Abstract: A method for operating a power controller in a wireless communication device is provided that includes generating a power controller output signal using an open loop polar modulation scheme. The power controller output signal is operable to control the power delivered to a high-band power amplifier and a low-band power amplifier. A band state is determined for the wireless communication device. The power controller output signal is provided to the high-band power amplifier when the band state is a high-band state and to the low-band power amplifier when the band state is a low-band state.

Abstract: The design and use of a simplified, highly efficient, waveguide-based wireless distribution system are provided. A low-loss waveguide is used to transport wireless signals from a signal source or sources to one or more receiver locations. One or more adjustable signal coupling devices partially insert into the waveguide at predetermined locations along the length of the system to provide variable, controlled extraction of one or more wireless signals. Low-loss impedance matching circuitry is provided between the waveguide coupling devices and output connectors to maintain high system efficiency. The system offers the capability of supplying signals of high strength and high quality to a large number of receivers in a wide wireless coverage area via a plurality of signal radiators. Some embodiments of the system are readily adaptable for wireless distribution service in HVAC plenum spaces. A system that combines the functions of fire extinguishing and waveguide wireless distribution is also disclosed.

Abstract: The communication system comprises amplification units coupled to the radiating transmission line at periodic locations for amplifying communication signals radiating and traveling upstream and downstream on the transmission line. During normal operation, mobile communication units near the radiating transmission line can communicate with other mobile communication units near the transmission line as well as with a base station by transmitting communication signals at a first and second frequency. The amplification units also comprise degradation detection units which detect when the communication system has been degraded between any two amplification units. Upon detection of a degradation, the amplification units commence to amplify, transmit and receive the communication signals across the location of the detected degradation at a first fault frequency and a second fault frequency, rather than the first frequency and second frequency, respectively.

Abstract: The design and use of a simplified, highly efficient, waveguide-based wireless distribution system are provided. A low-loss waveguide is used to transport wireless signals from a signal source or sources to one or more receiver locations. One or more adjustable signal coupling devices partially insert into the waveguide at predetermined locations along the length of the system to provide variable, controlled extraction of one or more wireless signals. Low-loss impedance matching circuitry is provided between the waveguide coupling devices and output connectors to maintain high system efficiency. The system offers the capability of supplying signals of high strength and high quality to a large number of receivers in a wide wireless coverage area via a plurality of signal radiators. Some embodiments of the system are readily adaptable for wireless distribution service in HVAC plenum spaces. A system that combines the functions of fire extinguishing and waveguide wireless distribution is also disclosed.

Abstract: At a first site, a first antenna exchanges first communications with wireless devices, and exchanges the first communications with a first base station. The first base station exchanges the first communications with a service node. At a second site, a second antenna exchanges second communications with other wireless devices, and exchanges the second communications with a first surface wave interface. The first surface wave interface exchanges the second communications with a second surface wave interface at the first site. The second surface wave interface exchanges the second communications with a second base station at the first site. The second base station exchanges the second communications with the service node. The service node processes the first and second communications to provide a communication service to the wireless devices.

Abstract: A porous ceramic substrate is disclosed that is fabricated from biosoluble ceramic fibers. Porosity and permeability of the substrate is provided by intertangled biosoluble fibers, that can be formed into a honeycomb form substrate through an extrusion process. The fibrous structure is formed from mixing biosoluble fibers with additives that include a bonding agent, and a fluid to provide an extrudable mixture. The structure is sintered at a temperature that exceeds the glass formation temperature of the bonding agent, but less than the maximum operational limits of the biosoluble fiber, to form a structure that has sufficient strength and porosity to provide for filtration and/or as a catalytic host.

Abstract: A mobile communication terminal according to the present invention has a leaky transmission line whose radiation direction faces opposite a radiation direction of a part or a whole of the leaky transmission line of a wireless base station, as at least a part of an antenna element, connected to the communication terminal. Here, preferably, when a difference in angle between the radiation directions falls within the range between 180±7.5 degrees, the radiation directions are considered to face opposite each other. With this configuration, even when the leaky transmission line of the wireless base station has a curved line portion, a curved portion or the like, it is possible to ensure satisfactory communications with the wireless base station without a complicated configuration of the system but by a simple process to build the system.

