Research notes · Knowledge base

Sensing the body without touching it.

A growing collection of plain, readable knowledge pages on my research interests. Right now that means millimetre-wave radar for contactless vital sign detection: how a radar picks up breathing and heartbeat from a few metres away.

Browse the pages New to radar? Start here
LIVE CAPTURE · VITAL SIGNSFMCW RADAR
Screenshot of radar vital-sign software showing heart rate detected at 61 bpm, the range profile with the target at 0.61 m, the heart spectrum, the heartbeat waveform over the last 20 seconds and the heart-rate trend
A live capture from my radar processing software: the range profile finds the person, then the chest echo's phase gives the heartbeat waveform and heart rate.

Knowledge pages

Pages

Listed in reading order. New to radar? Start with 01.

Last updated 28 Oct 2026

01Start hereFundamentals

Tutorial · 12 parts · runnable Python

An intensive tutorial on FMCW radar fundamentals

A complete picture of a basic FMCW radar, built one layer at a time: the physical intuition first, then the mathematics derived step by step, then Python code that simulates each effect so you can see the equation working.

Covers The chirp signal, mixing and the IF signal, range and velocity measurement, range–Doppler maps, angle of arrival, windowing, CFAR detection, noise and SNR, a complete design example, and exercises.

Read
02Radar design

Tutorial · 27 Oct 2026

FMCW radar chirp parameters: a mathematical tutorial

Every number in a chirp configuration table follows from a handful of primitive settings and the antenna layout. This page derives each one for a 60 GHz radar with 3 transmitters and 4 receivers.

Covers The signal model, start frequency, slope and bandwidth, range and velocity resolution, angle resolution, frame timing, a full verification of every value, and a companion notebook.

Read

More pages on radar vital sign detection are on the way.

Research interests

What this site covers

Each interest gets its own set of pages. New topics are added as my research grows.

  • mmWave radar for vital sign detection Active · 2 pages
Illustrated portrait of Santana

About

Hi, I'm Santana.

I'm a freelance researcher with a technical background in radar signal processing and electromagnetics. My work sits where the physics of electromagnetic waves meets the algorithms that turn raw radar signals into useful measurements.

This site is my working archive. Each time I develop a new piece of work, I record what I learned along the way: the theory I had to revisit, the methods that worked, and the pitfalls that cost me time. Radar-based vital sign detection is the first topic, and other fields will follow.

If you're working in the same direction, I hope these notes save you some of that time.