What is ASK (Amplitude Shift Keying)?
Amplitude shift keying, also known as "amplitude shift keying", is a modulation technique. If the possible states of a digitally modulated signal correspond one-to-one to binary information symbols or their corresponding baseband signal states, the modulated signal is called a binary digitally modulated signal. Typing using binary information symbols is called binary amplitude keying and is represented by 2ASK.
In "shift keying" mode, when a "1" appears, the carrier with amplitude A is turned on, and when a "0" appears, the carrier is turned off. This is equivalent to shifting the original baseband signal (pulse train) spectrum to two carriers. Amplitude Shift Keying (ASK) is equivalent to amplitude modulation in an analog signal, except that it is a binary number multiplied by the carrier frequency signal. Amplitude offset is the transmission of information bits through the amplitude of the carrier using frequency and phase Single serial port server as constants and amplitude as a variable. Binary Amplitude Keying (2ASK), since the modulating signal has only two levels of 0 or 1, the result of the multiplication is equivalent to turning off or turning on the carrier frequency. Its actual meaning is that when the modulated digital signal is "1", the carrier is transmitted; when the modulated digital signal is "0", the carrier is not transmitted. Usually, the carrier signal uses a cosine signal, and the modulating signal converts the digital sequence into a unipolar baseband rectangular pulse sequence. The function of on-off keying is to multiply the output and the carrier, and move the spectrum to the vicinity of the carrier frequency, realizing 2ASK.
The simplest and most commonly used form of amplitude shift keying modulation technique is switching. The presence of the carrier is indicated by "1" and the absence of the carrier is indicated by "0". This type of modulation is called on-off keying (OOK), AC-DC dual and it is the most energy-efficient modulation method because it radiates energy only when a "1" is sent. Amplitude shift keying requires a very high signal-to-noise ratio to demodulate the signal, because by its own characteristics, most signals are transmitted with very low power. The advantage of ASK modulated RF systems is the structure of transmit and receive.