Facebook, Inc.

Yan Yan

Abhishek Tiwari

Pratheep Bondalapati

Sam Padinjaremannil Alex

Qi Qu

Hongyu Zhou

Ali Yazdan Panah

Tobias Gerard Tiecke

Ali Yazdan

Chiyun Xia

Qi Tang

Apparatuses, methods, and systems for MIMO inter-stream interference cancellation are disclosed. One method includes determining a channel matrix between a plurality of transmitting antennas of a transmitter and a plurality of receiving antennas of a receiver, determining a plurality of channel propagation delays based on a propagation delay between each of the plurality of transmitting antennas and each of the plurality of receiving antennas, determining differences in the plurality of channel propagation delays, preprocessing, by the transmitter, streams of symbols for each transmitting antenna for transmission based on the differences in the plurality of channel propagation delays and based on the channel matrix, and transmitting, by the transmitter, the preprocessed symbol streams through the plurality of transmitting antennas.

MIMO (multiple-input, multiple-output) inter-stream interference cancellation

Apparatuses, methods, and systems for MIMO inter-stream interference cancellation are disclosed. One method includes determining a channel matrix between a plurality of transmitting antennas of a transmitter and a plurality of receiving antennas of a receiver, determining a plurality of channel propagation delays based on a propagation delay between each of the plurality of transmitting antennas and each of the plurality of receiving antennas, preprocessing, by the transmitter, streams of symbols for each transmitting antenna for transmission based on the plurality of channel propagation delays and based on the channel matrix, and transmitting, by the transmitter, the preprocessed symbol streams through the plurality of transmitting antennas.

Apparatuses, methods, and systems for analog spatial multiplexing are disclosed. One apparatus includes a receiver, wherein the receiver includes a plurality of antennas operative to receive a plurality of wireless signals, a plurality of tunable time delays, and a plurality of frequency response equalizers, wherein a time delay of each of the tunable time delays is adjusted based on a feedback of measurements of one or more pilot tones of more than one output of the plurality of frequency response equalizers. The receiver further includes a plurality of frequency up-converters generating a plurality of frequency up-converted signals, a MIMO processor receiving the plurality of frequency up-converted signals, wherein the MIMO processor adjusts a gain and phase of the of the frequency up-converted signals based on the measurements of the pilot tones, and a plurality of frequency down-converters receiving and frequency down-converting output signals from the MIMO processor.

Modem-agnostic analog spatial multiplexing

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Culver City, CA, United States of America

Yan Yan