Showing papers on "Stub (electronics) published in 1998"

Method of making a high density integral test probe

Abstract: A high density integrated test probe and method of fabrication is described. A group of wires are ball bonded to contact locations on the surface of a fan out substrate. The wires are sheared off leaving a stub, the end of which is flattened by an anvil. Before flattening a sheet of material having a group of holes is arranged for alignment with the group of stubs is disposed over the stubs. The sheet of material supports the enlarged tip. The substrate with stubs form a probe which is moved into engagement with contact locations on a work piece such as a drip or packaging substrate.

Circularly polarised microstrip antenna with a tuning stub

Abstract: A simple circular polarisation (CP) design of microstrip antennas using a tuning stub is proposed and studied. It is also demonstrated that, by applying this CP design method to a circular microstrip patch with a cross slot having equal slot lengths, a compact circularly-polarised microstrip antenna can easily be implemented, with much more relaxed manufacturing tolerances as compared to the case of using a cross slot of unequal slot lengths. Details of the antenna designs are described, and experimental results are presented and discussed.

A versatile leaky-wave antenna based on stub-loaded rectangular waveguide .I. Theory

Abstract: A new leaky-wave antenna is presented that possesses many desirable features and is suitable for application to both the millimeter-wave and microwave ranges. These desirable features, some of which are unusual, include a simple configuration, a wide flexibility in the range of available beamwidths, the ability to control the beamwidth and the direction of the beam essentially independently, and negligible cross polarization at all scan angles. The antenna structure consists of a parallel-plate stub guide of small height, less than a half wavelength, located off center on the top of rectangular waveguide. The beamwidth is easily controlled from very wide to very narrow by adjusting the stub width or location. The article presents the principle of operation and the theory, employing a new transverse equivalent network that is accurate, but also simple, so that it permits rapid and inexpensive numerical calculations.

High-speed backplane

Abstract: A backplane consisting of segmented bus lines on a mother board with loop-through connections to active transceivers mounted on connectors to daughter boards. The transceivers isolate the interconnect to the daughter boards from the bus lines. The loop-through transmission line on the connectors preserves the impedance of the bus lines and allows the interconnect stub to the transceivers to be short, minimizing reflections and enabling high-speed backplane operation. The connectors are removable from the motherboard for repair.

Printed antenna structure for wireless data communications

Abstract: A printed antenna structure for transmission of radio frequency energy in the gigahertz range that provides good dispersion characteristics and a relatively wide bandwidth using a thin substrate material. The antenna includes a thin printed circuit board having top and bottom surfaces. The bottom surface features an electrically conductive ground plane layer. The top surface features a microstrip feed line structure which is connected to a radiating element. The microstrip feedline extends over the ground plane but the radiating element does not. The radiating element has a main V-shaped segment for coupling radio energy over a wide spatial region, and a tuning stub is sequentially connected to the V-shaped segment. Overall, the printed antenna has an overall shape which resembles a hook in oder to minimize the space occupied on the printed circuit board.

Folded spiral antenna for a portable radio transceiver and method of forming same

Abstract: A spiral antenna (100) having a feed-point end and a termination end for use within a portable two-way radio housing includes a ground substrate (102) and a number of spiral elements (103, 105) having a number of segments that form two or more spiral shapes. A shorting stub (107) connects the planar elements at a termination end for effectively increasing the feed-point impedance of the spiral antenna (100). The spiral elements (103, 105) may be positioned in a planar arrangement (FIGS. 1 and 2) or may be stacked in separate planes (FIGS. 3 and 4) for forming a limited space antenna having a substantially 50 ohm feed-point end impedance at resonance.

Method for the manufacture or repair of a blisk by linear friction welding

Abstract: A method of making a BLISK by linear friction welding, comprises providing a stub on the circumferential surface of a turbine disk and defining a weld joint surface on the radially outermost face of the stub. The weld joint surface follows the annulus curvature in axial and circumferential directions while remaining flat in a third direction. A blade is applied radially to the stub and linear friction welding of the blade to the stub is effected by oscillating the blade in said third direction while applying a welding force inwardly along the blade.

Microwave antenna having wide angle scanning capability

Abstract: A planar array antenna having a switching matrix that couples an RF signal to two distributed ferrite scanning line feeds that feed a planar continuous transverse stub array antenna. The scanning line feeds couple RF energy to the antenna from opposite sides to form a total of four beams offset in space that each cover different angular scan sectors. The antenna has reduced complexity and lower design and production costs. The use of dual ferrite scanning line feeds, the switching matrix, and the continuous transverse stub antenna to obtain wide-angle scanning provides significantly improved performance. The present invention uses the two distributed ferrite scanning line feeds to obtain greater scan coverage at upper millimeter-wave frequencies, where realizable ferrite materials are less active and provide diminished scan capability. The scanning line feeds and planar array antenna may be designed so that the four scan sectors are contiguous, to increase the angular scan coverage of the antenna. The switching matrix is used to sequentially feed each of four RF ports, which effectively produces a single beam that scans over the four contiguous scan sectors.

