Xiaofei F Wang

US Patent:

20120327870, Dec 27, 2012

Filed:

Jun 21, 2012

Appl. No.:

13/529651

Inventors:

Sudheer A. Grandhi - Pleasanton CA, US
Bhaskar M. Anepu - Hummelstown PA, US
Xiaofei Wang - Cedar Grove NJ, US

Assignee:

INTERDIGITAL PATENT HOLDINGS, INC. - Wilmington DE

International Classification:

H04W 72/04

US Classification:

370329

Abstract:

Enhanced protocols and devices may be used to alleviate loss of spectrum efficiency in wideband transmission. The protocols may implement a wideband transmission opportunity (TXOP) truncation where one or more of the channels involved in communication over the wideband are released. In one scenario, a wireless transmit/receive unit (WTRU) may obtain a TXOP for a 2 MHz bandwidth mode frame transmission with another device capable of operating in a 2 MHz bandwidth mode and a 1 MHz bandwidth mode. The WTRU may conduct a request-to-send (RTS)/clear-to-send (CTS) frame exchange in the second bandwidth mode, and truncate the TXOP by transmitting a contention free (CF)-End frame in the first and second bandwidth modes. In another scenario, an AP may obtain a TXOP for a 2 MHz bandwidth mode frame transmission with a WTRU capable of both 2 MHz and 1 MHz bandwidth modes.

US Patent:

20210168860, Jun 3, 2021

Filed:

Feb 16, 2021

Appl. No.:

17/176737

Inventors:

- Wilmington DE, US
Sudheer A. Grandhi - Pleasanton CA, US
Xiaofei Wang - Cedar Grove NJ, US

Assignee:

InterDigital Patent Holdings, Inc. - Wilmington DE

International Classification:

H04W 74/04
H04W 74/06
H04W 74/08
H04W 76/11
H04W 28/06
H04W 28/26

Abstract:

Enhanced protocols and devices may be used to alleviate loss of spectrum efficiency in wideband transmission. The protocols may implement a wideband transmission opportunity (TXOP) truncation where one or more of the channels involved in communication over the wideband are released. In one scenario, an access point (AP) may receive, from a wireless transmit receive unit (WTRU), a first CF-End frame that includes a duration field and a basic service set identifier (BSSID) field that includes an individual/group bit. On a condition that the individual/group bit of the BSSID field has a value of one (1), the AP may determine that a scrambling sequence of the first CF-End frame indicates a bandwidth associated with a transmit opportunity (TXOP) being truncated by the WTRU. The AP may then transmit a second CF-End frame at the bandwidth indicated by the scrambling sequence of the first CF-End frame.

US Patent:

20190313448, Oct 10, 2019

Filed:

Jun 24, 2019

Appl. No.:

16/449898

Inventors:

- Wilmington DE, US
Sudheer A. Grandhi - Pleasanton CA, US
Xiaofei Wang - Cedar Grove NJ, US

Assignee:

InterDigital Patent Holdings, Inc. - Wilmington DE

International Classification:

H04W 74/04
H04W 74/08
H04W 76/11
H04W 28/26
H04W 74/06
H04W 28/06

Abstract:

Enhanced protocols and devices may be used to alleviate loss of spectrum efficiency in wideband transmission. The protocols may implement a wideband transmission opportunity (TXOP) truncation where one or more of the channels involved in communication over the wideband are released. In one scenario, an access point (AP) may receive, from a wireless transmit receive unit (WTRU), a first CF-End frame that includes a duration field and a basic service set identifier (BSSID) field that includes an individual/group bit. On a condition that the individual/group bit of the BSSID field has a value of one (1), the AP may determine that a scrambling sequence of the first CF-End frame indicates a bandwidth associated with a transmit opportunity (TXOP) being truncated by the WTRU. The AP may then transmit a second CF-End frame at the bandwidth indicated by the scrambling sequence of the first CF-End frame.

US Patent:

20180270038, Sep 20, 2018

Filed:

Jan 8, 2016

Appl. No.:

15/542140

Inventors:

- Wilmington DE, US
Yuan Sheng JIN - Sunnyvale CA, US
Hanqing LOU - Syosset NY, US
Xiaofei WANG - Cedar Grove NJ, US
Robert L OLESEN - Huntington NY, US

Assignee:

InterDigital Patent Holdings, Inc. - Wilmington DE

International Classification:

H04L 5/00
H04W 24/02
H04W 72/08
H04W 72/12
H04W 88/06

Abstract:

Systems, methods and instrumentalities are disclosed to transmission scheduling. A station (STA) in its own basic service set (BSS) receiving a transmission frame from an overlapping BSS (OBSS). The STA may decode preamble of the received transmission frame. The STA may determine, for example, using the decoded preamble that OBSS information and transmit scheme associated with the OBSS. On a condition that the transmit scheme associated with the OBSS is orthogonal frequency divisional multiple access (OFDMA), the STA in its own BSS may indicate to its access point (AP) that one or more channels or sub-channels that are available or not available for transmission. On a condition that the transmit scheme determined from the preamble of the transmission frame is orthogonal frequency divisional multiplexing (OFDM), the STA may determine that a channel is not available for transmission. The STA may set the channel to busy or idle.

US Patent:

20180084580, Mar 22, 2018

Filed:

Nov 30, 2017

Appl. No.:

15/827957

Inventors:

- Wilmington DE, US
Sudheer A. Grandhi - Pleasanton CA, US
Xiaofei Wang - Cedar Grove NJ, US

Assignee:

InterDigital Patent Holdings, Inc. - Wilmington DE

International Classification:

H04W 74/04
H04W 74/06
H04W 28/26
H04W 28/06
H04W 76/02
H04W 74/08
H04W 74/00
H04W 88/08

Abstract:

Enhanced protocols and devices may be used to alleviate loss of spectrum efficiency in wideband transmission. The protocols may implement a wideband transmission opportunity (TXOP) truncation where one or more of the channels involved in communication over the wideband are released. In one scenario, an access point (AP) may receive, from a wireless transmit receive unit (WTRU), a first CF-End frame that includes a duration field and a basic service set identifier (BSSID) field that includes an individual/group bit. On a condition that the individual/group bit of the BSSID field has a value of one (1), the AP may determine that a scrambling sequence of the first CF-End frame indicates a bandwidth associated with a transmit opportunity (TXOP) being truncated by the WTRU. The AP may then transmit a second CF-End frame at the bandwidth indicated by the scrambling sequence of the first CF-End frame.