Abstract: An apparatus and method is provided for permitting a service provider technician or subscriber to install a twisted wire pair to coax adapter within a network interface device (NID) at a subscriber premises. The twisted wire pair to coax adapter is configured for snap-in mounting within a NID. The adapter includes input and output connections, as well as an internally disposed balun, and is configured to convert communications signals carried on a twisted wire pair to communications signals carried on a coax cable to avoid degradation of the signals resulting from the use of an unshielded twisted wire pair within a subscriber premises.

Abstract: A signal amplifier circuit includes peak value holding circuit 11 receiving positive-phase input signal, peak value holding circuit 12 receiving negative-phase input signal, adder 13 adding the positive-phase input signal and output signal of peak value holding circuit 12, adder 14 adding the negative-phase input signal and output signal of the peak value holding circuit 11, non-inverting amplifier 15 amplifying output signal of adder 13, non-inverting amplifier 16 amplifying output signal of adder 14, peak value holding circuit 21 receiving positive-phase output signal of non-inverting amplifier 15, peak value holding circuit 22 receiving negative-phase output signal of non-inverting amplifier 16, adder 23 adding the positive-phase output signal and output signal of peak value holding circuit 22, adder 24 adding the negative-phase output signal and output signal of peak value holding circuit 21, and differential amplifier 29 amplifying difference between output signals of adders 23 and 24.

Abstract: An inverting adapter is disclosed that inverts inverted DVB-ASI signals to produce an adapted DVB-ASI signal. This adapted DVB-ASI signal may be used by any DVB-ASI device. The inverting adapter can be contained in one small package and easily connected to any of the various amplification devices that produce inverted DVB-ASI signals. Alternatively, the inverting adapter of the present invention may be integrally formed with an amplification device to automatically provide the adapted DVB-ASI signal.

Abstract: A system and method for spectral node splitting in cable TV network based on hybrid fiber-coax architecture is disclosed. Two-way optical signals carrying video and/or multimedia content are received at a signal distribution node. Portions of the received signals are processed according to the functionality the direction thereof. Certain frequency ranges are passed intact while specific different downstream and specific different upstream frequency bands are converted in a manner as to be allowed to be multiplexed into an extended broadband signal. The frequency bands within the extended broadband signal are distributed selectively among separate branches of the network. The frequency bands dedicated to the upstream traffic are received selectively from the separate network branches to be back converted and transmitted upstream to the network controller.

Abstract: An electronic apparatus according to the present invention includes two modules which decode high frequency analog signals. Furthermore, each of the modules is provided with an RF section at a position away from the center of the module in either longitudinal direction to carry out radio communications using high frequencies. In this electronic apparatus, the two modules are arranged so that their longitudinal sides extend parallel with each other in opposite directions. The two modules are also misaligned with each other in the longitudinal direction so that the RF sections lie away from each other and so that connectors to which signals subject to noise interference are inputted lie away from each other.

Abstract: Enhanced Cable Modem Termination System (CMTS) functionality, including programmable digital domain modulators and demodulators for dynamic channel assignment, is incorporated into Fiber Nodes (FNs) or mini Fiber Nodes (mFNs), yielding enhanced Fiber Nodes (eFNs). These eFns distribute CMTS functionality deep into Hybrid-Fiber-Coax Networks (HFCN) rather than centralizing the CMTS functions within a single location. Moving the cable modem terminations closer to the subscribers shortens the analog RF paths required to support cable modems. Communication of both subscriber data and CMTS control data is performed over Ethernet-compatible packet networks between the field-based CMTSs and an upstream facility (e.g., the Head End), which includes an Internet gateway. Packet data for multiple subscriber cable modems is easily compressed and merged over common network paths, reducing cabling plant complexity and increasing bandwidth utilization.

