Tag: Radio Frequency (RF)
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Radio Frequency (RF) Signal Generator – Features & Applications
A radio frequency (RF) signal generator is used in generating high frequency signals at a specific frequency for testing laboratories. The output frequency may range for example from about 100 kHz to around 40 GHz. A typical RG generator consists of: RF oscillator, amplifier, output level meter and a calibrated attenuator. Components of RF Generator…
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Features of FM Receivers
FM receivers employ heterodyne principle. The FM broadcast signals lie in the frequency range between 88 MHz and 108 MHz. The intermediate frequency (IF) of a FM receiver is 10.7 MHz which is much higher than the IF value of 455 kHz in AM receivers. Let’s consider the block diagram of an FM receiver below:…
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Radio Frequency (RF) and Microwave – Multiple Choice Questions & Answers (MCQ3)
The Answers have been provided at the end of Questions. Q1. What is the approximate bandwidth of radio frequency (RF) electromagnetic waves? A. 300 Hz to 300 GHz B. 20 Hz to 20 kHz C. 300 Hz to 3000 GHz D. 300 MHz to 300 GHz Q2. In spectral analysis the following factors are considered…
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Demodulation in Telecommunication Systems
Demodulation is the process of recovering the audio signal from the modulated wave. Demodulation is also known as detection in communication systems. Why Demodulation is needed in Telecommunication Systems Amplitude modulated wave consists of carrier and sideband frequencies. The audio signal is contained in the sideband frequencies which are radio frequencies. If the modulated wave…
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Modulation in Communication Systems
Introduction Modulation is the process of changing some characteristics (e.g. Amplitude, Frequency, or Phase) of a carrier wave in accordance with the intensity of the message signal. Modulation means to ‘’change’’. In Modulation, some characteristics of the carrier wave is changed in accordance with the intensity i.e. amplitude of the message signal. The resultant wave…
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Radio Frequency (RF) and Microwave Spectral Analysis
The display of electromagnetic radiation as a function of wavelength is termed to as electromagnetic spectrum. Based upon the wavelengths, the spectrum is divided into various frequency bands as illustrated in the figure below: With the rapid advancement of wireless technology and satellite sensor technology, there is need for more and more accurate field measurements…
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The Basics Facts about Photons
Photons are the elemental units of electromagnetic spectrum. For example, white light is composed of a number of different kinds of photons, some are red photons, some are blue photons, etc. Note that, there is no white photon; instead the combination of the various colored photons when they interact with your eyes, your brain perceives…
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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 Transmission of radio…
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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…
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Components that make up a RF Communication System
Communication is the process of transferring information from one place to another. The information that is generated at the source is transferred to the receiver through communication channel. From the diagram above, on the source side, there is a transmitter device that makes the input electrical information suitable for efficient transmission over a given channel.…