Abstract: An on-board monitoring system for an automotive emission catalyst [having] has (i) a test chamber remote from the automobile's engine exhaust gas stream; (ii) [means] apparatus for supplying the chamber with sampled exhaust gases sequestered from said stream; (iii) a single hydrocarbon sensor exposed to the exhaust gas in the chamber to render a signal responsive to the concentration of hydrocarbon in the chamber; and (iv) [means] apparatus for comparing the sensed signal with a reference signal, and, if a predetermined difference is exceeded, the catalyst is indicated as faulty. [Means (ii) may have] Apparatus (ii) has a supply channel interconnected between the chamber and the gas stream upstream of the catalytic converter, a supply channel independently interconnected between the chamber and the gas stream downstream of the catalytic converter, and valve [means] apparatus for permitting flow-through of no more than one channel to said chamber at any one moment, preferably cycled at a certain frequency.
Abstract: A security device for protection against pickpockets comprising a clamp intended to be releasably clamped on a top edge of a pocket and connected to a card-size casing by a flexible connecting element is disclosed. The card-size casing is adapted to be received in a compartment inside a purse which, in turn, is received in the pocket such that pulling the purse out of the pocket causes a lock bolt on the clamp to tightly secure the clamp to the pocket. A pull rod is movably fastened in the casing and connected to the flexible connecting element to trigger an alarm circuit when the casing is pulled outwards.
Abstract: A cordless communication system includes a plurality of cordless communication devices, a plurality of connection units which couple the cordless communication devices and communication lines, and a control unit which controls connections between the connection units and the cordless communication devices. The control unit includes a retrieval range specifying part for specifying idle channel retrieving ranges within which connection units which are idle respectively retrieve idle channels so that the connection units which are idle share a retrieval procedure for retrieving idle channels from all the channels, and a control part for controlling the connection units so that the connection units which are idle retrieve idle channels within the idle channel retrieving ranges specified by the retrieval range specifying part.
Abstract: In an active control noise-cancelling muffler system, a substantially complete acoustic and mechanical decoupling of the noise-cancelling signal pipe from the gas exhaust pipe is achieved. The noise-cancelling signal delivery pipe is physically isolated and separate from the gas exhaust pipe, and is mounted separately. The outlet end of both pipes are essentially coplanar. Using pressure sensors on the tubes, the system also accurately and continuously electronically replicates the mixing of the exhaust noise and the noise-cancelling acoustic energy that goes on in the space immediately beyond the two outlets. This electronic signal is a useful alternative for a direct measure of the resultant two acoustic waves when they mix in the space beyond the tube outlets, and allows the system to continuously estimate the degree of success of noise cancellation without having to measure it directly when impractical.
Abstract: A system and method for providing Feature Group B or Feature Group D access to the public data network for effecting point of sale transactions such as credit card authorization. The credit card authorization device includes a modem and auto-dialing mechanism which is connected by a station line to an originating central office switch. The originating central office switch is connected via Feature Group B or Feature Group D trunks to a designated destination central office including a stored program control (SPC) switch. The destination central office is a functioning central office connected to other central offices by non-Feature Group trunks. The Feature Group trunks are connected by the switch in the destination central office to a designated line which is connected to a line side modem which is connected via the public data network to a host computer for effecting the credit card authorization.
October 14, 1992
Date of Patent:
May 24, 1994
Bell Atlantic Network Services, Inc.
Robert H. Montgomery, Lawrence A. Delss
Abstract: An output signal of a magnetoelectrical transducer of a capstan DC motor used in a magnetic tape recorder includes a DC offset voltage. The output signal of the transducer is coupled to a non-inverting input of a first operational amplifier. The output signal is also coupled to an inverting input of a second operational amplifier, operating as a comparator. The non-inverting input of the second operational amplifier is coupled to an output terminal of the first operational amplifier that amplifies an AC voltage component of the transducer output signal. By means of two anti-parallel coupled diodes in a negative feedback branch of the first operational amplifier, a DC amplification of unity is obtained as soon as a first peak of the output signal of the transducer is reached.
