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RikeshMMM / ESP32-CSI-Python-Parser

This is a Python parser for ESP32 Wi-Fi Channel State Information (CSI) based on the ESP32 CSI specification.
MIT License
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relation between |z| formula with amplitude #3

Open syahirseth opened 2 years ago

syahirseth commented 2 years ago

Hi, i am an undergrad student doing a project using the CSI Toolkit and your CSI Parser. I have a question, how do you relate between the amplitude calculation and the modulus z formula from link below https://farside.ph.utexas.edu/teaching/315/Waveshtml/node88.html Capturedth l

RikeshMMM commented 2 years ago

Note: Use light theme to see equations and diagrams.

Hello syahirseth,

The CSI data represents the amplitude and phase of the signal as a complex number mathematically written as,

is a complex number where the symbol represents the square root of minus one i.e.

and are real numbers. (the 2nd byte of CSI pair) being the real part and (the 1st byte of CSI pair) being the imaginary part of the complex number.

img3137

The complex number can be visualised by plotting the coordinates of the imaginary and real part of the number.

In this case we are interested to calculate . This is the distance of point from 0 regardless of the direction (magnitude).

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