Types/advantages and disadvantages of repeaters, how do repeaters work?

I. What is a repeater?

A repeater is a network device that retransmits a received signal at a greater strength than the original signal and retransmits it across a larger geographic or topological network boundary.

Repeaters are used in computer networks to increase network coverage, replicate weak or interrupted signals, and/or support remote nodes. Repeaters amplify received/incoming signals to a higher frequency domain, making them reusable, scalable, and usable.

Repeaters were first used in wired data transmission networks to overcome the limitations of signal propagation over longer distances, and now they are widely used in wireless networks to increase cell size.

Repeaters are often called signal boosters.

2. Types of Repeaters

2.1 Telephone Repeater

This is used to extend the transmission range of the telephone signal in a telephone connection.

Fixed telephone repeater

They are most commonly found on trunk lines that carry long-distance telephone calls. An analog telephone line consists of two wires and an amplification circuit constructed from a transistor that uses power from a DC current source to boost the power of an AC audio signal on the line. The wire pair carries two audio signals, one in each direction, because the telephone is a duplex (two-way) communication device. Therefore, telephone repeaters must be bilateral, amplifying the signal in both directions without generating feedback, which greatly complicates their construction. Telephone repeaters were the first type of repeater, and they were used in some of the earliest amplification applications. The introduction of telephone repeaters between 1900 and 1915 made long-distance telephone service possible. Most telecommunication cables today are fiber-optic cables with optical repeaters (below).

Before the invention of electronic amplifiers, mechanically connected carbon microphones were used as amplifiers for telephone repeaters. After the turn of the twentieth century, it was discovered that negative resistance mercury lamps could be used for amplification and this was utilized. Around 1916, the advent of the listening tube repeater made transcontinental telecommunications possible.

In the 1930s, vacuum tube repeaters with hybrid coils became common, allowing the use of thinner cables. In the 1950s, negative impedance gain devices became more common, and the E6

The repeater is a form of transistor and was the last major type employed in the Bell System until the low cost of digital transmission made all voice-band repeaters obsolete. From the mid-to-late twentieth century, the frog repeater was common in frequency-division multiplexing systems.

Submarine cable repeater

This is a telephone repeater used in undersea telecommunications cables.

2.2 Optical Communication Repeater

This is used to extend the signal range of a fiber optic cable. Short pulses of light transmit digital information through a fiber optic cable. Light consists of particles called photons, which can be absorbed or scattered in the optical fiber. Phototransistors convert the light pulses into electrical signals, amplifiers amplify the signal, electronic filters reshape the pulses, and lasers convert the electrical signals back into light and send it to another optical fiber in an optical communication repeater. However, optical amplifiers for repeaters are being created to amplify the light without first converting it into an electrical signal.

2.3 Radio Repeater

This is used to increase the range of radio signals. The history of radio relay repeaters began in 1898 with Johann Matausch.

Mattausch published an article in the Austrian journal Zeitschrift für Elektrotechnik (pp. 16, 35 -

36). However, his concept of a "translator" is crude and unsuitable for use.

Guarini-Foresio designed the first relay system with radio repeaters that actually worked in 1899.

A radio repeater typically consists of a radio receiver and a radio transmitter. To provide coverage beyond obstruction, the received signal is amplified and retransmitted, usually at a different frequency. The installation of a duplexer allows the repeater to use one antenna for both reception and transmission.

Broadcast repeater, retransmitter or converter: A repeater is a device that extends the coverage of a radio or television transmission station. It consists of a second radio or television transmitter. The signal from the main transmitter is often transmitted through leased telephone lines or microwave relays.

Microwave relay: This is a specialized point-to-point telecommunications link consisting of a microwave receiver that receives information from another relay station within line of sight via a microwave beam, which transmits the information to the next station via another microwave beam. Microwave relay networks carry telephone conversations, television programs, and computer data from one city to another.

