Lucent Technologies Inc.

At+t Corp.

At&t Bell Laboratories

At&t Ipm Corp.

Robert W Wilson

Bernard Glance

James G Evans

Martin V Schneider

Giovanni Vannucci

Theodore Sizer

Gregory Alan Wright

Thomas C Cannon, Jr

In an antenna having a conductor of a length L and a dielectric material with a dielectric constant .epsilon..sub.r1 contacting the conductor, a matching dielectric layer .epsilon..sub.r2 less than .epsilon..sub.r1 matches the dielectric constant to free space. Preferably .epsilon..sub.r2 =.sqroot..epsilon..sub.r1 , L=.lambda..sub.o /(2.sqroot..epsilon..sub.r1 ). The depth d of the second dielectric is a quarter wavelength in the matching layer. Multiple matching layers with successively decreasing dielectric constants forms embodiments. In one embodiment the resonant conductive arrangement is a microstrip patch antenna with the dielectric material supporting a patch and matching layer covering the dielectric material.

Small antennas such as microstrip patch antennas

A microstrip patch filter in which a dielectric has a ground plane printed on one of its faces and a conductive arrangement printed on the other of said faces, the conductive arrangement includes a flat patch, input and output leads electromagnetically coupled to the flat patch, the flat patch or the dielectric substrate has a reactance-enhancing metallic constriction located along a portion of the patch. When the constriction is in the patch it forms a current-concentrating inductive constriction. When the constriction is in the dielectric substrate, it enhances the capacitance. In an embodiment, the patch has two mutually-transverse constrictions that divide the patch into four sub-patches cross-connected by current-concentrating inductive constriction.

Microstrip patch filters

Methods and systems for locating objects are disclosed. An electronic tag is attached to an object before storing the object. The electronic tag is identifiable by a unique response code. The response code and information pertaining to the object are recorded and the object may then be stored. To locate the object, the response code is entered into an interrogator. The interrogator sends a signal that causes the tag to emit a sound. The system thus allows for random storage of objects and is also useful for locating misplaced objects.

Object locator system and methods therefor

In a resonator in which a ground plane and a patch sandwich a dielectric, a slot in the patch concentrates emanation of radiation from the slot. Shorting conductors form the ends of the resonator. A dielectric cover over the slot matches the dielectric constant of the substrate to that of free space. Quarter-wave chokes at the ends of the resonator suppress currents in the ground plane.

Microstrip patch antennas with radiation control

The effectiveness of a microstrip conductor antenna, such as a patch antenna, is improved at any particular frequency by making the thickness of the conductor sufficiently small to reduce shielding and losses caused by the skin effect and make currents at the upper and lower surfaces couple with each other and make the conductor partially transparent to radiation. In one embodiment the thickness is between 0.5.delta. and 4.delta.. Preferably the thickness is between 1.delta. and 2.delta. where .delta. is equal to the distance at which current is reduced by 1/e., for example 1.5 to 3 micrometers at 2.5 gigahertz in copper. According to an embodiment, alternate layers of dielectrics and radiation transparent patches on a substrate enhance antenna operation.

High efficiency microstrip antennas

Dielectric components extend between top and bottom surfaces of a ground plane in a resonant microstrip patch antenna over a distance of one-quarter-wavelength of a resonant frequency of the antenna. The components form quarter-wave chokes within which waves cancel with reflected waves and reduce currents in the bottom surfaces of the ground plane. This reduces back lobe responses.

Antennas with means for blocking current in ground planes

A monolithically integrated wideband optical filter which is rapidly tunable to a large number of optical frequencies over a wide optical frequency range comprises two series connected optical filters of different resolutions formed in a semiconductive wafer. A control circuit applies electrical energy to predetermined controllably transmissive waveguides connecting components of the filters defined in the wafer. This tunes the overall filter to a desired one of a plurality of optical frequencies. Application of such electrical energy creates frequency selective pathways through the wafer able to pass one of up to hundreds of selected optical frequencies over the entire bandwidth of a semiconductive medium. This filter is economical to construct and is useful in high capacity, high speed optical communications networks.

Rapidly tunable wideband integrated optical filter

An optical passband filter having a frequency transition that is several of orders of magnitude narrower than prior optical filters includes two frequency routing devices. The first frequency routing device has one input for receiving the input signal and at least N outputs, where N corresponds to the number of frequencies that compose the input signal. The N outputs of the first frequency routing device are each coupled to inputs of a second frequency routing device. The outputs of the second frequency device each correspond to one of the selected output frequency bands into which the input signal is to be divided. A multiplexed input signal containing several different frequency channels is divided into bands that are each directed to respective outputs of the second frequency routing device. The frequency transition between the various bands may be as small as the frequency resolution between adjacent outputs of the first frequency routing device.

Optical passband filter

A monolithically integrated wideband laser which is rapidly tunable over a wide optical frequency range comprises two series connected frequency routers of different resolutions formed in a semiconductive wafer defining a tuned cavity. A control circuit applies electrical energy to predetermined controllably transmissive waveguides connecting the frequency routing devices with reflective elements defined in the wafer. This tunes the laser to a desired one of a plurality of optical frequencies. Application of such electrical energy creates frequency selective pathways through the wafer able to support up to hundreds of selected lasing frequencies across the entire bandwidth of a semiconductive medium. This laser is economical to construct and is useful in high capacity, high speed optical communications networks.

Rapidly tunable wideband integrated laser

A variable optical delay line which can delay an optical signal by a selected interval of time comprises an input wavelength router connected to an output wavelength router by means of optical waveguides of different lengths. A wavelength shifter coupled to the input of the input wavelength router shifts the wavelength of the received signal to a desired wavelength. Depending on the wavelength of the signal from the wavelength shifter, the received signal is directed to a specific one of the waveguides of different lengths to provide a delay which is controllable. The output wavelength router directs the optical signals from the various waveguides of different lengths to a common output waveguide.

Optical delay line

A monolithically integrated optical filter which is rapidly tunable over a wide optical frequency range comprises an input frequency router connected to an output frequency router by means of controllably transmissive waveguides. A control circuit applies electrical energy to predetermined controllably transmissive waveguides to tune the optical filter to a desired one or more of a plurality of multiplexed input optical frequencies. This filter is economical to construct and is useful in high capacity, high speed optical communications networks.

Growing community of inventors

Holmdel, NJ, United States of America

Robert W Wilson