Abstract: An optical multiplexer is provided that operates in a synchronous optical network (SONET). The multiplexer includes a plurality of inputs and a processor operationally coupled to the inputs. The multiplexer also includes a plurality of optical outputs coupled to the inputs via the processor, wherein the processor is configured to receive data from at least two of the plurality of inputs. The processor is also configured to packetize the received data and route the packetized data to at least two of the plurality of optical outputs.

Abstract: A wireless communications system comprises a first splitter separating at least two signals, a wireless circuit for processing a first signal as a wireless signal and a combiner connected to the wireless circuit and the splitter, combining the two signals and transmitting the signals into a service area. The wireless communications system further comprises a second splitter separating the wireless signal from a second signal, and a transmitter for broadcasting the wireless signal.

Abstract: In a CATV trunk amplifier, a downward signal input to an input terminal from the center equipment side is input to a downward amplifying circuit via a first filter and a second filter. The amplified downward signal is output to the terminal device side via the second filter, the first filter, and an output terminal. An upward L signal is input from the terminal device side via the output terminal to an upward L amplifying circuit via the first filter and a third filter. The amplified upward L signal is output to the center equipment side via the third filter, the first filter, and the input terminal. An upward H signal is input to an upward H amplifying circuit via a fourth filter. The amplified upward H signal is output to the center equipment side via the fourth filter and the input terminal.

Abstract: For transmitting delay-critical data in a digital, time division form in an additional channel of a cable television system, the slots of the channel are further divided into smaller mini slots, for the indication of which the same cyclic indication is used as with which the superframes controlling the use of the channel indicate the original slots. A method based on mini slots is compatible with DAVIC 1.0 and 1.1 specifications.

Abstract: In order to correctly perform frequency conversion without using a pilot signal from an external system in a CATV system in which an upward signal is converted to a high frequency in-building upward signal using an up-converter and the in-building upward signal is converted to the original upward signal using a down-converter, there is proposed a down-converter provided with a reference oscillation circuit for generating a reference signal with a frequency lower than that of a downward signal or the in-building upward signal. The in-building upward signal is frequency-converted using the reference signal and the reference signal is transmitted to a transmission line of the terminal side. A bi-directional amplifier on the transmission line can not only amplify the downward signal and the in-building upward signal bi-directionally but also transmit the reference signal to an up-converter of the terminal side.

Abstract: A processor integrating and controlling at least two A/V devices by constructing a control model, referred to as a filter graph, of the at least two A/V devices as a function of a physical connection topology of the at least two A/V devices and a desired content to be rendered by one of the at least two A/V devices. The filter graph may be constructed as a function of at least two device filters corresponding to the at least two A/V devices, in which the device filters include certain characteristics of the at least two A/V device. These characteristics may include the input or output pins for each device, the media type that the A/V device may process, the type of functions that the device may serve, etc. The desired content may be received as a user input which is entered via a keyboard, mouse or other comparable input devices.

Abstract: A apparatus and apparatus for compensating for video insertion loss due to transmission over long twisted pair cable lines is presented. Transmission of video over twisted pair cable is advantageous because of its superior cost advantage over coaxial cable. However, twisted pair cables have significant loss characteristics at the higher frequencies (i.e., broadband) compared to coaxial cables. At a transmitter station, the video signal is amplified in the high frequency region for possible skin effect losses thereby brute forcing the high frequency components to the receiving station. At the receiver station, the video signal is further compensated for diffusion line and skin effect losses. The total skin effect compensation applied in both the transmitter and receiver stations is such that the square root of frequency characteristics of skin effect losses is compensated for.

Abstract: A reconfigurable node for a hybrid fiber cable network includes fiber slots housing a transmitter or receiver interfacing to a head end, coax slots housing an RF brick interfacing with subscribers and RF plug-in modules providing connectivity between the fiber and coax slots. The plug-in modules include connection points, for connection to a fiber or coax slot. A fiber impedance element, associated with the transmitter or receiver in that fiber slot, is connected to each fiber slot. Each fiber impedance element has a different impedance value. A coax impedance element, associated with the RF brick in that coax slot, is connected to each coax slot. Each coax impedance element has a different impedance value. An impedance sensing circuit detects a DC level associated with each connection point which corresponds with the impedance element in a respective fiber or coax slot to determine the location of transmitters, receivers or RF bricks.

