Abstract: Various embodiments enable a multi-active mobile communication device to mitigate (manage) interference by a frequency band used by a first subscription with the frequency band used by a second subscription. The device processor may generate modified power measurements for one or more frequency bands of a first subscription and use the modified power measurement(s) to cause the first subscription to switch from the frequency band that interferes with the frequency band of the second subscription. The modified power measurement may be a decreased power measurement of the first frequency band and/or an increased power measurement of a second frequency band that does not interfere with the frequency band of the second subscription. As a result, various embodiments may mitigate or otherwise manage the impact of coexistence interference between the first and second subscriptions of a multi-active mobile communication device without limiting capabilities of the device or changes to the network.

Abstract: The present disclosure includes systems and methods for operating a wireless communication system in multiple modes. The system is configured in a first mode when a transmission interference in a receiver of a wireless device is below a first threshold. The system is configured in one or more intermediate modes when the transmission interference is above the first threshold and below a second threshold. The system is configured in a second mode when the transmission interference is above the second threshold. The one or more intermediate modes activate interference management processes and the wireless device transmits data and receives data simultaneously. In some embodiments, transmission interference may be based on an SINR measurement.

Abstract: Methods and apparatus for timing synchronization based on transitional pilot symbols. In an aspect, a method is provided for time tracking synchronization in an OFDM system. The method includes receiving at least one TDM pilot symbol comprising a plurality of modulated sub-carriers that are configured to provide a channel estimate having a length that extends up to a duration of an FFT used for data transmission. The method also includes determining one or both of an instantaneous and averaged channel estimates from the plurality of modulated sub-carriers, and calculating a timing offset based on one or both of the channel estimates. An apparatus includes a receiver configured to receive the at least one TDM pilot symbol, a channel estimator configured to determine the instantaneous and averaged channel estimates, and a time synchronizer configured to calculate a timing offset based on the channel estimates.

Abstract: Optimizing multiflow performance and priority across UEs and networks including receive antenna selection at the UEs, CSI measurement and reporting, and scheduling for multiflow operation. The techniques may evaluate channel conditions for a UE for multiple access points and different combinations of antennas and determine how the UE should feedback CSI for transmissions from the multiple access points. The disclosed techniques also include techniques for scheduling transmissions from the multiple access points using the CSI information to optimize multiflow performance and priority across UEs and networks. Various scheduling modes use feedback from UEs including the maximum supported rates for each link and/or rates based on the maximum sum capacity of the links used concurrently. The scheduler may maintain separate priority lists for each access point or a single priority list across both access points. The techniques may be used for multiflow operation using LTE and WLAN links.

Abstract: A user equipment (UE) may reduce coexistence issues with one or more radio access technologies (RATs) caused by a bursty interference. The bursty interference may be detected by detecting a number of modes in a measured signal sample and determining when a signal contains a multi-modal distribution based at least in part on the detecting. A coexistence indication is created based at least in part on the determining.

Abstract: Methods and apparatus for RF handoff in a multi-frequency network. A method includes detecting a mobility event associated with a detection of a new wide area operating infrastructure (WOI), updating a current WOI identifier to a new WOI identifier, acquiring control channel information associated with the new WOI identifier, determining if an active registered flow list has been updated based on the control channel information, and performing an acquisition procedure to acquire one or more registered flows if it is determined that the active registered flow list has been updated. Another method includes detecting a mobility event associated with a detection of a new local area operating infrastructure (LOI), updating a current LOI identifier to a new LOI identifier, acquiring control channel information, determining if an active registered flow list has been updated, and performing an acquisition procedure to acquire one or more registered flows.

Abstract: Dynamic adjustment of antenna selection period at a wireless communication device or user equipment having two or more antennas. The described approaches consider an antenna selection performance metric. The antenna selection performance metric may include both measurement overhead (capacity loss due to measurements) and antenna switching capacity gain (gain in capacity through switching antenna subsets). The antenna selection performance metric may further include an estimate of UE speed or an antenna selection change rate. The antenna selection period may be adjusted by increasing or decreasing the antenna selection period based on the antenna selection performance metric. Antenna selection may be enabled or disabled based on the antenna selection performance metric.

Abstract: Systems and methods are provided for enhancing signal quality at receivers in a wireless network. In one embodiment, an antenna is selected from a subset of antennas based on a signal quality parameter such as received signal power or signal-to-noise ratio (SNR). In another embodiment, multiple antennas are applied to independent signal processing paths for the respective antennas where output from the paths is then combined to enhance overall signal quality at the receiver.

Abstract: A user equipment (UE) may manage coexistence between multiple radio access technologies (RATs) utilized by the UE to allow a first RAT to be active during times when communications of a second RAT of the UE are inactive. In some instances, the UE may indicate discontinuous reception (DRX) operation of the UE to allow for time-division multiplexed (TDM) operation between the first RAT and the second RAT. The UE may set a hybrid automatic repeat request (HARQ) configuration to allow for a HARQ retransmission of a packet of the first RAT, originally received in a first DRX cycle, during a second DRX cycle.

Abstract: In a user equipment (UE) with multiple radio access technologies (RATs), communications of one RAT engaged in connection setup may be protected from communications of other RATs. Techniques for protecting such connection setups include performing power backoff on a potentially interfering RAT or implementing a time division multiplexing (TDM) solution alternating when certain RATs are active.

