Qualcomm Incorporated

Shu Du

Zhanfeng Jia

Qinghai Gao

Ning Zhang

Sandip HomChaudhuri

James Simon Cho

Guido Robert Frederiks

Chin-Hung Chen

Balaji Srinivasan Babu

Sarvesh Shrivastava

Veerendra Bhora

Paul J Husted

Rahul Tandra

Vincent K Jones

Arunkumar Jayaraman

Sumeet Kumar

Sohani Ganesh Rao

Alireza Raissinia

Jibing Wang

Didier Johannes Richard Van Nee

Kai Shi

Matthew Daniel Smith

Zhen Xie

Srinivasa Kumar Duvvuri

Vipin Kumar Mehta

Sandip Homchaudhuri

Vishnu Vardhan Bala Krishnan

Methods and devices are described for wireless communications associated with a multidimensional algorithm for roaming. In one aspect, an access point (or like device) transmits a beacon signal. The access point receives, from a station in receipt of the beacon signal, a probe signal including at least one metric. The access point transmits a response signal based at least in part on the received probe signal, the response signal including information associated with the at least one metric.

Multidimensional algorithm for roaming

Methods, systems, devices, and apparatuses are described for wireless communications in which first type of traffic may be transmitted from a gateway access point (AP) directly to a station. Beacon signals transmitted to the station are transmitted as part of the first type of traffic. A second type of traffic may be transmitted from the gateway AP to the station via at least one relay AP. The first type of traffic may include low-throughput traffic and may be transmitted over a long-range radio link (e.g., 2 GHz band link or sub-1 GHz band link). The second type of traffic may include high-throughput traffic and may be transmitted over at least one short-range radio link (e.g., 5 GHz band link). The gateway AP may receive low-throughput traffic directly from the station and high-throughput traffic from the station via the at least one relay AP.

Multi-band management of wireless relaying networks

Methods, systems, and devices are described for establishing a virtual communication link including at least a first and second physical link between two devices. A single virtual packet queue of a device may receive one or more data packets to be transmitted via the virtual communication link. The single virtual packet queue may attach a virtual sequence number to each of the one or more data packets and send the one or more data packets to one or more of the first or the second physical link according to the assigned virtual sequence numbers. The one or more packets may then be communicated via the first and/or second physical links according to link specific sequence numbers, such as medium access control (MAC) sequence numbers, assigned to the one or more data packets by the first and/or second physical links.

Link aggregation in wireless local area networks

Methods, systems, and devices are described for power conservation in a wireless communications system through efficient transmissions and acknowledgements of information between an AP and a station. The time between a determination by a station to enter a power saving mode and entering network sleep mode by the station may be reduced through a transmission, by an AP, of an MPDU to the station successive to an SIFS after transmission of an acknowledgement to the station of a PS-Poll frame from the station. The time to enter a power saving mode by a station may also be reduced through transmission of A-MPDUs in which a last MPDU of the A-MPDU has an indicator bit cleared to indicate no additional data is to be transmitted. An AP may prevent a retransmission of an MPDU to the station in the absence of an acknowledgement from the station, to further enhance efficiency.

Access point response to PS-Poll

A method of providing rate adaptation in a multi-user wireless communication system including single-user beamforming (SU-BF) and multi-user multiple-input multiple-output (MU-MIMO) is described. In this method, a master rate, which is a modulation and coding scheme (MCS) for the SU-BF, is determined. An MCS for each transmit mode is derived from the master rate using a rate mapping. Using the results from the mapping, the master rate, instead of the MCS for each transmit mode, is tracked. In one embodiment, a mapping calibration is periodically performed.

Method and system for unified rate adaptation for SU-BF and MU-MIMO operation

One innovation includes an apparatus, for wirelessly communicating with a communication system via a first wireless channel and a second wireless channel, including a memory unit that is configured to store a first data packet and a second data packet, the first data packet and the second data packet have consecutive sequence numbers. The apparatus further includes a processor configured to retrieve the first data packet and the second data packet from the memory unit, a transceiver that is configured to transmit the first data packet to the communication system via the first channel, to receive a first acknowledgement from the communication system and to transmit the second data packet to the communication system via the second channel after the processor detects that the first acknowledgement comprises a positive acknowledgement of the first reception information.

