Qualcomm Incorporated

Samsung Electronics Co., Ltd.

Insoo Hwang

Bongyong Song

Cong Nguyen

Samir Salib Soliman

Jungwon Lee

Soumya Das

Inyup Kang

Kaushik Chakraborty

Ajay Gupta

Heejin Roh

Samel Celebi

Peter David Heidmann

Huey Trando

Osvaldo Alcala

Won-ick Lee

In one or more access points of a wireless communication network, a method for participating in a distributed clustering process directed at defining clusters of access points wherein each of the clusters comprises a cluster head and associated member nodes includes determining a marginal cost of associating an access point to each of distinct clusters of access points, based on a defined cost function, and associating the access point to one of the clusters of APs for which the marginal cost is minimized. The method may be performed by multiple access points in a peer-to-peer fashion and iterated until a stable cluster configuration is obtained. A cluster head may similarly be appointed in a distributed fashion by a current cluster head comparing total cost functions between different cluster configurations with different cluster heads.

Distributed clustering of wireless network nodes

Aspects of the disclosure are directed to interference cancellation. A method for performing interference cancellation in a wireless communications device having a transmitter, a receiver, a coefficient controller, an analog interference cancellation (AIC) circuit and a receive local oscillator (LO) includes utilizing a receive local oscillator (LO) to generate a transmit pilot; injecting the transmit pilot into a transmit chain for transmission; utilizing a receiver to receive a signal, wherein the signal includes the transmit pilot and an interference signal; and determining a set of coefficients for the interference cancellation based on an output signal from the receiver.

Pilot-based analog active interference canceller

Aspects of the disclosure are directed to interference cancellation and wireless communication. A method of performing analog interference cancellation in a wireless communications device having a transmitter and a receiver includes receiving a reference signal representative of an interfering signal transmitted by the transmitter, selecting a first target interference type from one of a plurality of interference types affecting a an RF signal received by the receiver, configuring a first filter of an interference cancellation circuit using a coefficient computed based on the first target interference type, and cancelling interference in the RF signal using an output of the first filter. Coefficient computation may be performed in a switched manner between analog and digital domain, simultaneously in multiple domains, or in a cascaded manner that provides digital interference cancellation.

Switched, simultaneous and cascaded interference cancellation

A method of operation of a mobile telecommunication system includes: measuring a received reference signal; removing a guard portion from the received reference signal; determining a noise variance estimate from both a noise region of the received reference signal and a noise sample in a signal region of the received reference signal, or calculating a dispersion power of a noise region of the received reference signal and determining the noise variance estimate based on at least a dispersion power; and calculating a signal to noise ratio from the noise variance estimate for adjusting a receiver device.

Mobile telecommunication system with noise ratio estimation mechanism and method of operation thereof

Aspects of the disclosure are directed to interference cancellation. A method of performing interference cancellation in a wireless device having a receiver, a coefficient controller and an analog interference cancellation (AIC) circuit includes utilizing the receiver to receive a signal; utilizing the coefficient controller to compute a first cost function value using a first set of coefficients, to compute a second set of coefficients using a first coefficient control algorithm, to compute a second cost function value using the second set of coefficients, to compare the second cost function value with the first cost function value, and to determine whether to apply the first set or the second set of coefficients based on the comparison; and utilizing the AIC circuit to apply the first or second set of coefficients to filter a reference signal and the receiver to subtract the filtered reference signal from the received signal for interference cancellation.

Robust coefficient computation for analog interference cancellation

Aspects of the disclosure are directed to interference cancellation. A method of performing interference cancellation in a wireless communications device having a transmitter, a receiver, a coefficient controller and an analog interference cancellation (AIC) circuit includes utilizing the receiver for receiving a signal, wherein the received signal includes an interference signal within a spectral region; measuring the received signal to obtain a measurement of the interference signal within a guard region of the spectral region; and determining a set of coefficients based on the measurement of the interference signal within the guard region.

Robust active self-interference cancellation in the presence of external in-band signals using guard region signal measurements

Methods in a multiple-cell cellular network that implements iterative coordinated beamforming (I-CBF) algorithms with limited cooperation from adjacent nodes (base stations and/or mobile stations) may jointly determine transmit beamforming vectors and receive combining vectors to increase sum throughput. The transmit beamforming vectors and receive combining vectors can be determined based on a performance metric, such as by maximizing SINR (signal-to-interference-and-noise ratio) for each mobile station in the network, maximizing SLNR (signal-to-leakage-and-noise ratio) for each base station in the network, or minimizing SMSE (sum mean square error). The algorithms may be performed to update vectors synchronously. In other cases, the algorithms may be performed to update vectors asynchronously.

