Gte Laboratories Incorporated

Robert J Regan

Paul O Haugsjaa

William H McNeill

Joseph Martin Lech

Scott J Butler

Joseph M Proud

Anthony B Varallo

Zvi Ben-Aharon

Adrian I Cogan

Carl F Buhrer

Wojciech W Byszewski

Alfred E Feuersanger

Peter E Norris

William C Rideout

Donald H Baird

Douglas D Tang

William F Nelson

A reconfigurable ring architecture for RF transport over fibers which eliminates the need for multiple pairs of fibers to serve multiple microcells and the need for backup communications lines as a result of system failure due to a fiber break. The ring architecture has a plurality of remote units which are interconnected to a host unit in a serial fashion. The host unit transmits signals to the plurality of remote units and receives signals from the plurality of remote units. Each of the remote units having photodetectors for receiving the transmitted signals and an antenna/transmitter for receiving other signals from another source; a splitter for splitting the transmitted signals into two parts, one part of the signals being output from the remote unit and the other part of the signals being transferred to adjacent remote units and then back to the host unit; and a transmitter for transferring the other signals from the remote unit to adjacent remote units and then back to the host unit. The transmission and reception of signals taking place even in the event of failure of a remote unit or the interconnection between remote units.

Reconfigurable ring system for the transport of RF signals over optical

A power amplifier circuit utilizes vertical power transistors, such as static induction transistors, field effect transistors, or bipolar junction transistors, in a configuration where an ungrounded terminal serves as a common node while a separate reference terminal is connected directly to ground. A transformer of appropriate bandwidth couples an rf input signal to the input terminals of the transistor such that the input terminals are floating relative to ground. The novel amplifier circuit establishes separate electrical paths between the common terminal and the input circuit and between the common terminal and the output circuit. Thus, negative feedback is not present in the common lead, thereby improving gain, power output, and efficiency. Moreover, the circuit, in either a BJT, FET, or SIT configuration, can be fabricated on thinned semiconductor chips to form a transistor package in which the chips are bonded directly to the package heatsink.

Amplifier package using vertical power transistors with ungrounded

Ignition of high intensity discharge (HID) lamps can be enhanced by the application of ultrahigh frequency (UHF) electric fields at modest power levels. The implementation of UHF power assisted starting offers considerable advantage over known prior art lower frequency power starting methods. Solid state circuits and coupled means can be utilized as described therein.

Method of and apparatus for ultrahigh frequency starting of high

Apparatus for supporting a group of optical fibers in proper alignment with associated laser devices and rear-facet photodetectors. The photodetectors and grooves for supporting the optical fibers are fabricated in a carrier member of device quality silicon. An array of a row of laser devices is moved laterally along a slot in the carrier member transverse to the grooves so as to align each laser device with a groove and with a photodetector. One or more carrier members may be mounted on a supporting structure adapted to receive them.

Mounting apparatus for optical fibers and lasers

A high-gain, high-frequency, high-power, push-pull amplifier employing a pair of static induction transistors (SIT's) in common-source configuration. A pair of capacitances each of approximately the same capacitive value as the drain-to-gate parasitic feedback capacitance of each SIT are cross-coupled between the drains and gates of the pair of SIT's to neutralize the drain-to-gate capacitances and provide stable operation.

High-frequency, high-gain, push-pull amplifier circuit

Energy source of a low power high frequency oscillator section driving a high power high gain amplifier section. The amplifier section includes one or more SIT's. The dc operating potential is applied to the drain electrode of one of the SIT's and is supplied to the other through a dc path from the source electrode of the one SIT to the drain electrode of the other. Operating potential from the dc biasing network between the source and gate electrode of an SIT in the amplifier section is conducted through a dc path to a transistor in the oscillator section to provide operating power for the oscillator section. The oscillator output is connected through a high frequency coupling dc blocking path to the amplifier input to provide a drive signal to be amplified and extracted at the amplifier output.

High frequency energy source

A power source consisting of a low power high frequency oscillator section driving a high power high gain amplifier section. The amplifier section includes one or more SIT's. The dc operating potential is applied to the drain electrode of one of the SIT's and is supplied to the other through a dc path from the source electrode of the one SIT to the drain electrode of the other. Operating potential from the dc biasing network between the gate and source electrodes of an SIT in the amplifier section is conducted through a dc path to a transistor in the oscillator section to provide operating power for the oscillator section. The oscillator output is connected through a high frequency coupling dc blocking path to the amplifier input to provide a drive signal to be amplified and extracted at the amplifier output.

