摘要:
An acoustically coupled antenna which can be configured as a transmitting or receiving antenna for coupling between an electrical circuit (transmitter or receiver) and an electromagnetic propagating medium such as the atmosphere. The antenna is a two port device in which one port is connected to the electrical circuit and the second port includes a transducer which interfaces (radiates or receives) electromagnetic energy with the propagating medium. The ports are acoustically coupled to each other by forming the device as a stacked crystal filter with three conductive electrodes separated by two piezoelectric resonating elements. The first port comprises two of the electrodes separated by one of the piezoelectric elements, and the second port shares the electrode separating the two piezoelectric elements, and further includes the second piezoelectric element and the final electrode. The electrical signals in the bandwidth of the antenna at the two ports are acoustically coupled by the coupled resonators of the stacked crystal filter for translating energy from one port to the other while providing electromagnetic isolation by virtue of the acoustic coupling.
摘要:
A pre-pulsed magnetic field generation circuit for a fiber-based, magneto-optic (MO) optical modulator or switch for use in an interferometer is provided. The pre-pulsed magnetic field is used to control the amount of rotation in the state of polarization (SOP), and therefore, the ON-OFF extinction ratio. The circuit includes a pair of amplifier circuits that control the current through a coil to generate the pre-pulsed magnetic field. One amplifier controls a magnitude of a steady state portion of the magnetic field, while the other controls both the amplitude and duration of a pre-pulse portion of the magnetic field.
摘要:
A passive RFID tag suitable for attachment to an electrically conductive surface is provided. The passive RFID tag includes a dielectric substrate, an RFID chip for storing data, and an RFID antenna structure operatively connected to the RFID chip wherein the RFID antenna structure comprises a slotted inverted L-shape. A method of manufacturing a passive RFID tag includes forming an antenna structure on a conductive layer, the antenna structure comprising a slotted inverted L-shape. The method further includes operatively connecting an RFID chip with the antenna structure. A method associated with a passive RFID tag includes providing a passive RFID tag. The passive RFID tag includes a dielectric substrate, an RFID chip for storing data, and an RFID antenna structure operatively connected to the RFID chip wherein the RFID antenna structure comprises a slotted inverted L-shape. The method further includes operatively connecting the passive RFID tag to a conductive surface.
摘要:
An integrated fiber optic switch based on the magneto-optic effect of magnetic materials suitable for optical fiber networks is presented. The switch is based on the Faraday Effect exhibited by magneto-optic materials. The all-fiber magneto-optic switch has a beam splitter at the input that splits an incoming signal into orthogonal polarized paths. Each path has at least one magneto-optic Faraday rotator (MOFR) controlled by a field. When the field is present, the polarization of the optical beam changes, thereby turning the switch on or off. A beam coupler couples the orthogonal polarized paths at the output of the all-fiber magneto-optic switch. The switch is constructed in the Mach-Zehnder configuration, utilizing two 3 dB couplers, isolators and MOFRs fabricated on silicon-on-insulator.
摘要:
An electronic individual descriptive record system for storing the individual's identification and descriptive data on a programmable electronic identification and data storage module carried with the individual so that the individual's identification, the individual's descriptive data and the individual itself become one. The system includes an implantable programmable electronic identification and data storage module carried by the individual, and a reading and recording device which communicates with the electronic identification and data storage module.
摘要:
An optical modulator device comprised of a semiconductor laser acoustically coupled to a thin film resonator is disclosed herein. The thin film resonator includes a piezoelectric crystal layer having first and second opposing surfaces, with the first opposing surface being in contact with a metallic electrode. The semiconductor laser is interposed between an acoustically reflective surface and the second surface of the thin film resonator. In a preferred implementation the acoustically reflective surface is defined by a submount underlying a substrate upon which is mounted the semiconductor laser.A frequency modulator exhibiting an improved modulation index may be achieved by integrating a superlattice structure within the active region of the semiconductor laser. The superlattice structure will preferably include a cascaded stack of stacked pairs, each stack pair constituent being of a thickness equivalent to a multiple of one-half of the wavelength of optical emission produced by the semiconductor laser of the superlattice.The optical device may also be implemented in the form of a phase modulator disposed to provide a phase-modulated optical output of predetermined frequency. Phase modulation is produced in the absence of appreciable frequency modulation by configuring the thin film resonator to be of a longitudinal length less than that of the semiconductor laser.
摘要:
An electronic livestock record system stores the individual animal's identification and performance data on a programmable electronic identification and data storage module carried with the animal so that the animal's identification, the animal's performance data and the animal itself become one. The system includes a programmable electronic identification and data storage module carried by the animal, and a reading and recording device which communicates with the electronic identification and data storage module.
摘要:
A high power semiconductor device with integral heat sink capable of accommodating substantial heat flux on the order of one kw per cm.sup.2. The integral heat sink is formed on the active surface of the semiconductor and utilizes an AlN thin film of high purity to provide a low thermal impedance heat conductor for removing heat directly from the active semiconductor surface. A microchannel heat sink is formed on the A1N thin film and has a source of cooling fluid flowing through the microchannel heat sink for conducting heat away from the sink. The result is the ability to conduct large heat fluxes away from the intimately contacted heat generating semiconductor surface to the cooling fluid in the microchannel heat sink and thus operate the semiconductor under substantially higher power than has been practical heretofore in a device of such simplicity.
摘要:
A Compact Reduced Parasitic Resonant Frequency Pulsed Power Source at Microwave Frequencies is disclosed which uses a series of stacked IMPATT diodes with thick metallic heat sinks interposed between each of the IMPATT diodes with the effective heat sink of each heat sink being roughly equivalent to the diode radius in length. The effective heat sink length is matched through the disclosed analysis to the effective heat sink of the base heat sink which is located at the bottom of the stack of IMPATT diodes. The diodes are operated in a pulsed fashion and the effective heat sink length is matched to the effective heat sink of the base heat sink that the temperature of the stacked IMPATT diodes track together in time.
摘要:
This invention is directed in general to polymers (including oligomers) that contain carboxyl-terminated lactone acrylates, to a process for their preparation, and to coating, ink, adhesive, and sealant compositions (including the cured coatings, inks, adhesives, and sealants) that are obtained by crosslinking the above compositions by various means. The cured compositions, which are, for example, high-quality industrial finishes, are made by incorporation of various conventional crosslinking agents and other normally-used formulating ingredients with the polymeric compositions of the invention.