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What is the difference between a carrier wave and an AM modulated wave?
The difference is in how the carrier wave is modulated, or altered. With AM radio, the amplitude, or overall strength, of the signal is varied to incorporate the sound information. With FM, the frequency (the number of times each second that the current changes direction) of the carrier signal is varied.
What is the power relationship between the carrier and the modulating signal in AM?
If the modulation index μ=1 then the power of AM wave is equal to 1.5 times the carrier power. So, the power required for transmitting an AM wave is 1.5 times the carrier power for a perfect modulation.
What does the mixing of an RF carrier and the modulation signal during amplitude modulation AM create?
When a carrier is modulated in any way, further signals are created either side of the steady carrier. These sidebands carry the actual modulation information. The process of modulating a carrier is exactly the same as mixing two signals together, and as a result both sum and difference frequencies are produced.
How does amplitude modulation affect the carrier wave?
The audio waveform modifies the amplitude of the carrier wave and determines the envelope of the waveform. In the frequency domain, amplitude modulation produces a signal with power concentrated at the carrier frequency and two adjacent sidebands.
Which is an example of a modulation signal?
For example, frequency modulation takes an RF “carrier” signal (sine wave) at say 88MHz and varies the frequency slightly, based on your “modulating” signal which will most likely be an audio signal up to 15kHz or so. Similarly, amplitude modulation may take a 1.6MHz carrier signal and vary the amplitude using an audio signal.
How is AM technique different from frequency and phase modulation?
The AM technique is totally different from frequency modulation and phase modulation where the frequency of the carrier signal is varied in the first case and in the second one the phase is varied respectively. There are three main types of amplitude modulation.
How is the carrier wave of an AM transmitter generated?
One of the crude pre-vacuum tube AM transmitters, a Telefunken arc transmitter from 1906. The carrier wave is generated by 6 electric arcs in the vertical tubes, connected to a tuned circuit. Modulation is done by the large carbon microphone (cone shape) in the antenna lead.