Patents by Inventor Christiaan A. Hartman

Christiaan A. Hartman 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: 10285200
    Abstract: An access point selects a channel access policy for an electronic device in a wireless local area network (WLAN). During operation, an interface circuit of the access point receives a channel access preference from the electronic device. The channel access preference includes: a multi-user trigger-based channel access technique, a single-user contention-based channel access technique, or both. The interface circuit selects the channel access policy for the electronic device based, at least in part, on the received channel access preference. The channel access policy can also be selected based at least in part on a communication performance metric associated with communication in the WLAN. The interface circuit communicates the selected channel access policy to the electronic device, which subsequently accesses a communication channel and communicates packets with the access point in accordance with the channel access policy.
    Type: Grant
    Filed: January 10, 2017
    Date of Patent: May 7, 2019
    Assignee: Apple Inc.
    Inventors: Guoqing Li, Christiaan A. Hartman, Ashok Ranganath, Joonsuk Kim, Matthew L. Semersky, Oren Shani, Su Khiong Yong, Yong Liu
  • Patent number: 10285040
    Abstract: In some embodiments, one or more wireless stations operate to configure direct communication with neighboring mobile stations, e.g., direct communication between the wireless stations without utilizing an intermediate access point. Embodiments of the disclosure relate to accelerated service discovery between peer devices. In some embodiments, a wireless device may broadcast a probe beacon on one or more discovery channels. The wireless device may then scan the discovery channels for an extended period of time. The wireless device may receive a response from a peer device and transmit further service information to the peer device in an availability window indicated in the response.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: May 7, 2019
    Assignee: Apple Inc.
    Inventors: Yong Liu, Christiaan A. Hartman, Guoqing Li, Lawrie Kurian, Peter N. Heerboth, Su Khiong Yong
  • Patent number: 10277424
    Abstract: Time, frequency and waveform division multiplex schemes are used to efficiently estimate multiple uplink channels in a Wireless Local Area Network (WLAN). Orthogonal Frequency Division Multiple Access (OFDMA) and multi-user Multiple Input Multiple Output (MU-MIMO) approaches provide efficient uplink data transmission. An Access Point (AP) communicates with multiple Stations (STAs) in the WLAN. In some approaches, two or more STAs are addressed and the two or more STAs respond at the same time. The AP receives a composite signal and separates the responses to estimate the uplink channel from each STA. After the AP learns the uplink channels, the AP triggers data transmission from one or more of the WLAN STAs by sending a synchronizing trigger message. In some embodiments, the STAs respond simultaneously with data transmissions to the AP.
    Type: Grant
    Filed: September 28, 2016
    Date of Patent: April 30, 2019
    Assignee: Apple Inc.
    Inventors: Guoqing Li, Joonsuk Kim, Yong Liu, Christiaan A. Hartman, Su Khiong Yong
  • Publication number: 20190124593
    Abstract: A station (STA) of a wireless local area network (WLAN) transitions implicitly between power management (PM) modes or PM states, without providing an explicit indication of the PM mode/state change to an access point (AP) of the WLAN. Transitions include changes between an active mode and a power save (PS) mode, or between an awake state and a doze state of the PS mode. Transitions occur immediately after receipt of a beacon indicating pending data for the STA, after an offset time indicated in the beacon, or at a specific wake time negotiated with the AP. After data reception is complete, the STA transitions implicitly to the PS mode or a doze state of the PS mode, after a power save inactivity timeout period or after receiving an indication that data transmission is complete.
    Type: Application
    Filed: September 19, 2018
    Publication date: April 25, 2019
    Inventors: Chiu Ngok E. WONG, Syed A. MUJTABA, Christiaan A. HARTMAN, Joonsuk KIM
  • Patent number: 10271293
    Abstract: A system, apparatus and method for organizing devices in a peer-to-peer communication environment. A number of devices synchronize among themselves and select masters (or synchronization stations) to organize the devices into a hierarchy. Master devices have associated preference values reflecting their preference or suitability to be a master device, and broadcast synchronization frames to keep devices synchronized. When multiple devices in one or more hierarchies execute a common application or service, they form a private group to exchange or share data (e.g., play a game, transfer a file). All devices in the hierarchy maintain and advertise a public or default identifier of the hierarchy, and all devices in the private group maintain and advertise a private identifier specific to the group. Members of the group synchronize under a top group master (or root sync station), which synchronizes with a master that is part of the hierarchy.
    Type: Grant
    Filed: January 8, 2013
    Date of Patent: April 23, 2019
    Assignee: Apple Inc.