Abstract: Two volume levels may be produced in a backup alarm merely by reversing polarity of the DC power connections to the circuit of the present invention. The magnitude of output power produced by any device powered by a DC source may be switched between two levels merely by reversing polarity of the power source connected to the device when used with a circuit of the present invention.
Abstract: The circuit includes a differential voltage/current converter (V/I) for connection to the sensor (S), a differential transresistance amplifier (TDA) whose inputs are connected to the outputs of the converter (V/I), and a double-ended/single-ended converter (D/S) connected to the outputs of the amplifier (TDA). The circuit is conveniently formed as an integrated circuit by CMOS P-well technology.
Abstract: A communication unit within a trunked communication system can reduce control channel traffic by maintaining a data base of the communication system services that it can perform. The data base is maintained by the communication unit selecting a service that it desires to perform. Having selected the service, the communication unit verifies that it is one of the services that it can perform and transmits a request to perform that service to a communication resource allocator. The communication resource allocator responds to the request and the communication unit updates its data base based upon the response from the communication resource allocator. The response transmitted by the communication resource allocator may comprise either a grant to the communication unit that allows it to perform the selected service or a denial that the selected service is one that the communication unit is not allowed to perform.
Abstract: In a receiver comprising a receiver filter (12) with a frequency attenuation band and a pilot oscillator (25) for generating a pilot oscillation signal with a pilot frequency in the frequency attenuation band, a coupler (26) couples the pilot oscillation signal and a filtered receiver signal of the receiver filter to form a coupled signal. A low noise amplifier (13) amplifies the coupled signal into an amplified signal which comprises an amplified receiver signal component derived from the filtered receiver signal and an amplified pilot oscillation signal component derived from the pilot oscillation signal. A branching filter (27) branches the amplified signal into the amplified receiver signal component and the amplified pilot oscillation signal. A pilot signal component detector unit (28) detects the amplified pilot oscillation signal component to produce a direct pilot signal.
October 22, 1992
Date of Patent:
May 17, 1994
Japan Radio Co., Ltd., Nippon Telegraph & Telephone Corporation, NTT Mobile Communication Network Inc.
Abstract: In a cordless key telephone system where adjacent service zones having the same control channel are overlapped, forming an unavoidable interference-affected overlapping zone, a main unit initially selects an access unit from each service zone in response to an incoming call from a network and transmits a first alert signal to that unit where it is broadcast to elicit an acknowledgement (ACK) signal from cordless stations. On receiving it, the access unit selects a speech channel, broadcasts a first channel assignment signal on the control channel, and then a first ringing signal on the selected speech channel. The main unit determines whether there is a cordless station falling to respond to the first alert signal. If such a station exists, the main unit selects a first, idle access unit which is located in one of the adjacent service zones. A second alert signal is then broadcast on a control channel from the first access unit.
September 21, 1992
Date of Patent:
April 19, 1994
NEC Corporation, Nippon Telegraph and Telephone Corporation
Abstract: A low profile telephone set which may be used as a table type model or as a wall mount-type model. The telephone set includes a casing and a holder. The casing is formed with a front bottom surface and a back bottom surface forming a predetermined angle there between. The holder is secured to the front bottom surface or back bottom surface in a designated direction depending on the manner of usage.
Abstract: A radio communication device (100) for receiving a signal comprises tracking circuitry (115) for tracking the signal to acquire peak and valley values of the signal, a threshold detector (150) coupled to the tracking circuitry (115) for determining a center threshold of the signal, and an edge detector (180) coupled to the threshold detector (150) and the tracking circuitry (115) for determining a number of center transitions of the signal in a predetermined time period. The radio communication device (100) further comprises a rate controller (185) coupled to the edge detector (180) and the tracking circuitry (115) for receiving the number of center transitions and for adjusting an acquisition rate with which the peak and valley values are acquired in accordance with the number of center transitions.
