Clarification Request on Your Work in openwifi CSI fuzzer for authorized sensing and covert channels

[GaryGogh]

Dear Professor Xianjun Jiao,

I hope this issue finds you well. I am reaching out to you with a deep interest in the innovative work you have contributed to in the field of wireless communication, particularly regarding the openwifi project. Your research has been a source of inspiration and learning for many in the academic community.

Recently, while reading a paper by Professor Luo Jun titled "MIMOCrypt: Multi-User Privacy-Preserving Wi-Fi Sensing via MIMO Encryption," I encountered a reference to your work. In this paper, it is mentioned that "Jiao et al. [27] leverages a secret switching sequence among a set of pre-defined LTSs to perform scrambling upon sm. Such a solution is hard to achieve in the real world because LTS is fixed in the digital circuit of a Wi-Fi NIC; it can be altered in [27] only thanks to the adoption of customized hardware. Also, the binary pattern of LTS offers very little scrambling space."

However, upon reviewing your paper, “Openwifi CSI fuzzer for authorized sensing and covert channels,” I understand that the approach actually involves introducing a digital filter at the transmitter for CSI obfuscation, rather than altering the Long Training Sequence (LTS). This observation has led to some confusion on my part regarding the relationship, if any, between the LTS and the digital filter techniques in your work.

Could you kindly provide some clarity on this matter? Specifically, I am interested in understanding whether there is a connection or overlap between the use of LTS and digital filters in the context of your research in openwifi. Your insights would be invaluable in enhancing my understanding of these sophisticated techniques.

Thank you very much for your time and for your groundbreaking contributions to the field. I look forward to your response and to learning more from your work.

PS: Additionally, I was wondering how to configure openwifi for simultaneous dual-antenna transmission. Could you provide some guidance on this? Thank you!

Best regards,

Gary