Tag: Telecommunication
-
Microwave Passive Components: Types & Functions
The part of the electromagnetic spectrum referred to as the microwave region loosely includes 1-300 GHz for practical purposes. These microwave bands are especially advantageous for transmission services such as satellite transmission, telephone transmission, broadcasting of commercial radio & television, and oil platform transmission. Some of the key advantages of microwaves are that the energy…
-
Phase-Locked Loops (PLL) – Features, Operation & Applications
Features of a Phase-Locked Loop (PLL) A phase-locked loop (PLL) is a form of a servo system which consists of a phase detector, low-pass filter and voltage controlled-oscillator (VCO) as illustrated in the block diagram below. The phase detector compares the phase of the VCO with the incoming reference signal, giving an output proportional to…
-
Diode & Filter Applications in Amplitude Modulation (AM) Detection Circuits
The operation of a typical AM audio frequency signal is illustrated in the Figure 1.0 where vin is the modulated signal that is shown Figure 1.1. A typical amplitude modulated signal that is fed into the detector circuit: The diode removes the lower envelope and the upper envelope is illustrated below: The capacitor C2 and…
-
How Cellular Communication Systems Works
In cellular communication systems, there is a two-way wireless transmission between the cellular phone handset and the base station tower. The cell phone converts the audio signals into electrical form using a microphone. This information is imposed on a high frequency carrier signal by the process of modulation. The modulated carrier is radiated into free…
-
What is the difference between Broadband and Baseband Transmission?
Broadband transmission is used for a network in which information is modulated onto a radio frequency carrier which passes through the transmission medium such as a coaxial cable. Broadband transmission allows a number of modulated radio frequency carriers to be simultaneously transmitted and therefore offers a multichannel capability. Normally the topology of broadband LANs is…
-
General Principles of Radio Broadcasting, Transmission and Reception
Radio communication is the radiation of radio waves by the transmitting station, the propagation of these waves through the space and their reception by the radio receiver. The figure above shows the general principles of radio broadcasting, transmission and reception. We can divide the entire arrangement into 3 major sections, namely: Transmitter This equipment is…
-
Introduction to Radio Broadcasting, Transmission and Reception
In radio transmission, it is necessary to send audio signal e.g. music, speech, etc. from a broadcasting station over great distances to a receiver. This communication of audio signal does not employ any wire and is sometimes called wireless. The audio signal cannot be sent directly over the air for appreciable distance. Even if we…