Iterative coordinated beamforming systems and methods

Aspects of the present disclosure are directed to apparatuses and methods that can improve Bluetooth (BT) and Wireless Local Area Network (WLAN) coexistence at a BT/WLAN co-located wireless communication device. Various coexistence schemes are provided such as dynamic WLAN fragmentation based on high priority BT traffic by utilizing various techniques and signaling schemes. In some aspects of the disclosure, narrow-band active interference cancellation may be combined with dynamic WLAN fragmentation to further improve BT/WLAN coexistence performance.

Apparatus and methods of bluetooth and wireless local area network coexistence

A device may use enhanced power amplifier (PA) linearization techniques such as adaptive feed-forward (FF) linearization using adaptive filters. In one example, an adaptive feed-forward linearizer may isolate a distortion signal based at least in part on the signals input to and output from a PA in a transmission path. The distortion signal may be used to cancel distortion at the output of the PA to produce an improved output signal. A first adaptive circuit may be used to produce the distortion signal and a second adaptive circuit may be used to produce an error cancellation signal based at least in part on the distortion signal. The error cancellation signal may be amplified and re-introduced to the transmission path to produce the improved output signal. Semi-adaptive circuits may be used in place of the adaptive circuits, or a hybrid approach may be used.

Adaptive feed-forward power amplifier linearization methods using adaptive filters

Techniques for compensating for self-induced interference in a small cell base station are provided. The techniques include detecting control signals from a neighboring base station associated with a wireless communication network, the control signals being transmitted by the neighboring base station at predetermined intervals, and compensating for self-induced interference caused by a transmitter of the small cell base station transmitting during the predetermined intervals in which control signals are received from the neighboring base station and the transmitter of the small cell base station is transmitting data.

Avoiding suspended transmission during network listen for small cell base stations

Aspects of the disclosure are directed to interference cancellation. A method of performing interference cancellation in a wireless communications device having one or more transmit antennas, one or more transmitters, one or more receive antennas, one or more receivers, one or more coefficient controllers and one or more analog interference cancellation (AIC) circuits includes using the one or more coefficient controllers for determining coefficients for one or more adaptive filters within the one or more AIC circuits.

Radio frequency (RF) analog interference cancellation (AIC) with multiple antennas

A method of performing interference cancellation (IC) in a wireless communication device having a receiver comprising at least a primary receiver chain and a diversity receiver chain includes determining an interference level of a transmitted signal on the receiver; determining whether the interference level is within a predetermined range; selecting a first mode of operation if the interference level is within a predetermined range; and selecting a second mode of operation if the interference level is not within the predetermined range. The first mode includes receiving, at the primary receiver chain, a first signal corresponding to the transmitted signal; receiving, at the diversity receiver chain, a second signal corresponding to the transmitted signal for providing to an IC circuit; generating, at the IC circuit, an output signal based on the second signal; and generating a cancellation signal based on the output signal and the first signal.

Opportunistic active interference cancellation using RX diversity antenna

A method of operation of a communication system includes: estimating a channel; calculating a predicted signal within the channel; evaluating a prediction accuracy of the predicted signal; and adjusting a handoff parameter when the prediction accuracy of the predicted signal is within a threshold range for communicating through a mobile station.

Communication system with adaptive handover controller and method of operation thereof

Aspects of the disclosure are directed to interference cancellation and wireless communication including determining the strength of a reference signal; comparing the strength of the reference signal to a first threshold and a second threshold; and performing one of the following: updating at least one coefficient if the strength of the reference signal is above the first threshold; freezing the at least one coefficient if the strength of the reference signal is between the first threshold and the second threshold; or setting an interference cancelation (IC) circuit to OFF if the strength of the reference signal is below both the first threshold and the second threshold.

Multi-layer coefficient control for dynamic interference cancellation

A method of operation of a mobile telecommunication system includes: measuring a measured target power and a measured server power; predicting a future target power and a future server power for a prediction tap number from when the measured target power and the measured server power are measured; computing an estimation error and a prediction error associated with the future target power and the future server power; determining a handoff hysteresis level based on the estimation error and the prediction error; and sending a handoff trigger for transferring a mobile station from a server station to a target station when the future target power minus both the future server power and the handoff hysteresis level is greater than zero.

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San Diego, CA, United States of America

Insoo Hwang