Reconfigurable millimeterwave filter using stubs and stub extensions selectively coupled using voltage actuated micro-electro-mechanical switches

Abstract: A reconfigurable filter system designed using micro-elecro-mechanical (MEM) switches is disclosed. The filter comprises a transmission line with one or more filter stubs coupled to the transmission line by MEM switches. The impedance of the filter system is altered by selectively opening and closing the MEM switches, which alters the filter characteristics of the filter system. Alternatively, the characteristics of the filter system are altered by using the MEM switches to selectively alter the length of filter stubs attached to the transmission line.

Electronic transport in quantum waveguide systems with attached stubs

Abstract: Single-mode quantum transmission properties of a quantum waveguide system with attached stubs are studied in the ballistic regime. The formation of energy bands is achieved in the case of periodic structure mainly around the energies where a single stub possesses antiresonances. A single defect in the otherwise periodic structure introduces a resonant (or an antiresonant) state. We find that this state is not an exponentially localized state, and is not a Fano-type resonance (although it originates from it), but more a well-known Lorentzian-shaped Breit-Wigner transmission resonance. When this state falls in the energy band, then it forms an antiresonance. A strong magnetic field creates additional quasibound states.

A versatile leaky-wave antenna based on stub-loaded rectangular waveguide .II. Effects of flanges and finite stub length

Abstract: For pt.I see ibid., vol.46, no.7, p.1032-41 (1998). A new leaky-wave antenna was presented and discussed in Part I that possesses many desirable performance features. The antenna structure is also simple in form, consisting of a rectangular waveguide with an offcenter stub on its top wall. Part I presented the principle of operation and the basic theory in which the stub guide was idealized to be infinitely long (or high) in order to stress the essential features. In practice, however, the stub guide has a finite length (or height) and it may be terminated by a flange or a ground plane or simply remain in the form of a pair of baffles. The modifications in the theory and the associated performance considerations under these practical circumstances are treated in this paper.

Simultaneous realization of millimeter wave uniplanar shunt stubs and dc block

Abstract: The exploitation of the potentialities linked to uniplanar technology for telecommunications is only at its beginning and even if significant advances have been realized, the context remains evolutive This paper therefore proposes a new concept for the generation of millimeter wave uniplanar shunt stubs by means of slotline resonator instead of coplanar line resonators Thus, the short end slotline stub has now the ability to be configured as shunt and series stubs, and therefore acts as a bandpass and bandstop filter respectively This gives additional degrees of freedom to the design Compared to the existing CPW short-end shunt stub, the advantages which may be derived from the use of the proposed framework are: additional degrees of freedom, lower radiation loss, larger bandwidth, high compactness and a reduction of the number of air bridges which are potentially expensive to build Its worth noting that the new short end shunt stubs provides both bandpass behavior and dc blocking simultaneously which is not the case for the standard CPW shunt stub Furthermore, the present paper proves that the capability to generate shunt stubs in slot line form allows one also to relax the limitations inherent to the realization of low and high impedance levels In this way, various shunt stubs in slotline form with proposed geometries including rectangular and slot ring shapes are fabricated and accurate on-wafer measurements are performed over a large band of interest (1-50 GHz), The realization of these shunt stubs is detailed and also confirmed with experimental results

Dual-band stub antenna

Abstract: A broadband antenna, including a centrally-positioned radiating element, a dielectric support element generally surrounding the centrally-positioned element, and a linear radiating element, which extends along at least part of the length of the centrally-positioned element and a portion of which is wound over the support element around the centrally-positioned element. The centrally-positioned element preferably includes a linear metallic radiator, and the linear radiating element preferably includes a wire, such that the portion of the wire that is wound over the support element defines a helical radiator.

Engaging component for cabinet structures

Abstract: An engaging component includes an engaging stub in the shape of a hollow cylinder with the bottom being secured on a first object to be engaged, and an outer sleeve in the shape of a hollow cylinder having a shank arranged to be inserted into the central hole of the engaging stub through a second object to be engaged. A positioning rod is insertable into a central hole of the outer sleeve, the positioning rod preventing the shank from being taken out of the central hole of the engaging stub, thereby locking the outer sleeve to the engaging stub.