Abstract: A wireless communication device and method for identifying a container, or communication information about a container using a slot in the container as an antenna. The device includes a wireless communication device for transmitting information regarding the container. The container includes an outer wall forming rim and a slot between the rim edge and the outer wall that is circular and continues without boundaries. The wireless communication device is coupled to the slot to provide the slot antenna for communications. An impedance matching network is additionally provided to make the operating frequency of the slot substantially the same as the operating frequency of the wireless communication device. Alternatively, shorting posts may be placed in the slot to define boundaries of the slot to match the operating frequency of the slot to the operating frequency of the antenna. Multiple feed points may be provided between the wireless communication device and the slot.

Abstract: In a method of controlling transmit power for a user call migrating between a first entity and a second entity in a base station of a wireless communication system, power control may be performed, as a call of the user is migrated from the first to the second entity, or vice versa, based on an adjustment ratio value. Parameters for balancing transmit power as the user call is migrated from the first entity to the second entity may be selected so that any difference in transmit power does not adversely affect system performance.

Abstract: The present invention is to provide communication apparatus capable of selecting a transmission scheme suitable for a type of transmission information, its communication method, and programs. A transmitter/receiver portion 2 is capable of communicating under plural transmission schemes of different transmission rates in accordance with combinations of coding rates of a convolutional encoder and modulation schemes. A transmission scheme selection portion 5 prioritizes the transmission schemes in a plurality of different evaluation schemes in response to signal Ds representing the type of transmission information based on measurement results S4 measured at a measurement portion 4 and selects the optimum transmission scheme to be used for communications from the plural transmission schemes according to the prioritized result. The selected transmission scheme is sent to the transmitter/receiver portion 2 for switching the transmitter/receiver portion 2.

Abstract: An inter-base station synchronization system is constructed without using any receiver for detecting a frame period error at a zone boundary between leaky coaxial cables, and without using any exclusive line or dedicated radio waves for use in transmitting the frame period error information from this receiver to base stations. This system has a plurality of base stations provided in certain intervals, leaky coaxial cables laid down between the base stations, and one, or a plurality of, mobile station that measure a time delay difference of received signals from adjacent ones of the base stations while the mobile stations move along zone boundaries between leaky coaxial cables, and that transmit the delay time difference information through the leaky coaxial cables to at least either one of the two adjacent base stations.

Abstract: A method is provided for producing a highly porous substrate. More particularly, the present invention enables fibers, such as organic, inorganic, glass, ceramic, polymer, or metal fibers, to be combined with binders and additives, and extruded, to form a porous substrate. Depending on the selection of the constituents used to form an extrudable mixture, the present invention enables substrate porosities of about 60% to about 90%, and enables process advantages at other porosities, as well. The extrudable mixture may use a wide variety of fibers and additives, and is adaptable to a wide variety of operating environments and applications. Additives can be selected that form inorganic bonds between overlapping fibers in the extruded substrate that provide enhanced strength and performance of the porous substrate in a variety of applications, such as, for example, filtration and as a host for catalytic processes, such as catalytic converters.

Abstract: The present invention provides a wireless communication system includes a plurality of leaky transmission lines and sufficiently increases a wireless area. The present invention relates to a wireless communication system which includes a wireless base station; a plurality of leaky transmission lines that function as antennas of the wireless base station; and a selector for selecting each of the leaky transmission lines and thereby connecting the leaky transmission lines to the wireless base station, wherein only one leaky transmission line is selected and connected at any given time. The selector may select all of the leaky transmission lines cyclically, one at any given time. Alternatively, the selector may select one of the leaky transmission lines according to a control signal from a selection controller.

