Capteur Présence: French Guide to Presence Detection Sensors

A capteur présence (French for "presence sensor") is a presence detection device that determines whether one or more human occupants are currently present within a defined space, including the case where the person is sitting motionless, lying down, or sleeping with no visible movement, using millimeter-wave (mmWave) radar technology at 60 GHz (57–64 GHz) with 7 GHz of bandwidth to detect the micro-Doppler signature of human breathing at 0.2–0.5 Hz from ranges of 6–8 meters. The capteur présence is fundamentally different from a passive infrared (PIR) motion sensor (détecteur de mouvement), which only fires when a warm body moves across its field of view and is unable to detect a stationary person. A modern 60 GHz mmWave capteur présence achieves a stationary-occupant true positive rate above 99% in controlled testing and above 95% in real-world deployment, with a false positive rate below 1% over a 24-hour period. The capteur présence is deployed in hotel rooms (chambres d'hôtel) for housekeeping coordination and energy management, in offices (bureaux) for occupancy-based HVAC and lighting control, in healthcare facilities (établissements de santé) for fall detection (détection de chute) and patient monitoring, and in residential smart homes (maisons intelligentes) for automated lighting and climate control.

This guide provides a comprehensive overview of the capteur présence, covering the technology, the performance characteristics, the use cases, and the selection criteria for choosing the right sensor for a specific application. The guide is written in English to serve the international French-speaking audience that searches for capteur présence but reads technical content in English. Whether you are in France, Belgium, Switzerland, Canada (Québec), Luxembourg, or any other French-speaking market, this guide will help you understand the options and make an informed decision.

Capteur Présence: The Technology

The technology behind a modern capteur présence is millimeter-wave (mmWave) radar.

Capteur Présence: mmWave Radar Basics

A mmWave radar capteur présence emits a frequency-modulated continuous wave (FMCW) chirp that sweeps across a defined bandwidth (typically 7 GHz at 60 GHz) over a short period (typically 50–200 microseconds). The reflected signal from objects in the detection zone is mixed with a copy of the transmitted chirp, producing a beat signal whose frequency is proportional to the range of the target. By performing a Fast Fourier Transform (FFT) on the beat signal, the sensor can determine the range of every object in the detection zone with a resolution of approximately 2.1 cm.

The sensor then analyzes the phase of the beat signal across successive chirps to determine the velocity of the targets. A stationary person produces a beat signal with a slowly varying phase (due to the micro-motion of breathing), while a stationary chair produces a beat signal with a constant phase. By analyzing the phase variation (the micro-Doppler signature), the capteur présence can distinguish a stationary human from a stationary object, enabling true presence detection.

Capteur Présence: Micro-Doppler and Breathing Detection

The micro-Doppler signature of human breathing is the key to detecting stationary occupants. The periodic motion of the chest wall during breathing (amplitude 5–20 mm, frequency 0.2–0.5 Hz) produces a Doppler modulation that is clearly detectable by a 60 GHz mmWave sensor with 7 GHz of bandwidth.

A well-designed capteur présence uses signal processing techniques to extract the breathing signature from the radar return, distinguish it from background noise (HVAC airflow, building vibration, fan motion), and use it as a positive indicator of human presence. The result is a sensor that can reliably confirm the presence of a sleeping adult at 4 m with a true positive rate above 99% in controlled testing.

Capteur Présence: Why PIR Sensors Cannot Detect Stationary Occupants

A passive infrared (PIR) sensor, known in French as détecteur de mouvement PIR, cannot detect stationary occupants. The PIR sensor detects changes in infrared radiation across its field of view, and a stationary person does not produce a change in the radiation pattern. The PIR sensor therefore reports "no motion" within 10–30 minutes after the last movement, even if the room is occupied.

This is the fundamental limitation that makes a PIR sensor unsuitable for use as a capteur présence in applications where the occupant may be stationary for extended periods.

Capteur Présence: Performance Metrics

The performance of a capteur présence is characterized by several key metrics.

