Abstract: An apparatus for monitoring a cellular communications system; comprising a plurality of voltage standing-wave ratio (VSWR) measurement means located at respective connections to antennas of said communications system and at respective discontinuities in radio transmission lines to said distributed antennas; wherein each said VSWR measurement means is individually identifiable, has a respective threshold, and is arranged to compare its measured VSWR value to its respective threshold and identifiably indicate an error status if its measured VSWR value exceeds its threshold. Also described is a corresponding method of monitoring a cellular communications system. Also described is a VSWR measurement apparatus, and an antenna arrangement comprising an antenna and such a VSWR measurement apparatus.

Abstract: An externally-powerable sensor is described for detecting ultrasonic energy and for providing an accurate indication of the level of such energy to an external monitoring device over a wide dynamic range. A first electrical signal proportional to the detected ultrasonic energy is chopped by the output of a free-running multivibrator to generate a signal having a frequency differing from the frequency of the first signal by an amount within the audio frequency range. Such difference signal is selectively amplified to concentrate the spectral energy of the difference component in a lower portion of the audio range. A low pass filter extracts, from the so-concentrated difference signal, a modified audio signal whose frequency content is at the lower end, illustratively 0-6 KHz, of the spectrum of the concentrated difference signal. The output of the low pass filter is processed to generate a DC output current that is proportional to the detected ultrasonic energy level.

Abstract: A time division multiple access (TDMA) communications system (20) includes a first TDMA platform (22) for transmitting a call (32) over a circuit switched communication link (36) to a second TDMA platform (24). The call (32) exhibits a first signal type (84) and second signal type (86). A controller (42) establishes a capacity allocation (200) responsive to the first signal type (84) for the communication link (36). When the call (32) exhibits the first signal type (84), the first TDMA platform (22) transmits first packets (111) of the call (32) in a first packet format (113) using the capacity allocation (200), and when the call (32) exhibits the second signal type (86), the first TDMA platform (22) transmits second packets (140) of the call (32) in a second packet format (139) using the capacity allocation (200).

Abstract: A point-to-multipoint (PTM) radio communication system (20`) includes a cellular radio infrastructure (22) having base stations (32) implemented in satellites (34) placed in low earth orbits (38). PTM subscriber radios (24) share common cellular radio infrastructure (22) multipoint channels (52) to engage in a common PTM communication session while the cellular radio infrastructure (22) also conveys point-to-point communications. The shared multipoint channels (52) are operated in according with different protocols to deliver system information to PTM subscriber radios (24), to provide access to PTM subscriber radios (24), to provide synchronization, to originate a PTM monolog and to be one of many targets of a PTM monolog.

Abstract: An apparatus for detecting ultrasonic energy generated by a mechanical device and for applying lubricant to the device is presented. The apparatus includes a lubrication tool, such as a grease gun, which has a lubrication delivery element for delivering lubrication to the mechanical device. An ultrasonic transducer is contained in a housing which is removably attached to the outside of the lubrication delivery element. The housing is configured to acoustically isolate the transducer from the lubrication tool. An acoustic waveguide depending from the housing is provided to carry ultrasonic energy from the device to the transducer when the lubrication tool is applied to the device. An electrical circuit, which may be attached to the lubrication device, produces an output signal which indicates the magnitude of detected ultrasonic energy.

Abstract: Interoperability between terrestrial cellular systems and satellite based cellular systems allows handoffs between different cellular systems. A call in progress by a subscriber unit (101) over a terrestrial based cellular system (100) which includes a mobile switching center (MSC) (105a) and a plurality of base stations (103a-d) is handed off to a satellite based cellular system (1000) comprising a satellite network (100a, 1001b), a regional gateway (1007) and an interface gateway (1005). A call in progress by subscriber unit (101) over satellite based cellular system (1000) is also handed off to terrestrial based cellular system (100). A dual mode subscriber unit (400) provides switching functionality (409) to switch between transmit modes.