Abstract: A method and apparatus of transmitting a communication signal between a radio base station and a radiation element. In one embodiment, the method includes receiving an input signal. Then extracting a data signal from the input signal, the data signal includes values representing operating parameters of devices at the radiation element. And producing a status signal for each device that simulates a feedback signal for the device.

Abstract: A method for communicating to a recipient transceiver from a plurality of transceivers located within the broadcast range of the recipient transceiver includes: transmitting a communication at a first power level such that only a first group of transceivers receive the broadcast, the communication including a command causing each of the first group of transceivers not to respond to a subsequent broadcast; and subsequent thereto, transmitting a communication at a second power level greater than the first power level such that a second group of transceivers greater than and including the first group of transceivers receive the broadcast, but such that only a limited number of transceivers of the second group respond to the broadcast, the limited number of transceivers excluding the first group of transceivers. Each of the plurality of transceivers is associated with a respective sensor for acquiring data and transmitting the data to the recipient transceiver.

Abstract: A CATV network is modified with a secondary transmission (CBP) by adding filters to separate modified mobile-communications frequencies. A CATV terminal can be routed to cellular network by way network coupling devices (NCD).

Abstract: A radiation information management device comprises a measuring unit, a comparing unit, and a management information generating unit. The measuring unit measures unwanted radio wave radiation radiated from a balanced transmission line. The comparing unit compares a measured value of unwanted radio wave radiation, which the measuring unit has measured, with a reference value that is predetermined, and then notifies the comparison result to the management information generating unit. The management information generating unit refers the comparison result, generates the management information related to the unwanted radio wave radiation including information showing that the measured value is exceeded the reference value, then notifies to a first communication device and a second communication device. The first communication device and the second communication device take a measure to reduce transmitting power based on the management information regarding the unwanted radio wave radiation.

Abstract: A communications network including first and second stations, the first station comprising a transmitter and the second station comprising a receiver. The network further including a transition control portion which is operable, prior to a change in a transmission rate of a preselected signal from the first station to the second station, to cause transitional signals to be transmitted from the first station to the second station over the course of a transitional period expiring before the change is effected. The power levels of the transitional signals are varied over the course of the period in such a way as to reduce a level of instability in the network. In another embodiment probing signals are transmitted prior to making such a rate change to probe a likely relationship between the transmission rate and transmission power after the change is effected.

Abstract: Methods, systems, and computer program products for selection of visually displayed audio data are provided. In one implementation, a computer-implemented method is provided. Original audio data is displayed in a plurality of visual forms. A first input is received selecting a region within a first visual representation of the original audio data. A second input is received selecting a region within a second visual representation of the original audio data. Audio components from the selected regions are isolated to provide isolated audio data. The isolated audio data corresponds to audio data common to both user selected regions. The isolated audio data is edited and then missed into the original audio data.

Abstract: The present invention jointly controls rate and power in a fashion that enables control of the two variables in one dimension. In some embodiments, this is done by ordering the possible transmit rate (320) and transmit power (340) combinations in a logical sequence that meets specific conditions. The present invention can first minimize the transmit time and then reduce the transmit power. The present invention can maintain the maximum rate possible that enables the receiving station to decode packets with an acceptable probability.

Abstract: A cable has miniaturized, low-cost, highly-integrated wireless network access points embedded in the cable at periodic intervals along the length of the cable. Power conductors that run the length of the cable supply each of the access points with electrical power. Each access point has an antenna for receiving and transmitting radio signals. The antenna of an access point is encapsulated, along with the rest of the access point circuitry, underneath an insulating protective outer sheath of the cable. The cable includes conductors that are usable for a purpose other than deploying a wireless network. When the cable is physically installed (for example, in the wall or ceiling of a building) for the other purpose, the access points are simultaneously physically installed. The access points so installed can then be activated and used as part of a wireless network.

