Abstract: Active noise control for use by individuals using magnetically coupled hearing aids is realized by generating a true representation of the handset input signal, which is employed to drive a separate external field coil. The external field coil is positioned between the handset receiver and the handset acoustic output ports so that it is in close proximity to a user's ear cavity and, hence, to the magnetically coupled hearing aid. Also, in some embodiments of the invention, a magnetic shield is employed between the handset receiver and the external field coil to inhibit the magnetic leakage field from the receiver element from mixing with the magnetic field from the external field coil.

Abstract: Full channel service is obtained over a modified ISDN BRI interface by emulating at least one central office (CO) station terminal which provides access to a voice channel over a single digital subscriber line DSL for user station terminals whether or not they are ISDN BRI compatible. To this end, an interface is provided for the DSL that emulates an ISDN BRI CO station terminal and acts like a facility to user station terminals. More specifically, a plurality of CO station terminals are emulated on a single multi-point passive bus terminating the single DSL. Each of the emulated CO station terminals presents to the CO switching office the appearance of being a CO station terminal. The emulated CO station terminals are configured such that CO features are accessible. Information from the emulated CO station terminals is mapped into existing system structures where such structures are available and compatible with the information from the emulated terminal.

Abstract: A unitary housing made from an acoustically-opaque, resilient material is employed with a microphone element to form a directional microphone assembly. The microphone element includes a diaphragm which moves under the influence of sound pressure applied to its opposite surfaces to generate an electrical signal which is proportional to the differential sound pressure. The unitary housing includes a first acoustically-transparent channel for communicating sound pressure from a first port in the unitary housing to one surface of the diaphragm, and a second acoustically transparent channel for communicating sound pressure from a second port in the unitary housing to the other surface of the diaphragm. In an illustrative embodiment, the unitary housing comprises a unitary small "boot" having a surface including the ports for coupling acoustic energy to the acoustic channels, an inner chamber for housing the microphone element and a predetermined opening in a surface of the boot for accessing the inner chamber.

Abstract: A loudspeaker system which can be utilized with laptop PCs employs a loudspeaker enclosure having a unique shape which can easily be mounted to the back of a display of the laptop PC and also be easily removed for storing and/or transporting. Additionally, the enclosures of the loudspeaker system have been designed to allow the physical coupling of them together into a compact package so that they can be easily stored and/or transported, for example, in a briefcase for use during transit or at a remote location. This coupling of the loudspeaker enclosures is realized by employing a loudspeaker enclosure which is in the form of an "L-shape". Consequently, the loudspeaker enclosures can be placed upon each other and locked into place forming a relatively small compact package.

Abstract: A system for creating still image or video collections for guests of amusement parks and the like a) identifies individuals by a unique tag assigned to the individual, b) automatically records the images of the individuals while they are at various attractions, c) collects the images over a communications network, d) arranges the images in a collection, and e) presents a personal set of collected images to the guest. For example, cameras may be located throughout an amusement park. Each guest is associated with a unique identifier. This identifier may be contained within a readable tag, e.g., a card, badge or pendant. Tag readers identify guest when they are at a particular location and provide identification and location information to a control system. A communications network is used to interconnect the cameras, tag readers, control system and image recording devices. The control system controls the recording and storage of the appropriate image(s) associated with that guest.

Abstract: A telephone ringing system in which one or more user-selected sound segments are received using the microphone portion of a telecommunications instrument, stored in digital or analog form, and audibly reproduced using the loudspeaker portion of the telecommunications instrument when a ring signal is detected to provide a distinctive, personalized indication of an incoming call.

Abstract: A low-cost monitor includes two comparators which are adapted to form a window comparator which frames a laser transmitter's normal range of operation. An apparatus for generating an amplified back-face-monitor voltage corresponding to the laser transmitter's optical output power level is coupled to the window comparator. A reference voltage is also coupled to the window comparator which defines the upper threshold of the normal operational range. A controllable variable voltage source is coupled to the window comparator and is used to define the lower threshold of the normal operating range, where this lower threshold has two associated threshold values as described above. The lower threshold is initialized to the first threshold value which corresponds to an end-of-life operating state of the laser transmitter.

