Found 1627 Articles for Computer Network

It makes use of the lower gigahertz frequencies of the electromagnetic spectrum. These frequencies are higher than radio frequencies, and they make better throughput and execution. This transmission can be further classified as Terrestrial or Satellite.Types of Microwave TransmissionThere are two types of microwave transmission, which are as follows.Terrestrial Microwave TransmissionThese systems use directional parabolic antennas to transmit and receive signals in the lower gigahertz range, as shown in the figure. These signals are highly focussed and travel insight. Relay towers can extend signals. Smaller terrestrial microwaves systems can be used inside a building. Some microwave LANS works at low ... Read More

The electromagnetic waves having frequencies between 1 and 300 GHz are known as a microwave. Microwave systems use very high-frequency radio or television signals to transmit data through space. Therefore, the transmitter and receiver of a microwaves system, which is mounted on very high towers, should be invisible to each other, i.e., they both should be in a line-of-sight. Moreover, the signals become weak after travelling a certain distance and require power amplification.Microwave systems can carry large quantities of data at high rates of speed. The data transmission rate is about 16 gps (Gigabits per second). A microwave system can ... Read More

Radio waves have frequencies between 10 kHz and 1 gigahertz. The range of electromagnetic spectrum between 10 kHz and 1 GHz is known as radiofrequency (RF).Radio waves are omnidirectional. When an antenna sends radio waves, they are propagated in all directions. This defines that the sending and receiving antennas do not have to be aligned.A sending antenna sends waves that any receiving antenna can receive. It is based on the wavelength, strength, and purpose of transmission. There are various types of antennas, as display in the figure.Radio waves are those waves that propagate in the sky mode, can travel long ... Read More

In this type of media, the signal propagates in the form of electromagnetic waves without the requirement of solid media, i.e., in the air. There are also called wireless media.The electromagnetic spectrum used for wireless communication is shown in the figure −Propagation MethodsThe unguided signals can travel from the transmitter to the receiver in many different ways. The three most important methods are −Ground Wave PropagationSKY PropagationSpace propagation or line of sight propagationBandsThe electromagnetic spectrum is divided into several subbands. The following table shows various frequency bands corresponding to multiple types of propagation and application −Electromagnetic Waves BandNameFrequencyWavelengthExtremely Low Frequency ... Read More

We are getting different types of services by using various modes of communication. The wired method of communication is one of the most efficient and successful modes. There are different types of cables available such as twisted pair cables, coaxial cables, and optical fiber cables. Read through this article to find out the characteristic features that differentiate these cables. What is a Twisted Pair Cable? A twisted pair cable comprises two insulated wires that have been twisted together. They are in use in the field of communications for a long time. You might have seen this type of cable ... Read More

A fibre optic cable is made of glass or plastic and transmits signals in the structure of light signals. The structure of an optical fibre cable is displayed in the figure. It involves an inner glass core surrounded by a glass cladding that reflects the light into the core. Each fibre is encircled by a plastic jacket.In fibre optics, semiconductor lasers transmit data in the form of light along with hair-thin glass (optical) fibres at the speed of light (186, 000 miles second) with no significant loss of intensity over very long distances. The system includes fibre optic cables that ... Read More

Co-axial includes a central copper wire surrounded by PVC insulation over which a copper mesh sleeve is placed. Again, the metal sleeve is shielded by an outer shield of thick PVC material, as shown in the figure.The coaxial cable structure provides it with the right mixture of high bandwidth and good noise community. For 1 km cables, a data price of 10 Mbps is feasible. Higher data rates are applicable for shorter cables. Co-axial cables are generally used for cable TV and long-distance transmission within the telephone system.Characteristics of Co-axial CableThe main characteristics of the coaxial cable are as follows ... Read More

Twisted-pair are generally made of copper, and a pair of wires are twisted together to decrease interference by adjacent wires. A twisted pair includes two conductors (copper), each with its plastic insulation, twisted together. One of the wires can transfer signals to the receiver, and the difference is used just as a ground reference. The receiver helps the difference between the two.This means, if two wires are correlated to each other, the noise or crosstalk can affect one wire, and the difference between the two levels would vary. When these wires are twisted, both wires have a similar effect of ... Read More

A transmission media can be represented as anything that can take data from a source to a destination. The transmission media function maintains the data in the form of bits through LAN (Local Area Network).In data communications, the definition of the data and the transmission medium is more precise. The transmission medium is generally free space (i.e., air), metallic cable or fiber-optic cable. The data is frequently a signal that is the result of a conversion of data from another form.Causes of Transmission ImpairmentNoise absorption is due to susceptibility leading to external electrical noise, distorting the data signal and data ... Read More

It is the description of analog data by an analog signal. Modulation of analog signals means converting analog signals to an analog signal. It is required because the sender’s signal is of low pass and can be of the same range. For example, each radio station has a low pass signal, which may be of the same range. Different stations signal to avoid intermixing; each low pass signal must be shifted to a diverse range on the frequency band.The diagram shows the relationship between the analog information, the analog-to-analog conversion hardware, and the resultant analog signal.Analog-to-Analog modulation can be achieved ... Read More