Abstract: Transistor package leads form quarter-wave antenna elements that directly radiate RF energy into free space without the need for a separate antenna. The transistor operates at a fundamental frequency and radiates a harmonic, thereby allowing radiation at frequencies normally considered “beyond cutoff” for a packaged transistor. This technique enables an additional 20 GHz of spectrum for use by surface mount technology. The transistor may be mounted on 1.6 mm thick glass-epoxy circuit board that also forms a quarter-wave reflector at 26 GHz. An optional dielectric lens produces a narrow beam and an optional planar filter rejects spurious fundamental emissions. A 26 GHz ultra-wideband (UWB) pulse-echo radar rangefinder implementation provides a low-cost upgrade to ultrasound.

Abstract: Dual site supervision is provided for a control channel cellular radio for a fire alarm reporting system that uses logic that causes a control channel cellular transceiver to operate in a nonstandard manner and to use a different and second cellular base station or site that the unit would not normally select operating pursuant to a standard cell phone software module. The logic causes the control channel cellular transceiver to monitor and test through more than one cell base station or site, thereby meeting the dual communication path supervision requirement for UL listed communications systems for stand alone fire alarm reporting systems. The available cellular control channels are first scanned, and the signal strength of each cellular control channel is measured.

Abstract: A mobile terminal can include a printed circuit board with a reference voltage conductor, an antenna coupled to the first side of the printed circuit board, and a parasitic resonator coupled to the second side of the printed circuit board. More particularly, the parasitic resonator can be connected to the printed circuit board by first and second couplings, which provide first and second impedances, respectively, between the parasitic resonator and the reference voltage conductor. The impedances can be of different values, and can be provided by discrete impedance components. The resonant frequency of the parasitic resonator can be adjusted by altering the impedances of the first and second couplings.

Abstract: A wireless communications systems employing code-division multiple access information transmission techniques includes a transmission facility having ground-based transmission and reception electronic equipment, a remotely located RF power amplifier, an antenna, and an RF cable connecting the ground-based equipment with the remotely located RF power amplifier. Power level detectors in the ground-based equipment and in the remotely located RF power amplifier measure the signal level at each end of the RF cable. A microcontroller compares these measurements and adjusts a variable attenuator in the transmission signal path and a variable attenuator in the received signal path to compensate for signal level variability due to variations in signal loss.

Abstract: A system is provided for increasing the number of users capable of communicating over a wireless network to permit multiple users to transmit information simultaneously on the same channel or frequency in which a Viterbi decoder-based signal separation system is used to pull apart or uncorrupt the otherwise interfering signals on the channel. In one embodiment, two users are assigned to the same channel, with a joint parameter estimation pre-processor being utilized to provide an estimation of the power, time and frequency offsets and phase of the incoming signals. The joint parameters estimated by the parameter estimation unit are applied to a signal separator which recovers and pulls apart the two signals.

Abstract: A radio frequency communication system utilizing a radiating transmission line for communicating data signals is disclosed. The data signals convey digital data to remotely located data devices, including computers, equipment control systems and digital video cameras. The data signals have a wide bandwidth of about 0.5 MHz to 32 MHz. In this way, the communication system creates a local area network by means of the radiating communication line. The communication system is intended to be used in environments where radio waves do not propagate well, such as in underground environments, and in particular mines. The communication system comprises at least one amplifier connected to the radiating transmission line for periodically amplifying the data signals by demodulating the data signals to recover the data contained therein and then modulating the recovered data into a regenerated radio frequency at a power level permitting transmission and radiation of the regenerated radio frequency data signal.

Abstract: A wireless communication device and method for identifying a container, or communication information about a container using a slot in the container as an antenna. The device includes a wireless communication device for transmitting information regarding the container. The container includes an outer wall forming rim and a slot between the rim edge and the outer wall that is circular and continues without boundaries. The wireless communication device is coupled to the slot to provide the slot antenna for communications. An impedance matching network is additionally provided to make the operating frequency of the slot substantially the same as the operating frequency of the wireless communication device. Alternatively, shorting posts may be placed in the slot to define boundaries of the slot to match the operating frequency of the slot to the operating frequency of the antenna. Multiple feed points may be provided between the wireless communication device and the slot.

