Actively seeking faculty positions

Sijie Ji

Schmidt Science Fellow | Caltech

Building sensing-driven physical AI systems to decode real-world human states and drive proactive interventions.

I develop Physical AI for human-centered cyber-physical systems, focusing on how intelligent systems can reliably infer latent human states from imperfect real-world observations and act under uncertainty and resource constraints.

My work spans mobile, wearable, and wireless sensing and integrates learning with system-level design for dependable real-world operation. I work with Prof. Wei Gao and Prof. Mani Srivastava.

By bridging the gap between hardware constraints and algorithmic robustness, I aim to transform healthcare from episodic clinic-centered care into continuous support embedded in daily life.

Get in Touch Google Scholar

Physical AI Cyber-Physical Systems Mobile & Ubiquitous Computing Sensing + X AI + Health

News

[6/26] Gave an invited talk at the NSF Athena AI Institute's Athena Seminar Series at Duke University.
[5/26] Our paper has been accepted in principle by Nature Sensors. Congratulations to all collaborators!
[4/26] Our work on Spiking Neural Networks for mmWave Sensing has been accepted to ICML. Congrats to the team!
[4/26] We are co-organizing the HumanSys and MobiDx workshops at MobiCom 2026. We warmly welcome submissions!
[3/26] Selected as NIH mHealth Training Institute Scholar
[2/26] Our work, AquaCode, which turns transaction platforms into non-invasive liquid quality checkers, is accepted to MobiSys 2026!
[1/26] Papers are accepted by IEEE TMC & ICASSP 2026. Congrats to the team!
[1/26] Give a guest lecture, CSE 5360 Artificial Intelligence (Graduate-level), at the University of Texas at Arlington.
[11/25] Invited to serve as TPC member of EMSOFT 2026.
[09/25] GSRF is accepted by NeurIPS 2025 as a spotlight (~3.19%). Congrats to Kang! See you in SD!
[07/25] Papers are accepted by IEEE TMC & ACM MM. Congrats to Xinzhe and Sheng!
[06/25] Invited to serve as TPC member of Sensys 2026. Welcome to submit papers!
[05/25] LLM + Mental Health papers are accepted by SenSys (poster), ACL 2025. Congrats to the team!
[05/25] Invited to serve as TPC member of MobiCom Demo, MobiCom Poster and BodySys 2025.

[04/25] Invited to serve as a co-Chair for BuildSys 2025.

[04/25] Papers accepted to ACM IMWUT / Ubicomp, IEEE Comm Mag, ICC. Congrats to Luca, Senthil and Man!

[02/25] Invited to serve as TPC member of EMSOFT, ESWeek'25.

[01/25] Give an invited seminar at UC Merced.

[01/25] NeurIT is accepted by ICRA 2025. Congrats to Xinzhe!

[12/24] Invited to serve as a TPC member of FMSys 2025 and Shadow TPC of CoNEXT 2025.

[11/24] We are organizing HumanSys 2025.

[10/24] Invited to serve as a TPC member of MobiSys 2025.

[07/24] Gave an invited talk at Peking University.

[07/24] RS-BNN is accepted by IEEE TVT.

[06/24] Invited to serve as a TPC member of ICPADS 2024 and a session chair of ICDCS 2024. See you in NYC!

[04/24] MuSAC is accepted by ICDCS 2024.

[04/24] Selected as a CPS Rising Star.

[04/24] Honored to join Schmidt Science Fellows 2024 cohort!

[02/24] Invited to serve as Co-Chair for the 2024 SenSys/BuildSys Joint Ph.D. Forum, and as an AEC member for MobiCom 2024.

[12/23] BG-BERT is accepted by ICASSP 2024. Code available.

[10/23] Selected for the N2Women Young Researcher Fellowship and organized the N2Women event at SenSys 2023.

[10/23] HandFi is accepted by SenSys 2023 and has been filed as a patent.

[09/23] Joined HKU. Hit me up when you are in Hong Kong!

[09/23] Honored to be listed in the Singapore 100 Women in Tech.

[08/23] Gave invited talks at Zhejiang University and Zhejiang Lab.

[07/23] Spent a wonderful month at ShanghaiTech University.

[06/23] Successfully defended my Ph.D. thesis.

[01/23] JPTS is accepted by ICC 2023.

[12/22] Gave an invited Student Lecture Series talk on SiFall. Video available.

[10/22] SiFall is accepted by SenSys 2022.

[01/22] Gave an invited Student Lecture Series talk on CLNet. Video available.

[10/21] 1st runner-up in the Masked Face Recognition Challenge, ICCV 2021.

[07/21] CLNet is accepted by IEEE Wireless Communications Letters.

