Wireless FAQ -> What is a radio system and different types of radio system?

What is a radio system?

The term radio system has many meanings depending upon the context in which it is used. However, all radio systems are on of three types: simplex, duplex or full duplex. The particular application that a designer is trying to solve dictates the type of system that will be used and the available options.

What is a simplex radio system?

In a simplex radio system, both radio links operate on the same frequency for transmitting and receiving the information. This system is typically used for point-to-point communication equipment such as walkie-talkies. The system is very basic and relies on only one party in the communication link transmitting at any time. There can be multiple users on this type of system.

What is a duplex radio system?

In a duplex radio system, both radio links use two separate frequencies for transmitting and receiving. Thus, in a duplex environment, unit 1 would send information to unit 2 on frequency F1 while unit 2 would send information to unit 1 on frequency F2.

The chief difference between half and full duplex systems is how the information between the two units is transferred. For example, in a full-duplex system, both unit 1 and unit 2 can be sending and receiving information at the same time without impeding each other. In contrast, in a half-duplex system, the operation is similar to that of a simplex system with the primary difference being that two discrete frequencies are used instead of just one.