Trigger frame format for orthogonal frequency division multiple access (OFDMA) communication

An access point for communicating in a wireless communication network, the access point comprising:

• a network interface device having one or more integrated circuits (ICs) configured to:
• generate one or more trigger frames to trigger an uplink multi-user (MU) transmission by multiple client stations, wherein each of the one or more trigger frames includes a medium access control (MAC) header portion and a MAC frame body portion, wherein the MAC frame body portion includes (i) a common information field that includes information to indicate common transmission parameters to be used by the multiple client stations for the uplink MU transmission, and (ii) one or more per-station information fields that include respective information to indicate respective transmission parameters to be used by one or more respective client stations for the uplink MU transmission, and
• for each of the one or more trigger frames:
• generate the common information field to include (i) a subfield that indicates a bandwidth of the uplink MU transmission, and (ii) information that indicates a guard interval and a long training field (LTF) mode to be used by the multiple client stations for the uplink MU transmission, and
• generate each per-station field to include respective frequency allocation information that indicates respective frequency resources to be used by the respective client station for the uplink MU transmission;
• wherein the one or more ICs are further configured to:
• transmit the one or more trigger frames to the multiple client stations, and
• receive the triggered uplink MU transmission, wherein the triggered uplink MU transmission includes respective simultaneous transmissions from the multiple client stations.