Abstract: An optical monitor tap in fiber optical amplifiers is achieved in a configuration with internal input signal monitoring taps, in accordance with the principles of the invention, by placing the tap some distance into the actual optical amplifier active fiber. This allows the system to minor the integrity of the amplifier without impairing the quality of the associated signal. In an illustrative embodiment of the present invention, the amplifier is generally comprised of a long piece of rare-earth material doped fiber to which a fiber optic pump source is coupled via a wavelength divisional multiplexer (WDM) coupler. The tap is placed at some distance from the input of the fiber amplifier. The distance should be small enough such that there has been amplification of the signal but not so much as to have the signal saturated or compressed.

Abstract: The problems associated with slow timing recovery in an ATM receiver are overcome by detecting the transmission rate of a received bit stream and periodically detecting the transmitted Enc.sub.-- CR values, which are used to calculate additional estimated clock reference (Est.sub.-- CR) values between the actual transmitted Enc.sub.-- CR values. The Est.sub.-- CR values are then used along with the actually received Enc.sub.-- CR values to generate a phase locked loop (PLL) error signal (TC.sub.-- ERROR), wherein the PLL is caused to converge more rapidly. In one embodiment, the TC.sub.-- ERROR values are generated for each received cell or packet instead of only for each received Enc.sub.-- CR value and, consequently, timing recovery is significantly speeded up. Additionally, the Est.sub.-- CR values can be adjusted to minimize the effects of lost cells, as well as, drift in the transmission rate.

Abstract: An improved Broadside SOG microphone assembly is realized by employing a microphone assembly having at least three ports arranged in a non-colinear fashion with the at least three ports defining and being in a "gradient" plane and with both outer adjacent differential pair of ports aligned in a direction substantially toward a prospective talker's lips. Thus, the inner port(s) is always closer to the prospective talker's lips. Each outer differential pair of ports forms a dipole which yields a high spatial gradient and, hence, higher speech sensitivity since they are pointed substantially toward the prospective talker's lips. Just as important, as the prospective talker's lip position relative to the microphone varies, this alignment of each outer differential pair of ports will result in the least change in the dipole sensitivity and, therefore, the lowest Broadside SOG microphone position sensitivity.

Abstract: A power supply for regulating energy delivered to a power consuming apparatus operating at low current levels includes a power source comprising at least one battery for generating an output voltage greater than a desired operating level. The power supply further includes a voltage regulator circuit comprising a light emitting diode (LED). The light emitting diode, which is preferably configured as a gallium arsenide diode, operates at a substantially constant voltage within a current range of between 10 to 25 micro amps. As a result, reliable and economical voltage regulating circuits can be constructed with substantially improved performance, as compared to circuits utilizing zener diodes as the active voltage regulating component, at the very low current levels required for such applications as line powered telecommunication devices.

Abstract: Acoustic echos are canceled by employing a first echo canceler having a comparatively short first impulse response synthesis capability which is connected between a transmit path and receive path for generating a first error signal and for canceling echo signals in the transmit path, and at least a second echo canceler having a comparatively long second impulse response synthesis capability connected in parallel with the first echo canceler between the transmit and the receive path. The second echo canceler is supplied with the first error signal from the first echo canceler and is adaptively operating simultaneously with but independent of the first echo canceler to further cancel echos in the transmit path. More specifically, the first echo canceler is intended to capture the direct path acoustic echo and any early arriving echos that are stable which are not time yawing. Since the direct path acoustic echo and the stable early arriving echos are not time varying, the adaptive adaptation rate, i.e.

Abstract: A graphical user interface, i.e., multimedia communications application program, for setting up and handling a multimedia call is disclosed that employs realistic metaphors of real life face-to-meetings in setting up and handling a multimedia call to establish a virtual meeting which is automatically reconfigured in response to user action. This is realized by taking advantage of prospective virtual meeting participants' already existing knowledge of how real life face-to-face meetings operate. To this end, the multimedia communications application program enables the virtual meeting participants through direct manipulation of the realistic graphical metaphors to establish a realistic virtual meeting room which is displayed on the screen of their workstation monitor. The virtual meeting room includes a table and chairs arranged in a realistic manner in the virtual meeting room.

Abstract: A packet-based telecommunications architecture is disclosed that, like virtual-circuit networks, preserves the sequential order in which packets are presented to the network, but does not require node-by-node call set-up or tear-down, unlike virtual-circuit networks. Further, the packet switches which compose the architecture can be more simple than those used in datagram or virtual-circuit networks. An illustrative embodiment of the present invention comprises determining the topology of a network of packet switches that are connected by communication links, associating at least two names with at least one of the packet switches, and populating the router tables in the packet switches so that for each name the packet switches and communication links form a elemental network with the topology of a sink tree with the named packet switch at the root of the tree.