    Inventors: Pierre B. Vandwalle, Christiaan A. Hartman
  • Patent number: 10271180
    Abstract: In some embodiments, one or more wireless stations operate to configure direct communication with neighboring mobile stations, e.g., direct communication between the wireless stations without utilizing an intermediate access point. Embodiments of the disclosure relate to a mechanism for a device to perform multicast communications amongst a group of peer devices. Embodiments described herein provide mechanisms for initiation (or establishment) and scheduling of a multicast group as well as enrollment of a device into a multicast group, merging of multicast groups, and termination of multicast groups.
    Type: Grant
    Filed: January 12, 2017
    Date of Patent: April 23, 2019
    Assignee: Apple Inc.
    Inventors: Yong Liu, Su Khiong Yong, Christiaan A. Hartman, Lawrie Kurian, Peter N. Heerboth, Guoqing Li
  • Patent number: 10264602
    Abstract: Embodiments include a method, computer program product, and system for grouping electronic devices into contention groups to reduce uplink Orthogonal Frequency-Division Multiple Access (OFDMA) random access (OFDMA-RA) collisions. An access point may explicitly assign an electronic device to a contention group, or the electronic device may implicitly determine an assignment to the contention group. To explicitly assign a device to a contention group, the access point may randomly assign or assign based on a criteria of the electronic device. Examples of criteria include an association identifier (AID), a traffic type/quality of service (QoS) category, a power saving preference, and an association status. The electronic device may implicitly determine a contention group assignment based on the total number of contention groups.
    Type: Grant
    Filed: April 14, 2016
    Date of Patent: April 16, 2019
    Assignee: Apple Inc.
    Inventors: Guoqing Li, Joonsuk Kim, Christiaan A. Hartman, Syed Aon Mujtaba, Chiu Ngok E. Wong, Yong Liu, Su Khiong Yong
  • Patent number: 10237870
    Abstract: Managing orthogonal frequency division multiple access (OFDMA) uplink acknowledgements is described herein. An example system can include an interface circuit to generate a physical layer convergence protocol data unit (PPDU) including a physical layer preamble, a first sub-channel field corresponding to a first station, and a second sub-channel field corresponding to a second station. The first sub-channel field can carry a first unicast trigger corresponding to the first station, and the second sub-channel field can carry a second unicast trigger corresponding to the second station. The interface circuit can also transmit the PPDU to the first and second stations.
    Type: Grant
    Filed: May 5, 2016
    Date of Patent: March 19, 2019
    Assignee: Apple Inc.
    Inventors: Guoqing Li, Joonsuk Kim, Christiaan A. Hartman, Yong Liu, Chiu Ngok E. Wong, Syed Aon Mujtaba, Su Khiong Yong
  • Publication number: 20190082443
    Abstract: An electronic device that determines a transmission schedule is described. This electronic device may include an interface circuit that communicates with a recipient electronic device. During operation, the electronic device may receive a frame with scheduling-request information that is associated with the recipient electronic device. The scheduling-request information may include a buffer status report for persistent traffic, and the frame may be compatible with an IEEE 802.11 communication protocol. For example, the frame may include a scheduling-request management frame. Alternatively, the frame may include a data frame and the scheduling-request information may be included in a media access control (MAC) frame header, such as a high-efficiency (HE) variant high-throughput (HT) control header. Then, the electronic device may determine the transmission schedule based at least in part on the scheduling-request information.
    Type: Application
    Filed: September 11, 2018
    Publication date: March 14, 2019
    Inventors: Guoqing Li, Christiaan A. Hartman, Daniel R. Borges, Jarkko L. Kneckt, Oren Shani, Tushar R. Shah, Xiaowen Wang, Yong Liu, Christian W. Mucke, Joseph Hakim, Farouk Belghoul, Ayman F. Naguib, Karan Sanghi, Cahya Adiansyah Masputra
  • Patent number: 10231258
    Abstract: In some embodiments, one or more wireless stations operate to configure direct communication with neighboring mobile stations, e.g., direct communication between the wireless stations without utilizing an intermediate access point. Embodiments of the disclosure relate to NAN datapath scheduling and NAN pre-datapath operation setup and scheduling. The NAN datapath embodiments described herein provide a mechanism through which devices can communicate and provide services. In particular, embodiments described herein relate to techniques for devices (e.g., NAN devices) to propose and confirm schedule updates. The datapath model, and in particular the techniques described herein, may be implemented for unicast and multicast communication between wireless stations.
    Type: Grant
    Filed: August 23, 2017
    Date of Patent: March 12, 2019
    Assignee: Apple Inc.
