A two-way radio is simply a radio that can both transmit and receive (a transceiver). In broader terms, most of voice wireless communications systems, including cellular systems, fall into two-way radio definition.
Portable two-way radios are often called walkie-talkies or handie-talkies. Two-way radios are also available in mobile (installed in a vehicle) and base (in your office) configurations as well as utilizing radio network infrastructure.
A two-way radio is typically equipped with a “Push-To-Talk” PTT button to activate the transmitter. User just simply presses the PTT button and can immediately start to talk. User releases the PTT button to listen to others.
Two-way radio can “talk” directly to other radios or use radio network infrastructure. A direct talk among radios (usually also known as direct operation or talk around mode) has limited range due to limitation of radio power. To overcome this limitation, a radio repeater can be utilized to extend communication range.
With various wireless technology options and two way radio being one of the “earliest” wireless technologies, you might be questioning whether two-way radio is still a current technology. The answer is yes and the following are the key points that uniquely differentiate two-way radio to other wireless technology:
Two-way radio provides instant communication. The user only needs to press the “Push-To-Talk” (PTT) button and within fraction of a second, this user can immediately talk to convey his/her messages.
This is due to a quick call setup time embedded in the technology. This instantaneous communication capability is one of key factors of why many organizations rely on two-way radio for their tactical or operational communications.
(Conventional) Analog systems communicate a single condition. Information is sent by changing the frequency, amplitude or phase of the radio signal.
Digital systems, communicate text from computer-aided dispatch (CAD). Information is converted to true data bits, and applied directly to the radio transmitter using FDMA or TDMA or voice.