Updated 20 Jan This file generates the amplitude modulated signal and DSBSC wave for given carrier wave frequency, message signal frequency and modulation Index. Nikhil Prathapani Retrieved June 5,
|Published (Last):||19 April 2011|
|PDF File Size:||19.66 Mb|
|ePub File Size:||17.77 Mb|
|Price:||Free* [*Free Regsitration Required]|
The equation of AM wave in its simplest form i. From this equation, it is obvious that the carrier component in AM wave remains constant in amplitude and frequency. This means that the carrier of amplitude modulated wave does not convey any information.
In power calculation of AM signal, it has been observed that for single-tone sinusoidal modulation, the ratio of the total power to the carrier power is :. The resulting signal obtained by supressing the carrier from the modulated wave is called Double sideband supressed carrier DSB-SC system.
A linear modulator is a system whose gain or transfer function can be varied with time by applying a time varying signal at certain points. Let us consider fig. AS an alternative we can use the carrier as gain varying signal and x t as the input signal as shown in fig 3.
The balanced modulators are used to suppress the unwanted carrier in AM wave. The carrier and modulating signals are applied to the inputs of the balanced modulator and we get the DSB signal with supressed carrier at the output of the balanced modulator.
Hence, the output consists of the upper and lower sidebands only. The principle of operation of a balanced modulator states that if two signals at different frequencies are passed through a non-linear resistance then at the output, we get an AM signal with suppressed carrier.
The device having a non-linear resistance can be a diode or a JFET or even a bipolar transistor. It consists of two standard amplitude modulators arranged in the balanced configuration so as to suppress the carrier completely. The R. I am Sasmita.
At ElectronicsPost. And, if you really want to know more about me, please visit my "About" Page. Read More. Sasmita Hi!
Analog Communication - DSBSC Modulators
Double-sideband suppressed-carrier transmission DSB-SC is transmission in which frequencies produced by amplitude modulation AM are symmetrically spaced above and below the carrier frequency and the carrier level is reduced to the lowest practical level, ideally being completely suppressed. DSB-SC transmission is a special case of double-sideband reduced carrier transmission. It is used for radio data systems. This mode is frequently used in Amateur radio voice communications, especially on High-Frequency bands. DSB-SC is generated by a mixer.
Select a Web Site
Double-sideband suppressed-carrier transmission