What Are the Different Types of Amplifier Cables?

Cable television (CATV), also known as cable television, was developed from wireless television and first appeared in Pennsylvania, the United States in 1950. Cable TV still retains the broadcast system and signal modulation method of wireless TV, but does not change the basic performance of the TV system. Cable television sends recorded programs to users through cables (cables or optical cables), and then replays them on televisions without radiating electromagnetic waves into the air, so it is also called closed-circuit television. Cable TV is a pay-TV that is paid by viewers, not funders.

Cable TV, referred to as CATV (Cable Television), originally referred to as "Common Antenna Television", and now refers to all cable or fiber-optic copper hybrid systems used to transmit video signals to communities and homes. The earliest cable television service appeared in 1948, when the cable television network was used to realize simple retransmission of broadcast television programs. In the early 1980s, cable television networks achieved large-scale coverage worldwide. A cable TV network enterprise is an operating company that provides cable TV services to users.

Since the television signal is transmitted through the cable, it is not blocked by high mountains, etc., so the viewing quality is good.

Cable television can use adjacent frequency transmission. Unlike radio, which is considered to prevent interference, frequency separation must be used in an area, so spectrum resources can be fully utilized and more channels can be provided.

Cable TV can also realize two-way transmission of signals through cables, can provide interactive two-way services, and can easily implement charge management and carry out a variety of paid services.

Cable TV stations do not need expensive transmitters and huge iron towers, so the construction cost is low, which is conducive to rapid development.

The cable television system not only receives and rebroadcasts the programs of the large television network, but also provides its own recorded programs with different thematic content, providing subscribers with more program choices.

The TV system first appeared in the United States in the 1940s. The original system was used in apartment buildings with shared antenna televisions; residents in apartment buildings were not likely to install antennas on their roofs, so a shared antenna television system came into being. The shared antenna TV is very simple. It consists of a shared antenna TV amplifier installed near the main antenna and wired cables to the residents. Later, due to the development of high-power broadband amplifier technology, transmission ranges including a city

At present, the typical cable television system is mainly composed of the following four parts: the signal source part, the front-end equipment part, the main line transmission part and the user distribution part, as shown in the figure.

Signal source part

Broadband access network technology

With the increasing maturity of Internet technology, high-definition audio, video, image and other multimedia data transmitted through the network are constantly engulfing the limited channel bandwidth. Therefore, the cable TV broadband access network technology has undoubtedly become a hot spot today. This two-way broadband network access mode, which is based on cable television, has been accepted by more and more users due to its flexible application, fast speed, and low cost. It has become the current commercial household and Broadband access technology commonly used in private houses ^[3]

Generally, we divide the business of cable television networks into three categories, basic services, extended services, and value-added services ^[2] .

CATV value-added services

It is a multi-function service developed on the wired network, including Internet access, IP phones, video conferencing, bandwidth rental, and TV business. These new services will expand the service content of the cable network from TV to voice and data communications, finance, education and other fields, greatly expanding the business development space of the cable network. At present, the value-added services of the wired network are still in the development and trial stage in various regions, and the revenue is still very small, but its future potential is incalculable.

IP Cable IP Phone

After the cable television network is upgraded, the use of VOIP technology can provide very low-cost IP telephone services, reducing the telephone charges to one tenth of the current ordinary telephone charges. Traditionally, people have concerns about the quality of voice services provided by Cable. However, the development of DOCSIS technology has greatly improved the support of delay-sensitive services for wired networks, and improved the quality of service (QoS). Many new cable services TV operators already provide carrier-grade voice services. In the future, this service will have a major impact on Telecom's circuit-switched telephone business, but it is expected to become an important source of revenue for wired networks.

Cable TV Business

As one of the most important information media today, TV has the preliminary conditions for conducting business once it is connected with financial institutions and enterprises. Compared with e-commerce, TV commerce is more realistic and feasible, and has more room for development. Many consulting agencies predict that TV commerce will become a trillion-level industry within ten years. China has the world's largest cable television network and the largest number of cable television subscribers. It has unique conditions for launching a TV business, and its revenue is expected to reach more than 100 billion yuan within ten years.

Cable video conference

The use of cable television networks, through dedicated channels and recording and playback equipment, can provide video conferences with very smooth sound and images, enabling effective real-time communication between multiple points, and achieving communication effects that cannot be achieved under traditional technologies.

In addition to the above services, the value-added services of the cable television network also include distance education, telemedicine, remote securities trading, electronic automated meter reading and home security monitoring, television games, etc. These services also have huge room for development in the future.