Abstract: An Electromagnetic Field Communications System for Wireless Networks for producing an electromagnetic field within a structure is disclosed. The electromagnetic field is produced by using common conductive elements already present within virtually all pre-existing residential commercial, industrial buildings. These conductors, which may include electrical ground shields, wiring, pipes, sprinkler conduits or structural members, are excited with a signal, and become the cavity which contains the electromagnetic field. In preferred embodiments of the invention, signals are generated using the High Frequency, Very High Frequency and lower UHF bands (3 to 30, 30 to 300 and up to 400 MHz). The invention may be used to create a local area network inside the field and within the structure. Devices that include receivers tuned to the electromagnetic field may then be connected and networked.

Abstract: There is disclosed a signal monitoring apparatus for use in a wireless network base station containing a modular main unit for processing baseband signals and a modular radio unit separate from the main unit for transmitting and receiving radio frequency (RF) signals. The signal monitoring apparatus is disposed in the radio unit and monitors an RF output signal transmitted by a transceiver in the radio unit. The signal monitoring apparatus comprises an RF mixer that mixes the RF output signal and receiver local oscillator (LO) signal used by the receiver portion of the transceiver to demodulate received RF signals. The RF mixer generates an intermediate frequency (IF) signal capable of being transmitted through a communication line at relatively low signal loss to a signal measuring device located in the main unit or elsewhere.

Abstract: A device for generating a radio frequency electrical signals, delivering at least two separate signals having different frequencies, in the form of signals delivered by different primary sources and amplified with a predetermined gain. The device comprises a combining circuit (3), combining the signals delivered by the primary sources (2), a single channel power amplifier (4) and a multi-channel selection and routing unit (5) with a parallel structure. Each channel delivers at the output an amplified signal (S) at a frequency (F) characteristic of one of the primary sources (2) and comprises a filter circuit (6) adjusted to be passing for one of the different characteristic frequencies (F) of the different primary sources (2), an impedance adaptation circuit (7) and a rejection circuit (8) for frequencies other than the passing frequency of the filter circuit (6) of the channel in question.

Abstract: Disclosed is a method for determining a forward data rate and a forward transmission power level in a mobile communication system. An access terminal measures a C/I of a forward pilot channel, determines a forward data rate by matching the measured C/I with a reference C/I, creates a difference between the measured C/I and the reference C/I as margin information, and transmits the determined forward data rate and margin information over a reverse transmission channel. Upon receipt of the forward data rate and margin information, an access network decreases a transmission power level by power corresponding to the margin information and performs forward transmission at the forward data rate at the decreased transmission power level.

Abstract: A distributed transceiver for wireless communication system providing access to a public data communication network is disclosed. A plurality of RF access points are positioned in a premises to provide service coverage for mobile wireless according to a local wireless communication protocol. Each of the RF access points is coupled to a central controller by a cable to permit transmission of a low voltage DC power signal to the RF access point and transmission of uplink and downlink signals between the central controller and the RF access point.

Abstract: A PDC/PHS phone has both PDC communication function and PHS communication function. The PDC/PHS phone switches its communication mode from a PDC communication to a PHS communication which is less power consuming than the PDC communication, when its built-in battery runs down to a reference level in the course of communication with another phone. The PDC/PHS phone switches its communication mode back to the PDC communication again, when the battery is recharged enough.

Abstract: A arrangement is described for transmitting, radiating and receiving high-frequency signals. The arrangement is comprised of a system connected to a transmitting and receiving device (3) which includes at least one high-frequency element (1) capable of guiding electromagnetic waves and a first signal cable (5) extending parallel thereto. To improve the service reliability of the arrangement, a second signal cable (6) which is also connected to the transmitting and receiving device (3), is arranged parallel to the high-frequency element (1) and maintains a significant spatial separation to the first signal cable (5).

