Wavelet modulation

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Wavelet modulation, also known as fractal modulation, is a modulation technique that makes use of wavelet transformations to represent the data being transmitted. One of the objectives of this type of modulation is to send data at multiple rates over a channel that is unknown. [1] If the channel is not clear for one specific bit rate, meaning that the signal will not be received, the signal can be sent at a different bit rate where the signal-to-noise ratio is higher.

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Modulation is defined as the process by which some characteristics like amplitude, frequency, and phase of a carrier signal are varied in accordance with a modulating wave.

<span class="mw-page-title-main">Orthogonal frequency-division multiplexing</span> Method of encoding digital data on multiple carrier frequencies

In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission used in digital modulation for encoding digital (binary) data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, used in applications such as digital television and audio broadcasting, DSL internet access, wireless networks, power line networks, and 4G/5G mobile communications.

Quadrature amplitude modulation (QAM) is the name of a family of digital modulation methods and a related family of analog modulation methods widely used in modern telecommunications to transmit information. It conveys two analog message signals, or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves, using the amplitude-shift keying (ASK) digital modulation scheme or amplitude modulation (AM) analog modulation scheme. The two carrier waves are of the same frequency and are out of phase with each other by 90°, a condition known as orthogonality or quadrature. The transmitted signal is created by adding the two carrier waves together. At the receiver, the two waves can be coherently separated (demodulated) because of their orthogonality. Another key property is that the modulations are low-frequency/low-bandwidth waveforms compared to the carrier frequency, which is known as the narrowband assumption.

In telecommunication and electronics, baud is a common unit of measurement of symbol rate, which is one of the components that determine the speed of communication over a data channel.

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<span class="mw-page-title-main">Delta modulation</span> Signal conversion technique

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<span class="mw-page-title-main">Line code</span> Pattern used within a communications system to represent digital data

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<span class="mw-page-title-main">Communication channel</span> Physical or logical connection used for transmission of information

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<i>E</i><sub>b</sub>/<i>N</i><sub>0</sub> Normalized signal-to-noise ratio measure

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Pulse-code modulation (PCM) is a method used to digitally represent analog signals. It is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. In a PCM stream, the amplitude of the analog signal is sampled at uniform intervals, and each sample is quantized to the nearest value within a range of digital steps.

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