Facts about CSI Phase Measured by Atheros 9300 NIC

Facts, The Verified Facts...

In this short page, several verified facts about CSI phase information are listed. More is pending, and discussions are welcome. 1. 0-th subcarrier of the 1st antenna, the most dominating. 0-th Subcarrier CSI phase measurement contains several noises/errors: CFO (Carrier Frequency Offset), SFO (Sampling Frequency Offset), PDD (Packet Detection Delay), and random initial phase, etc. Their impacts to OFDM CSI is different. SFO and PDD cause phase rotation (or slope component across subcarriers); CFO and random initial phase together cause random-like overall phase shift (or intercept component). [Read More]

PicoScenes: Get Started

Basic CSI Measurement Guide

This tutorial will guide you how to perform CSI measurement using PicoScenes. Major Steps Kernel and PicoScenes Installation Install PicoScenes MATLAB Toolbox Prepare NICs for CSI Logging Prepare PicoScenes Argument Text File Perform CSI Measurement using PicoScenes Parse .csi Files using PicoScenes MATLAB Toolbox Recover Normal Wi-Fi Mode Step 1:Kernel And PicoScenes Installation Follow the installation tutorial https://gitlab.com/wifisensing/platform-setup/ Step 2: Install PicoScenes MATLAB Toolbox Click https://gitlab.com/wifisensing/release/matlab-toolbox-release , then click the Download button (cloud with downward arrow icon), and choose picoscenes-matlab-toolbox. [Read More]

TechNote: Subcarrier Occupation in 802.11n HT20, HT40 and HT40+/- Channel Modes

Use HT20 or HT40 Mode!

Section 20.3.7 in 802.11n Standard states clearly about the subcarrier occupation in HT20/HT40/HT40+/HT40- channel mode: … In the 20 MHz HT format, the signal is transmitted on subcarriers –28 to –1 and 1 to 28. In the case of the 40 MHz HT format, a 40 MHz channel is used. The channel is divided into 128 subcarriers. The signal is transmitted on subcarriers –58 to –2 and 2 to 58. [Read More]