Analog signals and digital signals

Analog signals are continuous and can take values at any point in time, usually reflecting the continuous changes in nature, such as sound, television images, etc; Digital signals are discrete and only take values at specific time points, typically in binary form. Analog signals lay the foundation for communication, while digital signals drive the development of smarter and faster communication.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

If analog signals are simulations of natural forms, then digital signals are simulations of analog signals. They sample the continuous curves of analog signals to become discrete signals, then quantify these signals into specific numerical values, and finally represent them in binary form. After the process of analog to digital conversion, each change in the signal has a corresponding specific value. No matter how many times it is copied or transmitted, as long as it corresponds to the original value, signal loss can be greatly avoided. For the conversion of analog signals into digital signals, the sampling process is to convert the signal values in continuous time into numerical values in discrete time. In theory, the higher the sampling rate, the higher the accuracy of digital signal reconstruction, but it also means that the amount of data generated by sampling is larger, and the time and cost required for storage and processing will increase.