A service gateway provides a proxy between a client protocol and a plurality of standard communication protocols. The service gateway provides asymmetrical routing, data compression and encryption to optimize client processing power and communication link bandwidth. The service gateway enables content translation between clients and service providers. The service gateway keeps track of client available memory and sequence numbers in messages to generate error codes when applicable. A store and forward message capability is provided along with abstract session identifiers. The service gateway supports user datagram protocol.

Service gateway for interactive television

A computer is used to manage communication over a network between one or more network addressable units and a plurality of physical devices of a passenger entertainment system. The system is configured and operated using software to provide passenger entertainment services including audio and video on-demand, information dissemination, product and service order processing, video teleconferencing and data communication services. The system includes a system server and a network supporting multiple computer processors. The processors and the server comprise application software that control telephony applications and network services. The server is coupled by way of the network to physical devices of the system. The server comprises software that instantiates a network addressable unit server that interfaces to one or more network addressable units, that instantiates a services server that interfaces to one or more service clients that provide services of the passenger entertainment system, and that instantiates a router and one or more mail slots comprising a lookup table that identify each of the clients. Data comprising a network routing address and a physical device type are used to access the lookup table to determine message destinations. The respective servers interface to their clients by way of named pipes that translate messages from a first format to a second format. The server also comprises software that instantiates intranodal thread processors that route messages between processes on the physical devices and the one or more service clients to route services of the passenger entertainment system to the processes on the physical devices.

Transaction dispatcher for a passenger entertainment system, method and article of manufacture

A method for increasing channel utilization in a video broadcast system includes receiving, at a head-end, a request for a video program from one of a plurality of subscriber stations. Determining whether the requested video program is associated with a first subset of channels representing broadcasted channels having a first subscriber viewership level greater than a threshold level, a second subset of channels representing broadcasted channels having a second subscriber viewership level less than the threshold level, and a third subset of channels representing on-demand channels having a third subscriber viewership. The first subset of broadcast channels is substantially continuously transmitted. The second subset of broadcast channels is transmitted based upon channel availability and programming assignments. The third subset of on-demand channels are transmitted from the head-end to at least one of the plurality of subscriber stations upon assigning video programming corresponding to the requesting subscriber station.

Network bandwidth optimization by dynamic channel allocation

A television signal distribution system, comprising an antenna for receiving a composite microwave satellite signal having a plurality of television channel signals combined with a modulation and/or encoding format; and a network for distributing the composite satellite signal received by the antenna to each of a plurality of television receivers, such composite satellite signal being distributed as an optical frequency signal having the plurality of television signal channels combined with said modulation and/or encoding format prior to being fed to the television receivers.

Satellite distributed television

The present invention provides a satellite broadcast receiving and distribution system that will permit for the transmission of vertical and horizontal or left-hand circular and right-hand circular polarization signals simultaneously via a single coaxial cable. The system of the present invention will accommodate two different polarity commands from two or more different sources at the same time. This satellite broadcast receiving and distribution system of the present invention will provide for the signals received from the satellite to be converted to standard frequencies so as to permit for signals to travel via existing wiring which the present day amplifiers can transport in buildings, high-rises, hospitals, and the like so that satellite broadcasting can be viewed by numerous individuals by way of a single satellite antenna.

Satellite broadcast receiving and distribution system

Video signals for broadcasting service with a plurality of channels are frequency-multiplexed into a predetermined broadcasting band, and converted into optical signals by an optical transmitter. At the same time, video signals for VOD service requested by a plurality of subscribers are selected, taken out, frequency-multiplexed within the VOD band, and converted into optical signals by an optical modulator. These two types of optical signals are transmitted to subscribers through the optical network. In each subscriber's household, either broadcasting signals or video signals for VOD service are reproduced and desired programs are selected in the tuners.

Optical fiber cable service system provided with video on demand service

An optical transmission apparatus is provided which has an LD of single longitudinal mode. A bias current of the LD is set at its threshold current. A current obtained by amplitude modulation of a signal to be transmitted is superposed on the bias current. The LD is then set in the multimode, so that the apparatus can transmit a high-quality signal with reduced modal noise and distortion during multimode fiber transmission.

Optical transmission apparatus

A picture image distributing apparatus provided within a passenger moving vehicle, comprising a head end portion (1) for the FDM picture image signals of a multi-channel, an electric optical converting portion (2) for converting the FDM picture image signals into the optical signals, an optical amplifying portion (3) for optically amplifying the optical outputs, one optical fiber transmission path connected in column with optical taps (4) of non-equal distribution for branching a portion of the optical power, an equal or non-equal distribution optical tap (6) for branching at the final point of the optical transmission path, an optical electric converting portion (5) for receiving the branched or divided optical signals to convert them into electric signals, and passenger seat picture image receiving terminals (7) connected to the optical electric converting portion (5) to receive the electric signals.

Picture image distributing apparatus provided within passenger moving vehicle

A pay-channel transmission system for a CATV has an optical transmission unit and an optical receiver unit. The optical transmission unit includes pay-channel television signals optically multiplexed by a λ1 wavelength semiconductor laser and non-pay-channel television signals optically multiplexed by a λ2 wavelength semiconductor laser. The optical receiver unit includes an optical filter for filtering the λ1 wavelength data. Thus, a non-subscriber having the optical filter is prevented from receiving the pay-channel television signals, and a subscriber having no optical filter is able to receive both the pay-channel television signals and non-pay-channel television signals.

Pay-channel transmission system for CATV

An AM signal source frequency-multiplexes and outputs a plurality of AM signals. A soft clipper, which is formed by an amplifier or the like, nonlinearly loosely limits a large amplitude portion (impulsively changed portion) of the frequency-multiplexed AM signal by using its saturation property. Thereafter, an attenuator performs level adjustment for setting the signal at a prescribed degree of optical modulation. On the other hand, a 16QAM signal source frequency-multiplexes and outputs a plurality of 16QAM signals having different carrier frequencies. A frequency multiplexing part further frequency-multiplexes the AM multiplex signal with the 16QAM multiplex signal. An optical transmitter intensity-modulates a laser output beam with the frequency multiplex signal from the frequency multiplexing part and transmits the same. No clipping distortion occurs at this time. An optical signal from the optical transmitter is transmitted to a receiving system through an optical fiber member and is demodulated.

Hiroaki Nakata

Papers

Optical fiber cable service system provided with video on demand service

Optical transmission apparatus

Picture image distributing apparatus provided within passenger moving vehicle

Pay-channel transmission system for CATV

Optical transmission unit