Abstract: A reflector 38 includes a mirrored surface 48 and a frequency selective surface 46. The frequency selective surface 46 is arranged to reflect radiation of a first frequency band 52 and allow radiation of a second frequency band 50 to pass. The mirrored surface 48 is arranged to reflect radiation of the second frequency band 50. In this manner, the focal power for radiation of the first frequency band 52 is independent to the focal power for radiation of the second frequency band 50. Accordingly, the design of optical components associated with the second frequency band 50 can be undertaken independently of those associated with the first frequency band 52 so as to achieve the optimised focusing for each frequency band.

Abstract: A substrate integrated waveguide (10) comprises a top conductive layer (14) and a bottom conductive layer (15) provided on either sides a substrate (11). At least one wall (12, 13) of conductive material is provided in the substrate (11) to define, together with the top and bottom layers (14, 15), the waveguide. The at least one wall (12, 13) comprise a multitude of thin conductive wires densely arranged close to each other in the substrate (11) and having respective short ends connected to the top and bottom layers (14, 15). The high number of wires per surface unit in the wall (12, 13) effectively prevent significant amount of power leakage through the wall (12, 13) during operation of the substrate integrated waveguide (10).

Abstract: An improved waveguide feed includes a ridged waveguide section and a feed section. The ridged waveguide section includes a wall structure and spaced-apart opposing ridges disposed on an internal surface of the wall structure, with the spaced-apart opposing ridges extending along a major axis of the wall structure. The feed section is coupled to the ridged waveguide section, and includes an extension of only a portion of the wall structure of the ridged waveguide section, and an extension of the spaced-apart opposing ridges disposed on an internal surface of the extended wall structure of the feed section.

Abstract: Systems and methods for a dual polarization feed are provided. In at least one embodiment, a system comprises a polarization transition waveguide that comprises a first waveguide transmission line; an electrical transmission line, wherein a first electromagnetic signal propagating through the first waveguide transmission line propagates between the first waveguide transmission line and the electrical transmission line; and a dipole radiator coupled to the electrical transmission line, wherein the dipole radiator radiates the first electromagnetic signal in an orthogonal polarization to the polarization of the first electromagnetic signal when the first electromagnetic signal propagates in the first waveguide transmission line.

Abstract: A mobile wireless communications device may include a portable housing, a circuit board carried by the portable housing, a wireless communications circuit carried by the circuit board, and an audio circuit carried by the circuit board. The device may further include an antenna assembly including an antenna carrier frame coupled to the circuit board and defining a cavity therein, and at least one antenna element carried on the carrier frame and coupled to the wireless communications circuit. The device may also include an audio output transducer carried within the cavity of the antenna carrier frame and coupled to the audio circuit.

Abstract: A universal joint comprising a pair of circular waveguide ball-joints and a slip-joint allows for simultaneous 3-axis rotation and 3-dimensional translation between an antenna and a stationary source. As such, the universal joint does not have to be physically aligned with the azimuth, and elevation, rotation axis of the antenna and mounted on the gimbal support, greatly simplifying the antenna steering mechanism. The universal joint allows the antenna to be mass-balanced in relation to the azimuth and elevation axis without adding any additional counter weights, thus reducing the size and power requirements of the azimuth and elevation rotation drive systems. Additional ball-joints may be provided to increase the allowed range of motion of the antenna.

Abstract: A feed network may include a cylindrical common waveguide terminating in a common port and an orthomode transducer having a first port for coupling a first linearly polarized mode to the cylindrical common waveguide and a second port for coupling a second linearly polarized mode to the cylindrical common waveguide, the second linearly polarized mode orthogonal to the first linearly polarized mode. A filter-polarizer element may be disposed within the cylindrical common waveguide. The filter-polarizer element may be rotatable about an axis of the cylindrical common waveguide. The filter-polarizer element may be configured to cause a predetermined relative phase shift between a first signal and a second signal propagating in the cylindrical common waveguide. The filter-polarizer element may be further configured to suppress propagation of at least one undesired mode in the cylindrical common waveguide.

Abstract: Structures and methods for a tunable waveguide radiating element are disclosed. The waveguide radiating element comprises a rectangular tube, which includes partially filled dielectric slabs that are disposed on parallel planes and incident on a lower edge of the element's mouth. The faces of each slab are engraved with a number of concentric SRR squares that present a gap on one of its sides. The distance between any two consecutive slabs may vary. The gaps of the outmost square may be arranged in such a way that, on the facing sides of two adjacent slabs, the gaps are rotated with respect to each other.

