Retransmissions of NAK'd frames takes place utilizing a retransmission channel (103-105). In particular, NAK'd frames are retransmitted to requesting remote units (113-115) on a channel (103-105) differing from the channel (109) in which they were originally broadcast to the remote units (113-115). Because retransmission of poorly-received frames occurs utilizing a channel that differs from the downlink multicast channel, the downlink transmission rate of the downlink channel is not reduced when retransmission needs to take place. This greatly improves data transmission to those units not requesting retransmission of data.