Abstract: A universal wireless radiotelephone communication apparatus is operative in both a first radiotelephone communication system including a first base station having a wide area of coverage, transmitting radiotelephone signals at a first band of frequencies and in a second radiotelephone communication system including a second base station having a localized area of coverage, transmitting radiotelephone signals at a second band of frequencies higher than said first band of frequencies. The second band of frequencies is optimally selected with an offset of less than twice a frequency contained within said first band.

Abstract: In a battery handle two bands of webbed material are each arranged and threaded to independently engage a plurality of slots at opposing ends of a support housing in which a battery is enclosed. Each end includes six slots arranged in pairs of slots. The longitudinal/major axis of the two uppermost slots are at an angle to the horizontal and the major axis of the remaining four slob are substantially horizontal. In another aspect, the band of webbed material is threaded through two or more slots and the ends are joined together. Another technique loops the ends and expands the loop with a mechanical insert to lock it to the support housing.Many variations of the invention will be readily apparent to those skilled in the art which do not depart form the spirit and scope of the invention.

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 microcell unit, in a cellular telephone system using digital signal processing BSs, is digitally connected to a macrocell, via a metallic link, such as a twisted pair. The microcell includes a plurality of radio channel units (RCU), to provide voice connectivity to mobile subscribers (MS), which are under control of a radio control complex (RCC) located in the macrocell. Several time slots of the macrocell TDM bus, through which the RCC exerts control of the RCUs, are remoted to the microcell thereby enabling control of the RCUs at the microcell location by the RCC of the macrocell. This remoting action is achieved, via a remote time division multiplex (TDM) circuit pack which enables the RCC to communicate with the RCUs as if they were located within the macrocell.

Abstract: A boost converter includes a snubber with finite but limited losses to minimize active power switching losses and minimize turn-off losses of the boost diode without generating any additional circulating energy losses. An inductor is connected so as to slow turn off of the boost diode and minimize reverse recovery losses. This inductor additionally minimizes the turn-on switching losses of the active power switch of the converter by providing for zero-current turn-on. A series connection of a finite resistor and a second diode is connected in shunt with the inductor/boost diode connection to prevent excessive voltage ringing across the active power switch by clamping its voltage during turn-off. A third diode is connected to the junction of the inductor and boost diode to prevent the voltage across the boost diode from ringing during the on interval of the active power switch.

Abstract: A DC-DC converter, having multiple outputs, efficiently utilizes its power transformer to provide continuous power output to the outputs except during transitions of the power switches. Energy flow is continuous to one or more outputs during conduction of the power switch and then is transferred to the remaining outputs during its non-conduction. A feedback control, connected to sense only one of the outputs operate the power switch at a controlled duty cycle. Regulation of both outputs is enabled by equalizing transformer volt seconds of the non-conduction and conduction intervals of the power switch and by a clamping circuit which sustains the volt seconds in the power transformer during the non-conduction interval. In a particular embodiment, a converter circuit comprises a transformer having a primary winding and a secondary winding.

Abstract: A capacitor mounting assembly uses a mounting assembly for mounting and aligning a plurality of DC can capacitors on a bulk power system assembly. The mounting assembly includes a metallic base member with a channel cross section having mounting flanges at the longitudinal edges with holes to allow fasteners to pass through and secure the base member to a power system assembly. A top metallic cover plate and a plastic layer cover the top surface of the base member to form a sandwich construction with the plastic layer between the two metallic surfaces. The plastic layer is a polypropylene sheet in the illustrative embodiment. The three layers have holes punched through the sandwich to accept the insertion of the can capacitors.

Abstract: An apparatus and method synchronizes a communication frame of a newly added base station, in a Time Division Multiple Access (TDMA) communication network, to communication frames in the existing communication network of base stations by operating the newly added base station to receive down link signals of a neighboring active base station and synchronize its receive slot in the communication frame with a corresponding forward time slot of the communication frame of that base station. The receive time slot of the newly added base station is shifted by an offset reference time to establish it own forward time slot. The offset reference time is determined by the time interval required for the base station to change from a forward to a reverse channel.

Abstract: A tool for designing the conductors into a PWB includes an audit arrangement for auditing or analyzing crosstalk between electrical conductors to be entered into the PWB. This crosstalk audit may be performed as soon as the initial design is created and before actual manufacture of the PWB. It is operative to identify crosstalk problem areas and to identify impedance mismatches. In particular the audit process defines conduction paths into conduction nets conduction nets are selected one at a time for evaluation and simulated as having an idle current condition. Nearby conduction nets are simulated as being driven in an active condition. The response of the idle network is used to derive a plurality of crosstalk parameters which are used to determine the crosstalk effect on the net under test.

Abstract: A switched mode power converter includes a periodically switched power switch which is switched under the control of a multiple loop feedback controlling the power switch in order to supply a regulated output. The output voltage and power switch current are sensed. An error voltage is generated which is representative of the deviation of the output voltage from a regulated value. A voltage derived from the power switch current is limited in its low frequency response and is then combined with the error voltage. The low frequency response of the current loop gain is used to maintain an advantageously low output impedance for the power supply. This shaped loop gain response advantageously allows accurate adjustment of the current loop gain and reduces the system to a lower order while maintaining adequate loop stability.