Abstract: A combination conductor-antenna apparatus is provided comprising a surface that defines a passage for use as a receptor for a second conductor and for use as a waveguide. The surface is at least partially formed of an electrically conductive material, thus allowing the apparatus to serve as a medium by which an electrical signal can be transferred from a second conductor. Disposed within the passage is a pickup element for sensing and/or injecting electromagnetic energy in the passage, thus allowing the apparatus to serve as a medium for wireless communications.

Abstract: A dual polarized waveguide slot array includes a first waveguide and a second waveguide. The first waveguide includes major and minor cross-sectional axes and extends along a common longitudinal axis. The first waveguide further includes a plurality of slots disposed thereon for radiating or receiving signals of a first polarization. The second waveguide is coupled to the first waveguide, extending along the common longitudinal axis and having major and minor cross-sectional axes. The major cross-sectional axis of the second waveguide oriented substantially orthogonally to the cross-sectional axis of the first waveguide, and the second waveguide includes a plurality of slots disposed thereon for radiating or receiving signals of a second polarization substantially orthogonal to the first polarization.

Abstract: An antenna array provided with two frames which form waveguides. Each frame includes a plate portion and frame portion. The plate portion includes grooves laid out next to one another. Each groove has an open end and a closed end. The frame portion is arranged adjacent to the plate portion. The frame portion has an opening that opens in a direction perpendicular to a direction in which the grooves extend and a direction in which the grooves are laid out. A dielectric substrate is held between the two frames. The dielectric substrate includes an array of feeders and electronic circuits, each circuit having a discrete active element. The circuits are exposed from the opening of either one of the frames. The frames are superimposed with the dielectric substrate so that the grooves form the waveguides. Each circuit is electromagnetically connected to a corresponding one of the waveguides.

Abstract: Provided is a wide band antenna having ultra-wide band and high performance at a low cost. An antenna element constituting a part of an opening cross section structure of a double cylinder ridge waveguide is spread on a plane. The antenna element has a ridge element portion (21) for adjusting antenna characteristic corresponding to a ridge portion and a radiation element portion (22) for electromagnetic wave radiation. Substantially at a leading end portion of the ridge element portion (21), a feeder terminal (24) is formed. Ground portions (23a and 23b) are maintained at a ground potential and the feeder terminal (24) is guided to an outside as a coplanar waveguide.

Abstract: The subject disclosure relates to solar energy collection and use in communications systems and to enhancements thereof. In an aspect, dual function antennas are disclosed that can simultaneously function as an antenna and as a solar energy collection system. In further aspects, disclosed embodiments can focus incident solar radiation to increase output voltage of conventional solar cells. Measured and simulated results demonstrate various aspects of the subject disclosure.

Abstract: An antenna comprising a radiator which is configured to radiate electromagnetic wave inside of an antenna housing, and at least one dielectric which is configured to be contributory to directivity angle of the electromagnetic wave in the vertical direction, wherein the at least one dielectric is directly attached to the antenna housing ahead of the radiator.

Abstract: In accordance with various aspects of the present invention, a method and system for electro-mechanical polarization switching in an antenna system is presented. The antenna system may comprise an integrated waveguide in a transceiver housing, where the waveguide has at least four channels. In an exemplary embodiment, a sliding switch is incorporated into the waveguide. The sliding switch is configured to switch the polarization of the antenna system by physically realigning the waveguide channels. The sliding switch may be electro-magnetically controlled. Furthermore, the polarization switching may be performed to assist in load balancing for a particular frequency and/or polarization combination.

Abstract: An antenna may be formed from conductive regions that define a gap that is bridged by shunt inductors. The inductors may have equal inductances and may be located equidistant from each other to form a scatter-type antenna structure. The inductors may also have unequal inductances and may be located along the length of the gap with unequal inductor-to-inductor spacings, thereby creating a decreasing shunt inductance at increasing distances from a feed for the antenna. This type of antenna structure functions as a horn-type antenna. One or more scatter-type antenna structures may be cascaded to form a multiband antenna. Antenna gaps may be formed in conductive device housings.

