Patent ID: 11871367
Assignee: AVAGO TECHNOLOGIES INTERNATIONAL SALES PTE. LIMITED
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 22:
23. A first access point comprising:
a transceiver; and
circuitry configured to:
cause the transceiver to receive, during a first time period, from a second access point, information for a joint transmission by the first access point and the second access point to a device,
estimate synchronization information for the joint transmission, according to the information for the joint transmission, and

cause the transceiver to transmit, during a second time period after the first time period, a portion of a null data packet to the device according to the synchronization information, while the second access point transmits the portion of the null data packet to the device during the second time period, the device to determine, according to the portion of the null data packet, steering information for a multiple-input multiple-output (MIMO) communication to determine steering vectors for the joint transmission by the first access point and the second access point to the device, wherein the circuitry is further configured to:
cause the transceiver to receive, during a third time period before the first time period, from the second access point, a trigger frame, and
estimate additional synchronization information for a null data packet announcement, according to the trigger frame, and
cause the transceiver to transmit, during a fourth time period between the third time period and the first time period, the null data packet announcement to the device according to the additional synchronization information, while the second access point transmits the null data packet announcement to the device during the fourth time period, the device to prepare for the null data packet, according to the null data packet announcement transmitted by the first access point and the second access point.