Patents by Inventor Jianhan Liu

Jianhan Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10594462
    Abstract: Methods and apparatus are provided for structured resource allocation signaling. In one novel aspect, an 8-bit RU allocation filed is allocated in the HE-SIG-B common field for each 20 MHz. The structured resource signaling supports more than four MU-MIMO users. In one embodiment, the STA decodes the 8-bit RU allocation signal following a structured resource unit (RU) allocation rule, and determines the RU. In one embodiment, the STA decodes the first two bits of the 8-bit RU allocation signal to determine a first category of the RU allocation. The categories of the RU allocation includes a large RU size category indicating larger than or equal to 20 MHz RUs exist, a two 106-tone category indicating two 106-tone RUs exist, and a no-large-RU category indicating only smaller-than-242-tone RUs exist. The STA further decodes based on the category. A lookup table (LUT) for RU allocation is built and decoded based on a structured signaling rule.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: March 17, 2020
    Assignee: MEDIATEK INC.
    Inventors: Tianyu Wu, Jianhan Liu, Shengquan Hu, Thomas Edward Pare, Jr.
  • Patent number: 10594525
    Abstract: Systems and methods of expanding indication capabilities of existent PPDU preamble fields. An existing field “Doppler mode” in a preamble is redefined into a dual-use field for indicating channel variation for a short packet as well as for indicating presence of mid-amble(s) in a long packet. Particularly, for a long packet (longer than a predefined data transmission time or a longer than a predefined number of data symbols), the two possible values of the one-bit “Doppler mode” field indicate whether there is any mid-amble carrying training symbols in the payload. On the other hand, for a short packet, the two possible values in the same field indicate whether the channel for transmitting the instant packet is currently time-variant as determined by the transmitting device.
    Type: Grant
    Filed: March 22, 2018
    Date of Patent: March 17, 2020
    Assignee: MEDIATEK INC.
    Inventors: Jianhan Liu, Tianyu Wu
  • Publication number: 20200077417
    Abstract: System and method of cooperative multi-band wireless STA communication that enables full duplex operations. Frames are configured to carry band information and are selected to be transmitted simultaneously in multiple bands based on various constraints to avoid out-of-order delivery. For frames under a block ACK agreement, a transmit STA can specify the transmission bands for the frames in an ADDBA request frame. While a first band is transmitting a first frame under a block ACK agreement, the second band can be used to transmit a frame under the same block ACK agreement as, and from the same traffic flow with, the first frame. Otherwise, the second band can only be used to transmit a frame with a different TID than the first frame.
    Type: Application
    Filed: August 27, 2019
    Publication date: March 5, 2020
    Inventors: Yongho SEOK, Jianhan LIU, Gabor BAJKO, James Chih-Shi YEE
  • Patent number: 10574311
    Abstract: A method of sounding and feedback with channel quality information and reduced overhead is provided. A receiving station receives a sounding signal transmitted from an access point over multiple sub-channels of a wide channel in a wireless network. The receiving station detects channel quality based on the received sounding signal for each sub-channel. The receiving station then performs channel estimation based on the received sounding signal and thereby determining feedback information. Finally, the receiving station transmits a feedback message to the access point, the feedback message contains NULL feedback information, reduced feedback information, or channel integrity/quality indicators based on the channel quality information for each sub-channel. Based on the feedback message, the access point may repeat the sounding process, narrow the transmission bandwidth, or select only stations who have indicated uncorrupted channel sounding for MU-MMO transmission.
    Type: Grant
    Filed: June 20, 2018
    Date of Patent: February 25, 2020
    Assignee: MEDIATEK SINGAPORE PTE. LTD.
    Inventors: James June-Ming Wang, Jianhan Liu, Vishakan Ponnampalam, Chao-Chun Wang, Huanchun Ye
  • Publication number: 20200053773
    Abstract: Embodiments of the present invention provide a method and apparatus for simultaneous transmission and reception of data wirelessly using different wireless bands. The multi-link operations described herein can provide higher network throughput and improved network flexibility compared to traditional techniques to wireless communication. Embodiments of the present invention support joint or independent transmission of data over different links, and a full duplex connection can be enabled by independent multi-band operation e.g., a frequency division duplex mode.
