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seemoo-lab / nexmon_csi

Channel State Information Extraction on Various Broadcom Wi-Fi Chips
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Can the Asus ac86u be used as transmitter to measure angle of departure？ #210

Open zel602 opened 3 years ago

zel602 commented 3 years ago

Thanks to everyone's help，I understand a spatial stream will be transmitted from more than one antennas.

May I ask anonther question, Can I use the Asus ac86u as transmitter to measure angle of departure？

I know the premise of the question is that the positional relative relation of the spatial streams is known, is it possible to obtain this prior knowledge?

yujianyuanhaha commented 3 years ago

@zel602 It is possible to measure the angles between a pair of transmitter and receiver router using SpotFy.

zel602 commented 3 years ago

@yujianyuanhaha thanks for your answer！But I care about how to capture the valid data to obtain angle of departure, rather than the theory.

quantumhub commented 3 years ago

More effort is needed to make this tool useful. The agc and lna status associated with CSI have to be extracted (but not yet provided by this tool). Otherwise, it can't be used for aoa. For aod, preceding matrix has to be fixed. But now, it is in wild status. @yujianyuanhaha @zel602

zel602 commented 3 years ago

@quantumhub Thank you for your answer！ It is really helpful！

yujianyuanhaha commented 3 years ago

@quantumhub I assume AoA can be estimated using the SpotFy. AGC and LNA can be skipped.

quantumhub commented 3 years ago

Spotfi is based on Intel 5300 NIC card. I have not tried this card. Intel 5300's CSI extraction ucode implementation is proprietorial, unlike Atheros ath9k CSI or Nexmon Bcm here. Maybe Intel's proprietorial implementation has compensate lna and agc's impact. Or they have fixed lna and agc's gain level. @yujianyuanhaha