Abstract: An amplifier (125) includes a gain stage (210) for amplifying a signal received by the amplifier (125). The amplifier (125) also includes an AGC circuit (400) that adjusts the amplification of the gain stage (210) and that includes a comparator (440) for determining whether the input signal is one of a digital pilot signal and one of an analog pilot signal. The AGC circuit (400) processes both digital and analog pilot signals and automatically adjusts the processing method depending upon the type of pilot signal.

Abstract: A two-way CATV system is easy of maintenance, stable of a transmission quality and capable of restraining inter-modulation distortion noises of downstream RF signal carriers which are caused by non-linearity of electric contact members of coaxial connectors among upstream ingress noises becoming a problem when performing communications services by utilizing a CATV transmission path. The two-way CATV system comprises at least one bidirectional amplifier provided on a CATV transmission path for connecting a CATV center station to a subscriber home, a bias voltage superposing element for superposing, with a bias voltage, a downstream signal transmitted along a coaxial transmission path subordinate to an amplifier at the terminal among the bidirectional amplifiers, and a bias current adjusting load element, provided at the end of the coaxial transmission path, for setting the bias current corresponding to an application of the bias voltage superposed by the bias voltage superposing element.

Abstract: A digital broadcast transmission/reception system includes a transmission posting apparatus for performing a communication call through a telephone line network before a broadcast transmission apparatus starts transmitting individual information. The system also includes a distributor having a register which stores a transmitter ID signal of the transmission posting apparatus. The distributor compares a transmitter ID signal at the communication call with the transmitter ID signal stored in the register, outputs a power control signal when these ID signals match, and connects the telephone line network with a telephone when these ID signals do not match. The system also includes a power control apparatus for tuning ON power to a broadcast reception apparatus according to the power control signal. Therefore, the power to the broadcast reception apparatus can be controlled through the telephone line network.

Abstract: An insertion box provides a plurality of input and output ports. Each input port corresponds with a predefined and unchanging set of output ports. Insertion of a signal into a particular input port results in that signal being delivered to each of the corresponding output ports. The dissemination functionality is performed by RF circuitry that is typically housed within the insertion box, and is interposed between the input ports and the output ports. The RF circuitry is composed of combiner circuits and splitter circuits. The RF circuitry is designed so that when a combiner is used as an input stage for a splitter, a transformer, usually used to convert an input or output impedance to match a characteristic line impedance, is eliminated. Elimination of such a transformer results in a concomitant reduction in signal loss.

Abstract: An addressable tap capable of detecting number of TV sets online to watch CATV programs consisting of a main block and a cable connecting from the terminal of said main block and the user. Said main block consists of a main central processing unit (CPU) and RF switches that are electrically connected is featured by: Said cable is equipped with a locking device at its user end and this locking device consists of a detection device and a sub-CPU that communicates with said main CPU; said detection device is electrically connected to the sub-CPU; In case said locking device is plugged out, the detection device will detect the information and transmit it to said microprocessor, which will send the information to said main CPU. Said main CPU will instruct the RF switches to shut off CATV signals at the terminal. the present invention has the following effects: CATV operators can collect different fees in accordance with number of TV sets online to watch TV programs and avoid income losses of CATV operators.

Abstract: A part of transmission signal is branched by a directional coupler, and split by a splitting circuit, so that the transmission signal can be outputted to the subscribers' terminal devices via branched output terminals. Latching relays disposed in signal paths to the branched output terminals from the splitting circuit can set the output/stop of the transmission signal to the terminal devices. A control circuit switches the connected/disconnected state of the relays in response to the command signal from the center apparatus. When an operation switch is turned on, all the relays are placed into the connected state. As a result, after the installation of the tap device, by operating the operation switch, the broadcasting signal can be distributed to the terminal devices before the command signal is received.