    Inventors: Yong Liu, Lawrie Kurian, Peter N. Heerboth, Christiaan A. Hartman
  • Publication number: 20190075609
    Abstract: One or more wireless stations may operate to configure direct communication with neighboring mobile stations, e.g., direct communication between the wireless stations without utilizing an intermediate access point. A mechanism for a wireless station to transmit a paging beacon outside of a paging window may include establishing a paged data link with a peer station, determining that one or more data frames associated with the paged data link are pending transmission, and transmitting a beacon to the peer station outside of a scheduled paging window of the paged data link. The beacon may include a paging attribute indicating there are pending data frames.
    Type: Application
    Filed: August 23, 2018
    Publication date: March 7, 2019
    Inventors: Yong Liu, Christiaan A. Hartman, Guoqing Li, Lawrie Kurian, Peter N. Heerboth, Su Khiong Yong
  • Publication number: 20190075519
    Abstract: A recipient electronic device that receives a wake-up frame is described. This recipient electronic device may include an interface circuit that communicates with an electronic device, where the interface circuit includes a main radio and a wake-up radio (WUR) that at least selectively transitions the main radio from a lower-power mode to a higher-power mode. During operation, the WUR receives the wake-up frame intended for the recipient electronic device, where the wake-up frame comprises a payload field with data. For example, the wake-up frame may specify: a total size of the wake-up frame, and/or a size of the payload field. In response to the wake-up frame, the WUR selectively transitions the main radio from the lower-power mode to the higher-power mode. Moreover, the main radio provides an acknowledgment associated with the recipient electronic device that indicates that the recipient electronic device received the wake-up frame.
    Type: Application
    Filed: September 4, 2018
    Publication date: March 7, 2019
    Inventors: Guoqing Li, Christiaan A. Hartman, Zheng Zeng
  • Publication number: 20190075521
    Abstract: An interface circuit in an electronic device (such as an access point) may receive a wake-up-radio (WUR)-setup request associated with a recipient electronic device, where the WUR-setup request specifies one or more proposed data criteria or wake-up criteria that indicate when a wake-up frame is to be transmitted to the recipient electronic device. In response, the electronic device may determine one or more data criteria (or wake-up criteria) for use based at least in part on the one or more proposed data criteria. Then, the interface circuit may provide a WUR-setup response intended for the recipient electronic device, where the WUR-setup response indicates acceptance of the one or more proposed data criteria for use as the one or more data criteria or a proposed modification of at least one of the one or more proposed data criteria.
    Type: Application
    Filed: August 27, 2018
    Publication date: March 7, 2019
    Inventors: Jarkko L. Kneckt, Yong Liu, Su Khiong Yong, Christiaan A. Hartman, Guoqing Li
  • Publication number: 20190069231
    Abstract: An interface circuit in an electronic device (such as an access point) may utilize a configurable wake-up-frame format. During operation, the interface circuit may receive a wake-up-radio (WUR)-setup request associated with a recipient electronic device, where the WUR-setup request specifies a proposed configurable wake-up-frame format. In response, the electronic device may determine the configurable wake-up-frame format to be used based at least in part on the proposed configurable wake-up-frame format. Then, the interface circuit may provide a WUR-setup response intended for the recipient electronic device, where the WUR-setup response specifies the configurable wake-up-frame format selected for use. Note that the configurable wake-up-frame format may specify a payload length in a wake-up frame and/or one or more operations of at least one of the recipient electronic device or the electronic device after the wake-up frame is transmitted by the electronic device.
    Type: Application
    Filed: August 23, 2018
    Publication date: February 28, 2019
    Inventors: Jarkko L. Kneckt, Matthew L. Semersky, Christiaan A. Hartman, Oren Shani, Yong Liu, Xiaowen Wang, Tushar R. Shah, Yoel Boger, Rajneesh Kumar, Josef Peery, Christian W. Mucke, Guoqing Li
  • Publication number: 20190069239
    Abstract: The present disclosure describes an electronic device configured to concurrently transmit wake-up radio (WUR) packets in a duplicated WUR transmission mode, non-duplicated WUR transmission mode, and/or mixed WUR transmission mode in one or more channels of a wideband basic service set (BSS) communication. Receiving electronic devices may be grouped together and assigned to monitor for the WUR packets. For example, the receiving electronic devices may be assigned to a position within the one or more channels to monitor for the WUR packets.
    Type: Application
    Filed: June 29, 2018
    Publication date: February 28, 2019
    Applicant: Apple Inc.
