FreeDV is a graphical user interface (GUI) application for Mac that enables the use of any single sideband (SSB) radio for low bit rate digital voice communication. Speech is compressed to 1600 bits, then modulated onto a 16QPSK signal with a 1.25 kHz bandwidth, and transmitted to the microphone input of an SSB radio. On the receiving end, the signal is received by the SSB radio, demodulated and decoded by FreeDV.
