Amplitude Modulation

Communication Systems are the systems used to transfer quality information from one point to another through various components. A technique called modulation is most common in communication systems for telecommunications. I like to share this Electric Circuit Simulator with you all through my article.

This is done by a component called modulator and is present at transmitter’s end. Opposite working component of the same is demodulator which is present at receiver’s end and performs reverse of the same.
It is a method or technique of changing a property of high frequency carrier wave in accordance to the modulating signal. Any of the one of the following properties is changed: amplitude, frequency and phase of the carrier wave. So, it is used to transfer an information signal (modulating signal) inside another signal (carrier wave).

Amplitude form of adding information signal is a technique of varying amplitude of the carrier wave according to the instantaneous amplitude of the modulating signal. For example if the instantaneous amplitude of modulating signal is positive then the amplitude of carrier wave will be increased while if the amplitude of modulating signal is negative then the amplitude of the carrier wave will be decreased.
advantages of amplitude modulation is that long distance propagation is possible through it. Also amplitude form is cheaper and less complex. The coverage area of AM receivers is large.
Let us understand what is frequency modulation now: This is another technique of analog modulation in which instantaneous frequency of carrier wave is varied according to the instantaneous values of modulating signal (which carries information).  This technique is mostly used in music and voice broadcasting, radio systems, video transmissions etc.

Is this topic Friction Equation hard for you? Watch out for my coming posts.

digital frequency modulation is a technique used for transmission of digital signal or digital stream . This is done by shifting the frequency of carrier wave among a range through a technique called frequency shift keying. The digital information is transferred by discrete frequency changes in carrier. The simplest technique of frequency shift keying is binary shift keying. In this technique binary information is transferred using a couple of discrete frequency. Binary information is in the form of 0 and 1. Here 1 is called mark frequency and 0 is called space information.

pulse width modulation definition : it is a technique of changing the digital signal into pulses to simulate a change in voltage. Terms used in PWM: period: time taken to complete pulse cycle. Frequency: number of pulses generated in a unit time and duty cycle: time in a period for which pulses are high. The technique uses rectangular pulses whose width is modulated such that average value of waveform varies.