Abstract: For channel estimation in a spectrally shaped wireless communication system, an initial frequency response estimate is obtained for a first set of P uniformly spaced subbands (1) based on pilot symbols received on a second set of subbands used for pilot transmission and (2) using extrapolation and/or interpolation, where P is a power of two. A channel impulse response estimate is obtained by performing a P-point IFFT on the initial frequency response estimate. A final frequency response estimate for N total subbands is derived by (1) setting low quality taps for the channel impulse response estimate to zero, (2) zero-padding the channel impulse response estimate to length N, and (3) performing an N-point FFT on the zero-padded channel impulse response estimate. The channel frequency/impulse response estimate may be filtered to obtain a higher quality channel estimate.

Abstract: To comport with specific absorption rate (SAR) requirements for a transmitting multi-radio mobile device, transmissions of the multiple radios may be duplexed to ensure compliance with communication regulations. Duplexing of transmissions may occur if overall transmissions exceed a particular threshold value. The duplexing may be opportunistic or deterministic.

Abstract: A method of wireless communication includes determining denial rates for first and second communication attempts of a packet using a first communication resource (e.g., an LTE radio). The method also includes allowing a second communication resource (e.g., a Bluetooth radio) to communicate when communication attempts from the first communication resource are denied. The denial rates are chosen to achieve threshold levels of performance for the first and second communication resources. The second denial rate may be set and the first denial rate adjusted in a looped manner to achieve desired Bluetooth performance. The denial rates may be set to deny all first communication attempts but to allow all second communication attempts. Final attempts to transmit Bluetooth packets may be given priority regardless of the first and second denial rates.

Abstract: Systems and methodologies are described herein that facilitate resolution between respective radios associated with a multi-radio wireless device. As described herein, various techniques can be utilized with a multi-radio coexistence manager and/or other suitable mechanisms associated with a wireless device to perform joint resolution for multiple associated radios, thereby providing performance enhancements over conventional piecewise radio resolution schemes. Various exhaustive, decoupled, and progressive radio resolution algorithms are provided herein, by which respective sets of parameters (e.g., transmit powers, interference targets, frequency sub-bands, radio frequency knob settings, etc.) can be selected for respective potentially conflicting radios to enable such radios to operate in coexistence. Further, techniques are provided herein for utilizing a graph theoretic algorithm for progressive radio resolution.

Abstract: A method for wireless communication modifies an actual buffer status report value to create a modified buffer status report that is reported to a base station. The modified buffer status report value results in the base station sending fewer uplink grants to a user equipment. The fewer grants result in transmission gaps in a first radio access technology of the user equipment. The user equipment may use those transmission gaps in the first radio access technology to communicate using a second radio access technology.

Abstract: A method for mitigating the impact of a power imbalance on a remote data rate in a wireless local area network (WLAN) includes transmitting a wireless local area network (WLAN) acknowledgement (ACK) packet at a first transmit power level to a remote device. The method further includes transmitting, to the remote device, a WLAN data packet at a second transmit power level that is lower than the first transmit power level of the WLAN ACK packet. Another method for mitigating the impact of a power imbalance on a remote data rate in a wireless local area network (WLAN) may include selecting a wireless local area network (WLAN) acknowledgement (ACK) packet transmit rate independent from a rate at which a WLAN data packet is received. This method further includes transmitting, to a remote device, a WLAN ACK packet at the selected WLAN ACK packet transmit rate.

Abstract: Certain aspects of the present disclosure relate to methods and apparatus for adaptive antenna management in LTE. Devices and networks capable of transmitting and receiving signals using a variable number of transmitting or receiving antennas using LTE radio access technology are described.

Abstract: Methods and apparatus for signaling parameter distribution for neighboring radio frequencies. A method includes identifying selected local operations infrastructures (LOIs) and one or more neighboring LOIs, generating a neighbor description message (NDM) that identifies the selected LOIs and their respective neighbors and specifies SP information for each RF channel associated with the selected LOIs and their respective neighbors, and distributing the NDM over each of the selected LOIs. An apparatus includes a message decoder configured to receive a NDM that identifies RF channels associated with selected LOIs and one or more neighboring LOIs, wherein each RF channel is associated with SP information, and processing logic configured to receive a request to obtain selected SP information associated with a selected RF channel, determine the selected SP information associated with the selected RF channel based on the NDM, and output the selected SP information.

Abstract: Interference between potentially conflicting radio access technologies (RATs) in a wireless device may be managed through a coexistence manager which allows communication using a first active RAT (e.g., Long Term Evolution (LTE)) and communication with a second active RAT (e.g., wireless local area network (WLAN)) when the first RAT is not scheduled for communicating during an uplink timeslot. Communications by a WLAN radio may be controlled using a power save mode. WLAN communications may be timed so that downlink signals (such as data or acknowledgement messages) to the WLAN radio are received during an inactive uplink subframe for an LTE radio. WLAN communications may also be timed so that downlink signals to the WLAN radio are received during downlink times scheduled for an LTE radio.

Abstract: Methods and apparatus for service acquisition in a multi-frequency network. In an aspect, a method is provided for service acquisition in a multi-frequency network. The method includes detecting a service acquisition trigger event and identifying a selected RF channel from an acquisition RF list based on signal strength, wherein the acquisition RF list identifies RF channels in one or more local operations infrastructures (LOIs) of the multi-frequency network. The method also includes acquiring a wide system on the selected RF channel, removing the selected RF channel from the acquisition RF list if the wide system can not be acquired on the selected RF channel, and repeating said operations of identifying, acquiring and removing until the wide system is acquired on the selected RF channel or a system acquisition timeout occurs.