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]