Abstract: A wide beam radio frequency (RF) antenna includes a waveguide and one or more electrically conductive protrusions. The waveguide has at least one electrically conductive interior wall surface, a boresight defined by a longitudinal axis, and an aperture plane, transverse to the longitudinal axis, disposed at a distal end of the waveguide. A first proximal portion of each protrusion is electrically coupled to the electrically conductive interior wall surface, a distal portion of the protrusion being outside the aperture plane.

Abstract: Sequencing circuitry for a ferroelectric RFID circuit includes an input node for receiving an external voltage, a bandgap circuit coupled to the input node, a bandgap ready circuit coupled to the bandgap circuit, a slew filter having an input coupled to the input node and to the bandgap ready circuit, a filter capacitor coupled to an output of the slew filter, and an LDO regulator having an input coupled to the output of the slew filter having a plurality of regulated voltages for use in a memory portion, a digital circuit portion, and for generating a reset signal. The sequencing circuitry further includes delay circuits for introducing a controlled delay between operational modes, POR cells for monitoring power supply voltages, and a digital state machine for monitoring internal nodes to control a shut-down pulse generator.

Abstract: Implementations for exciting two or more modes via modal decomposition of a pulse by a wave launcher are generally disclosed.

Abstract: Antenna arrays providing high gain during wireless communications are highly desirable for many applications including, but not limited to, multiple-in multiple-out (MIMO) streams and video transmissions. Optimized antenna arrays should also ensure ease of manufacture, thereby enhancing commercial viability. Circular antenna arrays including horn antennas or Yagi antennas are described, each circular antenna array ensuring ease of manufacture.

Abstract: A mobile wireless communications device may include a portable housing, a circuit board carried by the portable housing, a wireless communications circuit carried by the circuit board, and an audio circuit carried by the circuit board. The mobile wireless communications device may further include an antenna assembly including an antenna carrier frame coupled to the circuit board and defining a cavity therein, and an antenna element carried on the antenna carrier frame and having a plurality of spaced apart signal feed points coupled to the wireless communications circuit. In addition, an audio transducer may be carried within the cavity of the antenna carrier frame and coupled to the audio circuit.

Abstract: An antenna device includes a housing having a plurality of printed circuit board (PCB) panels connected together with folded joints therebetween to define a polyhedral shape having a first open end. Each of the PCB panels includes a dielectric substrate and an electrically conductive layer thereon inside of the housing. Wireless communication circuitry is mounted on at least one of the plurality of PCB panels outside the housing, and an antenna feed is connected to the wireless communication circuitry adjacent a second end opposite the first open end of the housing.

Abstract: Presently disclosed is an antenna system having an array of ridged waveguide Vivaldi radiator (RWVR) antenna elements fed through a corporate network of suspended air striplines (SAS). The SAS transfers the electromagnetic energy to the radiating element via the ridged waveguide coupler. The Vivaldi radiator matches the output impedance of the ridged waveguide coupler/SAS to the impedance of the surrounding medium. Because the coupling method and the radiating elements are wideband mediums, this antenna array is capable of wideband operation. The physical dimensions of the resulting array are also not as sensitive to its electrical performance as other antenna designs since the bandwidth is quite large, reducing the occurrence of an out-of-specification antenna due to manufacturing tolerance build-up. This also reduces the complexity of the manufacturing process, which in turn lowers cost.

Abstract: The antenna assembly includes first and second adjacent antenna elements each having a tapered or conical antenna body with a base and an apex opposite the base. An elongated or cylindrical antenna body extends from the base of the conical antenna body, and includes a plurality of adjacent elongated or cylindrical antenna body portions, and a respective dielectric member separating adjacent cylindrical antenna body portions. Each of the first and second adjacent antenna elements are aligned along a common longitudinal axis with respective apexes in opposing relation to define a dipole antenna. Increased radiation pattern bandwidth and satisfactory pattern on the horizon may be achieved in such a biconical-type antenna.

Abstract: A method of measuring the permittivity and/or conductivity of a multiphase fluid flowing through a conduit is provided. The method includes the steps of measuring the signal from a first electromagnetic transmitter to a first electromagnetic receiver separated by a first distance, measuring the signal from the first electromagnetic transmitter to a second electromagnetic receiver separated by a second distance, measuring the signal from a second electromagnetic transmitter to the first electromagnetic receiver separated by a distance substantially equal to the second distance, measuring the signal from the second electromagnetic transmitter to the second electromagnetic receiver separated by a distance substantially equal to the first distance, and wherein the first and second distances are substantially different.

