What Is a Cellular Repeater?

Cellular TV is a two-way broadband transmission technology that can transmit various image information to users' homes or business centers. The cellular TV system uses a multi-cell structure and operates in the microwave band of 27.5GHz-29.5GHz. ^[1]

Cellular TV is a two-way broadband transmission technology that can transmit various image information to users' homes or business centers. The cellular TV system uses a multi-cell structure and operates in the microwave band of 27.5GHz-29.5GHz. ^[1]

Chinese name

Cellular TV

Foreign name

Cellular TV

Design

Federal Communications Commission

Working frequency range

27.5-29.5GHz

Cellular TV Development Process

With the continuous development of cellular technology, the wireless television transmission technology has challenged the cable television (CATV) transmission technology, which has led to the emergence of cellular television based on cellular technology and microwave transmission technology.

In fact, "Wireless Cable" television technology has been developed for many years. As the Federal Communications Commission (FCC) announced that it would not treat "television companies as cable companies, so that it can transmit telecommunications and television services, this provides a good environment for the development of cellular television.

The impact of two-way broadband cellular systems on telephone services is profound. For example, in an area with a radius of 3 miles, the capacity of a cellular television system is almost 100 times that of a conventional cellular telephone system. In this area, the transmission power of each channel is only 10mw, and the signal-to-noise ratio is higher than that of a cellular phone system with a transmission power of 3W.

This cellular television system overcomes the effects of narrow frequency bands and high transmission rates. This is because the system's 1 GHz band can make millions of digital telephone calls simultaneously within a multi-cell cellular system. Because the cost of the system is lower than the cost required to connect to the user's home with an optical cable, it is conducive to the development of users' broadband services.

Currently, Cellular Vision is preparing to launch a variety of new video communications services such as multi-channel interactive television, wireless broadcast programs, high-definition television, conference phones and travel, banking, shopping, education and medical television to enable cellular television. The system is more attractive. ^[1]

Cellular TV Cellular TV System Principle

In December 1992, the FCC allocated the 27.5GHz-29.5GHz frequency band to point-to-multipoint broadcast transmission, thereby laying a foundation for the common network transmission of images, voice and data.

Cellular TV is a two-way broadband transmission technology, which can transfer various image information into the user's home or business center, and the cost of the system is only one tenth of the optical fiber TV transmission system.

The cellular TV system uses a multi-cell structure and operates in the microwave band of 27.5GHz-29.5GHz. The FCC has used 1 GHz for television transmission and the other 1 GHz for data and voice transmission. In the 1 GHz bandwidth, the system can transmit 49 TV channels, each of which includes a 20MHz FM broadcast signal. In addition, several communication channels can be inserted between TV channels. This arrangement doubled the number of TV channels so that more than 100 TV channels could be transmitted without compression technology.

In the central cell of the cellular television system, there is a source end (headend, which refers to a transmitting station that provides television programs and sends television signals to users). It uses satellite or microwave to send television signals to other communities. The omnidirectional transmitter in the central cell serves users in the central cell, and several other directional transmitters send television signals to other neighboring cells. There is also an omnidirectional transmitter in each adjacent cell to serve the users of the cell. Each user's home has a receiver or antenna and a TV pre-tuner. If the user terminal needs interactive data and voice communication, a receiver / transmitter should be configured.

The television program is transmitted to the central cell by the satellite ground station, microwave or studio through the local transmission system, and the source end in the central cell sends the television program to the neighboring cell through the point-to-point transmission link. These links also operate at 28 GHz. Each neighboring cell that receives a television signal will retransmit the television signals to other neighboring cells without adding a source or other program source. If you need to add or change TV programs, you can also add sources or other program sources in these neighboring cells.

Within each cell, those wireless signal shadow areas (or blind areas) are covered by low-power active relay stations or ground reflection systems (such as buildings). The FM broadcasting system in the cellular television system can use low-cost passive or active co-channel repeaters without interfering with the system, thereby achieving complete coverage of each cell. ^[1]