Abstract: A ball retrieval and storage device for retrieving balls of at least two different sizes comprising a wheeled container with rotatably attached handles attached thereto. The container is rollingly supported by two wheels on an axle, and includes a removable rack which when in place covers the container to ensure the contents remain within the container. When the removable rack is placed beneath the container, the entire device is elevated to prevent needless bending and stooping by the user. The device further comprises a retrieval opening which includes a fixed member and a movable member to provide a variable spacing between them depending on the size ball to be retrieved. The device is placed near a ball to be retrieved, tilted backward onto its wheels, rolled forward such that the ball is beneath the opening, then returned to its upright position in order to capture a ball.

Abstract: A packet data communication system (10) where multiple users (87) can access the same channel (22) to maximize an efficiency of the communication system (10). Each channel (22) is divided into time slots. Each time slot is allocated to a user based on the user's request (303) for time slots and the availability of time slots. If time slots are available, then the system (10) will inform the user (87) and allocate the time slot to the user (87, 305). If there are no available time slots, then the system (10) will inform the user (87) that no time slots are available and access to the system's channel is denied. The user (87) will continue to request access (303) to the system (10) as long as the user has data packets to send.

Abstract: An on-board aircraft telecommunication exchange (32) provides communication and authentication services for M subscriber identity modules (SIMs) using N transceivers (36), where M can be greater than N. Associations between SIMs (56) and transceivers (36) are established when needed. Accordingly, a pool of transceivers 36 is provided to serve the collective needs of many subscribers. A SIM based authentication process is performed (100) using a subscriber's original SIM (56). That authentication can be extended to a temporary SIM (106) that is substituted for the original SIM throughout the remainder of a flight. Alternatively, the original SIMs (56) may be locked in place and relinquished when a subscriber provides an appropriate PIN.

Abstract: An on-board aircraft telecommunication exchange (32) provides communication and authentication services for M subscriber identity modules (SIMs) using N transceivers (36), where M can be greater than N. Associations between SIMs (56) and transceivers (36) are established when needed. Accordingly, a pool of transceivers 36 is provided to serve the collective needs of many subscribers. A SIM-based authentication process is performed (100) using a subscriber's original SIM (56). That authentication can be extended to a temporary SIM (106) that is substituted for the original SIM throughout the remainder of a flight. Alternatively, the original SIMs (56) may be locked in place and relinquished when a subscriber provides an appropriate PIN.

Abstract: Private Global Networks (PGNs) between communication terminals (110, 114, 116, 118) are established within a satellite communication system (100). Each PGN provides to its users a network of dedicated communication paths which have durations that exceed the duration of a particular call. A dedicated communication path is established by determining (416, 424) hand-off schedules for satellite-to-terminal links for both a source and destination terminal, and also by determining (428) satellite cross-link schedules necessary to maintain the dedicated path for a duration which exceeds the duration of a particular call.

Abstract: A method and apparatus for a communication system (100) to register groups of co-located users in a mobile vehicle (110) involves collecting (200) registration information for multiple users by a Vehicle Communications Control Unit (500) (VCCU) on board the mobile vehicle (110), creating (202) at least one group registration request message by the VCCU (500), and sending the at least one group registration request message to an Earth Terminal (102) (ET) of the communication system (100). After the communication system (100) registers each user whose registration information is contained within the at least one group registration request message, the ET (102) sends (312) at least one group registration response message to the VCCU (500), where the message includes information describing whether each registration attempt was successful. The VCCU (500) can then inform (210) each user as to the status of the registration attempt.

Abstract: In satellite based communication systems (30), real time monitoring of communication links (23-25) and the subsequent adaptations to overcome problems with certain links (23,25) provides the communication system (30) with the ability to adapt to changing conditions. A satellite-based communication system (30) can be adapted to provide an improved method for establishing communication links (23,25) between ground stations (14) and space-based satellite switches (11). Common earth-based termination nodes are replaced by intelligent switches (14). Alternate links are established using links (20,21) between intelligent space-based switches (11), links (24) between intelligent earth-based switches (14), and links (23,25) between intelligent space-based switches (11) and intelligent earth-based switches (14). The controller (54) in the intelligent earth-based switch (14) allows the system to automatically adapt to failure, overload, and other conditions.

