Carrier signal is of high frequencies, it gives strength to the original signal because original signal cannot travel long distances so it needs to be strengthen a bit for transmitting.
The carrier signal is a high frequency signal, called an RF. Radio Frequency signal, it is to high for the human or animal ear to detect it, so its outside the audible spectrum and can easily be transmitted over the air to receivers that is tuned to receive that frequency and detect any modulation on that signal.
modulation means transmitting the signal which is to be transmitted along with the carrier wave, then at the receiver it is separated from the carrier and demodulated. So modulation is needed so as to transmit the signal over long distances with higher accuracy. Hence it is required before multiplexing.
To avoiding the noise signal effect.Because the modulation is a technic which providing a high characteristic to transmitting the signal on long or short distance.Because the modulated signal received as high bandwidth,high performance of received signal and the modulation Technic is provide a less hight of antenna in wireless transmission which is expressed in the term :(hight of antenna=λ/4).
Modulation in radio broadcasting is important because it is necessary to adjust the carrier signal so that the information in the modulating signal can be broadcasted. You must have modulation in order to transmit thru a radio wave.
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.
Carrier Wave: A carrier wave is a high-frequency electromagnetic wave that is used as the "carrier" or the base signal in a modulation process. It is typically a pure sine wave with a constant frequency and amplitude. The carrier wave by itself does not carry any information; it serves as a vehicle to carry the information from one location to another. In AM and FM radio broadcasting, the carrier wave is the primary signal transmitted by the radio station. Modulated Wave: A modulated wave is the result of combining the carrier wave with an information signal, such as an audio signal or data. Modulation is the process of varying the characteristics of the carrier wave (either its amplitude or frequency) in accordance with the information signal. There are two common types of modulation: Amplitude Modulation (AM) and Frequency Modulation (FM). In AM, the amplitude of the carrier wave is varied in proportion to the amplitude of the information signal. This variation encodes the information onto the carrier wave. In FM, the frequency of the carrier wave is varied in proportion to the amplitude of the information signal. This variation encodes the information onto the carrier wave. The modulated wave contains the information that needs to be transmitted, and it can be demodulated at the receiving end to retrieve the original information.
AM imply amplitude modulation of a carrier signal
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.
Amplitude of the (high frequency) Carrier signal is varied with respect to low frequency of message signal is called amplitude modulation. Frequency of the carrier signal is varied with respect to low frequency of message signal is called frequency modulation.
low level amplitude modulation occurs when the carrier signal is first modulated and then amplified,whereas in high level modulation,the carrier signal is first amplified and then is modulated.
A: A carrier carry information by modulation either Amplitude or Frequency modulation. Therefore AM and FM RADIO M stand for modulation
modulating signal is the message to be carried by the carrier signal.
amplitude modulation is where we modulate our signal with a carrier signal amplitude changes but frequency remains constant in amplitude modulation
Analog Modulation
FM stands for frequency modulation. The definition is: when the frequency of the carrier wave is changed in accordance with the intensity of the signal, it is called frequency modulation. In frequency modulation, only the frequency of the carrier wave is changed in accordance with the signal. However, the amplitude of the carrier wave remains unchanged.
Modulation is the addition of information to an electronic or optical signal carrier. The modulation can be applied by turning the signal on and off.
Frequency modulation and Phase modulation
The intelligence signal is in the AM envelope.In AM modulation, the carrier is amplitude modulated by the signal. This signal appears as the envelope of the carrier. You can demodulate it by following the peaks on each cycle of the carrier. You can either follow the positive peaks or the negative peaks - it does not matter if the original modulation is symmetrical.