Abstract: A media control system comprises a memory accessible by a processor and a content manager stored in the memory and adapted to receive media content from a media source. The content manager is further adapted to automatically identify, from the received media content, primary media content for directing to a primary media device and ancillary media content for directing to an ancillary media device.

Abstract: The present invention provides an apparatus and methods for converting a legacy cable television subscriber passive tap into an enhanced addressable tap. The apparatus includes an addressable control module, one or more RF switch modules and a probe assembly. Additionally, a set of methods is provided for using the present invention to adapt an existing passive tap to an enhanced addressable tap.

Abstract: A digital television translator includes a digital television receiver for receiving a first digital television signal at a first frequency and generating a digital transport stream from the first digital television signal. The digital transport stream can include original Program and System Information (PSIP) data having RX channel data that is indicative of the first frequency, the first major channel number, and/or the first minor channel number. The digital television translator also includes a PSIP update module for updating the original PSIP data in the digital transport stream by replacing the RX channel data with TX channel data. The TX data is indicative of a second frequency, a second major channel number, and/or a second minor channel number.

Abstract: A power supply circuit in the tap device includes a first power supply circuit for generating a first power voltage of DC 24V to drive output switching relays, and a second power supply circuit for generating a second power voltage of DC 5V to be supplied to a receiving circuit and a microcomputer. The second power supply circuit lowers the voltage of the alternating-current power signal from the transmission line with a transformer, rectifies and smoothes the power signal with the lowered voltage, then generates the power voltage using a three-terminal regulator. The tap device can be used in CATV systems with different voltages of the alternating-current power signal employed, a power loss generated in the system with a high voltage is reduced, and the power consumption of the tap device can be suppressed.

Abstract: A feed signal equalizer for a feed amplifier for two-way coaxial cable systems, of the type having a distribution centre distributing feed signals, and having reception facilities for receiving return signals from said cable system, the system having feed amplifiers for receiving feed signals, and having return amplifiers, and the feed signal equalizers are settable to provide varying amplifier specifications, and having receptacles for receiving plug-in equalizer components for varying the specifications of the feed amplifier, the equalizer components having a range of varying performance characteristics so that a component can be selected and plugged in to the feed signal equalizer to produce the performance specifications desired at a predetermined location in the cable system.

Abstract: An adaptive high pass filter is used to reduce signal noise such as that occurring on a CATV upstream carrier. A signal detector senses a lowest active frequency on a CATV transmission. A high pass filter is then adjusted to cut off transmissions at frequencies below the lowest active frequency. This reduces ingress noise present in the upstream channel.

Abstract: Received digital CATV signals are branched by a directional coupler into signals flowing in a through direction and signals flowing in a branch direction. The signals output from the directional coupler in the through direction are then fed through an extraction circuit, a variable attenuator, and a wide-band amplifier so as to have a desired frequency range and a desired level, and are then fed to a distributor so as to be distributed, for output, into downstream signals to be fed to a downstream tuner and CATV signals to be fed to an analog/digital tuner. The signals output from the directional coupler in the branch direction are fed through a band-pass filter and a wide-band amplifier to a distributor so as to be distributed, for output, into VHF signals and FM signals. Upstream signals are fed through an extraction circuit to a terminal at which the CATV signals are received.

Abstract: A system that permits use of existing cable TV wiring for home networking is disclosed. Because of the presence of splitters, notch filters, and other components in the cable distribution system, certain of the premises installations in the system can locally communicate over the same frequency as one another, without interference. In a disclosed embodiment, the cable operator determines the attenuation and isolation among different premises in the system, and then assigns home network frequencies to the particular premises, with those premises installations that are sufficiently isolated from one another being assigned the same home network frequency.