Abstract: A method for a network in a multi-network system to obtain access information for a subscriber unit (104) (SU) involves requesting (1306) access information from an access server (110) which determines (1208) whether a group to which the SU belongs can access the network or another network from the SU location. The access server (110) can also send (1228) information to a network which describes which other networks the SU group can access from the SU location. An access server apparatus (1800) includes a processor (1802) for making access decisions in a multi-network system, a memory device (1804) for storing access information (1100) for various networks, and at least one network interface (1806). A gateway (GW) apparatus (2000) contacts an access server (110) to obtain access information. An SU apparatus (1900) includes a processor (1902) for using information from the access server (110) to access a network.

Abstract: A method for fabricating a resistive load element for a semiconductor device can be used with standard semiconductor processes. A layer of second level poly is deposited and lightly doped P-type. A resist mask is used to dope selected regions of the poly layer N-type. The poly layer is then patterned to define conductors and resistive load elements. The resistive load elements are formed by back-to-back PN diodes formed at the interfaces between the P-type and N-type regions.

Abstract: A method for handing off calls between differing radio telecommunication networks recognizes (302) a desire for an inter-network hand-off. When a Subscriber Unit (120) (SU) identifies (304) a new network, a hand-off with the new network can be requested (320). When the SU (120) does not identify (304) a new network, the old network requests (314) location information relevant to an inter-network hand-off from a Location Inter-Working Server (200) (LIWS). The LIWS (200) provides information about other networks which provide service to the SU location and, when another network provides service to the SU location, a hand-off with the other network can be requested (320).

Abstract: A digital telecommunication network (10) provides an audio processor (56) for each call in each external node (14). The audio processor (56) includes a vocoder and additional functions. At a source external node (14), the audio processor (56) detects DTMF events and encodes the events in a call-related signalling packet (26) which conveys a history of all DTMF activity at the source node over the past several seconds. In addition, the source node detects silence and configures a call-related signalling packet (26) to instruct a destination node (14) how to synthesize comfort noise. Speech is encoded as vocoded voice packets rather than call-related signalling packets. At a destination external node, the node's audio processor (56) distinguishes call-related signalling from vocoded voice. The audio processor (56) synthesizes voice, comfort noise, DTMF signals, and other signals in response to the call-related signalling packets and vocoded voice packets.

Abstract: In a communication system (10) which includes a communication unit (56) (CU), a Mobile-Switch Interface (50) (MSI), and a Mobile services Switching Center (40) (MSC), a method for location registration and call continuation involves the MSI (50) determining (174) whether the CU (56) intends to utilize a system service after the CU (56) completes a location updating process without releasing a channel between the CU (56) and the MSC (40). When the CU (56) does intend to utilize the system service directly after the location updating process, the MSI (50) allows the CU (56) to utilize the system service regardless of whether the MSC (40) indicated that the CU (56) cannot utilize the system service without first releasing the channel.

Abstract: A method for fabricating a resistive load element for a semiconductor device can be used with standard semiconductor processes. A layer of second level poly is deposited and lightly doped P-type. A resist mask is used to dope selected regions of the poly layer N-type. The poly layer is then patterned to define conductors and resistive load elements. The resistive load elements are formed by back-to-back PN diodes formed at the interfaces between the P-type and N-type regions.

Abstract: An ESD protection circuit and structure for implementation within an integrated circuit is disclosed. The protection circuit includes a diode, serving as a triggering device, and a lateral bipolar transistor. The triggering voltage of said diode is selected by an implant underlying a first field oxide structure adjacent a first diffused region to which the external terminal is connected. The lateral bipolar transistor uses the first diffused region to which the external terminal is connected as the collector region, a second diffused region opposite the first field oxide structure from said first diffused region as the emitter, and the substrate, or epitaxial layer, as the base. A second field oxide structure encircles the emitter region and has a distance thereacross which is selected in order to provide sufficient base resistance that, upon junction breakdown of the diode, the base-emitter junction of the lateral transistor is forward biased and the transistor turned on.