    Type: Application
    Filed: August 6, 2019
    Publication date: February 13, 2020
    Inventors: Yongho SEOK, Jianhan LIU, Gabor BAJKO, James Chih-Shi YEE
  • Publication number: 20200037152
    Abstract: An encryption mechanism used on cooperative multi-band wireless STA architecture that enables full duplex operations. In encrypting a frame, an AAD can be constructed by using a selected MAC address, which may not be associated with a band to be used for transmitting the frame in an upcoming TXOP. An STA that supports simultaneous transmission in a multi-band operation uses the same MAC address to encrypt the frames to be transmitted on different bands. An AAD is constructed by using a same MAC address corresponding to one of the transceivers. A transmit STA may specify band information used for encryption in the MAC header, which serves to signal the receive STA to decrypt the frame by using the proper information.
    Type: Application
    Filed: July 24, 2019
    Publication date: January 30, 2020
    Inventors: Yongho SEOK, Jianhan Liu, James Chih-Shi Yee, Gabor Bajko
  • Publication number: 20200037342
    Abstract: System and method of wireless communication that enables determination of a proper channel bandwidth for an HT PPDU without requiring an earlier negotiation process. Assuming a TXOP does not involve any non-HT transmission, in case that TXOP duration information is specified in a first field in a previously transmitted HE PPDU in the same TXOP, the transmission opportunity (TXOP) holder utilizes the channel bandwidth specified in the initial HE PPDU of the same TXOP to determine the channel bandwidth for the subsequent PPDU. In the case that each previously transmitted PPDU has a value indicating duration unspecified in the first field, the TXOP holder determines the channel bandwidth for a subsequent PPDU based on the bandwidth specified in a preceding PPDU that has been transmitted in the same TXOP.
    Type: Application
    Filed: July 24, 2019
    Publication date: January 30, 2020
    Inventors: Yongho SEOK, Jianhan Liu, James Chih-Shi Yee
  • Publication number: 20200037275
    Abstract: A joint sounding mechanism used in a multi-AP system to gain channel information for joint data transmission. Multiple sounding APs can transmit a joint sounding packet that includes training symbols for the antennas of all the sounding APs with regard to the transmission channel. The antennas of the multiple sounding APs may be treated as a virtual antenna array with global antenna indexes. The joint sounding packet may include a plurality of training fields, each field corresponding to a respective antenna in the virtual antenna array. Alternatively, the joint sounding packet has subcarrier-interleaved training fields, where each sounding AP transmits training symbols on an allocated set of non-pilot subcarriers. Channel status information (CSI) can be generated by the STAs in response to the joint sounding packet and supplied to the APs. Accordingly, the APs can perform antenna beamforming and transmit a data packet jointly on the transmission channel.
    Type: Application
    Filed: June 27, 2019
    Publication date: January 30, 2020
    Inventors: Jianhan Liu, Shengquan Hu, Thomas Edward Pare, JR.
  • Patent number: 10516457
    Abstract: A method of enhanced beamforming procedure to achieve spatial reuse and thereby improving cell edge performance and area throughput is proposed. The enhanced beamforming method increases the likelihood of channel access under dense deployment condition, reduces interference to OBSS, reduces collision during reception, and increases the likelihood of spatial reuse in dense deployment scenario thus leading to higher network throughput.
    Type: Grant
    Filed: December 27, 2015
    Date of Patent: December 24, 2019
    Assignee: MEDIATEK Singapore Pte. Ltd.
    Inventors: James June-Ming Wang, Jianhan Liu, Thomas Edward Pare, Jr., Chao-Chun Wang, Chih-Shi Yee, YungPing Hsu
  • Publication number: 20190379500
    Abstract: System and method of OFDMA transmission in which mid-ambles are configured on a per-user basis for channel variation adaptation. The multiple channels used in an OFDMA transmission may use different mid-amble settings based on their respective channel characteristics. Particularly, some channels may have mid-ambles and some may have not, and mid-amble update intervals may vary across the channels. For a trigger-based (TB) uplink (UL) OFDMA transmission, an AP may signal the per-user mid-amble information in the user information fields of the trigger frame. For a downlink (DL) OFDMA transmission, an AP may signal the per-user mid-amble information in the HE SIG-B fields.
    Type: Application
    Filed: May 8, 2019
    Publication date: December 12, 2019
    Inventors: Shengquan Hu, Tianyu Wu, Jianhan Liu, Thomas Edward Pare, JR.