Abstract: This invention provides a network relay apparatus has an information collecting portion for collecting information about the function and identification of devices V1-V4 in other network n1 through a communication channel N, a virtual unit generating portion for generating virtual unit information corresponding to a first protocol based on the collected device information, and a relay portion which receives a predetermined command from the first network and which transmits the predetermined command to the device in the second network based on the virtual unit information. Consequently, control of apparatuses among networks is facilitated.

Abstract: Complementary band-splitter and band-combiner devices and methods of operation of both are disclosed. Embodiments of the invention may allow wideband and narrowband functions and services to operate seamlessly by band-splitting wideband data into low-band data and high-band data. Narrowband data may comprise only low-band data. Wideband services may operate on both low-band and high-band data, while narrowband services may operate only on low-band data. Another embodiment of the present invention may include machine-readable storage having stored thereon a computer program having a plurality of code sections executable by a machine for causing the machine to perform the foregoing.

Abstract: A DSX system arranged to receive a plurality of high-density chassis is disclosed. The chassis include back planes having rear access IN/OUT fields and rear access cross-connect fields. The rear access IN/OUT fields are electrically connected to termination structures and panels located in respective IN/OUT regions and cross-connect regions. The termination structures of the IN/OUT region includes first and second fanning strips located along edges of termination panels. A double-hinged cover provides access to the termination panels.

Abstract: A communication system is provided which may comprise an upstream source of broadband communications and a downstream local area network, wherein the upstream source of broadband communications is coupled to the downstream local area network through a notch filter. In some embodiments, the upstream source of broadband communications may be a cable television service provider, and the local area computer network may use existing cable television wiring as communication cable.

Abstract: A broadband telecommunication network (such as a cable television distribution system) includes a plurality of switching units (such as taps) controlling subscriber access to the network. The switching units are controlled from a central location (such as a head end) using minimal network transmission medium power. A repeating sequence of switching unit control messages is sent from the central location across the network. Each of the messages is addressed to an individual one of the switching units. Each switching unit is periodically powered up from a low power sleep state to a higher power operational wake state in synchronization with a corresponding one of the control messages being sent from the central location. After a switching unit's corresponding control message is processed, the switching unit is returned to the lower power sleep state.

Abstract: A CATV system is provided that includes a head-end with laser transmitters to provide data to a multitude of nodes through a forward optical network tree. The nodes convert the optical signals into electrical signals and retransmit the television and data signals through a coaxial network tree to customer interface units (CIUs). The nodes include respective controllers which identify status signals from the equipment of the nodes and transmit the status signals and a reference signal to the head-end controller for display on a display of the head-end controller. The reference signal allows monitoring that the return optical transmitter and network are operating correctly and allows the return signals from the nodes to be aligned. The status signals from the nodes include laser operation, laser bias current and laser power output for the laser transmitters of the nodes.

Abstract: An electronic device for distributing broadcast signals in a cable broadcasting system includes a receiving circuit receiving broadcas signals including command signals and a microcomputer for controlling the electronic device according to the command signals. A watchdog timer counts an output s op period and compares with abnormality determining times. An output stop period is reset by a microcomputer pulse signal generated at constant intervals and representing normal operation of the microcomputer and an input stop period is reset by a periodic command pulse representing normal operation of the input from the receiving circuit to the microcomputer. The timer generates a microcomputer eset signal when a stop period exceeds an abnormality determining time.

Abstract: In a cable data system, frequency division multiplexed upstream data traffic is first split for subsequent signal processing. In the course of performing an analog RF signal splitting operation, signal splitter output amplitude is decreased as an artifact of an RF signal splitter. A signal splitter indicator type that is used per signal splitter, provides an indication to the CMTS channel interface cards to control the amount of compensating gain required to restore the original signal to its original amplitude.

Abstract: A digital interface apparatus and system for cable television systems and digital service are disclosed. The apparatus includes a housing with an input and two outputs. The housing includes a surge protection circuit connected to the input and to a signal dividing circuit that is connected to an output and a filtering circuit that is connected to another output.