Computer docking station with anti-slip mount

Abstract: A computer docking station for a portable computer has an enclosure to mate physically and electrically with the portable computer. The docking station has an anti-slip mechanism to hold the enclosure to a surface. The anti-slip mechanism has at least one suction cup with a stub portion hidden within the enclosure and a cup portion that extends out through an aperture in the enclosure. A shaft with an eccentric cam section is connected to the stub portion to cause the stub portion to move in opposing first and second directions when the shaft is rotated. A knob is connected to the shaft and exposed externally of the enclosure so that a user can turn the knob to rotate the shaft. When the user moves the knob to a lock position, the mechanism moves the stub portion in the first direction, drawing the stub portion inward relative to the enclosure aperture, thereby causing the cup portion to cup and form a cavity between itself and the surface. This action creates a suction force relative to the surface to hold the enclosure to the surface and to resist sliding of the enclosure over the surface during docking or undocking. To release the enclosure, the user moves the knob to an unlock position. The mechanism moves the stub portion in the second direction, pushing the stub portion toward the enclosure aperture, thereby causing the cup portion to flatten and release the suction force.

Analysis of continuous transverse stub (CTS) array by Floquet mode method

Abstract: A continuous transverse stub (CTS) array antenna is a low-cost, low-profile, easy-to-fabricate, innovative two-dimensional aperture antenna invented by W. Milroy (1993) of the Hughes Aircraft Company. A CTS array is eventually an array of long slots (stubs) which are fed by a parallel plate waveguide. An analysis using one-dimensional periodic Floquet mode expansion and method of moments to solve the active reflection coefficient of the continuous transverse stub (CTS) array radiated to free space has been formulated and solved. A computer program based on this solution has been developed and validated by comparing the results with HFSS/Eminence model. This Floquet mode solution of the CTS array can take care of the two-dimensional scan coverage in arbitrary continuous scan angles, which is not possible for HFSS/Eminence model. The solution also incorporates the multiple-layer superstrate matching radome effect. By using this Floquet mode solution for active reflection coefficient of the CTS stub radiated to space and the solution of the E-plane waveguide tee junction, a scattering matrix formulation can be obtained for each stub section of the CTS array. Thus, the far-field patterns, beam pointing angles, the antenna gain (or loss), and the input VSWR of the entire CTS array can be predicted. Computer programs based on the above scattering matrix cascading formulations for the end-fed or center-fed series-feed CTS antenna arrays have been developed.

Analysis of 3-D cylindrical structures using the finite difference time domain method

Abstract: Recently, there has been a growing interest in using cylindrical transmission line structures in microwave applications. In this paper, the Finite Difference Time Domain (FDTD) method is used to characterize and dimensional cylindrical coplanar waveguide (CCPW) geometries. Specifically, a CCPW series stub and a three-section CCPW filter are studied theoretically and experimentally. Absorbing boundary conditions are employed to truncate the mesh at the end walls and the outer radial boundary.

ABS sensor for a heavy goods vehicle non-drive axle with a disk brake

Abstract: Non-drive axle has a bearing hub unit (10) on an axle stub (11), a disk brake (6), an ABS sensor element (21) and an impulse ring (22) turning concentrically round the bearing hub unit. The sensor element scans an envelope of cone measuring surface on the impulse ring that converges towards the open hub end. The sensor element's axis is placed diagonally at 32 - 38 degrees angle to the axis of the axle stub.

Bus system and circuit board

Abstract: A bus system with an improved propagation velocity, comprising main lines, and a plurality of stub lines provided on a one-to-one correspondence with a plurality of modules, and connecting the corresponding modules to the main lines.

Shock absorber strut with axle stub for motor vehicle

Abstract: The shock absorber strut has a positioning connection (15,27) between the tubular body (3) of the strut and the axle stub. The positioning connection enables a precise alignment in the circumferential direction of the components forming the clamp connection. The positioning connection consists of a radially protruding pin (27) and slot (15) formed on the respective outer faces of the corresponding component parts. The tubular body has a stop (29) which effects positioning of the axle stub along the longitudinal axis of the strut.

Improvements in or relating to the friction welding of components

Abstract: A method of making a BLISK by linear friction welding, comprises providing a stub on the circumferential surface 49 of a turbine disk 50 and defining a weld joint surface 55 on the radially outermost face of the stub 52. The weld joint surface 55 follows the annulus curvature in axial and circumferential directions while remaining flat in a third direction 48,60. A blade 53 is applied radially to the stub 52 and linear friction welding of the blade 53 to the stub 52 is effected by oscillating the blade 53 in said third direction 48,60 whilst applying a welding force inwardly along the blade 53.

