Method of adapting the air interface and mobile radio system and corresponding base transceiver station, mobile station and transmission mode

A mobile radio system including at least one mobile station and a network capable of exchanging digital signals bi-directionally between the at least one mobile station and the network, said system comprising:

• means for providing at least two coding modes, each coding mode corresponding to a predetermined source coding and a predetermined channel coding for transmission of a wanted signal for each transmission direction;
• and
• means in the mobile station for measuring, at the time of a call between the mobile station and the network, transmission quality in a downlink direction from said network to the mobile station, and for transmitting to said network information representative of the measured transmission quality in said downlink direction, and means in the network for measuring transmission quality in an uplink direction from the mobile station to said network;
• wherein the network comprises a mode control means for selecting, in accordance with the measured transmission quality in the uplink direction, one of the coding modes to be used in the uplink direction, for transmitting a change mode command to the mobile station if necessary, and for selecting, in accordance with received information representative of the measured transmission quality in the downlink direction, one of the coding modes to be used in the downlink direction.

A network equipment for a mobile radio system including at least one mobile station and a network capable of bi-directionally exchanging digital signals between the network and the at least one mobile station, the system providing at least two coding modes, each of said coding modes corresponding to a predetermined source coding and a predetermined channel coding for transmission of a wanted signal for each transmission direction, said network equipment comprising:

• means for determining a first indication representative of transmission quality in an uplink direction from the mobile station to the network;
• means for receiving a second indication representative of transmission quality in a downlink direction from the network to the mobile station;
• mode control means for modifying the one of said coding modes which is used in said each transmission direction on the basis of said first and second indications;
• and
• means for transmitting, to said mobile station, information representative of selected ones of said coding modes.

A mobile station of a mobile radio system including at least one mobile station and a network capable of bi-directionally exchanging digital signals between the network and the at least one mobile station, the system providing at least two coding modes, each coding mode corresponding to a predetermined source coding and a predetermined channel coding for the transmission of a wanted signal for each transmission direction, said mobile station comprising:

• means for determining an indication representative of transmission quality in a downlink direction from the network to the mobile station;
• means for transmitting said indication to said network;
• and
• means for receiving from said network an indication representative of coding modes selected by said network for each transmission direction.