Scientific-atlanta, Inc.

Cisco Technology, Inc.

John Skrobko

Hang Jin

John T Chapman

Alon Shlomo Bernstein

Tong Liu

John Alexander Ritchie, Jr

Pawel Piotr Sowinski

Robert R Riggsby

Saleh R Al-Araji

De Fu Li

Walid Kamali

Huang Ping

John Holobinko

Automated intelligent node setup and configuration in a Hybrid Fiber-Coaxial (HFC) Network may be provided. First, a desired operating profile for a node connected in a Hybrid Fiber-Coaxial (HFC) network may be determined by a computing device. Next, based on the desired operating profile, a setting for at least one component in the node may be determined by the computing device. Then the at least one component in the node may be adjusted remotely by the computing device to the determined setting.

Automated intelligent node for hybrid fiber-coaxial (HFC) networks

Presented herein are techniques for detection and avoidance of interference in a telecommunications network. In one example, a cable modem termination system (CMTS) is configured to receive upstream traffic from a plurality of cable modems. The CMTS detects collision characteristics resulting from substantially simultaneous transmissions from different combinations of the cable modems. Based on the detected collision characteristics, the CMTS designates/identifies collision groups for each of a plurality of the cable modems. After designation of the collision groups, the CMTS schedules upstream transmissions by the plurality of cable modems such that cable modems within the same collision group do not transmit within a same time frame and such that two or more cable modems that are not within the same collision group may transmit within a same time frame.

Interference detection and avoidance in a telecommunication network

A method for use in an RFoG cable network calls for allocating upstream bandwidth to CM devices, wherein allocating bandwidth includes selecting a start time and allocating respective time slots relative to the selected start time to at least one of the requesting CM devices; and further, allocating the same timeslots over multiple selected upstream channels, thereby aligning upstream transmissions from the requesting CMs across the selected upstream channels. Several embodiments are disclosed to enable DOCSIS 3.0 type scheduling over an RFoG network.

Scheduling for RF over fiber optic cable [RFoG]

The present invention is directed towards an optical receiver including an open loop automatic gain control (AGC) circuit. Optical signals received by the optical receiver are converted to electrical signals via a photodiode. The electrical signals are subsequently amplified through an input and an output amplifier stage. The amplified signal is then converted to RF signals and provided to an output port for further transmission. Concurrently, the AGC circuit senses the input optical power level at the input photodiode. The input optical power level is compared with a reference voltage, thereby providing a difference voltage. The difference voltage is applied to input and output amplifier stages for correcting the electrical signals to ensure a constant output power level.

Optical receiver having an open loop automatic gain control circuit

The present invention provides several embodiments of a video carrier signal detection circuit included in an optical transmitter for either disabling an oscillator that provides dithering tones or attenuating the power level of the dither tones. A first detection circuit detects the presence of a video carrier signal by analyzing a known video channel. The power level of a video sync pulse included in the known video channel is then compared to a reference power level. A second detection circuit compares the composite power level of the RF signals in a predetenmined frequency spectrum with a reference power level to determine either the presence of a video carrier signal or an increase in the channel loading. Upon detection of a video carrier signal or an increase in composite power, an enable signal is provided to either the oscillator or an attenuating device depending upon the detection circuit.

Laser modulation control to improve system dynamic range

A fiber-to-the-home (FTTH) system transmits forward and reverse optical signals, such as video, voice, and data signals, via optical fiber, and includes a plurality of home network units. The home network units include an FTTH optical receiver for receiving at least one of the video, voice, and data signals. A triplexer distinguishes and separates the video, voice, and data signals, wherein the video signals have a first wavelength and the voice and data signals have a second wavelength. The voice and data signals are provided to the home network unit for further processing. The triplexer provides an electrical signal to the amplifier stages. The amplifier stages include a preamplifier stage and a postamplifier stage. A gain control circuit automatically adjusts the gain of the video signal based upon the input power level to the FTTH optical receiver. Additionally, a tilt network performs level compensation for externally located coaxial cable. A video signal is then provided to a video device located within a home via the coaxial cable.

Fiber-to-the-home (FTTH) optical receiver having gain control and a remote enable

A fiber optic status monitoring system for a fiber optic cable television system is disclosed in which a computer serially polls a plurality of optical transmitter modules, optical receiver modules, or other cable television component modules to determine their operation. Each of the monitored components at a given location are connected together together by a common bus. In addition, each of the transmitter modules and the receiver modules include a monitoring/control unit. The computer transmits a command signal to an interface unit. The interface unit transmits the command signal to the transmitter modules via a bus. The command signal is modulated at the interface unit and transmitted over a bidirectional link. The modulated command signal is received and demodulated by a status monitoring interface unit. The status monitoring interface unit distributes the command signal to each of the monitored modules at that location. If the command signal is a query command signal, a monitoring unit transmits information on the operation of the module. If the command signal is a control command signal, a monitoring unit serves to supply control signals to the module.

Fiber optic status monitoring system

An improved optical receiver for an optical signal amplitude modulated with broadband RF signals is described. The optical receiver includes an optical detector which receives the optical signal and generates a radio frequency electrical signal which varies with the intensity level of the incoming optical signal. The electrical signal is applied antiphased from the optical detector to a pair of cascode transimpedance amplifiers which are coupled in a push-pull relationship. The coupling from the optical detector is matched to each of the inputs of the cascode amplifiers. Bias networks are used for each amplifier to maintain the gain stability of the receiver and to provide better output impedance matching to a coaxial cable for CATV distribution. The optical receiver can provide greater output power for the same input power because of the shared bias currents of the cascode stages in each amplifier.

Growing community of inventors

Berkeley Lake, GA, United States of America

John Skrobko