Abstract: A circuit for communicating digital data is disclosed. The circuit can connect with up to 12 digital data lines (L0 through L11) for communication under a T1 or E1 standard. Control processor 36 selects the appropriate communication standard to be used by each framer/line interface processor F0 through F11, and communicates these over control bus 38. Control processor 36 also selects an appropriate line impedance for each line input/output circuit IO0 through IO11, and communicates this information over control bus 38 to control logic 34. Control logic 34 uses control lines 39 to electronically select the impedance for each line input/output circuit IO0 through IO11. Circuit 22 can be easily configured or reconfigured to receive data with different data formats and line impedances. In one preferred embodiment, each framer/line interface processor and line input/output circuit can be independently controlled, such that multiple communication formats can be simultaneously processed by circuit 22.

Abstract: An audio interface is coupled to received a music signal and a microphone signal. The music signal and a volume control signal are combined in a multiplier to produce a volume adjusted music signal. In response to an input signal from a user, the volume control signal is gradually changed in predetermined increment levels. Thus, the multiplier gradually changes the audible volume in these predetermined increment levels. The resulting music and microphone signal are stored in corresponding partitions of a single memory, and thereafter provided to a mixing circuit. The mixing circuit combines signal samples read from the memory to produce four output signals each containing first and second channel samples. The resultant 8 channel samples are gated in a formatter with respective channel mute signals which, when asserted, effectively mute their corresponding channel sample.

Abstract: A combined conversation mirror and intercom is mounted in a mirror frame pivotally mounted to a vehicle accessory, such as an overhead console. The frame is movable between an unobtrusive stored position and an extended use position located such that the vehicle operator can see mid or rear seat passengers, and, similarly, the mid or rear seat passengers can see the vehicle operator. In a preferred embodiment of the invention, an electrical switch is coupled between the mirror frame and vehicle accessory such that movement of the mirror frame actuates the switch for powering the intercom circuit.

Abstract: An apparatus for discriminating between signals produced by a desired acoustic source and an undesired acoustic source includes: a first microphone disposed at a first distance from the desired acoustic source; at least a second microphone disposed at a second distance from the desired acoustic source; a proximity estimation block configured to utilize signals form the first microphone and second microphone to produce a signal representing an estimate of the proximity of the desired acoustic source; and a variable gain block configured to adjust the gain of an output signal from at least one of the microphones by utilizing the estimate of the proximity of the desired acoustic source.

Abstract: A load coil device for a twisted pair telephone line is disclosed. The device is for compensating distributed stray capacitance in telephone lines that are longer the 18,000 feet. Typically, a load coil device would be inserted in the line every 6,000 feet. The device includes two windings, each winding to be connected in series with one of the conductors of the telephone line. The windings flatten the frequency response of the line in the voice frequency (VF) band. The device further has a capacitor connected in parallel across each winding. The values of the capacitors are chosen to provide a low impedance path that bypasses the windings for frequencies in the range of 20 kHz to 1.1 MHz. The device is particularly useful for long telephone lines over which high speed services such as asynchronous digital subscriber line (ADSL) are to be provided.

Abstract: A CD player and three audio storage devices are coordinated using an interface(FIG. 1) which allows for a unique process of audio arrangement in which continuous intervals of audio are programed to be played from a CD in a specific order, each having a specific tempo and volume at which it is assigned to play. The process of forming an audio arrangement includes auditioning continuous intervals of audio directly from a CD in order to locate the precise position of desirable audio and then connecting these desirable intervals of audio so that each may be transmitted by this invention with a specific amount of timing with respect to the interval of audio that preceded it. After forming a program that specifies an audio arrangement, the CD player and the three audio storage devices can be used to further connect, blend, overlap, and otherwise mix the continuous intervals of audio read from one or several compact discs.

Abstract: A sound image localization apparatus comprises a signal source for outputting an audio signal; a localization angle input unit for receiving an angle of a sound image to be localized; a coefficient control unit for receiving sound image localization angle information from the localization angle input unit, reading coefficients from a coefficient memory in accordance with the information, and outputting the coefficients; first, second, and third multipliers for multiplying the audio signal output from the signal source by using first, second, and third coefficients output from the coefficient control means, respectively; a first signal processing unit for receiving the output from the second multiplier, and processing it by using a filter having a predetermined first frequency response; a second signal processing unit for receiving the output from the second multiplier, and processing it by using a filter having a predetermined second frequency response; a first adder for adding the output from the first multi

Abstract: The present invention relates to systems and methods for providing a “lifeline” service to a VoDSL customer despite an electrical power outage or integrated access device failure at the customer premise. A bypass function is implemented in an integrated access device at the customer premise to provide the lifeline service. The bypass function is preferably a relay, which can be automatically activated to provide the lifeline service under various conditions. The bypass relay, working in conjunction with systems in the central office and the regional switching center allows the customer to obtain an active telephone line during power outages or integrated access device failures. Electrical power is also supplied to the customer's premise from the central office, thereby allowing the customer to use a telephone line in the traditional manner. The present invention can further be implemented for any number of customers and telephone lines.

