Qualcomm Incorporated

Sunil Kumar Kandukuri Narayana

Hemanth Sampath

Sameer Vermani

Shivratna Giri Srinivasan

Raghu Narayan Challa

Brian Clarke Banister

Michael Lee McCloud

Stefan Brueck

Matthias Brehler

Chengjin Zhang

Brian George

Remi Jonathan Gurski

The present disclosure relates to resolving out-of-sync uplink grants for communication in an unlicensed spectrum. For example, a user equipment (UE) may receive an uplink grant from a network entity on a downlink communication channel, wherein the uplink grant is associated with a system frame number (SFN). The UE may further determine, based on the SFN, that the uplink grant is out of order with one or more stored uplink grants within a queue. Additionally, the UE may insert the uplink grant in an ordered position within the queue relative to the one or more stored uplink grants.

Out-of-sync grant handling in a wireless communication system

Methods and apparatus for correcting frequency errors between a carrier frequency of a signal received by a wireless device and a reference frequency local to the device. For certain aspects, such a method generally includes receiving a signal in a receiver having an LO producing a reference frequency, a radio frequency (RF) phase-locked loop (PLL), and a digital rotator, estimating a frequency difference between a carrier frequency of the received signal and the LO reference frequency, and applying the estimated frequency difference to the RF PLL and the digital rotator.

Dual frequency tracking loop for OFDMA systems

Techniques for performing time tracking in a communication system utilizing a cyclic prefix are described. In an aspect, a receiver may detect for large timing errors based on early and late received samples obtained with early and late FFT windows, respectively. The receiver may derive first and second channel impulse response (CIR) estimates based on the early and late received samples, respectively, determine an early channel energy based on the first CIR estimate, determine a late channel energy based on the second CIR estimate, compute an update amount based on the early and late channel energies, and update the FFT window position based on the update amount. In another aspect, the receiver may perform time tracking with an inner time tracking loop (TTL) and an outer TTL. The receiver may update the FFT window position in coarse steps with the outer TTL and in fine steps with the inner TTL.

Time tracking loops for a communication system utilizing a cyclic prefix

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San Diego, CA, United States of America

Sunil Kumar Kandukuri Narayana