Abstract: An isolated MOSFET gate drive includes circuitry to provide a negative gate bias during the off time of the MOSFET to enhance its immunity to inadvertent turn-on. The bias is generated by a self contained two terminal passive network which may be "floated" at any potential with respect to ground. This bias is automatically generated through the action of the network to the gate drive waveform, eliminating the need for an external bias supply to provide this voltage. The bias supply is located locally, thus eliminating the need for long interconnects which may interfere with circuit operation. The bias network in one implementation is a combination of a capacitor and non-linear semiconductor device with a fixed voltage breakdown characteristic. This two-component implementation maintains the capability of producing systems with high packaging densities.

Abstract: Magnetic components are fabricated as monolithic structures using multilayer co-fired ceramic tape techniques. Fabrication of these magnetic components involves constructing multiple layers of a magnetic material and an insulating non-magnetic material to form a monolithic structure with well defined magnetic and insulating non-magnetic regions. Windings are formed using screen printed conductors connected through the multilayer structure by conducting vias.

Abstract: Transitions of a mobile radiotelephone between operating on A band service and B band service are controlled to enable the mobile radiotelephone to utilize the bands of a single service provider over a wide area of cellular service areas in which service is provided on either A or B bands by that single service provider. Each mobile radiotelephone served by a single service provider has an extended home system identification entered into its number assignment module (NAM). When the mobile radiotelephone is operating in a roam mode it scans both the A and B bands searching for the extended home system identification. If the system is successful in locking onto one of the extended home system identification channels the mobile radiotelephone uses that setup channel to establish and receive calls from its original service provider within the present service area. If the lockup can not be made the mobile radiotelephone uses the system I.D. and the A or B band as normally set in the NAM.

Abstract: A switching boost type voltage regulator includes a resonant snubber network connected in parallel with its FET power switch. The snubber includes a FET auxiliary switch that is connected and turned on in order to reduce the voltage across the FET power switch to a zero level at its turn-on transition. A driver circuit, driven by a voltage regulating pulse width modulation (PWM) pulse, initially turns on the FET auxiliary switch to reduce a voltage across the FET power switch and then turns on the FET power switch when the voltage across drops below a threshold level. The FET auxiliary switch is turned off when the FET power switch is turned on. A latch circuit insures the complimentary states of these two switches. The snubber circuit is disabled a near to zero voltage regardless of line and load levels and hence the power dissipation in the snubber is significantly reduced.

Abstract: A dual frequency cellular radiotelephone system, having different service providers, serving mobile subscribers at first and second distinct frequency ranges, uses frequency conversion techniques, to serve both frequency ranges with a minimum of equipment duplication. A first service group is serviced by a first system including a mobile switching center (MSC), a first transmission unit, a first base station controller (BSC), a first base transceiver, a first linear amplifier and first antenna. The entire train of components is designed to support air interface transmissions at the first frequency band at which the first group is served. A signal frequency converter, connected to a transceiver of the first frequency band, converts downlink signals from the first frequency range to the second frequency range and uplink signals from the second frequency range to the first frequency range.

Abstract: In a switch mode power supply the switch current of the power switch is connected to a low pass filter network during the time interval when current is flowing through the power switch. The filter network is disconnected from the power switch when switch current is not flowing. This technique takes advantage of the fact that the average current through the power switch during its conduction interval is either equal to the output current of the power supply, or is proportional with the ratio between the average switch current and the output current being the fixed isolation transformer turns ratio.

Abstract: An estimating circuit for application in estimating or deriving the value V.sub.rms.sup.2 or V.sub.peak.sup.2, of a line voltage V.sub.AC provides fast response time and a substantially ripple free value for these signals by the utilization of a controlled harmonic oscillator whose output precisely tracks the input voltage waveform. Two out of phase (by .pi./2) sine wave signals are derived from the input sine wave and these two out of phase signals are squared and summed to derive or estimate the desired square of the sine waveform signal at a fast response time while substantially excluding ripple of the estimated out of phase sine waves. An estimating circuit, described herein, comprises two integrator circuits series connected into a substantially closed loop. The output of the second integrator circuit is fed back to the input of the first integrator circuit. The output of each individual integrator circuit is a voltage sine wave separated in phase from the output of the other integrator by .pi.

Abstract: A mobile telecommunications system for a large area telecommunications system, including a plurality of different networks, has a directory/network structure for minimizing data storage and transmission and switching capacity requirements for locating roaming mobile terminals. A directory/network structure is provided with a plurality of directory/switching nodes arranged such that only one logical information and transmission path exists between any two nodes.

Abstract: A new communication system merges a voice communication with an image communication into a single transmission channel to provide a virtual voice/video communication service over a limited channel bandwidth. A voice communication path is established between two subscriber communication stations and a desired still picture image is transmitted via the voice channel at the start of the transmission. Portions of the still image expected to be visually active during the communication, such as facial movements (e.g. the lips of the speaker), are replaced at the receiver by an idealized representative image. The voice portion of the transmission is digitally encoded and transmitted from the transmitting station to the receiving station. Synchronous activation of the idealized image (e.g. the lips) are animated by code book coefficients of the digitized speech message.