Radio communication system for providing both voice and data communication services over radio communication channels and a method for use in a radio communication system

A computer program product, comprising:

• a computer readable medium;
• and
• computer program instructions recorded on the computer readable medium and executable by a processor for carrying out a method for use in a radio communication system comprising a system computer connected to a radio communication device comprising a radio communication antenna and an audio management system via a data bus, said audio management system being connected to a user communication device, the method comprising:
• receiving, from the radio communication device, a signal in said system computer indicating that a carrier on a fixed frequency has been detected by said radio communication device, or, from the audio management system, a signal in said system computer indicating that a request for a predetermined fixed frequency voice communication service has been detected by said audio management system;
• and
• switching to a voice communication service by said system computer in response to receiving one of said signals.