Abstract: An antenna system comprising a support structure and a multiband/multichannel wireless feeder configured for coupling antennas located proximate the top of a support structure with electronics located proximate the base of the support structure to overcome losses typically associated with coaxial cables. Such a multiband/multichannel wireless feeder includes a waveguide having a coupling at each end and a multiplexing waveguide network coupled at each end of the waveguide and configured to combine frequencies and applications.

Abstract: An injection seeded modular gas discharge laser system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 mJ or greater. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. The chambers can be controlled separately permitting separate optimization of wavelength parameters in the master oscillator and optimization of pulse energy parameters in the amplifying chamber. A preferred embodiment in a F2 laser system configured as a MOPA and specifically designed for use as a light source for integrated circuit lithography. In the preferred MOPA embodiment, each chamber comprises a single tangential fan providing sufficient gas flow to permit operation at pulse rates of 4000 Hz or greater by clearing debris from the discharge region in less time than the approximately 0.25 milliseconds between pulses.

Abstract: A horn antenna system having a strip line feeding structure of which size is reduced while cross polarized characteristics are kept. The horn antenna system, includes: a first horn antenna unit having a first horn antenna and a first ground made of metal, for radiating a signal; a second horn antenna unit having a second horn antenna and a second ground made of metal, for reflecting the signal to allow the second horn antenna unit to radiate the signal; and a feeding unit located between the first horn antenna unit and the second horn antenna unit, for feeding the energy to the first horn antenna unit and the second horn antenna unit, wherein the feeding unit is a stripe line.

Abstract: The present invention is directed, in part, to a carbon dioxide laser resonator gas comprising carbon dioxide, helium, and nitrogen and having a total halocarbon concentration less than about 100 parts per trillion. In one embodiment, the total halocarbon concentration is less than about 50 parts per trillion. The laser resonator gases, laser systems, and methods of the present invention provide high efficiency and high power laser light while reducing the cost of maintenance and improving the performance of a laser system by limiting the total concentration of halocarbon.

Abstract: A method for compensating for wavelength drift in a fiber-optic laser transmitter includes 1) controlling a temperature within the optoelectronic assembly at a defined level; 2) driving the optoelectronic assembly to emit light, wherein the emitted light has a wavelength that is within a channel of operation, the channel of operation including a range of wavelengths centered around a channel center wavelength; 3) accessing from memory within the optoelectronic assembly a control value associated with the temperature of the optoelectronic assembly at defined points within an operational lifetime of the optoelectronic assembly; and 4) recalculating the defined level by reference to the control value, whereby a wavelength of the optoelectronic assembly is maintained within the channel of operation despite an expected drift of wavelength.

Abstract: A multi-band antenna system for a portable communications device (e.g. a PC Card wireless modem) is disclosed. The multi-band antenna system comprises a dipole antenna, a reactive circuit, and transmission means coupled between the reactive circuit and the dipole antenna. For signals having frequencies within a first frequency band (e.g. the CDMA 0.86 GHz band), the reactive circuit operates as a trap, i.e. as a substantially high impedance, which enables a radiation impedance of a monopole formed by the presence of the trap to be coupled directly into the feed system (e.g. a diplexer) of the antenna system. The dipole antenna is configured and dimensioned to receive signals within a second frequency band (e.g. the PCS 1.92 GHz band). Second frequency band signals received by the dipole antenna are conducted through the signal conductor of the transmission means to the feed system substantially unimpeded by the reactive circuit.

Abstract: In a circuit arrangement for operating light sources, inexpensive technologies for power factor correction can be used in combination. Owing to the combination of a dual charge pump and a valley fill circuit it is also possible to adhere to relevant standards for rated current harmonics even at rated powers of over 25 W whilst maintaining low component loading.

Abstract: A patch antenna includes a metallic ground plate, a metallic radiating element, and a polymer plastic dielectric layer sandwiched between the radiating element and the ground plate. Top and bottom surfaces of the dielectric layer are primed with polymeric surfactants to provide better adhesive characteristics at low temperatures. The radiating element is fixed to the dielectric layer by compressing an adhesive layer applied to the radiating element between the radiating element and the priming layer applied to the top surface of the dielectric layer. The ground plate is fixed to the dielectric layer by compressing another adhesive layer applied to the ground plate between the ground plate and the priming layer applied to the bottom surface of the dielectric layer. A low noise amplifier may be integrated with the antenna by sharing the common ground plate and connecting the amplifier's signal trace to the radiating element via a conductor pin.

Abstract: The invention relates to a RFID chip that is contained inside a rubber tire to provide wireless communication of information concerning the tire. For instance, it may be desirable to communicate pressure and temperature information concerning a tire during its manufacture and/or usage. The RFID chip is attached to the inside of the rubber tire and is capacitvely coupled to a conductive belt contained inside the tire to provide an antenna for radio-frequency communications and reception.

