Digital walkie-talkies use digital encryption to protect users' information. In some special industries, such as civil aviation and railways, the information security requirements are relatively competitive. There are many methods for encryption. For example, the digital signal and a long-term rice sequence can be modulo 2 added to complete the encryption. The receiving end uses the same meter sequence and the received encrypted signal to perform modulo-2 addition again, that is, the decryption is completed. .
Advanced governance protection organization
Analog walkie talkie
The analog walkie-talkie is an analog walkie-talkie (also known as a traditional walkie-talkie) designed with analog communication technology. It modulates the stored signal to the transmission frequency of the walkie-talkie.
Public walkie-talkies, commonly known as civilian walkie-talkies. There is no need to approve the use of the public walkie-talkie, no frequency occupancy fee, no call charges, anyone can purchase and use. However, such public walkie-talkies have clear regulations on frequency, power and technical indicators. As a public walkie-talkie, the technical specification stipulates that the programming operation function cannot be set on the front panel of the walkie-talkie. The purpose is to prevent the user from expanding the frequency range and modifying the work parameters. According to the regulations, the public walkie-talkie can only display the number of channels and cannot display its working frequency. At the same time, it is also stipulated that the public walkie-talkie can use sub-audio technology (CTCSS) below 300HZ, commonly known as anti-interference code or private line to prevent interference with the same frequency intercom.
Public network intercom
Supporting national intercom, there is no limit to the distance, and it can achieve interoperability across the country, and there is no limit to the distance. For example, one Harbin, one across the country in Sanya, Hainan, can implement clear, zero-delay interoperability. The operation is the same as that of a traditional walkie-talkie.