Passive Repeater: This is a type of microwave repeater which is just a flat metal surface that reflects the microwave beam in different directions. It is used to send microwave relay signals over hills and mountains when amplification is not required.

Cellular Repeater: This is a radio repeater used to improve cell phone reception in a small area. The gadget works like a microcell base station and includes a directional antenna to receive signals from neighboring cell towers, an amplifier, and a local antenna to rebroadcast the signal to neighboring cell phones. This is common in downtown office buildings.

Digipeater: A packet wireless network repeater node. It performs a store and forward function, sending packets of information from one node to another.

Amateur radio repeater: Amateur radio operators use this to provide two-way communications across areas that would otherwise be difficult to reach using point-to-point coverage on VHF and UHF. Individual operators or clubs set up and maintain these repeaters, which are generally available to any licensed amateur. A hill or mountaintop location is desirable for building a repeater because it maximizes reach over a wide area.

Radio repeaters improve communication coverage in systems that normally use line-of-sight propagation frequencies. Without repeaters, the curvature of the earth and the blocking effects of terrain or tall buildings limit the range of these devices. A repeater on a mountaintop or tall building allows stations that cannot see each other to communicate consistently.

Radio repeaters can also allow conversion from one set of radio frequencies to another, allowing two separate public service agencies to communicate with each other (for example, the police and fire departments of a city, or a neighboring police department). They can also provide connection to the public switched telephone network or satellite networks (BGAN, INMARSAT, and MSAT) as an alternative means of getting from source to destination.

Repeater stations typically listen on one frequency, A, and transmit on another frequency, B. All mobile stations listen on channel B and repeat on channel A.

The difference between the two frequencies is negligible compared to the operating frequency (e.g. 1%). A repeater station will often use the same antenna for both transmission and reception; a highly selective filter called a "duplexer" separates the weak incoming receive signal from the billions of times stronger outbound transmit signal. Separate transmit and receive stations are typically used, connected by a wire or radio link. While repeaters are designed to receive and transmit simultaneously, mobile units do not require bulky and expensive duplexers since they are only either transmitting or receiving at any one time.

A "talkback" channel can be provided to mobile units in a repeater system, allowing direct mobile-to-mobile operation on a single channel. This feature can be used if the repeater system is out of range, or for communications that do not require the attention of all mobiles. The repeater output frequency can be the "talkback" channel; the repeater will not retransmit any signal on its output frequency.

Engineers will examine the intended coverage area and select repeater locations, heights, antennas, operating frequencies, and power levels to provide predictable, reliable communications within the designed coverage area.

3. How does a repeater work?

Repeater action is similar to a relay race. The transmitting station passes the signal to the repeater, which receives the signal and sends it to the receiving station. Since you press the transmit button to communicate and the release button to receive, only one side of the conversation can be heard at a time.

The diagram below depicts the gear used to operate the repeater and the path the signal takes. Here is a brief description of the components:

How do repeaters work?

Antenna: Most repeaters use a single antenna for both transmitting and receiving. Generally, it is a high performance, long lasting, and efficient omnidirectional antenna. They are placed as high above the ground as possible.

Feedline: Repeaters use hardwire, a sturdy, low-loss cable. In effect, it resembles a flexible pipe with a center conductor instead of a cable. Because hardwire has lower signal loss than traditional coaxial cable, more transmitted power reaches the antenna and the repeater can pick up weaker signals.

Duplexer: A duplexer distinguishes and isolates incoming and outgoing signals. It prevents the receiver and transmitter from interfering with each other and helps suppress particularly strong adjacent frequencies or other RF interference entering the repeater system. A duplexer usually consists of two parallel bandpass filters. There is no direct connection between the transmitter and receiver because one filter provides a path between the transmitter and the antenna and the other filter provides a path between the antenna and the receiver.

Receiver: A repeater receiver is usually very sensitive and selective, capturing signals that would be lost if sent directly from radio to radio. It is configured to receive an incoming frequency from a radio transceiver.

