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

A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305) for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).

Digital optical transmitter

A CATV station apparatus subjects received optical signals to processes such as optical-electrical conversion, signal separation, coupling, and demodulation for obtaining an uplink signal. A received photocurrent monitoring section compares a received photocurrent at a optical receiving section with a predetermined reference current. If the received photocurrent is equal to or higher than the reference current, an amplifying section amplifies a signal output from a signal separating section at a predetermined level. If the received photocurrent is lower than the reference current, on the other hand, it is determined that a non-linear phenomenon, such as stimulated Brillouin scattering, has occurred in an optical fiber. The amplifying section then outputs a signal at a level which does not affect, even after being coupled with other signals, communications performed by other optical transmission systems.

CATV uplink optical transmission system

Devices and methods for equalizing the gain of an optical amplifier are described. For devices including harmonic filters that are controllable by amplitude control voltages and phase control voltages, techniques for controlling the amplitude control voltages and phase control voltages are presented. Additionally, device architectures are described by which an incoming optical signal is equalized to compensate for uneven gain in prior amplifiers or other optical components, and in which the incoming optical signal is received at a beam displacer and separated into orthogonal component beams, wherein the beams are counter-propagated through the equalizer in opposite directions through the same spatial path so as to minimize or eliminate the effects spatially dependent imperfections in the equalizer.

Optical harmonic equalization control systems and methods

A system for transmission on an optical link by modulating an optical carrier suitable for video-communication cable networks, includes devices for increasing the modulation of the optical carrier, such as increasing the intensity modulation. The system is particularly suited for the case in which a high input optical power is coupled into the optical link. Also, the modulation can be increased from a null value if the modulation is other than intensity modulation, in order to prevent or to reduce phenomena degrading transmission quality associated with the Brillouin effect.

Optical transmission system suitable for video-communication cable networks

An optical transmission system

Systeme de transmission optique, notamment pour reseau câble An optical transmission system, in particular for wired network de videocommunication Ce systeme de transmission sur une liaison optique, par modulation d'une porteuse optique, notamment pour reseau câble de videocommunication, est essentiellement caracterise videocommunication This transmission system on an optical link by modulating an optical carrier, in particular for videocommunication cable network, is essentially characterized en ce que, notamment pour le cas de forte puissance optique d'emission, a coupler dans ladite liaison optique, il comporte des moyens (9, 10, 11, 12, 13) pour augmenter, si necessaire, le taux de modulation de la porteuse optique, eventuellement a partir de la valeur nulle dans le cas ou in that, in particular for the case of high transmission optical power to be coupled in said optical link, it comprises means (9, 10, 11, 12, 13) to increase, if necessary, the modulation rate of the optical carrier, optionally from the value zero in the case where ladite modulation est une modulation autre qu'une modulation d'intensite, de facon a eviter, ou a limiter, les phenomenes de degradation de la qualite de transmission lies a l'effet Brillouin. said modulation is a modulation other than intensity modulation, so as to avoid, or limit, the degradation phenomena of the transmission quality associated with the Brillouin effect.

Cretin Yves

Papers

Optical transmission system suitable for video-communication cable networks

An optical transmission system

Optical transmission system, particularly for a video communication cable network