Abstract: A multiple-room communication system is adapted to provide digital television programming (e.g. DBS) to a plurality of rooms in a single family dwelling and may be further adapted to provide digital television programming to a plurality of dwelling units in a multiple dwelling unit such as an apartment. A central unit includes a plurality of integrated receiver decoder modules that receive e.g. satellite signals from a satellite antenna and filter and supply the signals to a distribution system that is coupled to a plurality of display devices that are located in various rooms throughout the single family home. A plurality of hand-held remote controllers, each being associated with one of the integrated receiver decoder modules, are used to communicate with and control the associated integrated receiver decoder module to cause it to supply a desired signal to a desired display device.

Abstract: A processing apparatus for processing multiple video programs from one or more transport streams. The processing apparatus has a transport processing circuit that includes multiple transport processor units. The transport processor units utilize a common transport processor memory unit having demux context entries containing processing and hardware state information for packet types. Each transport processor unit includes a transport interface for identifying data packets to be acquired from the transport stream, a demultiplexing processor for processing the acquired data packets, and a demultiplexing DMA unit for memory handling operations ofthe processed data packets. Index chaining allows the transport processor units to access information from the transport processor memory unit. The method uses indices to access demux context entries from the transport processor memory unit. Related DMA indices are used to access memory handling information from the transport processor memory unit.

Abstract: A switch router and one or more gateways incorporating a diagnostic and calibration system that performs RF characterization of an underlying cable plant. The switch router is connected at a point of insertion or point of distribution and each gateway is located downstream, such as at corresponding subscriber locations. The switch router and each gateway sends a test signal with known characteristics and power level, and the receiving device determines noise level and power loss for the corresponding downstream and upstream channel pair. The power loss information is used to calibrate the power level of the transmitters. The noise levels are used to determine if the selected modulation schemes employed for normal communications is realizable. A frequency analysis, such as FFT or the like, is performed on the upstream test signal spectrum to derive valuable frequency information for the upstream channel or the entire upstream bandwidth.

Abstract: A non-interruptible tap has a non-interruptible member that is received in a lower part of the main housing and includes a support element, a pair of slide blocks, and a resilient conductive strip. The support element has holes at two ends, mounting on a first, and a second terminals respectively. The slide blocks are movably received in a slot formed between the end holes of the support element. The conductive strip is connected to the slide blocks with two ends sticking out beyond the same. The main housing further has an upper part, to which a circuit board is fitted. When the upper part is not joined to the lower part, e.g. it is removed for maintenance, the conductive strip can stretch to a normal straight shape to contact the first and the second terminals at two ends as to allow signals to be transmitted therethrough to the downstream line.

Abstract: An in-building CATV system having a down-converter for converting the in-building upward signal to the signal for a bi-directional CATV system provided with a high-pass filter disposed between an internal terminal and a converter for eliminating input of the downward signal passed through the downward signal path and selectively passing the in-building upward signal, a low-pass filter disposed between the converter and an external terminal for eliminating the downward signal inputted from the external terminal and selectively passing the upward signal outputted from the converter, a high-pass filter disposed between the external terminal and the downward signal path for eliminating input of the upward signal outputted from the converter and selectively passing the downward signal inputted from the external terminal and a low-pass filter disposed between the downward signal path and the internal-terminal for eliminating the in-building upward signal inputted from the internal terminal and selectively passing t

Abstract: A Cable Television (CATV) digital return link system that provides dedicated, high-speed, full-duplex and point-to-point connections between users and the head end system is disclosed. The CATV digital return link system includes return path transmitters, intermediate hubs and a head end hub coupled to each other via a network of fiber optics cables. The return path transmitters are each coupled to a relatively large number of users via a local CATV-subtree. Signals from cable modems are transmitted via the local CATV-subtree to the return path transmitters for transmission to the head end. A number of users are individually and directly connected to the return path transmitters. Data from these directly connected users is transmitted to the head end via the network of fiber optics cables in conjunction with the RF data from the subtree. Likewise, data from the head end to these directly connected users is transmitted in the forward path direction using the digital return link system.

