Efficient channel estimation for implicit mu-mimo

Abstract

Base station for MIMO wireless systems implementing efficient channel estimation techniques. An illustrative embodiment includes: an array of multiple antennas for exchanging uplink and downlink signals with spatially distributed user terminals; a plurality of: transmission chains, each coupled to the multiple one of the antennas, the transceiver further coupling the antenna to a corresponding one of the plurality of receive chains; and a controller, each of the receive chains opportunistically deriving from the wireless uplink signal The packet header derives estimated uplink channel response coefficients, and the controller determines the steering transform based at least in part on the estimated channel response coefficients. The transmit chain applies a steering transformation to the spatially distinct downlink signals to produce antenna-specific downlink signals for each antenna in the array. Another illustrative embodiment determines a mobility indicator for each user terminal based at least in part on the estimated channel response coefficients, and schedules at least one action based on the mobility indicator.

Description

[0001] Cross References to Related Applications [0002] This application claims Provisional U.S. Application 62 / , entitled "Efficient Channel Estimation for Implicit MU-MIMO" and filed August 25, 2016, named inventors Ryan E. Guerra, Clayton W. Shepard, Narendra Anand, Edward Knightly, and Lin Zhong 379,351 priority. [0003] Government Support Recognition [0004] This invention was made with government support under one or more contracts awarded by the National Science Foundation (Contract Nos. 1126478, 1218700, 1405937, 1444056, 1514285, 1518916, and / or 1520496). The government has certain rights in this invention. Background technique [0005] Wireless networks have become ubiquitous, enabling a wide variety of electronic devices to communicate wirelessly with each other and to access the Internet. The number of devices and their respective bandwidth requirements continue to increase, prompting engineers to develop new communication technologies to utilize the availabl...

AI Technical Summary

Problems solved by technology

The CSI measurement process for MU-MIMO systems can be implemented in various ways, but the existing MU-MIMO CSI measurement process requires a portion of the channel bandwidth to be allocated as a fixed overhead for CSI measurement

As provided in the existing IEEE 802.11af standard, the required overhead allocation increases with the number of user terminal antennas K grows proportionally (and in one implementation, also with the number of base station antennas M grows proportionally), and in at least some cases the overhead approaches 90% of the available channel bandwidth, severely limiting data throughput

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