Controller: This is the brain of the repeater and is actually a dedicated computer. It manages the repeater station IDs via CW or voice and activates repeaters as needed. It is also used for various other purposes such as making pre-programmed announcements or connecting many repeaters.

Transmitter: The transmitting portion of most repeaters consists of an exciter and a power amplifier. The exciter retransmits the received audio at the correct frequency, while the power amplifier amplifies its output.

A repeater is a network device that retransmits data and diverts the signal to weak network access points. Data transmission and reception have different frequencies on both the sending and receiving ends. When the frequencies of the sender and receiver match, the repeater will operate.

Let's look at an example to learn more about repeaters.

Many of you might have heard of the word walkie-talkie. Walkie-talkies have a direct connection. Data can be transmitted to the receiver without any congestion or errors. Data can be transmitted only if there are no obstacles in the way of transmission. Let’s dive deeper into this topic. Suppose a person is communicating with another person through a one-to-one communication device such as a walkie-talkie. If there is a clear path between the distances, the data can be sent successfully. If there are peaks or hills on the way, the data cannot be delivered precisely.

An antenna is installed between the two devices to avoid this problem. The device retransmits the data to the receiver side and directs the signal to the weak point. This is called the main function of a repeater.

Please let us know how the repeater system works. The data passed from the sender to the receiver is called uplink, while the receiver retransmits the same data in another way and sends it to the receiver is called downlink. However, these repeaters can also be used in areas where there are no mountains or hills. We think the report is very powerful radio.

We have a variety of portable repeaters, more than 25

Watt mobile devices are more powerful. These repeaters are stationed in specific geographical locations. Most of these routers have a range of 50 to 100 watts, and some cable connectors are connected to the repeaters in fixed locations, such as on the top of a building tower or residential building.

Thanks to the presence of repeaters, all mobile or portable devices can access various communication signals in all directions. These receptors provide widespread communication for a larger area.

4. Characteristics of Repeater

These repeaters are linked together at the physical layer.

It transmits the signal to a weaker place to boost the system signal.

These receivers connect to various network signals to transfer data between two devices.

These repeaters can bridge the gap between two devices.

A repeater continuously monitors the signal generated between two LANs.

Electrical signals become weaker as they travel longer distances. These repeaters arrive at the location to strengthen the weak signals used in data transmission.

Repeaters can help achieve flexible networking.

The 30 repeaters connected to it are supported by the multi-site connection option.

All repeaters are linked together via an IP site connection network.

This IP network can quickly respond to any problems in the repeater network.

These receptors are capable of providing 100% digital communications. Therefore, they do not have to wait for analog voice calls.

5. Advantages of Repeaters

Repeaters are easy to set up and can be used to extend the length or coverage area of ​​a network.

They are cheap.

Repeaters do not require any processing overhead. The only time you need to investigate is when performance is impacted.

They can connect signals via various cables.

6. Disadvantages of Repeaters

Repeaters cannot connect different networks.

They cannot distinguish between real signals and noise.

They cannot minimize network traffic or congestion.

Most networks limit the number of repeaters that can be deployed.

7. Use of Ethernet Repeater

Repeaters are used to increase signal length and efficiency, so they are used more in Ethernet.

The main purpose of an Ethernet repeater is to transmit the signal from one Ethernet cable to another without attenuation or loss of signal strength.

The repeater system helps in detecting collisions. If a repeater detects a collision, it sends a signal to all the involved ports.

A repeater is a device that connects many Ethernet segments together. This is usually done with a multi-port repeater.

If there are more than five network segments between two host devices, the repeater will usually identify an incorrect link; in this case, the data flow will be interrupted until the Jat's data is corrected or repaired.

Repeaters are intelligent devices that regulate and control the flow of signals. To protect wires from damage or breaks.

Repeaters also allow the network segments to continue functioning even if one of the segments is down or unable to perform any functions. Hence, repeaters are very beneficial to the seamless functioning of a wired network.