We can deliver a signal over a bandpass frequency range via modulation. If each signal has its own frequency range, we can send numerous signals utilizing distinct frequency ranges across a single channel at the same time. Another rationale for signal modulation is to enable the use of a smaller antenna. Modulation also enables us to transmit more information over a given channel.
In electronics, modulation is the process of encoding information into an analog signal that can be transmitted over a distance, then decoding the signal back into digital data when it reaches its destination. The act of encoding information into an analog signal is called modulation. The act of decoding encoded information back into its original form is called demodulation.
There are many different types of modulation techniques used in various applications requiring different properties from the modulated signal. For example, audio signals are most efficiently modulated using AM (amplitude modulation) because it uses little power and can be detected even if other signals are interfering with it. On the other hand, radio signals must carry multiple messages simultaneously and therefore require a method for distinguishing one message from another. This is done by modulating the signal with the unique identifications of the messages, which is called coding. Codes can be as simple as changing the amplitude of the signal at certain points or using symbols representing letters of the alphabet. Coded signals are then decoded by the receiver who reads the message based on how the codes were modified from their original value.
Communication benefits from modulation in a variety of ways. It enables us to send a signal over a specific frequency range known as the channel's bandwidth. The modulated signals are not interfering with one another. The bigger the antenna required to transmit a signal, the lower the frequency of that signal. For example, radio waves travel greater distances at higher frequencies than at low frequencies. This is why wireless internet connections using 5 GHz spectrum can cover much farther than 2.4 GHz networks.
The ability of modulation to convey information efficiently is called its coding gain. This means that you can send more information through a channel by modulating it than without modulation. For example, binary 10000000 vs unmodulated wave... yup, nothing special about that example! Binary data is the most common form of digital information and it requires two values to represent each digit: 0 and 1. Modulation allows these binary digits to be transmitted over a physical channel (such as an electrical conductor or spacewave) in order to reach another party.
In addition to enabling us to send more information over a channel, modulation also makes it possible to communicate messages that would otherwise be impossible to receive due to noise pollution. Noise tends to corrupt or interfere with the message itself, as well as the way it is modulated - causing reception problems for other receivers on the network. But by adding redundancy to our signals, we can overcome this problem.
Modulation is the process of encoding information from a message source so that it may be sent. Video, speech, and other data can be communicated by superimposing a message over a high-frequency signal known as a carrier wave (or sinusoidal signal). The message carrier signal must be modulated in some way to encode it for transmission through a medium such as air. At the receiving end, the carrier signal must be recovered before the original message can be decoded.
Modulation involves varying one or more characteristics of a carrier signal in accordance with an input message signal. The input message signal can be digital or analog; it can be continuous or discontinuous; and it can represent any kind of information, including images, audio, video, text, or data.
Carrier signals are commonly referred to as "waves" or "signals". They can take many forms, such as a light beam, radio frequency (RF) wave, or voltage pulse. A carrier signal does not itself carry information; it only carries a message when it is modulated by an input signal.
When modulating a carrier signal, it is important to understand that both the amplitude and the phase of the carrier signal must be varied in order to transmit information. Amplitude modulation (AM) varies the height of the wave, whereas phase modulation (PM) varies its angle relative to horizontal.