Abstract: In a radio frequency identification communication system, a communication protocol advantageously controls communication between an interrogator and one or more identifying labels or read/write tags. This protocol is configurable in two modes in which a read/write tag can be expected to operate. In the first mode, a rapid transfer of a limited amount of data takes place between the interrogator and one or more tags. In the second mode, a slower or less time critical transfer of a large quantity of data in a packet format takes place. In this second mode, a communication to the other tags causes these tags to remain "silent" so that they do not corrupt the data transfer in progress. The interrogator automatically determines the quantity of data and the correct mode in which to operate. Either mode can be initiated on successive communication periods by the communication protocol.

Abstract: A power-conserving, linear and broad band RF amplifier, suitable for use at more than one band in the ultra-high frequency regions allotted to radiotelephone transceivers, employs an emitter-follower output transistor to deliver the nominal 1.0 milliwatt RF power to a single-ended load from a low voltage battery, typically 2.7 v. dc, without the use of output coupling transformers. The amplifier receives only a small differential input signal from the preceding mixer or multiplier stage having a typical peak-to-peak magnitude of 0.3 v. The differential input signal is applied to the emitters of a pair of transistors whose bases are interconnected, one transistor of which (B6) is diode-connected in a current-mirror configuration and the other (B5) of which is configured in a common-base connection with emitter degeneration. The signals are summed at the collector of the common-base transistor to deliver a substantial voltage swing, illustratively 1.

Abstract: Digital information is encoded in the video portion of a television signal such that "n" (n is an integer) bits of the digital information are carried by each successive frame in a group of frames. The digital information is encoded by modulating a carrier signal, using, for example, either amplitude shift keying (ASK) or frequency shift keying (FSK), and the modulated carrier is then added to the video signal selectively, only in portions of the television program that (a) are not likely to be perceptible by a viewer, and (b) are of sufficient intensity to transmit the data. The video signal including the encoded digital data, may be transmitted, in real time, to a television receiver, or recorded for later playback.

Abstract: An optical isolator includes an optical isolator unit including a main polarization discriminator in concatenation with a Faraday rotator, and an auxiliary polarization discriminator disposed in series with the optical isolator unit. One of the polarization discriminators initially divides an applied optical signal propagating in a forward direction along a reference axis into two polarized signals subsequently experiencing polarization dispersion and differential transverse deflection, while the other polarization discriminator eventually eliminates the polarization dispersion. Tile auxiliary discriminator includes a plate of a uniform thickness inclined at a tilt angle with respect to the reference axis selected so that the transverse deflection difference incurred during the passage through the one polarization discriminator is eliminated in the other polarization discriminator. This facilitates achieving very low polarization dependent loss in the isolator.

Abstract: An electrical conductor of the type known as a power adapter for connecting a power supply to a coaxial cable comprises a central metal conductor having a known type coaxial cable type coupler at one end and a flat plate terminal at the other end. The conductor is surrounded by a tubular insulator surrounded, in turn, by a tubular metal sleeve. At the one end of the adapter, the metal sleeve terminates in a threaded metal tube which surrounds, in electrically spaced apart relation, an axially extending portion of the central metal conductor either in the form of a solid plug extending beyond the metal tube or a hollow receptacle terminating inwardly of the end of the metal tube. Intermediate the two ends of the central conductor, the sleeve contains a plurality of axially extending flat surfaces spaced circumferentially around the sleeve. Two power supply wires are connected, respectively, to one of the sleeve flat surfaces and to the central conductor plate terminal.

Abstract: In a decision-forest classifier in accordance with the invention, a decision forest including multiple decision trees is used to classify "seen" training data and "unseen" data. Each individual tree performs an initial classification based on randomly selected subsets of the data. The classification outcomes by the individual trees are combined using a discriminant process in the decision-forest classier to render the ultimate classification decision.

Abstract: A technique for the enhancement of degraded document images to improve their display quality characteristics and image recognition accuracy. Images believed to be representative of the same symbol which occur in different positions over a image source (e.g., a facsimile page) are clustered together. Using the symbols within a particular cluster, an average character image outline for that cluster of symbols is derived and thereafter used to refine the matching of symbols within the cluster and to determine a final representative symbol for that cluster. The final representative symbols from the various resulting clusters are then used to replace all matching images throughout the image source. Advantageously, the display quality and recognition accuracy of the image source is enhanced after application of the present invention due to the resulting improvement of the images in the image source.

Abstract: Apparatus, system, and method is disclosed for digitally processing a signal for reduced distortion and frequency deviation. The digital processor involves increasing the sampling frequency of a digital signal prior to a non-linear operating stage. The processed signal is then passed through a low pass filter prior to being down-converted to the initial sampling frequency. Thus, a signal can be digitally processed for reduced distortion as well as reduced frequency deviation.

Abstract: In accordance with the invention, the index of refraction of a region of a glass body is selectively increased by treating the glass with hydrogen or deuterium, heating the hydrogenated glass to a temperature in excess of 500.degree. C., permitting the glass to rapidly cool below 100.degree. C. and exposing the region to UV radiation, preferably in the range 300 nm to 400 nm. The result is an increase in the refractive index of the irradiated region. Absorption is via a GODC band at 330 nm believed to result from a singlet to triplet transition. This band is about 1000 times weaker than the commonly used band at 240 nm. This process can be used to make and adjust a variety of optical waveguide devices such as photoinduced Bragg gratings and long period gratings.

