What is signal?
A signal is a physical quantity containing information or data that can be transmitted over long distances and separated the information. In electronics/telecommunications, a signal is an electrical or electromagnetic current used to transfer data from one system or network to another. In this field we have 2 types of signals including Analog (analog) and Digital (digital).
Most signals in use today are in the form of functions, or processes that vary randomly with time or location. You can also understand the main signal as the variation of amplitude (usually voltage) over time. Signals can be generated by an electronic circuit and then transmitted in a circuit or communication medium. Sometimes the signal is converted by a sensor or signal converter into an electrical signal. For example, if you hold a microphone to sing, the mic will convert vibrations in the air into an audio signal; or you shoot movies, take pictures, the sensor in the camera will convert the light and color of the scene into color image signals.
Analog Signal
An analog signal (or analog signal) is a continuous signal that represents physical measurements, usually graphed as a continuous line (sine function), where a quantity varies with time. represents another quantity based on time. Called an analog signal, it does not mean that it is exactly the same, it is only similar in terms of signal nature, while the intensity will have a change. In everyday life, analog signals work with physical values and natural phenomena such as earthquakes, frequencies, volcanoes, wind speed, weight, light, sound, current or electric waves…
Advantages of Analog Signals
- Easy handling, mainly used to transmit information over long distances
- Suitable for audio and video transmission
- The system is cumbersome but simple, so investment and repair costs are cheaper
- Analog sound with high resolution should present full and rich information, meeting the enjoyment needs of people with golden ears.
- Consumes less bandwidth than digital signal
- More accurate sound reproduction
- Is the natural signal form of sound
- Mainly applied in the field of television, satellite, mobile network, fiber optic cable
Disadvantages of Analog Signals
- Signal quality is often lower than digital, susceptible to noise due to many factors
- Transmission cables are easily affected by the environment
- The cost of high-quality conductors is very expensive
- The editing is quite limited
- If the storage device (tape, disc) is damaged, it is quite expensive to record analog audio
- Data is perishable and the quality of the recording is very difficult to match the original, the more you copy, the worse the quality
Digital Signal
In contrast to Analog, a Digital signal (digital, discontinuous) is a discrete form of signal, at any given time it can only represent one of two values ”0″ or “1”, respectively. with binary language that computers can understand. Digital signals are not real outside of the natural environment but are created by technology. People record and convert Analog to Digital signals using electronic equipment, convert them into binary bits, and then store them on computers or other devices. The sound quality depends on the sampling rate, the part of data in 1 second is hashed into small chunks, the smaller (corresponding to a high hash rate), the higher the file quality will be, and the larger the file size will be. also heavier.
Advantages of Digital Signals
- Digital data can be compressed to save space easily
- Information in digital form can be encrypted for security
- Currently, devices that use digital signals are very popular and cheap
- Easily edit without changing the quality of the original
- Easily transmit and share over the network
- Always correct (because there are only 0 and 1) so avoid the error case
Disadvantages of Digital Signals
- The recording, recording of Analog signals to Digital will more or less lose information depending on the hash frequency
- Need large bandwidth and complex processing system, expensive investment cost
- Can be complained about the bad sound quality when enjoyed by golden ears
- Mixed signal hardware is required if you want to listen to or process Analog/Digital signals or vice versa
Thanks for reading!