Abstract: A novel base station for cellular wireless communications based on a modular structure is provided. The modular cellular wireless communication base station includes a plurality of active radiator modules (ARM's) located at a desired antenna location, a beam forming network controlling relative amplitudes and phases of each of the modules and an RF front end. Each module (100) includes at least one antenna (ant) for transmitting and receiving, a transmitter having a power amplifier, and receiver.

Abstract: A method and apparatus for providing an antenna condition signal and a feeder cable condition signal in a base station having an antenna coupled to a cabinet by an antenna feeder cable. Two directional couplers are configured to detect forward and reflected signals to and from the antenna. Power detectors are coupled to the RF couplers, and are configured to provide forward and reflected power signals. A first differential amplifier provides a detector tuning signal proportional to the difference between the forward and reflected power signals. A second differential amplifier provides a detector tuning signal proportional to the difference between the forward and a reference voltage. Each differential amplifier tunes a voltage controlled oscillator (VCO). The output of the VCOs is coupled to the feeder cable. A phase locked loop at the cabinet is coupled to the feeder cable and provides a recovery tuning signal which tracks the tuning signals to the differential amplifiers.

Abstract: A data communication system is configured to communicatively link a host device and a client device with a point-to-point data communication link, where the point-to-point data communication link is configured with multipoint network data communication components designed for data communication over a distributed network. A data communication interface at the host device is communicatively linked with a data communication interface driver via the point-to-point data communication link between the host device and the client device. The data communication interface driver communicates with a virtual driver component for the client device via a virtual network at the client device.

Abstract: A method of controlling the traffic load in a telecommunications system, in which the communication between terminals and the network takes place through an air interface, includes determining a dummy traffic load that is to be generated, and generating the dummy traffic load in the network. An apparatus for controlling the traffic load in a telecommunications network is also disclosed, including a device for determining the dummy traffic load to be generated, and a device for generating the dummy traffic load. The traffic load to be generated may be determined on the basis of the current traffic load, for example, to keep the total traffic load at a constant level or to add dummy traffic load to the ordinary traffic load in dependence on the current ordinary traffic load.

Abstract: A arrangement is described for transmitting, radiating and receiving high-frequency signals. The arrangement is comprised of a system connected to a transmitting and receiving device (3) which includes at least one high-frequency element (1) capable of guiding electromagnetic waves and a first signal cable (5) extending parallel thereto. To improve the service reliability of the arrangement, a second signal cable (6) which is also connected to the transmitting and receiving device (3), is arranged parallel to the high-frequency element (1) and maintains a significant spatial separation to the first signal cable (5).

Abstract: Disclosed is a mobile communication system and method. A base station (BS) transmits and receives signals using predetermined serving frequency signals. A donor module, coupled to the BS, converts output signals of the BS into intermediate frequency (IF) signals and performs a power control operation on the signals and outputs resulting signals to a path. Each of a plurality of remote modules receives output signals of the donor module through the path and converts the signals into serving frequency signals, then outputs the converted signals to a mobile station (MS) within a blanket area. The remote module converts signals received from the MS into IF signals and outputs the signals to the donor module through the path. The donor module converts the IF signals provided from the remote module through the path into serving frequency signals and transmits the signals to the BS. Therefore, the present invention easily removes blanket areas in a building at a low cost.

Abstract: A system is provided for increasing the number of users capable of communicating over a wireless network to permit multiple users to transmit information simultaneously on the same channel or frequency in which a Viterbi decoder-based signal separation system is used to pull apart or uncorrupt the otherwise interfering signals on the channel. In one embodiment, two users are assigned to the same channel, with a joint parameter estimation pre-processor being utilized to provide an estimation of the power, time and frequency offsets and phase of the incoming signals. The joint parameters estimated by the parameter estimation unit are applied to a signal separator which recovers and pulls apart the two signals.

Abstract: Uniform and concentrated radio broadcast signals are obtained employing an antenna structure which uses separate antenna conductors on opposite sides of a radio reception area. The antenna conductors perform similarly to the plates of a capacitor. Highly efficient antenna performance results. In a preferred embodiment wherein the antennas are used for radio testing inside a vehicle assembly plant, the track or carrier structure of the vehicle assembly line provides one of the antenna conductors.