Systems and methods for seamless data stream transfer during band switch between wireless stations

An access point determines the buffered data for each station of a plurality of stations in a BSS and groups the stations with similar station characteristics. The transmission time to the stations in a group can be apportioned. The groups can be ordered based on station characteristics and a transmission history. A sounding for a group can be performed based on the order. The MU-MIMO transmission for the group can be performed until a first condition is met. If the first condition is met, then the sounding and the MU-MIMO transmission for a next group can be performed, according to the order, until a second condition is met. The first condition can include an apportioned transmission time having expired and/or the buffers for the group being flushed. The second condition can include new data having been buffered by the AP and/or all buffered data having been transmitted.

Scheduling transmission for multi-user, multiple-input, multiple-output data

Various aspects of apparatus for accessing a network through a wireless access point and methods of power savings for such apparatus include autonomously alternating between a listen state and the sleep state during a time period in which no data is detected from the remote apparatus, and progressively increase the sleep state interval during the time period for at least a portion of the time period.

Power saving modes in wireless devices

An access point may transmit, to a first wireless device, a message indicating a busy period of the access point. The busy period is a time during which the access point will perform wireless operations with at least a second wireless device different from the first wireless device. During the busy period, the access point may refrain from transmitting from the access point to the first wireless device. The message indicating the busy period may include a duration of the busy period. The message indicating the busy period may be included in a portion of a data transmission to the first wireless device. The first wireless device may enter a low power mode (e.g., sleep operating state) responsive to the busy period.

Indicating a busy period in a wireless network

Methods, devices, and apparatuses are described for wireless communications using a multidimensional algorithm for roaming. In one aspect, an initial set of candidate access points (APs) is produced by a station using a roaming scan. The initial set may be identified based at least in part on an initial metric (e.g., beacon signal strength). A probe signal may be transmitted by the station to at least one of the candidate APs in the initial set and information may be received in response to the probe signals. The station may then identify a reduced set from the initial set based at least in part on the received information, where the reduced set is used to select a target AP. At least one additional metric may be identified and the probe signal may be configured to obtain information corresponding to the additional metrics. This information may be used by the station to select the candidate APs in the reduced set.

In adaptive modulation and coding scheme (MCS) selection for directional antenna systems, at least one table is defined that maps different ranges of signal quality values to different sets of MCS parameters. In some implementations, each range corresponds to a separate table (e.g., a given table will include the MCS and other information for that range of signal quality values). In the event an abrupt change in signal quality is detected (e.g., a change in received signal strength greater than or equal to a defined threshold), instead of using a conventional rate selection algorithm, a new MCS is selected through the use of the ranges from the table(s). In this way, a relatively large change in MCS may be accommodated, if warranted by the change in signal quality.

Selecting a modulation and coding scheme for beamformed communication

Various aspects of the disclosure described herein provide for optimizing rate control during a selection of a communications profile from a set of communications profiles by taking into account effective frame aggregation size as a function of packet error rate (PER). An expected throughput may also be determined for each communications profile and updated after each transmission so that a communications profile having the highest expected throughput may be chosen for a particular frame transmission.

Method and apparatus for optimizing rate control based on packet aggregation considerations

A method of providing feedback on channel observations to a transmitter includes observing a channel at a receiver based on received signals from the transmitter and determining whether a packet error rate (PER) is rising based on the observing. The receiver determines whether a rising PER is caused by channel noise or interference, and transmits a message to the transmitter indicating the cause of the rising PER. The cause may be encoded in reserved bits of a block acknowledgement (BA) frame or an Acknowledge (ACK) frame, or in a modulation coding scheme (MCS) used to transmit the message. The cause may be detected in response to SNR/RSSI level of received signals, or a number of receiver restarts. The transmitter may change the transmit rate adaptation algorithm to use a lower MCS if channel noise causes the rising PER, and a higher MCS if interference causes the rising PER.

Methods permitting a wireless system receiver to determine and report channel conditions to a system transmitter

Various aspects of apparatus for accessing a network through a wireless access point and methods of power savings for such apparatus include scheduling a sleep state interval, entering a sleep state at the beginning of the scheduled sleep interval, and buffering data during the sleep state for transmission following the sleep state.

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Milpitas, CA, United States of America

Shu Du