Motion detection and localization based on bi-directional channel sounding

A non-transitory computer-readable medium comprising instructions which, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• obtaining first and second sets of channel information based on first and second sets of wireless signals transmitted bi-directionally through a space between a first device and a second device during a timeframe,
• wherein the first set of channel information is based on the first set of wireless signals transmitted to the first device from the second device,
• and the second set of channel information is based on the second set of wireless signals transmitted to the second device from the first device;
• comparing a first channel variation indicated by the first set of channel information with a second channel variation indicated by the second set of channel information, wherein the comparison analyzes similarity of the first and second channel variations;
• and
• based on the comparison, detecting a category of motion or a location of detected motion in the space during the timeframe.

A system comprising:

• a plurality of wireless communication devices comprising a first wireless communication device and a second wireless communication device;
• data processing apparatus;
• memory storing instructions that are operable when executed by the data processing apparatus to perform operations comprising:
• obtaining first and second sets of channel information based on first and second sets of wireless signals transmitted bi-directionally through a space between the first and second wireless communication devices during a timeframe,
• wherein the first set of channel information is based on the first set of wireless signals transmitted to the first wireless communication device from the second wireless communication device,
• and the second set of channel information is based on the second set of wireless signals transmitted to the second wireless communication device from the first wireless communication device;
• comparing a first channel variation indicated by the first set of channel information with a second channel variation indicated by the second set of channel information, wherein the comparison analyzes similarity of the first and second channel variations;
• and
• based on the comparison, detecting a category of motion or a location of detected motion in the space during the timeframe.