a cavity backed slot defined in a groundplane formed on a dielectric substrate. The slot is excited by a microstrip or stripline conductor defined on the opposite side of the substrate. The conductor is terminated in a T-shaped junction including two opposed arms extending along the slot, each having a length equal to one-quarter wavelength at the center frequency of operation. A cavity covers the substrate on the conductor side, and is sized so that no cavity modes resonate in the frequency band of operation. The transition is matched by appropriate selection of the length of the slot and the length and position of the microstrip.

Abstract: A low profile, compact microstrip-to-waveguide transition which utilizes electromagnetic coupling instead of direct coupling. The end of the waveguide is terminated in a cavity backed slot defined in a groundplane formed on a dielectric substrate. The slot is excited by a microstrip line defined on the opposite side of the substrate, offset from the slot centerline. A cavity covers the substrate on the microstrip side, and is sized so that no cavity modes resonate in the frequency band of operation. The transition is matched by appropriate selection of the length of the slot and the length and position of the microstrip.

Abstract: A mobile receiver for satellite broadcast comprises directive antennas, a navigation unit for generating a navigation signal representing a position and an attitude of an airplane, a control unit for generating a control signal for controlling the antennas, on the basis of the navigation signal from the navigation unit and prestored information indicating a position of a broadcasting satellite, and a drive unit for driving the antennas in response to the antenna control signal from the control unit to orient the directivity of the antennas toward the broadcasting satellite.

Abstract: An array antenna especially adapted for spacecraft use includes a support frame made up of intersecting beams which form an "eggcrate" of square openings. A plurality of subarrays or radiating tiles are dimensioned to fit within the openings. Distortion of the support frame due to external forces, or due to expansion and contraction of the radiating tiles, is accommodated andor resisted by a four-point mounting arrangement for each tile. Each mounting is located on the center of the sides of the radiating tile, and the corresponding center of the side of the opening in which it fits. Each mounting consists of a thin, flexible mounting beam, extending parallel to the associated support beam, and fastened to the support beam at the ends of the mounting beam. The center of the side of the tile is fastened to the center of the flexible support beam, so expansion and contraction of the tile are compensated by bending of the flexible beam.

Abstract: An elliptic-shaped cylindrical antenna radiating element having a first side and a second side includes a first rectangular slot disposed in the first side and a second port disposed in the second side. A microstrip feed network located within the antenna radiating element radiates and receives horizontal polarized electromagnetic signals through the first slot and the second slot at a phase difference of about 180 degrees. The antenna radiating element radiates and receives horizontal polarized electromagnetic signals substantially omnidirectionally.

Abstract: A Mono-Blade Antenna is disclosed which operates over many octaves of bandwidth. Electromagnetic waveforms may be transmitted and received with multi-decade bandwidth using: a metal ground plane, a Mono-Blade Antenna element fixed above the ground plane, and a coaxial transmission line feed which is connected to the antenna element and the ground plane. The antenna element has three sections: a throat, a mouth, and a radial tip. The throat is comparatively narrow and serves as the element feed point by being connected to the center conductor of the coaxial cable. The mouth is the mid-section of the antenna element, which is the widest section of the blade. The tip of the blade is formed by an arc of approximately constant radius, which results in a low voltage standing wave ratio.

Abstract: A Bi-Blade Antenna is disclosed which will radiate and receive multi-octave electromagnetic waveforms with century bandwidth (i.e. 100 to 1) using two blade antenna elements and a coaxial transmission line feed. The blade antenna elements each have a comparatively narrow throat, a mid-section called a mouth, and a tip. The two throats are fixed in proximity to each other and are fed by the coaxial line feed. The central conductor of the feed is connected to one throat while the outer coaxial conductor is connected to the second throat. The mouth is formed by an arc of constant radius to result in a low voltage standing wave ratio of about 1.19 to 1.