Abstract: A low-profile dual-band antenna includes a ground plane. An “E”-shaped metal plate is located a first distance from the ground plane and includes first and second outer extensions and an inner extension of the metal plate. A feed tab connects the inner extension and the ground plane. A shorting tab connects the inner extension and the ground plane. The low-profile dual-band antenna communicates first radio frequency (RF) signals in a first RF band and second RF signals in a second RF band. The first RF signals and the second RF signals are vertical polarized signals. The low-profile dual-band antenna produces a radiation pattern that is omnidirectional in the azimuth plane and vertically polarized in a horizontal plane when communicating the first RF signals and the second RF signals. The first RF band and the second RF band can be independently tuned.

Abstract: A method and circuit for generating independent top and bottom corner correction using a single fourth order function is described. The top and bottom corner correction signal may be included in an east-west corrected voltage to correct an asymmetry of a picture with respect to a horizontal axis and a vertical axis of the picture. Two switch signals based on a ramping voltage, which is used to sweep an electron beam, and two clock signals control a sample-and-hold circuit. The sample-and-hold circuit is arranged to sample a fourth order voltage during a top portion and a bottom portion of the ramping voltage and provide two independent correction voltages Vout—top and Vout—bottom. The correction voltages are then provided for top and bottom corner correction to the east-west corrected voltage.

Abstract: Optical energy is provided to an optical amplifier by a first and a second pump laser. The optical energy that is provided is used as a basis for generating a gain associated with the optical amplifier. An error associated with the first pump laser may be identified. One or more parameters associated with the second pump laser may be controlled in response to the error such that the second pump laser increases an optical power output provided to the optical amplifier to compensate for the full or partial failure of the first pump laser. The adjustment in optical power output is used by the optical amplifier to substantially maintain the gain associated with the optical amplifier.

Abstract: The present invention provides a control system for a modular high repetition rate two discharge chamber ultraviolet gas discharge laser. In preferred embodiments, the laser is a production line machine with a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. Novel control features specially adapted for a two-chamber gas discharge laser system include: (1) pulse energy controls, with nanosecond timing precision (2) precision pulse to pulse wavelength controls with high speed and extreme speed wavelength tuning (3) fast response gas temperature control and (4) F2 injection controls with novel learning algorithm.

Abstract: A method for calibrating a multi-channel laser emitter in an optoelectronic transceiver or an optoelectronic transmitter for a first wavelength includes monitoring the wavelength of optical signals from the laser emitter while varying its temperature as well as other operating conditions, and then storing calibration information in the memory of a microprocessor. The initial values of the calibrating procedure are reset and the calibrating procedure is repeated to obtain calibration information for a next desired wavelength.

Abstract: A phase modulator comprised of a plurality of circuit paths operates to receive a data signal and a radio frequency carrier signal and to couple the radio frequency carrier signal into an antenna at a feedpoint associated with a circuit path, whereby the electric field vector phase of the emitted radio frequency signal is determined by the data state of the received data signal. The circuit has at least one circuit path, which is determined by the data state of the input data signal, to couple the radio frequency carrier signal to the antenna feedpoint to adjust the phase.

Abstract: A method for calibrating a multi-channel laser emitter in an optoelectronic transceiver or an optoelectronic transmitter for a first wavelength includes monitoring the wavelength of optical signals from the laser emitter while varying its temperature as well as other operating conditions, and then storing calibration information in the memory of a microprocessor. The initial values of the calibrating procedure are reset and the calibrating procedure is repeated to obtain calibration information for a next desired wavelength.

Abstract: Driver circuits of the present invention provide current to drive laser diodes. The output current of the driver circuit includes a data signal and a low frequency tone signal. The low frequency tone signal is within the bandwidth of a power control feedback loop. The tone signal introduces low frequency noise into the output signal of the driver circuit. The low frequency noise causes jitter at the zero crossing points of the driver circuit output signal. A laser driver circuit of the present invention provides a compensation current to a laser diode. The compensation current is out of phase with the tone signal. The compensation current eliminates the low frequency noise in the output signal of the laser driver circuit.

Abstract: The invention relates to a background lighting system for a liquid crystal display, more particularly to an electronic circuit for operation of one or more discharge lamps. A DC/AC full-bridge inverter circuit generates two voltages whose AC components are phase-shifted by 180°. The discharge lamps are supplied with the sum of these two AC voltages.

Abstract: An n-InP cladding layer, a GRIN-SCH-MQW active layer, a p-InP cladding layer, p-InGaAsP contact layer and a p-side electrode are laminated sequentially on an n-InP substrate. Moreover, a film having high reflectivity is laminated on a reflection side end surface, and a transmission film is laminated on an emission side end surface. The transmission film has a first film and a second film. The second film is composed of an equivalent film composed of three layers.

Abstract: The present invention provides a multimode semiconductor laser module. The module comprises a multimode laser element 34, an optical filter 54, a light-receiving element 52 and a temperature regulator 24. Multimode light from the laser element 34 is transmitted through the filter 54 and then detected by the light-receiving element 52. The output of the light-receiving element 52 changes according to the degree of overlap between the oscillation wavelength spectrum of the laser element 34 and the transmission wavelength region of the filter 54. The temperature regulator 24 modifies the oscillation wavelength region toward the desired region in response to the output of the light-receiving element 52. As a result, the oscillation wavelength region is stabilized.