Abstract: An antenna system comprising a first antenna corresponding to a horn antenna, a second antenna corresponding to a horn antenna disposed such that the E-plane of the second antenna is co-planar with the E-plane of the first antenna an such that an aperture of the first antenna and an aperture of the second antenna are substantially in a common plane; and a third antenna corresponding to a horn antenna disposed such that the E-plane of the third antenna is substantially co-planar with the E-plane of the first antenna and such that an aperture of said third antenna is substantially in the same plane as the aperture of the first and second antennas and wherein the second and third antennas are canted toward each other.

Abstract: A dual-band antenna system configured to transmit and/or receive microwave beams over two or more frequency bands with substantially similar beam widths and substantially similar sidelobe levels is disclosed. The antenna system includes at least one reflector and at least one feed horn, the horn configured to provide a first efficiency over a first frequency band and lower efficiencies over one or more second frequency bands. The horn includes a substantially conical wall having an internal surface with a variable slope. The internal surface includes one or more slope discontinuities, wherein the slope discontinuities are configured to generate primarily TE1,m modes within the first frequency band and within the second frequency bands and generate TM1,n modes substantially only within the second frequency bands.

Abstract: A radiating element is provided, for example for array antenna, having stacked resonant cavities of Pérot-Fabry type, of compact structure, a lower cavity being fed by excitation means, the radiating element being characterized in that corrugations are formed substantially below a first earth plane delimiting in its lower part the upper resonant cavity. A radiating element structure of improved compactness is also proposed, whose upper cavity is surmounted by a polarizing radome.

Abstract: Methods and systems for converting RF power to DC power utilizing a leaky wave antenna (LWA) are disclosed and may include receiving RF wireless signals utilizing one or more LWAs in a wireless device, and generating one or more DC voltages from the received RF signals utilizing cascaded rectifier cells. A resonant frequency of the LWAs may be configured utilizing micro-electro-mechanical systems (MEMS) deflection. The LWAs may be configured to receive the RF signals from a desired direction. The LWAs may comprise microstrip or coplanar waveguides, wherein a cavity height of the LWAs is dependent on a spacing between conductive lines in the waveguides. The LWAs may be integrated in one or more integrated circuits, integrated circuit packages, and/or printed circuit boards. The packages may be affixed to one or more printed circuit boards and the integrated circuits may be flip-chip-bonded to the packages.

Abstract: A wireless communications device may include wireless communications circuitry and a waveguide transducer coupled to the wireless communications circuitry. The waveguide transducer may include a loop electrical conductor having a plurality of spaced apart gaps therein defining a plurality of respective spaced apart coupling points. The waveguide transducer may also include a feed assembly that may include at least one waveguide feed, and a feed network coupled between the at least one waveguide feed and the plurality of coupling points. The waveguide transducer may further include a waveguide surrounding the loop electrical conductor and extending outwardly therefrom. The waveguide may include a tubular body having an open end and an opposing closed end carrying the loop electrical conductor.

Abstract: An aperture of an antenna for a radar system comprises a first waveguide comprising a first protrusion and a second protrusion, each protrusion extending longitudinally along one side of the first waveguide. The aperture further comprises a second waveguide comprising a third protrusion and a fourth protrusion, each protrusion extending longitudinally along one side of the second waveguide. The first and third protrusions and second and fourth protrusions adjoin to form a radio frequency choke at least partially suppressing cross polarization of radio frequencies between the first and second waveguides.

Abstract: A leaky cavity resonator that includes a waveguide, the waveguide being filled with a dielectric material, and at least two complementary split ring resonators (CSRRs), the CSRRs residing inside the waveguide parallel to each other placed symmetrically both radially and in height, a leaky resonant cavity being formed between the at least two CSRRs and a wall of the waveguide. A frequency band of the leaky cavity resonator is adjustable by varying a distance w between at least one outside perimeter of at least one CSRR and an interior wall of the waveguide. A frequency band of the leaky cavity resonator is also adjustable by varying a size of the leaky resonant cavity. The at least two CSRRs each have at least one stub connecting to a wall of the waveguide. A frequency band of the leaky cavity resonator is also adjustable by varying a size of the stubs.

