摘要:
Embodiments of a digital up-converter and an N-channel modulator are provided herein. The embodiments of the digital up-converter, in combination with the N-channel modulator, are capable of efficiently filling the spectrum of one or more RF signals with one or more types of information signals. For example, the digital up-converter can fill the spectrum of one or more RF signals with both broadcast and narrowcast video and data signals. In addition, the digital up-converter is capable of flexibly mapping the information signals to one or more channels of the one or more RF signals using a novel, three-level switching architecture.
摘要:
Embodiments of a digital up-converter and an N-channel modulator are provided herein. The embodiments of the digital up-converter, in combination with the N-channel modulator, are capable of efficiently filling the spectrum of one or more RF signals with one or more types of information signals. For example, the digital up-converter can fill the spectrum of one or more RF signals with both broadcast and narrowcast video and data signals. In addition, the digital up-converter is capable of flexibly mapping the information signals to one or more channels of the one or more RF signals using a novel, three-level switching architecture.
摘要:
Embodiments enable a network operator to use any (and a single) network management system (NMS) that it desires to manage a network having mixed fiber to the home optical network units (ONUs) and coaxial connected cable modems. For example, embodiments enable a cable company operator to use a DOCSIS (Data Over Cable Service Interface Specification) NMS (which the cable company already uses to manage its DOCSIS network) to manage such mixed network, by a simple addition of a DOCSIS Mediation Layer (DML) module between the NMS and the optical line terminal (OLT). On the other hand, embodiments enable a telephone company operator to use a standard EPON (Ethernet Passive Optical Network) OLT NMS with minor OLT and OAM (Operations, Administration, and Maintenance) protocol modifications to manage the same mixed network.
摘要:
A method, system and computer program product for creating dynamic custom headers and for controlling flow rate of Downstream External Physical layer Interface (DEPI) packets are described herein. The method comprises concatenating or fragmenting a packet descriptor of a DEPU packet based on one or more of associated packet size, maximum transmission unit, packet type, channel configuration information and flow control mode. The method further comprises creating a header for the packet based on data in a programmable header template and storing the header in a header buffer, determining whether to transmit the packet based on one of a flow meter or a maximum transmission unit size and transmitting the packet by sending the packet descriptor to an output direct memory access (DMA) controller. A flow meter flow control mode determines if a packet is to be transmitted based on packet size, bucket size, a low threshold and a high threshold. A maximum transmission unit flow control mode determines if a packet is to transmitted based on packet size and a maximum transmission unit size. The header can be customized for Packet Streaming Protocol (PSP) mode or Moving Picture Experts Group Transport Stream (MPT) mode and includes dynamic customizable fields such as User Datagram Protocol (UDP) port identification, flow identification and session identification.
摘要:
An downstream external Physical Layer (PHY) interface between a network and an edge quadrature amplitude modulator (EQAM) is provided. The interface comprises, an input direct memory access (DMA) controller enabled to control rate of packets received from the network, a plurality of buffers to store received packets, a first module enabled to convert packets to a first format and a second module enabled to convert packets to a second format. The interface further comprises a plurality of processors enabled to customize an output format of packets based on instructions stored in an instruction memory and a plurality of flow meters enabled to determine an output rate for packets based on, at least in part, a modulator rate of the EQAM. An output DMA controller controls the rate of egress of packets to the EQAM.
摘要:
A system for spur cancellation comprises an input, an output, a memory, and a summer. A value corresponding to an energy level of a spur is stored in the memory. The summer is configured to receive an input signal from the input, to receive the value from the memory, to subtract the value from the input signal, and to convey an output signal to the output. The output signal is a difference of the value subtracted from the input signal.
摘要:
Embodiments enable an Ethernet over Coaxial (EoC) Coaxial Media Converter (CMC) that implements only a subset of the functions (e.g., MAC and PHY) of a cable modem termination system (CMTS). The CMC sits between an optical line terminal (OLT) and a plurality of cable modems (CMs) that it serves. From the network management side at the OLT, the CMC appears and can be managed like an optical network unit (ONU). From the subscriber side, the CMC provides the same connectivity functions to the CMs as a CMTS and serves to terminate coaxial connections from the CMs.
摘要:
A method, system and computer program product in a downstream line card of a Cable Modem Termination System (CMTS) for managing downstream traffic for channels and bonded channel groups is provided herein. The method comprises the step of receiving packets for transmission to cable modems and classifying each packet to a flow based on class of service associated with the packet. The method further includes the step of storing the packets in flow queues based, wherein a flow queue is selected based on a flow a packet is associated with and wherein each flow corresponds to a single flow queue. The method also includes transmitting the packets from the flow queues to channel queues or bonded channel queues using corresponding channel nodes or bonded channel nodes at a rate that is determined based on feedback data and scheduling downstream transmission of packets on a single downstream channel if the packet is stored in a channel queue and on multiple downstream channels that are bonded together to form a bonded channel group if the packet is stored in a bonded channel queue. The feedback data is adjusted for each channel node or bonded channel node based on a queue depth for a corresponding channel queue or bonded channel queue.
摘要:
Embodiments enable a network operator to use any (and a single) network management system (NMS) that it desires to manage a network having mixed fiber to the home optical network units (ONUs) and coaxial connected cable modems. For example, embodiments enable a cable company operator to use a DOCSIS (Data Over Cable Service Interface Specification) NMS (which the cable company already uses to manage its DOCSIS network) to manage such mixed network, by a simple addition of a DOCSIS Mediation Layer (DML) module between the NMS and the optical line terminal (OLT). On the other hand, embodiments enable a telephone company operator to use a standard EPON (Ethernet Passive Optical Network) OLT NMS with minor OLT and OAM (Operations, Administration, and Maintenance) protocol modifications to manage the same mixed network.
摘要:
Embodiments enable an Ethernet over Coaxial (EoC) Coaxial Media Converter (CMC) that implements only a subset of the functions (e.g., MAC and PHY) of a cable modem termination system (CMTS). The CMC sits between an optical line terminal (OLT) and a plurality of cable modems (CMs) that it serves. From the network management side at the OLT, the CMC appears and can be managed like an optical network unit (ONU). From the subscriber side, the CMC provides the same connectivity functions to the CMs as a CMTS and serves to terminate coaxial connections from the CMs.