High frequency power source

High voltage, high frequency amplifier employing power transistors. The amplifier provides parallel ac signal amplification paths through each transistor and a single dc power path through the transistors in series. In one embodiment two FET's have their source electrodes connected to an input terminal and their drain electrodes connected to an output terminal so as to provide two parallel ac amplifying paths while blocking dc current flow. The drain electrode of the first FET is connected through an RF choke to source of dc operating potential, and its source electrode is connected through an RF choke to the drain electrode of the second FET. The gate electrode of the second FET is connected to ground. A single dc conductive path is thus provided between the source of operating potential and ground through the two FET's in series.

High frequency amplifier

High voltage, high frequency amplifier employing power transistors. The amplifier provides parallel ac signal amplification paths through each transistor and a single dc power path through the transistors in series. In one embodiment two FET's have their gate electrodes connected to an input terminal and their drain electrodes connected to an output terminal so as to provide two parallel ac amplifying paths while blocking dc current flow. The drain electrode of the first FET is connected through an RF choke to a source of dc operating potential, and its source electrode is connected through an RF choke to the drain electrode of the second FET. The source electrode of the second FET is connected to ground through a zener diode. A single dc conductive path is thus provided between the source of operating potential and ground through the two FET's in series.

High voltage, high frequency amplifier circuit

A high frequency amplifier utilizes series-connected transistors to achieve high voltage class C operation. High frequency input power is coupled to the gate of a first FET which is normally biased off. The source of a second FET is coupled to the drain of the first FET. The drain of the second FET, which forms the output of the amplifier, is coupled through a radio frequency choke to a supply voltage. The gate of the second FET is dc biased at about one half of the supply voltage. A capacitor coupled between the gate of the second FET and ground controls the level of high frequency power applied to the second FET. The amplifier can be operated at a dc voltage which is approximately equal to one half the sum of the individual breakdown voltages of the serially connected FET's.

High voltage, high frequency amplifier

Energy-saving circuitry for a rapid-start fluorescent lighting system includes a reactance-modifying capacitor coupled in series with first and second fluorescent lamps and includes a filament switch which is operative to conduct filament heating current during starting of the first lamp. The filament switch is coupled between filaments at opposite ends of the first fluorescent lamp and triggers to a low impedance state in response to the lamp starting voltage. A capacitor bypass switch can be coupled in parallel with the reactance-modifying capacitor to reduce the impedance of the series circuit during lamp starting.

Energy saving fluorescent lighting system

A light source includes a high pressure discharge lamp and incandescent filaments which provide illumination during the warm-up and hot restart periods associated with the discharge lamp. A current regulator, which provides dc power to the discharge lamp, draws sufficient current through one filament to energize the filament only during discharge lamp warm-up. A second filament provides illumination during the period after the occurrence of a momentary power failure or power transient which is required by the discharge lamp to cool down to its maximum starting temperature. A bimetal switch permits current flow through the second filament when the discharge lamp is above the maximum starting temperature. An electronic switch permits current flow through the second filament when a current sensing resistor senses a lack of current through the discharge lamp.

Instant-on light source

An electromagnetic discharge apparatus has a power coupling fixture which couples power to both ends of an electrodeless discharge vessel and produces a substantially uniform arc. Power can be coupled to the fixture from two high frequency power sources or can be coupled from a single high frequency power source by using a power divider. If power is coupled to the electrodeless discharge vessel from a single source, power transfer to the vessel is optimized when the electrical length of the circuit is an integral number of wavelengths. In an alternative embodiment, a second coupler is utilized in a conventional electrodeless light source to shape the electric fields and produce a more uniform arc.

Electromagnetic discharge apparatus with double-ended power coupling

Radioactive materials are used to assist in starting a discharge in an electrodeless light source. The radioactive emissions predispose on the inner surface of the lamp envelope loosely bound charges which thereafter assist in initiating discharge. The radioactive material can be enclosed within the lamp envelope in gaseous or non-gaseous form. Preferred materials are krypton 85 and americium 241. In addition, the radioactive material can be dispersed in the lamp envelope material or can be a pellet imbedded in the envelope material. Finally, the radioactive material can be located in the termination fixture. Sources of alpha particles, beta particles, or gamma rays are suitable. Because charges accumulate with time on the inner surface of the lamp envelope, activity levels as low as 10.sup.-8 curie are effective as starting aids.

Radioactive starting aids for electrodeless light sources

An electrodeless light source having a termination fixture adapted for connection to a high frequency power source has an electrodeless lamp with a self-contained ultraviolet excitation source and a means for coupling power to the electrodeless lamp. The electrodeless lamp includes a main lamp cavity and an exciter lamp cavity within a single envelope. When power is applied to the fixture, the exciter lamp cavity emits ultraviolet radiation which assists starting of the arc discharge in the main lamp cavity.

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Needham, MA, United States of America

Robert J Regan