Abstract: In a communication system for communicating on at least one channel group, a demodulator is disclosed. The channel group has at least one forward channel and at least one return channel, where a central station transmits data over the forward channel to a plurality of terminals at a forward data rate, and transmissions by each terminal to the central station are performed on any one of the return channels at a return data rate. The demodulator comprises a burst demodulator that demodulates received, discrete signaling packets of information over the return channels. The demodulator also comprises a message demodulator that is responsively connected to the burst demodulator, such that when the message demodulator is activated, the burst demodulator becomes deactivated when the return channel operates in a messaging mode. Thus, a feature of the demodulator is that it is a dual function demodulator that functions either as a burst demodulator, or as a continuous or message demodulator.