US 12,335,204 B2
Wireless local area network full-duplex enhancements for scenarios with multiple access-points / BSS
Li-Hsiang Sun, San Jose, CA (US); Mohamed Abouelseoud, Burlingame, CA (US); Liangxiao Xin, San Jose, CA (US); and Qing Xia, San Jose, CA (US)
Assigned to SONY GROUP CORPORATION, Tokyo (JP); and SONY CORPORATION OF AMERICA, New York, NY (US)
Filed by SONY GROUP CORPORATION, Tokyo (JP); and SONY CORPORATION OF AMERICA, New York, NY (US)
Filed on Jul. 22, 2022, as Appl. No. 17/814,450.
Claims priority of provisional application 63/260,455, filed on Aug. 20, 2021.
Prior Publication US 2023/0055895 A1, Feb. 23, 2023
Int. Cl. H04L 5/16 (2006.01); H04L 5/00 (2006.01); H04W 56/00 (2009.01); H04W 84/12 (2009.01)
CPC H04L 5/16 (2013.01) [H04L 5/0048 (2013.01); H04W 56/0035 (2013.01); H04W 84/12 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An apparatus for wireless communication in a network, the apparatus comprising:
(a) a wireless communication circuit, station, which can be part of an access point (AP) configured for wirelessly communicating with other wireless stations (STAs) over a primary link and a secondary link in performing communication on a wireless local area network (WLAN) under an IEEE 802.11 protocol in which APs on the network operating as a primary AP and secondary APs perform joint transmissions to one or more non-AP stations;
(b) a processor coupled to said wireless communication circuit for operating on the WLAN as a STA;
(c) a non-transitory memory storing instructions executable by the processor; and
(d) wherein said instructions, when executed by the processor, perform one or more steps for overcoming center frequency offset and symbol timing offset caused by residual drift comprising:
(i) transmitting pilot signals within an orthogonal frequency division multiplexing (OFDM) transmission, by an AP operating as a primary AP;
(ii) wherein a portion of the overall set of pilot signals, as primary pilot signals, are only allowed to be transmitted by the primary AP, and not by APs operating as secondary APs;
(iii) wherein each said station operating as a secondary AP is configured with its own clock and upon receiving said pilot signals corrects its clock and the following symbols while performing joint transmission; and
(iv) wherein the primary AP transmits a trigger frame which is received by the secondary APs participating in the joint transmission; wherein said trigger frame establishes the center frequency and/or sampling rate of the joint transmission and synchronizing of the clocks between APs.