channel for the corresponding downlink packet to the base station b the base station b receives the uplink ack nack channel and provides the corresponding contents to the base station a as another example the base station a transmits the allocation information regarding the uplink packet to the terminal and also provides the same to the base station b accordingly the base station b can receive the uplink packet from the terminal the base station b receiving the uplink packet transmits the received packet and or ack nack information to the base station a the base station a transmits the received ack nack information to the terminal through the downlink ack nack channel fig3 shows an embodiment of a proposed data transmission method fig3 represents a case of handed over to the other base station for only uplink transmission in a state where the terminal has performed the network entry to one base station referring to fig3 the terminal is in a network entry to the base station a at step s 100 and hands over to the base station b at the uplink transmission at step s 110 to the base station b in other words the terminal connects only the uplink to the base station b in the state where the downlink is connected with the base station a in succession the uplink handover of the terminal may be performed according to the need of the.