Abstract: A standard, high performance CATV signal splitter that operates at high signal levels with greatly reduced intermodulation distortion. The circuit retains the presently accepted performance standards for RF signal splitters while reducing the unacceptable distortion resulting from the higher signal levels currently encountered in applications such as Internet communication. The improved signal splitter circuitry reduces or eliminates signal distortion due to magnetization of the ferrite core material. Such core magnetization occurs in prior art signal splitters when the high permeability ferrite core of the transformer is exposed to random electrical spikes, power surges, and static charge build-up. In the present invention, a tuned circuit is added in the output balance section of a prior art signal splitter to confine the transformer performance to the narrower range of CATV frequencies.

Abstract: A data transmission system is proposed, for example for video-on-demand, internet or multimedia applications, in which a number of subscribers in a building are connected to a central server through at least in part twisted pair cables within the building. Compensation for the channel distortion caused by the use of twisted pair cables is provided by the use of pre-emphasis filters in the outgoing data lines from the server. The required coefficients for the pre-emphasis filters are established by first characterizing the distortion properties of a channel by the use of a test signal.

Abstract: In a proposed cable broadcasting system in which a command signal transmitted from a center equipment to a transmission line for setting an operation mode of a tap device on the transmission line, the command signal can be transmitted without fail even when an instantaneous power failure occurs because of thunderbolt and the like. The center equipment transmits a command signal with a retransmission number indicating the number of transmission plural times at intervals of a time longer than the duration time of the instantaneous power failure. The tap device determines whether the new received data of the command signal is a command to the tap device itself by using the address of the received data. When the command is for itself, it is determined whether the command (received command) coincides with the command previously used for setting the operation mode. When they do not coincide with each other, the operation mode is set in response to the received command.

Abstract: An amplifier (125) includes at least one gain stage (210) for amplifying a signal received by the amplifier (125). The amplifier (125) also includes an AGC circuit (400, 500) that adjusts the amplification of the gain stage (210). The AGC circuit (400, 500) determines whether the input signal to the amplifier (125) is a digital signal or an analog signal and transforms either signal into the frequency domain, thereby automatically adjusts the processing method depending upon the type of pilot carrier signal. The AGC circuit (400, 500) also possesses the ability to process a change in the frequency of a pilot carrier signal remotely.

Abstract: A directional coupler system includes an input diplex filter for splitting an input signal into a high band signal and a low band signal, a high band directional coupler for which the high band signal is coupled to an input of the high band directional coupler, a low band directional coupler for which the low band signal is coupled to an input of the low band directional coupler, a tap diplex filter coupled to a tap of each of the high band directional coupler and low band directional coupler and an output diplex filter for receiving and combining a high band signal output from the high band directional coupler and a low band signal output from the low band directional coupler.

Abstract: There is disclosed a tap device for branching a part of transmission signals running through a transmission line to selectively transmit branched signals to subscriber terminal devices via tap output terminals, in which signal paths for leading the transmission signals to the tap output terminals can easily and securely be shielded. Substrates provided with various circuits and the like are successively fixed to a housing member provided with tap output terminals. The housing member is provided with partition walls for surrounding the signal paths to the tap output terminals from the first substrate and separating relays disposed on the substrate. A shield cover, which can separate wiring patterns for signal input to the relays and wiring patterns for signal output via the relays, is disposed between the first and the second substrates. The second substrate is fixed to the housing member via the shield cover.

Abstract: A telecommunications network is provided. The network uses a ring of ring switches to provide a transport mechanism for data packets that is transparent to the data and protocols contained in the data packets. This transport mechanism is simple and low cost to implement. Such networks can carry, for example, video signals between a primary site and secondary sites of a cable network to provide video on demand, near video on demand, distance learning and other video based services. Such networks can also provide telephony service as voice over IP.