  • Patent number: 10484814
    Abstract: A method of combined direction finding (DF) and fine timing measurement (FTM) positioning in a wireless location area network (WLAN) is proposed. A multiple antenna IEEE 802.11 transmitting device (AP) can transmit signal preamble containing multiple Long Training Field (LTF) symbols in a radio frame from multiple antennas, which allows a receiving device (STA) to resolve multiple DF sounding signals transmitted from the multiple antennas and thereby estimating angle of departure (AoD). On the other hand, the AP can estimate angle of arrival (AoA) from radio signals transmitted from the STA. When the radial resolution error of AoD or AoA positioning increases, DF positioning and fine-timing measurement (FTM) ranging can be jointly applied to reduce the radial resolution error and extends the AoD/AoA service area with positing accuracy.
    Type: Grant
    Filed: February 24, 2015
    Date of Patent: November 19, 2019
    Assignee: MEDIATEK INC.
    Inventors: James June-Ming Wang, Jianhan Liu, Thomas Edward Pare, Jr., Tianyu Wu, Gabor Bajko, Yung-Ping Hsu
  • Publication number: 20190342916
    Abstract: A cooperative multi-band wireless station architecture that enables full duplex operations of wireless stations (STAs). Such an STA includes a WIFI transceiver and one or more additional transceivers. The two transceivers (and the associated channels) operate in mutually exclusive WIFI bands or different types of protocols and therefore can transmit and/or receive simultaneously without signal interference to each other. The multiple transceivers can perform independent clear channel assessment (CCA) and then simultaneously perform signal transmission or reception jointly or independently. In a cooperative multi-band operation, one channel may be used as an independent assistant channel and responsible for supplying assistant information relevant to a transmission opportunity (TXOP) for the other channel (primary channel) to take corresponding actions.
    Type: Application
    Filed: May 1, 2019
    Publication date: November 7, 2019
    Inventors: Jianhan Liu, Yongho Seok, Chao-Chun Wang, James June-Ming Wang, James Chih-Shi Yee, Thomas Edward PARE, JR., Yungping Hsu
  • Patent number: 10470125
    Abstract: Systems and methods of transmitting a multi-user (MU) wake-up packet in WLAN including wake-up signals to activate main radios on multiple communication devices via the wake-up radios (WURs). In the multi-user wake-up packet, a frequency channel can be divided into several sub-channels for transmitting multiple wake-up signals in FDMA. Each wake-up signal is modulated in ON/OFF Key modulation. Two adjacent wake-up signals are adequately spaced apart by a certain frequency spacing to reduce adjacent channel interferences. Once a WUR on a receive device receives the packet, it generates a wake-up indication to wake up the main radio for active data communication. The MU wake-up packet may also include a sequence of multiple wake-up signals transmitted using the same sub-channel and cascaded in a time-domain. A reconfiguration window may be inserted between consecutive wake-up signals on the same sub-channel, and between a legacy preamble and the following wakeup signals.
    Type: Grant
    Filed: December 22, 2017
    Date of Patent: November 5, 2019
    Assignee: MEDIATEK INC.
    Inventors: Jianhan Liu, Thomas Edward Pare, Jr., Keng Leong Fong
  • Publication number: 20190297575
    Abstract: Systems and methods of transmitting a multi-user (MU) wake-up packet in FDMA. In the wake-up setup stage, an STA informs the AP that it can resolve an MU wake-up packet transmitted in FDMA. Accordingly, AP allocates a frequency channel to the STA in a WUR setup response frame which indicates a channel offset relative to the primary channel. Moreover, if a WUR channel allocated to an STA is inaccessible or there is on pending wake-up signal for the STA, no wake-up signal is included in the MU wake-up packet while any other accessible allocated channels may still be utilized for transmitting the scheduled wake-up signals. During such a transmission, an inaccessible channel may be punctured; and an accessible channel having no pending wake-up signal may be used to carry an invalid wake-up signal or a legacy preamble followed with no wake-up signal.
    Type: Application
    Filed: March 19, 2019
    Publication date: September 26, 2019
    Inventors: Yongho SEOK, Jianhan Liu, James Chih-Shi YEE, Thomas Edward PARE, Jr.
  • Publication number: 20190288767
    Abstract: Systems and methods of WLAN communication including efficient spatial reuse mechanisms for relay transmissions between a repeater network and non-AP STAs in OFDMA. The non-AP STAs are grouped based on their connectivity with the individual repeaters and the radio coverage regions of the repeaters. Each group is either a non-overlapping group with the constituent non-AP STAs located in a non-overlapping coverage region of a particular repeater, or an overlapping group with the constituent non-AP STAs located in an overlapping coverage region of two or more repeaters. Based on the grouping, certain RUs (or subchannels) are reused for multiple groups without causing inter-group interference, thereby expanding the bandwidths used in the relay operations. RU allocation based on grouping can be used in combination with transmit power adjustment to achieve efficient spatial reuse in OFDMA.