Abstract: An antenna system for a multi-channel, two-way UHF underground communication includes a base radio station; a non-radiating coaxial cable attached to the transmit/receive connector on said base radio station; radiators affixed to said non-radiating coaxial cable at predetermined intervals along the length thereof, wherein said radiator is insulated from the center conductor of said coaxial cable; and bi-directional amplifiers spaced at predetermined intervals along the length of said coaxial cable.

Abstract: Apparatus and a method are disclosed for a wireless telephony system to eliminate blind areas where signal coverage is weak or non-existent by providing remote transceivers that are physically located in the blind areas. A central transceiver located with a base telephone station and tower mounted antenna receives wireless telephony signals being transmitted by the antenna to a wireless telephone and forwards it over either an dedicated or existing broadband distribution network, such as a cable television distribution network, to the remote transceiver which transmits the same telephony signals in the blind area to a wireless telephone operating in the blind area. Telephony signals originating from a wireless telephone operating in the blind area are received by the remote transceiver and forwarded over either the dedicated or existing broadband distribution network to the central transceiver which inputs the telephony signals to the base telephone station.

Abstract: A distributed strip-type radiating cable comprised of a plurality of generally flat conductive strips disposed in substantially parallel relationship to one or more generally flat dielectric materials, adapted to radiate RF energy for communications applications. The radiating cable is designed to be efficiently and inexpensively manufactured and installed from lightweight, small size materials, and is designed to be easily attached and secured to a variety of surfaces.

Abstract: An encapsulated tubular conductor having at least two antenna elements disposed on the capsule thereof for maintaining therebetween wireless information transmission in a transmitting-receiving direction, and a transmitting-receiving device located outside the capsule and assigned to one of the antenna elements includes another transmitting/receiving device also disposed outside the capsule and assigned to the other of the antenna elements, the antenna elements being directed towards an interior space of the capsule, the interior space serving as a transfer path via which information is transferable between the transmitting-receiving devices.

Abstract: Radio telephone apparatus for use in an underground railway system comprises two base stations 3, 4 respectively located at successive railway stations 1, 2. The base station 3 feeds a radiating cable 7 extending in the tunnel bore towards the base station 4 which feeds a radiating cable 12 extending in the tunnel bore towards the base station 3. When a train travels from the station 1 to the station 2, the mobile radio on the train effects call handover, ie transference of communication with cable 7 to communication with cable 12. To ensure no interruption in a call during handover, an attenuator 16 is incorporated in the cable 7 adjacent its end, such that the mobile radio effects call handover to the cable 12 before losing communication with the cable 7, even at the maximum possible speed of the train.

Abstract: A radio communications system is intended for use by trains in a tunnel. This system includes an antenna subsystem which incorporates a radiating coaxial cable disposed along the length of the tunnel and extending beyond the portals thereof, including surface coverage for transition. Plural bi-directional, in-line amplifiers are inserted along the length of the radiating coaxial cable at predetermined intervals for amplifying the RF signals carried by the radiating coaxial cable. A monitoring repeater and a control repeater are provided along with an interface for joining the two repeaters to the radiating coaxial cable. A monitoring subsystem includes an end-of-train device and a head-of-train device.

Abstract: The coverage area of the base station of a cellular radio system is expanded in a very simple and easily implementable way by utilizing the cabling present in a community antenna system, so that the community antenna system and a repeater connected thereto are used for transmitting telecommunication signals between the base station and a subscriber unit served by the system. The base station can also transmit on the control channel to the repeater information as to which radio channel and which power level the repeater should at each time repeat the signals it receives, to ensure that the signals intended for a specific subscriber unit are repeated on a traffic channel and power level suitable for the purpose. The base station can reduce the power level used by the repeater to such a level that a plurality of repeaters utilizing the same traffic channel can be placed close to one another without disturbing one another.