Abstract: A method and apparatus comprising a dielectric structure and a plurality of conductive segments. The dielectric structure is configured for placement in a waveguide. The plurality of conductive segments is located within the dielectric structure. Each of the plurality of conductive segments is configured to reduce a passing of a number of frequencies of electromagnetic signals traveling through the dielectric structure.

Abstract: Multi-band antennas for simultaneously communicating linear polarity low-band signals and circular polarity high-band signals via a single antenna horn structure. The antennas horn structures have circular and oblong cross-sections. Strategic location and orientation of low-band and high-band ports with respect to internal ridges in transition sections and the major and minor axes of the oblong horn allows the antenna to simultaneously manipulate the high-band circular polarity signal without affecting the linear polarity low-band signals. The oblong horn shape and ridges may apply additive or oppositely sloped differential phase shifts to the linear components of the circular polarity high-band signal. For the horns with circular cross-section, the internal ridges may apply additive or oppositely sloped differential phase shifts to polarize the circular polarity high band signals without assistance from the internal shape of the horn.

Abstract: Aspects of a method and system for frequency-shift based PCB-to-PCB communications may include, in a PCB comprising one or more receivers and one or more transmitters, adjusting one or more modulation frequencies and utilizing the adjusted modulation frequencies to generate transmit signals by the one or more transmitters based on received and/or generated modulation control information. One or more demodulation frequencies may be adjusted and utilized to generate intermediate frequency signals by the one or more receivers based on received and/or generated demodulation control information. The modulation control information and the demodulation control information may be received via a communication device comprising the PCB. The modulation control information and demodulation control information may be received on a link operating in a frequency band different from the transmit frequencies and the receive frequencies.

Abstract: Radio frequency signals having a plurality of frequency ranges are received and coupled to a plurality of transmission lines, each of the plurality of transmission lines being formed in a corresponding plurality of generally parallel planes. Circuitry is formed for each of the plurality of transmission lines to define substantially low impedances for all of the plurality of frequency ranges except for a frequency range or ranges to be carried by the corresponding transmission line. Signals are coupled to the plurality of transmission lines so that signals with the plurality of frequency ranges are received and distributed with substantially decreased reflection and substantially high impedance matching by the plurality of transmission lines.

Abstract: An antenna for broadband satellite communication including an array of primary horn antenna elements which are connected to one another by a waveguide feed network.

Abstract: An antenna includes a waveguide having an aperture at a first end and a conducting component at a second end, the conducting component shorting the waveguide and a first set of two orthogonal dipoles, fed in quadrature, the orthogonal dipoles located near the aperture of the waveguide operating close to its dominant mode cut off frequency.

Abstract: A waveguide antenna for a radar antenna array, particularly for use in motor vehicles, includes a metal waveguide extending in an x direction and having a longitudinal axis, which, for the propagation of a radar wave of a first mode in the x direction, delimits an inner space, wherein in order to specifically convert the first mode to a second mode of the radar wave which is different from the first mode and to couple the second mode out of the waveguide, a plurality of structural elements arranged in the x direction are provided which extend into the inner space and wherein adjacent structural elements have a distance which is larger than half a waveguide wavelength of the radar wave of the first mode or larger than half a free-space wavelength, depending on which of the two wavelengths is smaller.

Abstract: An RF (radio frequency) combiner utilizes RF filtering cavities and transmission paths incorporated into an RF impervious material. This allows traditional stand-alone multiplexers to be integrated into a single device without using signal loss-inducing cables and connections between the multiplexers. The simplicity of the RF combiner allows for RF filters to be milled out of the same RF impervious material without requiring an external RF connection and avoids a cascading of multiple RF filters. In one instance, the RF combiner is employed with two BTS (base transceiver stations) to allow the sharing of antennas without the power losses associated with traditional cascading duplexers.

Abstract: Processes and systems for radiating electromagnetic energy from an open-ended coaxial cavity are described herein. An antenna assembly includes an open-ended coaxial radiator. The coaxial assembly includes an inner electrically conducting surface and an outer conductive surface spaced apart from and opposing the inner electrically surface. More than one radially aligned electromagnetic coupling modules are positioned at least partially within the coaxial waveguide along different rotation angles. Each of the different electromagnetic coupling modules samples a local electric field, amplifies the sampled field, and alters a phase of at least one of the amplified fields. The amplified, phase-adjusted coaxial fields are radiated from an open end of the coaxial cavity.

