Abstract: This invention relates to switching power saving modes and rescheduling communication frames for various periods of a beacon interval (BI) defined under WGA Draft Specification 0.8 for the personal basic service set (PBSS) and infrastructure BSS to achieve further power savings and other advantages. Stations can be awake during a contention-based period (CBP) if it is in active state and can schedule frames during a service period (SP) to allow the assigned receiver to transmit to the assigned initiator. Stations in a group can schedule a group address frame to be sent during the CBP and group SP of a specific periodic BI. Stations in peer-to-peer connection may directly notify its peer stations of its power saving mode and wakeup schedule. Stations of an infrastructure basic service set (BSS) can also use the same power saving mechanism as stations of a PBSS noting a difference where each BI will be an access point's (AP's) awake BI.

Abstract: Multiple virtual MAC addresses may be added to WGA devices that may have different traffic streams to another device that requires different services, thus creating distinct MAC and device level implications. Beamforming training can be done at the device level for all virtual MAC addresses. Wakeup, doze, and ATIM power save can be done at the device level depending on the frames received. Authentication, deauthentication, association, and deassociation can be done variously at both levels. Further MSDUs can be aggregated for the multiple MAC addresses.

Abstract: A wireless local area network system establishes a PASSPOINT™ connection between a mobile station and a hotspot using an enhanced single SSID method or an enhanced dual SSID method. In the dual SSID method, an access point associates and authenticates a mobile device to a secondary SSID of the access point during enrollment and provisioning. After enrollment, the access point authenticates the mobile station to a primary SSID of the access point using the credential that the mobile station received from an online sign-up (“OSU”) server in connection with the secondary SSID. In the single SSID method, an access point performs two levels of authentication. During authentication, communications are limited to an 802.1x controlled port running on the mobile station and access point. After a first authentication, communications between the OSU server and the mobile station are unblocked. After the second authentication, all traffic from the mobile station is unblocked.

Abstract: In an embodiment, a transmitter includes first and second transmission paths. The first transmission path is configurable to generate first pilot clusters each including a respective first pilot subsymbol in a first cluster position, and the second transmission path is configurable to generate second pilot clusters each including a respective second pilot subsymbol in a second cluster position such that a vector formed by the first pilot subsymbols is orthogonal to a vector formed by the second pilot subsymbols. For example, where such a transmitter transmits simultaneous orthogonal-frequency-division-multiplexed (OFDM) signals (e.g., MIMO-OFDM signals) over respective channels that may impart inter-carrier interference (ICI) to the signals due to Doppler spread, the pattern of the pilot symbols that compose the pilot clusters may allow a receiver of these signals to use a recursive algorithm, such as a Vector State Scalar Observation (VSSO) Kalman algorithm, to estimate the responses of these channels.

Abstract: This invention relates to switching power saving modes and rescheduling communication frames for various periods of a beacon interval (BI) defined under WGA Draft Specification 0.8 for the personal basic service set (PBSS) and infrastructure BSS to achieve further power savings and other advantages. Stations can be awake during a contention-based period (CBP) if it is in active state and can schedule frames during a service period (SP) to allow the assigned receiver to transmit to the assigned initiator. Stations in a group can schedule a group address frame to be sent during the CBP and group SP of a specific periodic BI. Stations in peer-to-peer connection may directly notify its peer stations of its power saving mode and wakeup schedule. Stations of an infrastructure basic service set (BSS) can also use the same power saving mechanism as stations of a PBSS noting a difference where each BI will be an access point's (AP's) awake BI.

Abstract: An additional cyclic redundancy check (CRC) is inserted in IEEE 802.11 beacon or data frames prior to the end of the frame, at a location following information sufficient for the receiving station to determine whether the frame is from an overlapping basic service set or intended for a different station and to extract other necessary or useful information such as a time of the next full beacon. Upon detecting the CRC, the receiving STA can terminate reception of the frame early to conserve power, and then enter a low power operational mode to further conserve power.

