Wi‑Fi heartbeat detection: UC Santa Cruz’s Pulse‑Fi can read your pulse without a wearable
Researchers at the University of California, Santa Cruz developed Pulse‑Fi, a contactless system that uses standard Wi‑Fi radio waves and machine learning to detect heartbeats from up to about 10 feet away, accurately and cheaply — no wearable required.
Key takeaways
- Contactless pulse detection: Pulse‑Fi measures tiny changes in standard Wi‑Fi radio waves caused by a beating heart using low‑cost hardware and ML.
- Short‑range and fast: Works from about 10 feet and can reach ~±0.5 beats-per-minute error after five seconds, improving with longer monitoring and better chips.
- Affordable hardware: The team used ESP32 modules and Raspberry Pi‑class options; models were trained on a custom dataset validated against pulse oximeters.
- Privacy questions: Passive, nonconsensual collection and data security need legal and technical safeguards before wide deployment.
How Pulse‑Fi works
Wi‑Fi devices emit radio frequency (RF) waves that bounce around a room. When those waves pass near a person, the body alters reflections and absorption. The minute chest movements from each heartbeat impose tiny, regular shifts on the RF signal. Pulse‑Fi captures those shifts with a low‑cost transmitter and receiver and isolates the heartbeat signal from background noise.
The raw Wi‑Fi traces are noisy; the researchers used machine learning to teach models to recognize heartbeat patterns within that noise. They built a custom dataset because no public dataset covered these subtle Wi‑Fi variations, then validated results by comparing to clinical pulse oximeters.
Read the UC Santa Cruz release for technical context: University of California, Santa Cruz news release and an external overview at Earth.com.
Performance and accuracy
Early results are encouraging: the team reports an error margin near half a beat per minute after about five seconds of monitoring. Accuracy improves with longer observation windows and higher‑quality Wi‑Fi chips. Quick spot checks are already viable; continuous monitoring could become more robust over time.
Coverage is roughly up to 10 feet in the reported experiments, though range and fidelity depend on room layout, antenna quality, and interference. For hardware comparisons and reporting, see the Tom’s Hardware piece: Tom’s Hardware coverage.
Hardware and cost
A central strength of Pulse‑Fi is affordability. The researchers tested inexpensive ESP32 Wi‑Fi chips (roughly $5–$10 each) and noted improved results with more capable single‑board computers such as Raspberry Pi class devices. That keeps system costs far below many medical devices and many commercial wearables, expanding potential use in low‑resource settings.
Research details and validation
Because no public Wi‑Fi heartbeat dataset existed, the team collected paired Wi‑Fi signal traces and pulse oximeter readings to create and label a custom dataset. Machine learning models were trained and validated on that data. The work was presented at the 2025 IEEE International Conference on Distributed Computing in Smart Systems and the Internet of Things (DCOSS‑IoT), allowing peer scrutiny of methods and early findings.
Future directions and applications
Researchers are extending Pulse‑Fi to detect respiratory rate and sleep‑related breathing irregularities such as apnea. If breathing detection proves reliable, the system could enable non‑intrusive sleep monitoring and caregiver alerts for dangerous breathing events without disturbing a sleeping person.
The low price and reliance on standard Wi‑Fi chips make commercial and smart‑home integration realistic: router makers, medical startups, and public health programs could add contactless vital‑sign monitoring to their offerings.
Privacy, security and regulatory questions
“Contactless monitoring raises clear benefits and clear questions.” Who can access passive pulse data on a home network? Could it be used without consent? Current law does not directly address passive heartbeat data gathered via Wi‑Fi.
These gaps suggest a need for strong technical safeguards, transparent opt‑in controls, and policy planning now as the technology matures. Security is equally important: data pipelines and models must be protected from tampering to preserve medical‑grade trust.
Who stands to gain
Pulse‑Fi may help people who don’t wear devices — seniors, those with skin sensitivities, or anyone who dislikes wearables. Clinics and low‑resource providers could add basic monitoring without large equipment purchases, and public‑health programs could scale low‑cost monitoring where wearables are impractical.
Implications for The High Desert, California
Economic impact
The High Desert’s many small towns and growing suburbs can face uneven health access. Affordable contactless monitoring could lower home‑care and clinic costs. Local manufacturers and tech shops could assemble inexpensive modules and offer installation or service, potentially creating jobs in assembly, software setup, and home‑health services across Victorville, Apple Valley and Adelanto.
Political consequences
Local officials will choose whether to regulate or encourage the technology. Conservative leaders who emphasize property rights and privacy can advocate for strong opt‑in rules, clear disclosure, and limits on nonconsensual monitoring while supporting pilot programs in county clinics and veterans’ services to demonstrate benefits.
Social effects
The region’s aging residents and veterans may benefit from easier, less intrusive checks. Caregivers could monitor loved ones remotely without repeated visits, potentially reducing emergency trips and enabling earlier detection of issues. Local nonprofits and senior centers could run pilot programs to test practical utility.
Cultural relevance
High Desert communities value independence and pragmatic solutions; a low‑cost, contactless option aligns with that ethos. That said, residents also prize personal control and privacy — deployments should include clear consent and opt‑in mechanisms.
Practical applications for residents
- Home health: Families could add Pulse‑Fi‑style monitoring to a router or hub to check on older relatives without extra gadgets.
- Small clinics: Rural clinics can use low‑cost hardware for in‑clinic or remote monitoring at modest expense.
- Local business opportunities: Entrepreneurs could provide installation, privacy‑focused services, and emergency‑alert integration for local residents.
Sources and further reading
University coverage: University of California, Santa Cruz news release
Technical reporting: Tom’s Hardware coverage
Overview: Earth.com overview
Policy perspective: Environmental News Network report
For commercialization or licensing inquiries, contact UC Santa Cruz’s Office of Innovation Transfer via the university press release page.
