High speed data interface for land mobile communication system

A data interface unit for interfacing a data terminal or the like with a transceiver for a voice radio communications system, said transceiver including a detector presenting an unfiltered audio signal, said audio signal having a received clock encoded data signal modulated thereon, said interface unit being adapted for receiving said unfiltered audio signal from said transceiver and for coupling to said transceiver for modulation of signals within said transceiver with a transmitted clock encoded data signal, comprising:

• input means adapted for coupling to said transceiver detector for monitoring of said unfiltered audio signal, said input means including filter means for presenting said unfiltered audio signal as a bandwidth limited information signal;
• signal demodulator means operably coupled to said filter means for demodulating said bandwidth limited information signal to present said received clock encoded data signal;
• clock recovery means operably coupled to said signal demodulator means for recovering received clock information from said received clock encoded data signal;
• data demodulating means operably coupled to said signal demodulator means and said clock recovery means for recovering received data signals from said received clock encoded data signal;
• logic means operably coupling said data demodulating means with said data terminal for presentation of said received data signals to said data terminal and for receiving outgoing data signals from said data terminal;
• encoding means operably coupled to said logic means for encoding said outgoing data signals with timing information to present said transmitted clock encoded data signal;
• and
• coupling means operably coupled to said encoding means for presenting said transmitted clock encoded data signal to said transceiver.