The data on a network is transmitted through in electrical signal cal carrier signal. The signal oscillates back and forth across a zero voltage line. The area above the line called positive voltage and the area below the line for negative voltage. That is why why we called it carrier wave or sine wave. Signal is an analogue signal as we already read that there are two types of signals analogue Signals and digital signals analogue signal means something continuous an example of analogue data is human voice. Whereas digital signal is a sequence of voltage represented in a binary form the digital signals are in the form of electrical pulses of ON and OFF. Aquarius signal is an analogue signal analogue signal is a continuous wave where as a digital signal consists of discrete elements. The analogue signal requires some method to convert it into digital data. The signal modulation is performed by a modem in many data communication networks.
There are three types of modulation
1. Amplitude modulation
Amplitude modulation is a change in the height of carrier wave. The height of the signal is changed to indicate 0 bit or 1 bit when data is sent on the carrier signal. The use peak in the Sine wave produce loudest sound and the lower peaks on the Sine wave produce smallest sound. Amplitude Modulation is a fun used for radio transmission bi a m radio stations. The factors that influence the a.m. Modulation are noise and interference from external sources.
2. Frequency modulation
Frequency modulation refers to the number of waves used to represent a single cycle. The change in frequency is indicated by a difference in the tone of the signal. Higher tone indicates more wave per unit of time and load Don indicates pure wave per unit of time. 1 bit represent higher pitch whereas 0 bit present low pitch. Frequency modulation is also called frequency shift keying. It is affected by external interference.
3. Phase modulation
It is also a type of signal modulation in which phase shift occurs to indicate a change in the type of Beats being transmitted. The phase or direction of the wave changes when it goes from zero to one bit are from 1 to 0 bit the Waves moves in a specific direction to indicate one bit or 0 bit. It is also called phase shift think and it is affected by external interference and noise.
There are three types of modulation
1. Amplitude modulation
Amplitude modulation is a change in the height of carrier wave. The height of the signal is changed to indicate 0 bit or 1 bit when data is sent on the carrier signal. The use peak in the Sine wave produce loudest sound and the lower peaks on the Sine wave produce smallest sound. Amplitude Modulation is a fun used for radio transmission bi a m radio stations. The factors that influence the a.m. Modulation are noise and interference from external sources.
2. Frequency modulation
Frequency modulation refers to the number of waves used to represent a single cycle. The change in frequency is indicated by a difference in the tone of the signal. Higher tone indicates more wave per unit of time and load Don indicates pure wave per unit of time. 1 bit represent higher pitch whereas 0 bit present low pitch. Frequency modulation is also called frequency shift keying. It is affected by external interference.
3. Phase modulation
It is also a type of signal modulation in which phase shift occurs to indicate a change in the type of Beats being transmitted. The phase or direction of the wave changes when it goes from zero to one bit are from 1 to 0 bit the Waves moves in a specific direction to indicate one bit or 0 bit. It is also called phase shift think and it is affected by external interference and noise.
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