Abstract: Multiple virtual MAC addresses may be added to WGA devices that may have different traffic streams to another device that requires different services, thus creating distinct MAC and device level implications. Beamforming training can be done at the device level for all virtual MAC addresses. Wakeup, doze, and ATIM power save can be done at the device level depending on the frames received. Authentication, deauthentication, association, and deassociation can be done variously at both levels. Further MSDUs can be aggregated for the multiple MAC addresses.

Abstract: An access point (AP) associated with a several mobile stations (STAs) implements a slot-based power save poll (PS-Poll) method. The AP divides a slot-based access period into multiple time slots and allocates each time slot to either a STA determined to have slot-based PS-Poll capabilities or a STA determined to have buffered data present at the AP. The AP creates a traffic indication map (TIM) having a number of bits equal to the number of stations associated with the AP, and then transmits a beacon including the TIM. The TIM indicates to a slot-based PS-Poll capable STA which time slots are assigned to a selected set of associated stations. After receiving the beacon from the AP, the STA refrains from attempting to communicate with the AP outside the time slot assigned to the STA, yet transmits information to the AP during the time slot assigned to the STA.

Abstract: A first base station is associated with a first quiet period, and a second base station is associated with a second quiet period. The quiet periods are coordinated so that an amount of overlap between the quiet periods is acceptable. For example, the quiet periods could be coordinated so that no overlap exists between the quiet periods. During the first quiet period, the first base station and/or an associated device (such as a CPE served by the first base station) performs in-band sensing to detect wireless devices that use a first frequency or channel also used by the first base station. During the second quiet period, the first base station and/or a coordinate device (such as a CPE served by the first base station and assisting the second base station) performs out-band sensing to detect wireless devices that use a second frequency or channel also used by the second base station.

Abstract: In an embodiment, a channel estimator includes first, second, and third stages. The first stage is configurable to generate a first observation scalar for a first communication path of a first communication channel, and the second stage is configurable to generate a second observation scalar for a first communication path of a second communication channel. And the third stage is configurable to generate channel-estimation coefficients in response to the first and second observation scalars. For example, such a channel estimator may use a recursive algorithm, such as a Vector State Scalar Observation (VSSO) Kalman algorithm, to estimate the responses of channels over which propagate simultaneous orthogonal-frequency-division-multiplexed (OFDM) signals (e.g., MIMO-OFDM signals) that suffer from inter-carrier interference (ICI) due to Doppler spread.

Abstract: In an embodiment, a transmitter includes a transmission path that is configurable to generate first pilot clusters each including a respective first pilot subsymbol in a first cluster position and a respective second pilot subsymbol in a second cluster position such that a vector formed by the first pilot subsymbols is orthogonal to a vector formed by the second pilot subsymbols. For example, where such a transmitter transmits simultaneous orthogonal-frequency-division-multiplexed (OFDM) signals (e.g., MIMO-OFDM signals) over respective channels that may impart inter-carrier interference (ICI) to the signals due to Doppler spread, the pattern of the pilot symbols that compose the pilot clusters may allow a receiver of these signals to estimate the responses of these channels more accurately than conventional receivers.

Abstract: An embodiment of a receiver includes a channel estimator and a data-recovery unit. The channel estimator is configured to determine a characteristic of a channel over which a first signal, which is received simultaneously with a second signal, propagated, the first and second signals respectively having first and second components that include approximately a frequency. And the data-recovery unit is configured to recover data from the first signal in response to the determined channel characteristic. For example, such a receiver may be able to receive simultaneously, and over the same channel space, orthogonal-frequency-division-multiplexed (OFDM) signals that include one or more of the same subcarrier frequencies, and to recover data from one or more of the OFDM signals despite the frequency overlap. A receiver with this capability may allow an increase in the effective bandwidth of the channel space, and thus may allow more devices to simultaneously share the channel space.

Abstract: In an embodiment, a channel estimator includes first and second stages. The first stage is configurable to generate an observation scalar for a communication path of a communication channel, and the second stage is configurable to generate channel-estimation coefficients in response to the first observation scalar. For example, such a channel estimator may use a recursive algorithm, such as a VSSO Kalman algorithm, to estimate the response of a channel over which propagates an OFDM signal that suffers from ICI due to Doppler spread. Such a channel estimator may estimate the channel response more accurately, more efficiently, with a less-complex algorithm, and with less-complex software or circuitry, than conventional channel estimators. Furthermore, such a channel estimator may be able to dynamically account for changes in the number of communication paths that compose the channel, changes in the delays of these paths, and changes in the signal-energy levels of these paths.

