Abstract: Compression of signals is achieved through a simple decision of whether or not to encode certain frequency bands; not how well to encode all of the frequency bands. Based on the input signal and on a preselected perceptual model, a "just noticeable difference" (jnd) noise spectrum is computed. This spectrum is applied to a selector where it is used in the decision to select a chosen number of frequency bands of the input signal. The bands selected are the bands with the greatest energy relative to the jnd energy in the same band. Each of the selected bands is encoded and transmitted to the receiver. Both analog and digital realizations are presented.

Abstract: A field programmable gate array (FPGA) with a programmable function unit (PFU) that includes a look-up table (LUT) for implementing a plurality of functions including first and second RAM cells, and a programmable switching device dedicated to coupling and decoupling the RAM cells. The first and second RAM cells are coupled to respective first and second read/write ports. The RAM cells function individually as single-port RAM cells when decoupled by the switching device. However, the RAM cells share data to function collectively as a dual-port RAM cell when coupled by the switching device. The dual-port RAM cell is accessible by both the first and second read/write ports.

Abstract: The present invention provides a method and apparatus in a data storage device of a data storage system under the control of a microprocessor for preventing a microprocessor stall upon the occurrence of a power failure during read/write operations. During normal operations, files are written to a first storage area of the data storage device where a first flag associated with each file is set when the writing of the respective file has successfully completed. Upon the occurrence of a power failure, a data storage device initialization routine is commenced upon reboot of the microprocessor. During initialization, an analysis phase is begun to generate sequences of events for at least those files not having the first flag set. The events comprise memory operations and associated data and are each re-executable upon interruption of its execution and before execution of another event without modifying results of a previous execution of the respective event.

Abstract: In a simultaneous voice and data communications system, a voice signal is added to a data signal before transmission over the public switched telephone network (PSTN). In particular, in every signaling interval, a signal point is selected for transmission as a function of both the voice signal and the data signal. Since the voice signal is effectively offset by the data signal, compandors normally found in the PSTN are not effective in improving the signal to noise ratio of the transmitted voice and data signal. Therefore, the voice signal is additionally companded in the transmitter before transmission over the PSTN. This additional companding by the transmitter improves the signal to noise ratio of the combined voice and data signal.

Abstract: Briefly, in accordance with one embodiment of the invention, a method of reducing the power consumption of a pipelined signal processor embedded in an integrated circuit (IC), after applying power to the IC, comprises the step of: applying a sufficient number of internally generated clock pulses to the pipelined signal processor so as to place at least one bus in the signal processor pipeline in a predetermined state. Briefly, in accordance with another embodiment of the invention, an integrated circuit comprises: a power-up reset circuit for a pipelined signal processor. The power-up reset circuit includes a counter and a digital signal oscillator. The digital signal oscillator and counter are coupled in a configuration so as to provide a predetermined number of clock pulses substantially in response to a power-up signal. The configuration is adapted to be coupled to the pipelined signal processor.

Abstract: A limit is placed on charges to be incurred on a telecommunications call. Normally, this limit is specified by the caller. The telecommunications network maintains a running tally of the charges being incurred and notifies the caller when the charges approach the limit. At that time, the caller may specify a new limit, simply disconnect, or be automatically disconnected when the limit is reached. Advantageously, callers can limit the charges on a particular call without having to be aware of the exact charging parameters for that call.

Abstract: An information system for automatically providing mobile vehicles with information related to their geographical location and to provide routing control information downloaded from a broadcasting or directed cellular call source includes a GPS receiver and associated data storage unit. A cellular packet data receiver is included to receive data with location markers from a transmission source. The data from the data storage unit and the received data with location markers is coupled to a controller module which includes stored program controls to select data relevant to the present geographical location and to provide centralized alerts and local readout in the mobile vehicle of this information.

Abstract: A wireless-enabled host electronic equipment includes a built-in antenna and special plug-in receptacles enabling a plug-in wireless communicator to interact with the host and to connect to the built-in antenna for wireless transmission and reception. In accord with the invention the plug-in arrangement is constructed to conform to a standardized plug-in arrangement, such as a PCMCIA standard and to provide additional plug-in capability in addition to the standardized receptacle which does not conflict with the standardized receptacle. The plug-in arrangement is configured to permit use of a plug-in for other purposes in the same standard receptacle.

Abstract: A wire guide and optical fiber storage spool assembly of this invention is adapted to engage with a patch panel housing optical fiber or conductive wire connectors. The wire guide has a substantially C-shaped pan with a gap through which can be laterally passed conductive wires attached to connectors of the patch panel. The first side of the C-shaped part has a locking member for releasably engaging the patch panel, while the second side of the C-shaped part has a slide for connecting the storage spool to the wire guide. Slide receptacles on the storage spool base releasably lock into engagement with the wire guides so that the storage spool cannot inadvertently be released from its supporting wire guides. The optical fiber storage spool base supports a spool about which can be wound optical fibers connected by connectors in the patch panel. To confine the optical fibers in near proximity to an outside surface of the spool, substantially L-shaped members are supported by the base and curve toward the spool.