    Inventors: Guoqing Li, Yong Liu, Christiaan A. Hartman, Jarkko L. Kneckt, Oren Shani
  • Patent number: 10219224
    Abstract: Embodiments described herein relate to providing reduced power consumption in wireless communication systems, such as 802.11 WLAN systems. Timing information regarding power save opportunities (PSOPs) may be provided in communication frames, which may inform mobile devices of expected frame exchange periods during which they may transition to a Doze state. Additional PSOP information may be included in beacon frames, which may inform mobile devices of expected multicast periods during which they may transition to a Doze state. This may operate to provide improvements in terms of power consumption.
    Type: Grant
    Filed: July 6, 2018
    Date of Patent: February 26, 2019
    Assignee: Apple Inc.
    Inventors: Chiu Ngok E. Wong, Christiaan A. Hartman, Joonsuk Kim, Syed Aon Mujtaba, Yong Liu, Su Khiong Yong
  • Patent number: 10212574
    Abstract: In some embodiments, one or more wireless stations operate to configure Neighbor Awareness Networking (NAN)—direct communication between neighboring wireless stations, e.g., without utilizing an intermediate access point. Embodiments of the disclosure relate to NAN datapath configuration. The NAN datapath embodiments described herein provide a mechanism through which devices can communicate and provide services. Aspects of the datapath development include datapath scheduling, including datapath setup and scheduling attributes, scheduler rank management, and further NAN discovery. The datapath model may be implemented for unicast and multicast communication between wireless stations.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: February 19, 2019
    Assignee: Apple Inc.
    Inventors: Yong Liu, Christiaan A. Hartman, Daniel R. Borges, Peter Heerboth, Lawrie Kurian, Su Khiong Yong, Anand Rajagopalan, Saravanan Balasubramaniyan, Tashbeeb Haque, Andreas Wolf, Guoqing Li, Lilach Zukerman, Oren Shani
  • Publication number: 20190053155
    Abstract: An interface circuit in an electronic device (such as an access point) may provide a targeted wake-up time (TWT) service period (SP) schedule to a recipient electronic device. During operation the interface circuit may receive a TWT setup request associated with the recipient electronic device, where the TWT setup request includes non-availability information specifying one or more times when the recipient electronic device will be unavailable. For example, the non-availability information may include one or more times when the recipient electronic device has limited ability to transmit and/or receive. The interface circuit may provide a TWT setup response for the recipient electronic device, where the TWT setup response includes information specifying the TWT SP schedule for the recipient electronic device that includes at least one of: a TWT SP start time, a TWT SP duration, or an interval between TWT SPs.
    Type: Application
    Filed: August 2, 2018
    Publication date: February 14, 2019
    Inventors: Jarkko L. Kneckt, Chiu Ngok E. Wong, Yong Liu, Christiaan A. Hartman, Guoqing Li, Daniel R. Borges
  • Patent number: 10206190
    Abstract: A system, apparatus and method for selecting one or more synchronization stations, or masters, in a peer-to-peer communication environment. Synchronization (or sync) stations broadcast periodic synchronization frames to advertise future availability windows, during which devices rendezvous for discovery and communication. Devices that can act as sync stations advertise preference values, which indicate their preference or suitability for the role. All devices execute the same algorithm to sort the preference values and identify a root sync station and any number of branch sync stations; leaf devices synchronize with the root or a branch sync station. This passive synchronization scheme allows individual devices to conserve power, because they need not actively discover other devices and services, and can power off their radios for periods of time without sacrificing discoverability.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: February 12, 2019
    Assignee: Apple Inc.
    Inventors: Robert J. Stacey, Pierre B. Vandwalle, Christiaan A. Hartman
  • Patent number: 10194468
    Abstract: Determining wireless local area network (WLAN) channel medium usage information by WLAN access points (APs) and WLAN stations (STAs) is disclosed. A new medium access control (MAC) duration field in a request to send (RTS) message provides a duration value to be conveyed in a subsequent clear to send (CTS) message. A channel or bandwidth can then be quickly used if an addressed STA does not respond to the RTS message. Also, a STA recognizes an unexpected silence and accesses the medium when a trigger frame is followed by a CTS timeout interval. In a third embodiment, an AP requests that STAs monitor particular channels to obtain network allocation vector (NAV) information. The STAs then respond (or informatively, do not respond) to RTS messages; thus, allowing the AP and other listening devices to determine channel medium information. The AP can then schedule data exchanges based on the determined information.
    Type: Grant
    Filed: March 3, 2017
    Date of Patent: January 29, 2019
    Assignee: Apple Inc.
    Inventors: Jarkko Kneckt, Guoqing Li, Christiaan A. Hartman, Joonsuk Kim