Abstract: An embodiment of a transmitter includes detection, generating, and transmission stages. The detection stage is configured to detect a first signal having a first component that includes a frequency, and the generating stage is configured to generate a data component that includes approximately the frequency in response to the detection of the first signal. The transmission stage is configured to transmit a second signal having the data component while the detection stage is detecting the first signal. For example, two or more such transmitters (e.g., two or more smart phones) may simultaneously transmit OFDM signals on the same subcarrier frequencies and over the same channel space. By allowing the simultaneous transmission of multiple signals on the same frequencies and over the same channel space, such a transmitter may increase the effective bandwidth of the channel space, and thus may allow more devices to simultaneously share the same channel space.

Abstract: A system includes a plurality of stations capable of communicating with each other. A station of the system may comprise multiple antenna subassemblies and a receiver coupled to the subassemblies. The station is operable to activate one or more of the subassemblies to determine a direction of a first incoming signal, and to then activate another one or more of the subassemblies to receive a second incoming signal from substantially the same direction. Alternatively, the station may comprise multiple antenna subassemblies and a receiver coupled to the subassemblies and operable to activate each of the subassemblies for a respective interval to service at least one respective transmitting station covered by the activated subassembly during the interval.

Abstract: In an embodiment, a channel estimator includes first and second stages. The first stage is operable to generate a respective one-dimensional array of first channel-estimation coefficients for each communication path of a communication channel, and the second stage is operable to generate a multi-dimensional array of second channel-estimation coefficients in response to the first channel-estimation coefficients. For example, such a channel estimator may estimate the response of a channel over which propagates an orthogonal-frequency-division-multiplexed (OFDM) signal that suffers from inter-carrier interference (ICI) due to Doppler spread. Such a channel estimator may estimate the channel response more efficiently, and with a simpler algorithm, than conventional channel estimators.

Abstract: A method and apparatus for conserving power in a wireless communication device. The method includes receiving at least a portion of a PHY protocol data unit (PPDU) frame, where the PPDU frame includes an aggregate MAC protocol data unit (A-MPDU) field. The method also includes comparing a receiver address (RA) within the A-MPDU field to a stored address of the wireless communication device and, if the received RA does not match the stored address, causing power to be removed from one or more circuits of the wireless communication device for a calculated period of time.

Abstract: A method and apparatus for negotiating an idle subchannel set for a wireless data transmission. The method includes transmitting an indication of a first set of idle subchannels to a wireless station. The method also includes receiving an indication of a second set of idle subchannels from the wireless station. The method further includes determining a final set of idle subchannels based on the indication of the first set of idle subchannels and the indication of the second set of idle subchannels.

Abstract: TDLS support in VHT devices is enabled through the use of added VHT fields in the TDLS frames. A VHT TDLS direct link can be setup through a respective TDLS Setup Request/Response with added field announcing VHT Capabilities of the VHT device and the peer device. Added VHT Operation field in the TDLS Setup Confirm frame adds supports between VHT peer devices for non-VHT BSS and VHT BSS. Two VHT STAs can establish wider TDLS channel than BSS operating channel through TDLS establishment. VHT off channel support is enabled by adding Wide Bandwidth Channel Switch field in the TDLS Channel Switch Request frame and no changes to TDLS Channel Switch Response. A VHT Capabilities field is also added to TDLS Discovery Response frame to inform peer devices of device capabilities.

Abstract: Radio frequency (RF) architectures for spectrum access networks are provided. Embodiments of the invention generally provide a radio frequency (RF) architecture for customer premise equipment (CPE) for use in, for example, IEEE 802.22 wireless regional area networks (WRANs). In some embodiments, the CPE RF architecture includes two receive chains with a directional antenna and an omni-directional antenna, respectively. The CPE RF architecture facilitates opportunistic out-of-band spectrum sensing and WRAN signal receiving that are performed in parallel with data transmission.