Modulation is any of several means of encoding an information carrying signal onto a carrier of fixed frequency. The purpose is to allow the information to be transported long distances.
angle modulation is called non linear modulation because the information is stored in phase of the carrier signal
FM means Frequency Modulated.FM stands for modulation on frequency or frequency modulation.
Edwin Howard Armstrong is the inventor of modern frequency modulation
There are 3 main types of digital pulse modulation:Pulse time modulation (PTM), somewhat similar to analog phase modulation.Pulse width modulation (PWM), the width of the pulse represents the signal.Pulse code modulation (PCM), serial transmission of binary bits forming numeric or character codes that represent the signal.All of these can be modulated on an RF carrier using any of the standard modulation techniques: AM, FM, Phase Modulation, etc. One advantage with AM digital pulse modulation techniques over AM analog is that the carrier can be 100% modulated, which cannot be done with analog, thereby allowing significant reductions in transmitter power without loss of coverage range. Sometimes FM digital pulse modulation techniques are referred to as Frequency Shift Keying (FSK). A very complex method of combining Phase Modulation and AM to increase the bit density of digital pulse modulation on an RF carrier is called Quadrature Amplitude Modulation (QAM).
nonlinear device modulation is a process which imparts to sinusoidal two or more amplitude levels.
AM - Amplitude Modulation FM - Frequency Modulation
modulation
Frequency Modulation and Phase Modulation
frequency modulation..
due to velocity modulation density modulation occurs in TWT
The difference between frequency modulation and phase modulation is that with frequency modulation the angular frequency of the signal is modified while with the phase modulation, the phase angle of the signal is modified.
In Frequency Modulation (FM), if the modulation frequency is doubled, the modulation index does not necessarily double; it depends on the amplitude of the modulating signal. In Amplitude Modulation (AM), the modulation index is defined as the ratio of the peak amplitude of the modulating signal to the carrier amplitude, so it remains unchanged with varying modulation frequency. For Phase Modulation (PM), similar to FM, the modulation index is influenced by the amplitude of the modulating signal and does not inherently double with the modulation frequency. Thus, modulation frequency and modulation index are not directly linked in this way for FM, PM, or AM.
the modulation system is of FM
i dont know ans. of this.
QAM is a combination of phase modulation & amplitude modulation.
Frequency modulation Phase modulation
Modulation index is also called as Modulation depth. The modulation index of a modulation scheme describes by how much the modulated variable of the carrier signal varies around its unmodulated level.