Abstract: A device for echo attenuation in a digital transmission system comprises an impedance replica of the transmission path. The impedance replica consists of a terminating resistance replica, a transformer replica, and a transmission line replica. The device may further comprise a bridged tap replica. The transformer replica and the bridged tap replica are provided as on-chip components. The main transformer inductance replica and all components of the bridged tap replica are variable and may be set by software control.

Abstract: A voice-switching device for use in a telephone terminal which applies an optimal amount of switched loss to a plurality of distinct receive transducers. The voice-switching device detects speech signals on the transmit and receive paths to determine a mode of operation. Based on the mode of operation the device applies optimal amount of loss to the transmit path and each output path separately. This system eliminates excessive attenuation of non-dominant receive transducers as well as optimizes the transition time from active to quiescent mode for all receive transducers.

Abstract: The present invention teaches a system for improving the clarity of a voice spoken within an enclosed space. The system comprises a first microphone, positioned at a first location, for receiving the audible communication and for converting the audible communication at the first location into a first audio signal. The system also comprises a loudspeaker for receiving the first audio signal, and for converting the first audio signal into a first reproduced audible communication, the reproduced audible communication also being fed back and received by the first microphone and converted with the audible communication into the first audio signal.

Abstract: A sound processing apparatus includes a plurality of microphones spaced apart from each other, each microphone producing electrical signals representative of sound signals incident thereon. The sound processing apparatus also includes a signal processing unit that produces a specific direction sound signal by processing the electrical signals according to a specific sound direction. The plurality of microphones can be positioned about a periphery of a computer display, and adaptive beam forming techniques can be employed to provide a directional input sound signal for use in sound processing.

Abstract: An improved thermal design for passively cooled telecommunication repeater housings for use with wire transmission in the local loop outside plant is achieved by replacing the known convection based heat transfer designs with a design based on solid thermal conduction. A thermal chassis includes thermal collection, transfer and distribution members that collect the repeater modules' waste heat through respective thermal interfaces, transfer the waste heat along respective thermal conduction paths to the environmental enclosure, and then distribute the waste heat over a substantial portion of the enclosure's available surface area to form an enlarged thermal interface for convectively transferring the waste heat to the ambient air. Heat transfer is further improved by expanding the enclosure's external surface area and fabricating the distribution members so that they are in permanent and intimate thermal contact with the enclosure's expanded surface area.

Abstract: Active noise reduction headphones for audiometry where the earphone portion of said headphones has a cavity volume greater than 6 cc and including an acoustic-electric sensing means and an electro-acoustic transducing means which are used cooperatively and which has additional passive noise control means in the form of a circumaural seal around the ear for improving high frequency noise control performance, the headphone having a summing junction for combining the active noise reduction signal and an audiometry test signal.

Abstract: Methods and devices for reducing undesired signals in a communication environment. At least two distinct composite signals (X1 and X2) are transmitted from a first communication environment (260). A noise coefficient of the first communication environment (260) based on the at least two distinct composite signals (X1 and X2) is calculated. At least two noise canceling signals based on the noise coefficient are calculated. The at least two noise canceling signals are added to an incoming signal (Y3) from a second communication environment (280) to produce at least two combined signals. The at least two combined signal are transmitted into the first communication environment (260).

Abstract: In a telephone system having multiple working metallic interface units, a method and a structure provide protection by assigning to each metallic interface unit a partner unit, which is another metallic interface unit. Under this arrangement, when a failure occurs in a working metallic interface unit, its partner unit switches the ring/tip input signals of the failed metallic interface unit to a protection bus. A standby or protective unit then takes over by receiving the rerouted tip/ring signals from the protection bus. The failed working unit can then be removed from the shelf without disrupting service.

Abstract: The line interface circuit of a modem to be connected to a standard RJ11 jack of a digital PBX (Private Branch Exchange) is used along with software routines resident in the modem to detect the presence of a PBX connected to the modem. Upon going off-hook, the modem, by the software routines, determines whether the connection will harm the interface by one of several software routines. If it appears that the interface circuit may be damaged because a PBX line is present, the modem is instructed to go on-hook (hang up), or if the connection is not harmful to the interface, alerts the user that the modem is connected to a wrong jack.

Abstract: A hand microphone and an adaptor module form an assembly which is a peripheral device for a personal computer. The hand microphone is used to control dictation functions to be carried out by the PC. Two separate analog control signal channels are output from the hand microphone and applied, respectively, as X- and Y-axis inputs for the game port on the PC. Control signals carried in the two signal channels are generated by actuating control switches mounted on the hand microphone.

Abstract: In a method and apparatus for producing constant sound pressure level in a hearing aid, a microphone, a receiver and a signal processing unit are provided. A switching unit produces constant sound pressure levels. The switching unit has an envelope generator for producing an envelope value of a signal value to be processed and a divider for calculating the ratio of the signal value and the envelope value as the signal to be output or further processed.

Abstract: A delay and attenuation compensation-based BSS technique for source selection and noise reduction is provided for speech recognition applications. The undesired signals are attenuated in every situation and from every direction as much as possible. For this purpose, the direction of the input signals is determined. Depending on the direction of the undesired signals, the internal delay between the microphones is calculated. This internal delay is then used in subtracting the microphone signals from each other. Therefore, the invention gives not only a good directionality on average, but the best directionality for every listening situation. Furthermore, the channel selection problem is solved in conjunction with the BSS technique.