Body jewelry device and method of making the same

Abstract: The body jewelry device has a post part and cap part with the cap part having an integral and threaded stub. The post part has an integrally formed and complementary threaded bore for receiving the threaded stud. The cap part post is thereby securely, but releasably, coupled to the post part. In a preferred embodiment, the cap has a counter sink for receiving an end of the post. The cap for the body jewelry may be formed by shaping a stock material into a generally enlarged ornamental piece. A stub is integrally formed on the generally enlarged shape and threads formed on the stub. A counter sink may be formed around the stub for receiving an end of the post. The stub threads are constructed to threadably mate with an opposing and complementary bore on a post.

Slot coupling type dielectric resonator antenna

Abstract: PROBLEM TO BE SOLVED: To provide the slot coupling type dielectric resonator antenna which has circular polarization characteristic of superior antenna efficiency, gain, and axis ratio over a wide band and is simple in radiation element shape and easily manufactured. SOLUTION: A radiation element 1 composed of a dielectric resonator, a ground conductor plate 3 having a cross slot 2 in asymmetrical structure in the center, a dielectric plate 4, an electric feeding circuit board 7 provided with a feed line 5 and a matching stub 6 are stacked in order, and the cross slot 2 excites the radiation element 1 by electromagnetically coupling the feeder line 5 with the radiation element 1. Furthermore, two slot parts of the cross slot are formed into an asymmetrical structure so as to enable circular polarization without deforming the element shape of the radiation element.

RF/microwave oscillator having frequency-adjustable DC bias circuit

Abstract: A frequency-adjustable direct current biasing circuit is disclosed for providing a DC bias voltage or a DC connection to ground for an RF or microwave circuit without substantially affecting the RF or microwave signal of the circuit. The biasing circuit includes a transmission line having a first portion for connection to the RF circuit and a second portion connected to a low-impedance-to-ground structure, such as a bypass capacitor or a DC path to ground. The electrical length between the first and second portions is about 90 degrees. The biasing circuit further includes an open ended tuning stub coupled to the transmission line that has a length that is adjustable. By adjusting the length of the tuning stub, the biasing or grounding circuit can provide better isolation for RF energies at different selected frequencies. Also disclosed herein is a dielectric resonator oscillator (DRO) that uses the frequency-adjustable biasing circuit. Further disclosed is a DRO that includes a FET gate return having an RF-shunted, relatively high resistance coupled to the gate of a field effect transistor by way of a quarterwave transmission line. This improved FET gate return provides for reduced phase noise of the DRO.

Propeller shaft for automobile

Abstract: PROBLEM TO BE SOLVED: To smoothly absorb axis-directional displacement exerted on a propeller shaft at the Lime of automobile front collision in an automobile propeller shaft provided with a sliding type constant velocity universal joint. SOLUTION: A hollow part 12 for advancing a stub shaft 2 spline-connected an inner ring 5 of a sliding type constant velocity universal joint 3 is provided in a tubular shaft 1 connected to an outer ring of the universal joint 3, a sealing plate 8 integrated with a core bar 81 and rubber 82 is fitted to an opening end part of the outer ring 4, a through hole 84 for passing the stub shaft 2 through is provided in the central part of the core bar 81, and axis-directional positioning for the inner ring 5 relating to the stub shaft 2 is conducted by a fixing device 23 releasable when an excessive axis-directional load is applied. The sealing plate 8 is surely held at the time of ordinary traveling by the constitution mentioned above. The stub shaft 2 passes through the through hole 84 of the core bar 81 of the sealing plate 8 and break the rubber 82 to rush smoothly into the hollow part 12 at the time of automobile collision. COPYRIGHT: (C)1999,JPO

Stub loaded helix antenna

Abstract: A helical antenna having stubs spaced along the helix curve length and extending toward the central axis of the helix, such that the performance characteristics of the antenna, such as gain and circular polarization, are maintained while the size of the antenna, diameter and length, are reduced.

Toothbar and toothbar center support arrangement for baler pickup reel

Abstract: A baler pick-up reel includes a reel shaft to which is fixed a center toothbar support. A first set of toothbars are located to one side of the center toothbar support and respectively have stub shafts at first ends which are respectively received in a first set of equi-angularly spaced bosses forming part of the toothbar support and projecting in a direction opposite to the first set of toothbars. Similarly, a second set of toothbars are located on an opposite side of the center toothbar support and respectively include stub shafts at first ends that are respectively received in a second set of equi-angularly spaced bosses forming part of the toothbar support and projecting in a direction opposite to the second set of toothbars. A plurality of teeth are mounted to each toothbar and have tines which are evenly spaced across the working width of the reel.