    Type: Application
    Filed: March 12, 2019
    Publication date: September 19, 2019
    Inventors: James June-Ming Wang, Thomas Edward PARE, Jr., Yongho Seok, Gabor Bajko, Jianhan Liu, Tianyu Wu
  • Patent number: 10411753
    Abstract: The present invention provides a method and an electronic apparatus for transmitting a packet with changeable spreading factor. The method comprises: utilizing a spreading circuit to select a spreading factor from a plurality of spreading factors according to a transmitting condition to adjust a spreading for the packet; and transmitting the packet. The electronic apparatus comprises: a spreading circuit and a transmitting circuit. The spreading circuit is utilized for selecting a spreading factor from a plurality of spreading factors according to a transmitting condition to adjust the spreading for the packet. The transmitting circuit is coupled to the spreading circuit, and utilized for transmitting the packet.
    Type: Grant
    Filed: March 28, 2016
    Date of Patent: September 10, 2019
    Assignee: MEDIATEK INC.
    Inventors: Jianhan Liu, Chien-Fang Hsu
  • Patent number: 10405139
    Abstract: An emergency mode is provided in a portable electronic device for locating a survivor in a disaster. The device includes a wireless antenna to transmit and receive wireless signals; a memory to store one or more identifiers; a user interface to receive a command that enables the emergency mode. The device also includes one or more processors, which, in response to the command, detect via the wireless receiver a predetermined identifier that matches a stored identifier identifying a sender of the predetermined identifier as a trusted node. When the predetermined identifier and a timing measurement frame are received from the trusted node, the device sends a response to the trusted node to indicate its presence.
    Type: Grant
    Filed: March 27, 2017
    Date of Patent: September 3, 2019
    Assignee: MediaTek Inc.
    Inventors: Chuen-Shen Bernard Shung, Jianhan Liu, George Chien, YungPing Hsu, Yasantha Rajakarunanayake, Dingchung Jann, Tom Hsiou-Cheng Kao
  • Publication number: 20190238288
    Abstract: Systems and methods of transmitting a PPDU to or from a single user station (STA) in an OFDMA transmission by using multiple RUs. An access point (AP) allocates multiple RUs to an STA for an OFDMA transmission and correspondingly specifies the STA ID repeatedly in the user specific field of a SIG-B field in a downlink PPDU, or in the user information fields of a trigger frame. Alternatively, multiple AIDs of the STA can be specified in the user specific field or the user information fields instead of repeating the same STA ID. An indication may be inserted in the SIG-A field to indicate that the enhanced RU allocation scheme is used for the OFDMA transmission.
    Type: Application
    Filed: January 23, 2019
    Publication date: August 1, 2019
    Inventors: Jianhan LIU, Shengquan Hu, Yongho Seok, Thomas Edward Pare, JR., Yungping Hsu
  • Publication number: 20190238195
    Abstract: Systems and methods of transmitting a PPDU to or from a single user station (STA) in an MIMO transmission by using unequal MCSs. An access point (AP) allocates a plurality of spatial streams to the STA and assigned them into groups for the MIMO transmission. Multiple unequal MCSs are assigned to the different spatial stream groups. Correspondingly the STA ID is repeatedly specified in the user block fields of a SIG-B field of a downlink PPDU, or in the user information fields of a trigger frame. Alternatively, multiple AIDs of the STA can be specified in the user block fields or the user information fields instead of repeating the same STA ID. An indication may be inserted in the SIG-A field to indicate that the grouped-based unequal MCSs scheme is used for the MIMO transmission.
    Type: Application
    Filed: January 23, 2019
    Publication date: August 1, 2019
    Inventors: Jianhan Liu, Shengquan Hu, Yongho Seok, Thomas Edward Pare, JR., Yungping Hsu
  • Publication number: 20190215037
    Abstract: Null Data Packet Sounding for preamble punctured Physical Layer Convergence Procedure Protocol Data Unit (PPDU) for efficient use of a wireless channel bandwidth where a primary service co-exists.
    Type: Application
    Filed: January 3, 2019
    Publication date: July 11, 2019
    Inventors: Yongho SEOK, Jianhan LIU, Chao-Chun Wang, James Chih-Shi YEE