IP multi-media access method and system for cable television

Abstract

The invention discloses an IP multi-media access method and an IP multi-media access system for a cable television. The method comprises the steps of frequency spectrum division, CIMA chip design and channel coding, wherein in the step of the frequency spectrum division, a frequency band between 1 and 60MHz is used, and comprises a tertiary structure, namely a sub-band, a sub-channel and a sub-carrier; the CIMA chip design adopts a CIMA protocol layer and a CIMA physical layer; and the channel coding comprises a pseudorandom sequence, forward error correction and interleaving. The system comprises a core network, an access network and a user network, wherein the user network is connected to the core network through the access network; and the core network comprises a public telephone backbone network, a cable television backbone network and an internet backbone network. The invention has the advantages of multiple function of a single wire, networking everywhere, function of a household mobile phone, low total cost, and high-speed access of an extensible platform to construct a home network.

Description

technical field [0001] The present invention mainly relates to the field of communication, in particular to a method and system for CATV IP multimedia access (CIMA). Background technique [0002] Since the construction of my country's cable TV network in the 1970s, there have been 13,000 kilometers of national trunk optical cable network. Since 1990, the development of cable TV has been extremely rapid. Basically every household in major, medium and small cities has cable TV cable in the house. Counties, towns and townships are also actively developing cable TV, and the development speed is very fast. . At present, our country has more than 300 million household users, and more than 170 million cable TV users, and the coverage of cable TV network still has a lot of room for development. The current cable TV network mostly adopts the hybrid network of optical fiber and coaxial cable (HFC) as the transmission medium, and the baseband of optical fiber and coaxial cable is rel...

AI Technical Summary

Problems solved by technology

The main disadvantage of DOCSIS: Uplink noise is a common problem, especially in real-time business situations such as video or IP voice, noise interference will cause data transmission delay and jitter, resulting in video image distortion or voice discontinuity

The main disadvantages of EOC: the low-frequency part is easily interfered by external noise; the number of terminals supported by each central office is relatively small, and the number of central offices needs to be increased in the case of multiple users, which also increases the cost

The main disadvantages of MoCA: the transmission distance is limited; the cable TV cable at home is required to have a high degree of connectivity (cables are required to go to each room), and the actual use is limited by certain objective conditions; although it can pass through the branch distributor, the working frequency is too high , there is too much attenuation, it is necessary to replace high-quality branch distributors and cables, and the adaptability to the network is weak

But at the same time, the serious problem of low-frequency noise interference must be considered

[0005] In the case that fiber-to-the-home (FTTH) cannot be realized soon, it is undoubtedly an economical and efficient choice to use cable television cables as the last mile access medium. Through the analysis of some existing transformation schemes, DOCSIS technology Mature, need to transform the existing line, the cost is high; MoCA uses high-frequency end, the transmission distance is relatively short, need to add a relay amplifier; EOC lacks a unified standard, the bandwidth used is relatively narrow, and the transmission rate is limited, therefore, need An access system that advances our national industry.

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