Transmission medium is the medium or device used to facilitate the connection between the sender and receiver of information (in this case data), because of the long distance. First the data is converted into code and this code will be manipulated in various ways to be converted back into data.
Some electronic devices, such as telephones, computers, television, and radios require transmission media to receive data. As in a telephone, the transmission medium used to connect two telephones is a cable. Every electronic device has different transmission media in sending data.
- Types of electronic devices
- The data used by these electronic devices
- The level of effectiveness in sending data
- Size of data transmitted
To get to know more about transmission media, below are several types of transmission media, namely as follows:
1. Twisted Pair Cable
Twisted pair cable consists of two conductors that are joined in order to reduce or eliminate external electromagnetic interference such as electromagnetic radiation from unshielded twisted-pair (UTP) cables, and crosstalk that occurs between adjacent cables.
There are two kinds of Twisted Pair Cable, namely:
STP and UTP (Shielded Twisted Pair) cables are one type of cable used in computer networks. This cable contains two pairs of wires (four wires), each pair twisted. In the STP cable the attenuation increases at high frequencies causing crosstalk and signal noise.
UTP (Unshielded Twisted Pair) cables are widely used in computer network installations. This cable contains four pairs of wires, each twisted pair. UTP cables are very susceptible to the effects of electrical interference from the surrounding media.
2. Coaxial Cable
For this type of transmission medium, I have posted an article regarding this coaxial cable before. For more details, please read the explanation regarding the coaxial cable.
3. Fiber Optic
Optical fiber or optical fiber is a transmission medium made of glass or plastic that is used to transmit light signals from one place to another. Based on the transmission mode used, optical fibers consist of Multimode Step Index, Multimode Graded Index, and Singlemode Step Index.
By using optical fiber is cheaper, slimmer shape, greater transmission capacity, less signal loss, data is converted into light signals so that it is faster. But the disadvantages include the high cost for the equipment, requiring the conversion of electrical data to light and vice versa which is complicated, requires special equipment in the procedure for use and installation, and for complex repairs requires skilled personnel in this field.
4. Unguided Transmission Media
In other words, the unsupervised transmission medium is a network that uses a wave system. Usually using microwaves (microwave), where microwaves are a form of radio waves that operate at high frequencies (in gigahertz units), which include the UHF, SHF and EHF areas. Microwaves are widely used in MAN network systems, internet cafes and internet service providers (ISP).
The advantage of using microwaves is that the acquisition between towers is not really necessary, can carry large amounts of data, low cost because each antenna tower does not require a large area, high frequency or short waves because it only requires a small antenna. While the weakness is that it is vulnerable to weather such as rain and is easily affected by aircraft passing over it.
5. Satellite
Satellite is a transmission medium whose main function is to receive signals from earth stations and forward them to other earth stations. Satellites orbiting at an altitude of 36,000 km above the earth have the same angular orbital velocity as the velocity orbital of the earth. By placing three geostationary satellites in the right position, it can reach the entire surface of the earth.
The advantage of this satellite is that it is cheaper than deploying a cable between continents, it can cover a large area of the earth, including remote areas with low populations. While the drawbacks are technological limitations for the use of a large size satellite antenna, investment costs and satellite insurance which are still expensive, large atmospheric losses for frequencies above 30 GHz limit the use of frequency carriers.
6. Infrared
Infrared is commonly used for short distance communication, with a speed of 4 Mbps. In its use for remote control, for example, remote control on televisions and other electronic devices. The advantage of infrared is that it is immune to radio and electromagnetic interference,