Abstract: A transmitting device for electromagnetic radiation includes a waveguide having an input for coupling an electromagnetic wave into the waveguide, and multiple openings in the waveguide for emitting the electromagnetic wave. A controllable closure element is provided for selectively closing at least one of the openings with respect to the electromagnetic radiation.

Abstract: A leaky travelling wave array of optical elements provide a solar wavelength rectenna.

Abstract: Methods and systems for a smart antenna utilizing leaky wave antennas (LWAs) are disclosed and may include a programmable polarization antenna including one or more pairs of LWAs configured along different axes. One or more pairs of leaky wave antennas may be configured to adjust polarization and/or polarity of one or more RF signals communicated by the programmable polarization antenna. RF signals may be communicated via the configured programmable polarization antenna utilizing the configured one or more pairs of the leaky wave antennas. A resonant frequency of the LWAs may be configured utilizing micro-electro-mechanical systems (MEMS) deflection. The polarization and/or polarity may be configured utilizing switched phase modules. The LWAs may include microstrip or coplanar waveguides, wherein a cavity height of the LWAs is dependent on spacing between conductive lines in the waveguides. The LWAs may be integrated in one or more integrated circuits, packages, and/or printed circuit boards.

Abstract: A communications system including an antenna array and electronics assembly that may be mounted on and in a vehicle. The communication system may generally comprise an external subassembly that is mounted on an exterior surface of the vehicle, and an internal subassembly that is located within the vehicle, the external and internal subassemblies being communicatively coupled to one another. The external subassembly may comprise the antenna array as well as mounting equipment and steering actuators to move the antenna array in azimuth, elevation and polarization (for example, to track a satellite or other signal source). The internal subassembly may comprise most of the electronics associated with the communication system.

Abstract: An antenna apparatus can reduce gaps between laminated plates with a simple structure, and can be produced at low cost and in a small size, while ensuring reliability over a long period of time. The apparatus includes a base having a base transmission line portion, a laminated body that is composed of laminated plates placed on the base and has laminated body transmission line portions in communication with the base transmission line portion, and an antenna main body placed on the laminated body for emitting or receiving electromagnetic waves, wherein the base, the laminated plates and the antenna element plate are coupled with one another through surface to surface contact. The antenna main body has a curved plate formed of an arc-shaped elastic member protruding toward the base in a state before assembly, and the curved plate has an elastic force contributing to the coupling through surface to surface contact.

Abstract: The present invention provides a semiconductor device which is formed at low cost and has a great versatility, a manufacturing method thereof, and further a semiconductor device with an improved yield, and a manufacturing method thereof. A structure, which has a base including a plurality of depressions having different shapes or sizes, and a plurality of IC chips which are disposed in the depressions and which fit the depressions, is formed. A semiconductor device which selectively includes a function in accordance with an application, by using the base including the plurality of depressions and the IC chips which fit the depressions, can be manufactured at low cost.

Abstract: A probe and an antenna, more particularly, a probe and antenna using a waveguide, which reduces the multiple reflection of electromagnetic waves. The probe includes: and the antenna each include a waveguide and a resonance unit is entirely or partially disposed in the inside of the waveguide, and comprising the resonance unit including a conductor.

Abstract: The antenna may include a planar reflector having a plurality of loop electrical conductors defining an array of parasitically drivable antenna elements, and a circularly polarized antenna feed spaced from the planar reflector to parasitically drive the array of parasitically drivable antenna elements and impart a traveling wave current distribution therein. The antenna may have properties that are hybrid between parabolic reflectors and driven arrays, providing a relatively compact circularly polarized antenna capable of having low wind load. Closed circuit or loop elements may provide increased gain over antennas using dipole turnstile reflector elements.

Abstract: According to one embodiment, an antenna apparatus comprises a leaky coaxial cable, a first housing, a second housing and a connecting unit. The first housing configured to retain a part of one end of the leaky coaxial cable. The second housing configured to retain a part of other end of the leaky coaxial cable. The connecting unit configured to connect the first housing with the second housing such that the direction of the second housing relative to the first housing can be alerted.