Abstract: A wireless telephone network includes a distribution network having fixed stations and wireless digital telephones linked by radio to the fixed stations, an integrated services digital public switching telephone network to which each fixed station is connected by a user to user signaling channel, service control points connected to the public switching telephone network and each having a wireless telephone service subscriber database and a call processing device, and a service management system having a reference database. The network is maintained on a centralized basis by transmitting a maintenance message from a fixed station to a service control point over the user to user signaling channel in response to the fixed station detecting a fault, generating a maintenance ticket at the service control point, transmitting the maintenance ticket to the service control point, and storing the maintenance ticket in the database.
Abstract: A digital cordless telephone apparatus comprising a microprocessor based battery powered portable handset unit and a microprocessor based stationary base unit which each transmit and receive digital voice data and digital command data to and from one another over multiple RF channel frequencies in the 902-928 MHz band, is disclosed. The user's voice is digitized, scrambled and modulated for transmission and upon reception, the modulated digital voice data signal is demodulated, descrambled and decoded. A command data - voice data interface inserts command data packets into the stream of digital voice data prior to transmission and locates and captures command data packets from the incoming stream of received digital data. A silence sequence replaces the captured command data packet such that no audible sound is heard by the user.
Abstract: A dipole loudspeaker includes a rigid support containing an opening and a generally planar multi-layered flexible diaphragm mounted on the support and extending across the opening. The diaphragm is formed of a plurality of layers of thin flexible membrane material, each of the layers having a different height and containing a thin electrical conductor arranged in a predetermined pattern on one surface thereof. The conductor patterns on each of the membranes have different masses, whereby the membrane defines along its height areas of various thickness and varying mass whereby the membrane is suitable for more accurately reproducing or generating high and low frequencies when the electrical conductors are connected with a source of sound signal currents. A plurality of magnets are mounted in spaced relation opposite at least one surface of the membrane and the conductor patterns for vibrating the membrane to reproduce the sound in response to the sound signal currents through the conductor.
Abstract: An information communication apparatus includes acoustic and non-acoustic couplers, a switch for selectively connecting an information sending source of the apparatus to the acoustic or non-acoustic couplers, a setting unit for selectively setting items of a communication characteristic of each of the acoustic and non-acoustic couplers, a memorizing circuit for memorizing communication characteristics each having items the values of which are preset by the setting unit, a connection detector for detecting the connection of the acoustic coupler to a communication line, and an information sending controller. The controller connects the sending source to the acoustic or non-acoustic coupler by the switch in response to the acoustic coupler connection or not connection and controls the information sending according to the acoustic coupler or non-acoustic coupler communication characteristic from the memorizing circuit.
Abstract: An improved automatic microphone actuation control system. The system exhibits a high degree of resistance to inappropriate secondary microphone actuation by reverberant sound, even when two or more microphones in a system are operated at significantly different electroacoustic gains. The system further exhibits improved actuation sensitivity to local conference room speech occurring simultaneously with teleconference loudspeaker sound which is strongly coupled acoustically to the microphones. A Reverb Inhibit Bus, which is the maximum of a reduced level speaker inhibit signal and substantially attenuated versions of the DC microphone signal level representations, drives the microphone channels' noise adapting threshold circuitry. Such circuitry is driven in a manner to inhibit microphone actuation for teleconference loudspeaker sound reverberation and reverberation of local conference room speech which has already actuated a microphone.
Abstract: A portable telephone system includes a first telephone network including a terminal station, a first telephone set connected to the first telephone network via the terminal station, a second telephone network including a communication center which is connected to the first telephone network at a connection point, and at least one second telephone set registered in the communication center and connected to the first telephone network via the terminal station. The second telephone set is a portable telephone set having a base station part and a portable station.
Abstract: A digital FM base station radio having a dedicated digital signal processing (DSP) board operates on audio signals from RF links and land lines. The DSP board detects, filters and generates tones and communicates information regarding these tones to a controller microprocessor on the central control board for the radio.
December 3, 1990
Date of Patent:
March 15, 1994
Ericsson GE Mobile Communications Inc.
Rodney L. Nickel, Daniel I. Schwed, Claude L. Vignali