Patent ID: 7042869

Claim:
An apparatus in a communication system comprising: a receiver to receive a plurality of data units of a data packet, the receiver being configured to determine whether a preamble in a first data unit of the packet matches a preamble assigned to the apparatus; a transmitter operative to transmit ACK/NAK (acknowledgement/negative acknowledgement) information on an ACK/NAK channel for every received data unit, the transmitter comprising: a multiplier to cover the ACK/NAK information with a code to define the ACK/NAK channel; a spreader operative to spread the covered ACK/NAK information; and a channel gate for gating said ACK/NAK channel based on whether the receiver detected a matching preamble in the first data unit received by said receiver, the channel gate being configured to prevent transmission of the ACK/NAK channel for all data units of the packet when the receiver determines the preamble in the first data unit does not match the preamble assigned to the apparatus.