What is radio frequency?

Radio frequency is referred to as RF. Radio frequency is radio frequency current, which is an abbreviation for a high-frequency alternating electromagnetic wave. An alternating current that changes less than 1,000 times per second is called a low-frequency current, and more than 10,000 times is called a high-frequency current, and radio frequency is such a high-frequency current. The cable television system uses radio frequency transmission.

In the theory of electronics, a current flows through a conductor and a magnetic field is formed around the conductor; an alternating current passes through the conductor and an alternating electromagnetic field is formed around the conductor, called electromagnetic waves.

When the frequency of the electromagnetic wave is lower than 100khz, the electromagnetic wave will be absorbed by the surface and cannot form an effective transmission. , We turn high-frequency electromagnetic waves with long-distance transmission capability into radio frequency, English abbreviation: RF

The electrical information source (analog or digital) is modulated with high-frequency current (amplitude modulation or frequency modulation) to form a radio frequency signal, which is transmitted into the air through the antenna; after the radio frequency signal is received at a long distance, it is inversely modulated to restore the electrical information source. This process is called wireless transmission.

Wireless transmission has developed for nearly two hundred years, forming a large number of users and product groups. However, due to the impact of climate change and surface obstacles, it is impossible to transmit perfect information.

Modern humans have invented cheap high-frequency transmission cables (radio frequency lines). In order to pursue the perfect information transmission quality and take into account the original wireless equipment, wireless wired transmission has become popular. The concept of radio frequency transmission was born.

If your information source undergoes secondary modulation and is transmitted to the opposite end with a cable, the opposite end uses inverse modulation to restore the information source before applying it. No matter how low the frequency is, it is also a radio frequency transmission method. If there is no modulation inverse modulation process, just The information source is transmitted to the opposite end directly by cable, no matter how high the frequency is, it is a general wired transmission method.