1588 results about "Return channel" patented technology

A communication system balances message traffic between return channel groups and within the groups, so that the user does not control the specific transmission frequency used. Uplink frequencies and bandwidths for the return channels are set by the system in a return channel control message in the broadcast signal so as to account for system and return channel group loading, and to account for user message backlogs. An initial transmission from a remote user may be made using an ALOHA-type burst signal that provides a message backlog to the control station, and is made on a frequency determined from a randomly weighted, load-based frequency selection process. The system, and not the individual users determine the frequency and channel allocations. For large backlogs or priority users, periodic bandwidth is provided. A method for balancing loads among and between groups of return channels in the communication system includes requesting return channel bandwidth in an uplink message from a remote user to a control station. The uplink message may include a both a backlog indicator and a bandwidth allocation request provided to a Network Operations Center (NOC) which can be used to set the return channel bandwidth and frequency for the remote uplink. A user message is transmitted on the designated return channel frequency using bandwidth allocated in accordance with the backlog indicator and a bandwidth allocation request so that traffic loads are maintained in balance between established return channel frequency groups, and within each return channel frequency group.

A communications system consisting of a server system that stores software applications, a broadcast system that broadcasts the software applications, and a multiplicity of portable clients that each include a receiver having a tuner that is selectively tunable to receive a selected one of the software applications broadcasted by the broadcast system. The portable clients can be any type of portable data communications device, such as a hand-held, palm-top, or notebook computing device, a PDA, an intelligent cellular phone, or any other personal multimedia appliance or Network Computer (NC). The broadcast system can be any suitable satellite or terrestrial air or cable broadcast system. The software applications can consist of a broad spectrum of different software applications, such as word processing, video games, spreadsheets, address books, calendars, and the like. Each of the portable data communications devices includes a receiver that has a tuner that is selectively tunable to receive a selected one of a plurality of software applications broadcasted by a broadcast system, a user-interface that enables a user to select one of the broadcasted software applications for downloading, a processor for executing the downloaded software applications, and a modem for establishing a two-way communications link with a network control system. The two-way communications link includes a forward channel over which the portable data communication device can transmit client data to the network control system, and a return channel over which the network control system can transmit system data to the portable data communication device. The client data can include requests for unrecoverable software application data and client software download request data.

A method for deicing a rotor blade having a blade root, a blade tip, and a leading edge in which the rotor blade is operably coupled to a hub of a turbine includes circulating heated air through an outflow channel from the blade root towards the blade tip, recirculating the heated air via a return channel from the blade tip to the blade root, whereupon the recirculated heated air becomes returned air, and reheating the returned air for further circulation.

A device including a first discharge passage from a first rotor assembly to an engine, a first return passage that returns to an intake side of the first rotor assembly, a second discharge passage from a second rotor assembly to the engine, a second return passage that returns to an intake side of the second rotor assembly, and a pressure control valve whose valve main body is provided between a discharge port from the second rotor assembly and the first discharge passage. The first discharge passage and the second discharge passage are coupled, and a flow passage control is executed in each of: a low revolution range; an intermediate revolution range; and a high revolution range.

A surgical instrument has a channel dimensioned to receive a viewing instrument and enable the viewing instrument to be moved to or from a position near an optically transparent portion of a blunt, enclosed distal end of a shaft to provide unobstructed viewing through the distal end, and a position to the proximal side of an enclosed working area to provide viewing of the enclosed working area. A surgical instrument also or alternatively has a fluid routing switch within a shaft which can selectively connect a fluid infusion channel to at least one fluid export pore or a return channel. A method involves moving a viewing instrument to or from a position near an optically transparent portion of a blunt, enclosed distal shaft end and a proximal side of an enclosed working area. A method also or alternatively involves changing a position of a fluid routing switch within the shaft.

A nebulizer for efficiently and reliably delivering aerosolized fluid to an inhaling patient is disclosed. The nebulizer, in one embodiment, includes a fluid channel air inlet and fluid channel air inlet valve responsive to either a manual force external of the nebulizer, or a patient's breathing, to begin the nebulization process. The nebulizer also includes a fluid return channel to a fluid source, such as a removable vial, containing fluid to be aerosolized.

A compact heat pump system and a heat pump operation method, which can avoid the occurrence of surging in a compressor at startup of a heat pump and can directly supply vapor of a working medium produced by the compressor to an external heat-utilizing facility. The heat pump system comprises an evaporator for recovering heat of an external heat source to a working medium supplied as liquid water from the exterior via a water feed channel, thereby evaporating the working medium, a compressor for compressing the working medium evaporated in the evaporator and increasing temperature of the evaporated working medium, and a driving unit for giving motive power to drive the compressor. The heat pump system further comprises a supply channel for supplying, as a heat source, vapor of the working medium having temperature increased by the compressor to an external heat-utilizing facility, and a return channel branched from the supply channel and introducing the working medium discharged from the compressor to the evaporator.