Patent ID: 8102801

Claim:
A user equipment, comprising: a higher layer automatic repeat request (ARQ) mechanism configured to generate data for transmission; a physical layer transmitter configured to receive the data for transmission from the higher layer ARQ mechanism, to format the received data into packets for transmission, the packets being smaller in size than the data blocks, appending an error check sequence for each packet, wherein the packets are transmitted using an orthogonal frequency division multiple access (OFDMA) air interface, the physical layer transmitter configured to retransmit an original or selectively modified packet, wherein the retransmitted original or selectively modified packets are combined with transmitted packets, if an acknowledgment for that packet has not been received within a predetermined period of time; a physical layer receiver configured to receive and demodulate received packets; an ACK transmitter configured to transmit a corresponding acknowledgment for a given packet, wherein a mechanism configured to receive the corresponding acknowledgment for the given packet operates transparently with respect to the higher layer ARQ mechanism; and an adaptive modulation and control (AMC) unit configured to adjust a particular encoding/data modulation of each packet using collected retransmission statistics; and wherein subchannels from an OFDM frequency set are selectively nulled based on a retransmission rate or the retransmission rate/link quality, wherein the use of a poor quality subchannel is precluded and on a condition that the retransmission rate or the retransmission rate/link quality indicates a high quality for the previously nulled subchannel, adding a previously nulled subchannel back into the OFDM frequency set.