Radio signals are transmitted between a base station and mobile terminals. The radio signals are transmitted from the base station to the mobile terminals on a first frequency and are transmitted from the mobile terminals to the base station on a second frequency. The first frequency carries a downlink traffic channel, while the second frequency carries an uplink traffic channel. The first frequency further carries a first downlink signaling channel to a mobile terminal in the transmission phase on the uplink traffic channel, and a second downlink signaling channel to a mobile terminal in the reception phase on the downlink traffic channel. The second frequency further carries a first uplink signaling channel from a mobile terminal in the reception phase on the downlink logical traffic channel and a second uplink signaling channel from a mobile terminal in the transmission phase on the uplink traffic channel.