Qual é a diferença entre sinais analógicos e sinais digitais?
: 5363
: 2024-02-29 15:02:25
The difference between analog power amplifiers and digital power amplifiers is that the analog power amplifier inputs analog signals, while the digital power amplifier inputs digital signals converted from analog signals into digital signals. But many people are still confused about the concepts of "analog" and "digital", so let's talk about it today. “Analog and digital”. They are both signal modes and transmission methods. Especially in the audio and video industry, everyone must be familiar with analog interfaces and digital interfaces, so What is the difference between analog and digital? Strictly speaking, the various physical quantities we come into contact with in nature are analog signals, such as the sound of speech, temperature, humidity, light, etc. These data can continuously change over time. Taking a thermometer as an example, we can use time and temperature as coordinates to draw a continuous curve. This is the function image of the analog signal. |
During the transmission process, we can use sensors to convert various continuous signals into almost identical electrical signals. For example, rely on a microphone to simulate the sound wave signal at the vibration frequency of the vocal cords into an electrical signal. At this time, the waveform of the electrical signal is consistent with the original sound wave waveform. The speaking voice was recorded in this way. |
Early equipment recorded analog signals, such as film, tapes, telephones, surveillance cameras, etc. Analog signals are closest to the original form of nature and are indispensable in many fields. However, with the advent of the digital age, analog signals have also shown flaws. The biggest problem is weak anti-interference ability. After multiple transmissions or storage, the quality will also be lost. Therefore, the analog signal is more suitable for computer equipment. digital signal. |
If analog signals are simulations of natural forms, then digital signals are the "simulation" of analog signals. It samples the continuous curve of analog signals and turns them into discrete signals, and then quantifies these signals into specific values. Finally, it is expressed in binary form. |
After the analog-to-digital conversion process, each change in the signal has a corresponding specific value. No matter how many times it is copied or transmitted, signal loss can be greatly avoided as long as it corresponds to the original value. But you must also be able to see that digital signals are "distorted" during the recording process. Just like the image below, it is always different from the original image. For example, sometimes when we listen to music, we will feel an obvious "digital flavor", which is also a manifestation of "distortion". |
However, with the improvement of equipment performance, today's digital signals can divide the samples very finely, and with further processing, the final form is almost indistinguishable from analog signals. This is especially obvious in the video field. Today's cameras The images captured by other equipment are all digital, which can reach very high resolution, and can be easily processed on the computer and uploaded to various platforms.
But analog signals are not useless. From sensors to signal processing, the data collected in actual engineering applications are all analog signals. It can be said that analog signals are the basis of digital signals, and digital signals are the quantification of analog signals. Both There is no distinction between superior and inferior, just different ways of expression.
|