Abstract: This invention relates to apparatuses and methods for aligning optical fibers housed in an optical fiber array with optical waveguides coupled to an optical integrated circuit (OIC) housed in an OIC assembly of a related invention. An apparatus of this invention includes a first micropositoner in which the optical fiber array is mounted, and a second micropositioner in which the OIC assembly is mounted. An adhesive is applied to one or both opposing ends of the optical fiber array and the OIC assembly, and the first and second micropositioners are manipulated to move the optical fiber array end in close proximity to the OIC assembly end so that the adhesive contacts the ends of the optical fiber array and the OIC assembly to form an optical fiber/adhesive/optical waveguide interface. One optical fiber, preferably toward one side of the optical fiber array, is selected and light from a light source, preferably a laser, is generated and supplied to the selected optical fiber.

Abstract: High-efficiency clock generator circuits having single or complementary outputs for driving capacitive loads. The clock generator has therein at least one pair of complementary FET switches, coupled between the output of the generator and power supply rails, and an inductor. The generator is operated at a frequency approximately equal the resonant frequency of the inductor combined with the capacitance of the load. Energy normally stored in the load and dissipated in the FETs as in conventional clock generators is instead stored in the inductor and returned to the loads for reuse.

Abstract: A system and method are disclosed for recognizing and routing telephone call activity involving a hearing or speech impaired person. A caller places a local, intra-LATA, or inter-LATA telephone call by adding a three digit prefix to a called party number (CPN); the prefix identifies the call as one in need of routing to an Operator Services for the Deaf (OSD) or Tele-communications Relay Services (TRS) center. The call is first routed to a switching network where a query is sent to a Universal Subscriber Data Structure database using the caller's Automatic Number Identification (ANI) and the CPN of the called party. The database responds with the caller's and the called party's profiles. Thereafter, the call is routed to an adjunct which connects the call to an appropriate OSD or TRS center, whereupon the conversation can be relayed between the hearing or speech impaired person and the voice party.

Abstract: A security system controlling access to a resource is arranged to operate such that when an attempt to access a resource using a password or PIN fails, the time interval "t" that must elapse before a subsequent attempt at access can be successful, is incremented. By making the increments increasingly large (illustratively, an exponential function of the number "n" of unsuccessful attempts), repeated access attempts by hackers or other unauthorized users is discouraged, because they simply cannot wait the time needed to make a large number of trial and error attempts. On the other hand, valid users, while experiencing a delay prior to access, are nevertheless able to gain access, rather than being completely "lockedout". This approach is a better compromise between access control and denial.

Abstract: An optical isolator comprises a non-reciprocal rotator disposed between a pair of birefringent wedges, an input wedge and an output wedge. In order to reduce walk-off between the ordinary and extraordinary rays at the output of the isolator in one embodiment, the input signal is made incident on the input wedge at an angle above the normal to the wedge. At a particular angle related to various parameters of the isolator the relative walk-off can be reduced to essentially zero. In another embodiment, the input angle and various isolator parameters are mutually adapted so that the ordinary and extraordinary rays intersect within the isolator.

Abstract: This invention involves a vertical cavity surface emitting laser ("VCSEL") having a Group III-V semiconductor epitaxial mesa structure with an electrically insulating sidewall located on the mesa's sidewalls for confinement of the optical radiation generated in the laser. A suitably doped Group III-V epitaxial layer or a layer of insulating material such as silicon dioxide acts as the insulating sidewall layer. Advantageously, the structure has a self-aligned ohmic contact layer located everywhere on the top surface of the epitaxial mesa structure.

Abstract: A passive optical network architecture is disclosed for application in a local loop telephone environment. A local digital switch transmits an optical signal bearing information downstream over an optical fiber to the terminal equipment of a group of subscribers. This transmitted optical signal comprises light at a number of different wavelengths, i.e., it is a wavelength-division multiplexed signal, where each subscriber is associated with a particular wavelength of light. Each subscriber's terminal equipment detects that portion of the transmitted optical signal that exists at its assigned wavelength and thereby recovers the information sent by the local digital switch for that subscriber. However, a fraction of this detected optical signal is then remodulated by the subscriber's equipment with the subscriber's upstream information and returned to the local digital switch. As a result, no optical sources exist in the subscriber equipment in this optical network architecture.

Abstract: A method for sending and displaying customized video images with telecommunications devices is disclosed. In one embodiment of the invention, a video-caller identification scheme is described in which in-band signalling is used to transmit video data.

Abstract: Critical placement and lengths of dispersion-compensating fiber maximize capacity in upgraded in-ground optical fiber communication systems. Higher per-channel bit rates in single-channel systems and in WDM systems are permitted.

Abstract: A graphical password arrangement displays a predetermined graphical image and requires a user to "touch" predetermined areas of the image in a predetermined sequence, as a means of entering a password. The password is set by allowing the arrangement to display the predetermined areas, or "tap regions", to a user, and requiring the user to position these tap regions in a location and sequence within the graphical image, with which the user desires the password to be set at. These "tap regions" are then removed from the display, leaving the original image by itself. The arrangement then waits for an entry device (user) to select the "tap regions", as described above, for possible access to a protected resource.

Abstract: A smart card that is responsive to a list of items with individual prices that are received from a point of sale (POS) terminal during an individual transaction to automatically insert these items into expense categories. A personal computer later retrieves these categories and associated information and inserts the information into a spreadsheet. The microprocessor in the smart card relies on stored tables defining commonly used item designations and a table that defines definitions based on an ongoing learning process by the microprocessor in conjunction with the personal computer.