Patent ID: 7986627

Claim:
A method, comprising: generating control messages that are respectively destined for two or more users; spreading each control message using a spreading code that is respectively associated with one of the users; summing the spread control messages, thereby to form a composite control message; in an OFDM transmitter in which a full range of subcarriers spanning an OFDM symbol is partitioned into a first plurality of subcarriers and a second plurality of subcarriers, mapping the composite control message to the first plurality of subcarriers, thereby to partially define one or more OFDM symbols, wherein the first plurality of subcarriers constitutes a common subchannel for signaling to the users; in the OFDM transmitter, mapping one or more further messages to the second plurality of subcarriers, thereby to fully define the one or more OFDM symbols; and transmitting the OFDM symbol or symbols.