[06/20] 2nd runner-up in the AI Meets Beauty Challenge, ACM MM 2020.

[05/20] 2nd runner-up in the EmotioNet Challenge, CVPR 2020.

Selected Publications

* denotes co-first/corresponding author. ^ denotes mentored students.

Nature Sensors

Noninvasive continuous lipid profiling via cofactor-refreshing cascading enzymatic reactions and causal machine learning

José A. Lasalde-Ramírez*, Chihyeong Won*, Sijie Ji*, …, Wei Gao*

MobiSys 2026

AquaCode: Turning Transaction Platforms into Non-Invasive Liquid Quality Checker

Sijie Ji*, Sheng Lyu*, Wenjian Li, Wei Gao

PDF · PPT · Demo

Under Revision

Science

Decoding Non-Invasive Molecular Signatures of Pain via Nanophotonic Mass Spectrometry

Moon-Ju Kim*, Sijie Ji* ,…, Wei Gao

PDF · Project

TMC 2026 ICDCS 2024

MuSAC: Toward Communication-Free Sensory Data Acquisition

Sijie Ji, Yiwei Wang^, Lixiang Lixiang

PDF

Tech Report ACL 2025 SenSys 2025

Mindguard: Towards Accessible and Sitgma-free Mental Health First Aid via Edge LLM

Sijie Ji, Xinzhe Zheng*^, Jiawei Sun^, Renqi Chen^, Wei Gao, Mani Srivastava

PDF · PDF · Project

SenSys 2023

Construct 3D Hand Skeleton with Commercial WiFi

Sijie Ji, Xuanye Zhang^, Yuanqing Zheng, Mo Li

PDF · Project · Code

SenSys 2022

SiFall: Practical Online Fall Detection with RF Sensing

Sijie Ji, Yaxiong Xie, Mo Li

PDF · Demo

Highly Cited

WCL 2021

CLNet: Complex Input Lightweight Neural Network for CSI Feedback

Sijie Ji, Mo Li

PDF · Code

More Publications

[ICC'23] JPTS: Enhancing Deep Learning Performance of Massive MIMO CSI Feedback — Sijie Ji, Mo Li.
[FMSys'24] HARGPT: Are LLMs Zero-Shot Human Activity Recognizers? — Sijie Ji, Xinzhe Zheng^, Chenshu Wu.
[ICASSP'24] Predicting Adverse Events for Patients with Type-1 Diabetes via Self-supervised Learning — Xinzhe Zheng^, Sijie Ji , Chenshu Wu.
[MM'25] CardioLive: Empowering Video Streaming with Online Cardiac Monitoring via Audio-Visual Learning — Sheng Lyu^, Ruiming Huang^, Sijie Ji, et al.
[IET Radar'23] Excellent Paper Award. Joint location design and resource allocation for ISAC — Yuanhao Cui, Weijie Yuan, Sijie Ji*, et al.
[IMWUT/UbiComp'25] USpeech: Ultrasound-Enhanced Speech with Minimal Human Effort via Cross-Modal Synthesis - Luca Jiang-Tao Yu, Running Zhao, Sijie Ji, et al.

View Full List on Google Scholar

Academic Services

Organizer

TPC Co-Chair of HumanSys (MobiCom 2026)
General Co-Chair of HumanSys (CPS-IoT Week), 2025
PhD Forum Co-Chair of BuildSys 2025
PhD Forum Co-Chair of SenSys/BuildSys 2024
N2Women@SenSys 2023

Session Chair / TPC

VTC Fall'23, ICDCS'24, MobiSys'25
TPC: ACL'25/26, SenSys'26, MobiSys'25, BuildSys'24/25, MobiCom'24 (AEC), EMSOFT'25/26, ACM MM'25/26

Invited Reviewer

IEEE TON, TMC, TWC, TCOM, WCL, CL, TVT, IOTJ, ACM IMWUT, TIOT, CVPR, ACL, GlobeCom, ICC, INFOCOM, Science Advances, Nature Machine Intelligence

Editorship

Electronics(SI) - Ubiquitous Computing and Applications in Digital Healthcare Systems

Frontiers in Public Health (SI) - Digital Integration of Biomarkers and Risk Prediction for Chronic Disease Prevention in Public Health

Awards & Honors

mHealth Scholar, 2026
MobiSys Rising Star, 2026
Schmidt Science Fellow, 2024
CPS Rising Star, 2024
N2Women Young Researcher Fellowship, SenSys 2023
Singapore 100 Women in Tech, 2023
1st runner-up in the Masked Face Recognition Challenge, ICCV 2021.
2nd runner-up in the AI Meets Beauty Challenge, ACM MM 2020
2nd runner-up in the EmotioNet Challenge, CVPR 2020.