Abstract: An optical coupling system couples an optical fiber to an optical semiconductor device. A beam expander is disposed within the optical semiconductor so as to receive light from or transmit light into the optical fiber. The coupling is accomplished by disposing a layer of an index matching gel or epoxy on either surface of the semiconductor optical device or the end portion of the optical fiber and another layer of an antireflective material adjacent to the index matching gel or epoxy. The semiconductor device may include an array of optical devices, each coupled to a corresponding optical fiber via the arrangement that comprises the index matching gel and the antireflective material. The semiconductor device may also include an array of waveguides, each configured to receive light from a corresponding optical fiber.

Abstract: A multiplier generates an array of partial products. The partial products are reduced in the more significant side of the array assuming a carry-out from the less significant side of the array as taking on a first state to produce a first set of reduced products. The partial products are also reduced in the more significant side of the array assuming a carry-out from the less significant side of the array as taking on a second state to produce a second set of reduced products. Both sets of reduced partial products are generated in parallel with the carry-out from the least significant side. The first set of reduced products are selected as the reduced products of the more significant side of the array when the carry-out from the less significant side of the array takes on the first state. The second set of reduced products are selected as the reduced products of the more significant side of the array when the carry-out from the less significant side of the array takes on the second state.

Abstract: Using designated special telephone numbers each associated with a particular language to provide rate information by a telecommunication switching system that responds to those special telephone numbers. When a caller calls one of the special numbers, the caller is requested in the correct language to enter the desired destination telephone number; and in return, the caller receives the cost for making a call to that number. If the caller wishes to place the call, the system automatically places the call. If the decision is made to place the call, an option allows the caller to specify the maximum amount of money they will spend. After this maximum amount of money is met, the system automatically disconnects the call. The system gives a warning at some predetermined interval before the call is disconnected.

Abstract: A bridging clip for providing electrical connection between adjacent terminals; in particular, terminals having wire wrap connection wounded on the tail end of the terminals. The bridging clip comprises two integrated and electrically conductive walls, creating a groove therebetween for engaging the wire wrap connection of adjacent terminals. Along each wall is at least one corresponding cut-out, which are indented into the groove for independently engaging the tail ends of adjacent terminals. Multiple electrical contact is achieved by the walls and cut-outs of the bridging clip. The bridging clip is made of a resilient material which provides positive electrical contact and allows repetitive use.

Abstract: Briefly, in accordance with one embodiment of the invention, a bootstrap circuit comprises a pair of drivers coupled together so as to form a bootstrap node and a bipolar transistor coupled to the bootstrap node. A method of using a bipolar transistor in such a bootstrap circuit comprises the step of applying a voltage signal to the input ports of the drivers, the voltage signal having a magnitude sufficient to activate the bipolar transistor.

Abstract: For use in a distributed power system having first and second power processing modules, a power processing module for, and method of synchronizing an operation of the second power processing module with the first power processing module and a power converter employing the power processing module or the method.

Abstract: A gain-switched optical selector is realized by employing an optical rare earth-doped fiber optical amplifier as the switching element per se. Each of the optical rare earth-doped optical amplifiers acts as an ON/OFF switch. Also, the gain-switched optical selector of this invention is a natural fit into today's optically amplified optical communication systems. In one embodiment, this is realized by employing a pump select circuit in conjunction with a plurality of pumps and a plurality of corresponding rare earth-doped fiber optical amplifiers. The particular pump and corresponding optical amplifier are selected by use of a monitor arrangement to determine which signal is to be selected and routed to an output. In another embodiment, a so-called tuned pump arrangement is employed in conjunction with a plurality of filters and a corresponding plurality of rare earth-doped fiber optical amplifiers.

Abstract: A wireless repeater comprising a first antenna for receiving a first signal from a wireless terminal and for transmitting the first signal along a first path; a second antenna for receiving a second signal from the wireless terminal and for transmitting the second signal along a second path; a summing circuit for receiving the first signal from the first path and the second signal from the second path, for summing the first signal and the second signal to form an aggregate signal, and for outputting the aggregate signal along a third path; a delay in the second signal that makes the second signal path longer than the first signal path; and a third antenna for receiving the third signal from the third path and for transmitting the third signal.

Abstract: A split reciprocal polarization switch (SRPS) for use in constructing high performance switching devices used in fiber optics. The SRPS allows selective changes in the polarization of one or the other of two optical rays passing therethrough along first and second bi-directional ray paths of the SRPS so that they emerge therefrom with the same polarizations. The SRPS includes a switching section for selectively changing the optical polarization of optical rays according to a selected state of the switching section, and a split section including a first and second sections having different polarization changing characteristics.

Abstract: Systems and methods that include a homotopy technique are employed to find a DC operating point of large-scale, transistor-based, nonlinear circuits?, allowing such circuits to be designed, tested and manufactured!. The systems and methods use arclength continuation together with a new two-phase embedding of .lambda. into equations describing the circuits.

Abstract: Apparatus for steerable nulling of a radiation pattern of a main lobe and at least one side lobe with at least one null point produced by an antenna array of n elements relative to wideband radio frequency signals having a carrier wave modulated with pulse signals, while receiving the radio frequency signals from, or transmitting to, a desired station and at least one interfering station. An interference rejection processor (IRP) that has n inputs, each connected to a respective element of the antenna array, is connected between the receiver or transmitter and the antenna array. The IRP steers the effect of the antenna radiation pattern such that the at least one null point substantially corresponds to the reception of the radio frequency signal from, or transmission to, the interfering station. The antenna array has an aperture bandwidth, E, such that the IRP is implemented using only phase delay of the radio frequency signals to steer the radiation pattern.