Capteur Présence: Stationary-Occupant True Positive Rate

The stationary-occupant true positive rate (TPR) is the percentage of time that a stationary human occupant is correctly reported as present. For a 60 GHz capteur présence, the TPR is above 99% in controlled testing and above 95% in real-world deployment.

Capteur Présence: False Positive Rate

The false positive rate (FPR) is the percentage of time the sensor reports presence when the room is actually empty. For a well-designed capteur présence, the FPR is below 1% over a 24-hour period in a typical indoor environment.

Capteur Présence: Detection Range and Field of View

The detection range of a 60 GHz capteur présence is 6–8 m for stationary occupants and 8–12 m for moving occupants when ceiling-mounted at 2.5–3.0 m. The field of view is typically ±60° azimuth and ±40° elevation.

Capteur Présence: Detection Latency

The detection latency is the time between an occupant entering the detection zone and the sensor reporting the change. For a capteur présence, the latency is typically 0.5–3 seconds.

Capteur Présence: Applications

The capteur présence is deployed in a wide range of applications in French-speaking markets.

Capteur Présence: Hotel Rooms (Chambres d'Hôtel)

Hotel rooms are the canonical application for the capteur présence. A 60 GHz ceiling-mounted capteur présence can reliably detect whether a guest is in the room throughout their stay, including when they are sleeping, and feeds the occupancy data to the building management system for housekeeping coordination and the HVAC system for energy management.

In the French hotel market (Accor, Louvre Hotels, Barrière, Club Med), the capteur présence is increasingly being deployed in both new construction and renovation projects.

Capteur Présence: Offices (Bureaux)

Offices use the capteur présence for per-room HVAC and lighting control, conference room availability detection, and space utilization analytics. The sensor's ability to detect stationary occupants is essential for office applications where workers may be at their desks for hours without significant movement.

Capteur Présence: Healthcare (Établissements de Santé)

Healthcare facilities use the capteur présence for fall detection, bed-exit alerting, and occupancy-based environmental control. The privacy profile of mmWave radar (no images, non-invasive) makes it suitable for deployment in private spaces where camera-based sensing would be inappropriate.

Capteur Présence: Residential Smart Home (Maison Intelligente)

Residential smart homes use the capteur présence for occupancy-based lighting, HVAC control, and security monitoring. The most compelling use case for residential sensors is the prevention of the "light turned off while reading" problem that plagues PIR-based motion sensors.

Capteur Présence: French-Speaking Market Considerations

The French-speaking market for capteur présence has some specific considerations.

Capteur Présence: France Market

The French market is well-integrated into the European Union, with CE marking required for radio frequency devices. The hotel sector is a major adopter of capteur présence, and the office and residential sectors are also growing. The French market is served by both international vendors and local distributors and integrators.

Capteur Présence: Belgium and Luxembourg Markets

The Belgian and Luxembourg markets are also well-integrated into the European Union, with CE marking required. The hotel sector is a major adopter, and the office and residential sectors are growing. The markets are served by both international vendors and local distributors.

Capteur Présence: Switzerland Market

The Swiss market is not an EU member but follows the EU regulatory framework closely, with CE marking accepted. The hotel sector (especially in the Alpine resort regions) is a major adopter, and the office and residential sectors are growing.

Capteur Présence: Canada (Québec) Market

The Canadian market (especially Québec) is a major French-speaking market, with ISED (Innovation, Science and Economic Development Canada) certification required for radio frequency devices. The hotel sector is a major adopter, and the office and residential sectors are growing. The market is served by both international vendors and local distributors.

Capteur Présence: Selection Criteria

Selecting the right capteur présence for a specific application requires evaluating several criteria.

Capteur Présence: Technology

For indoor presence detection, 60 GHz mmWave radar is the default choice, providing reliable stationary-occupant detection with an excellent privacy profile.

Capteur Présence: Form Factor

For most applications, a ceiling-mounted sensor (70 mm diameter ceiling puck) is the right choice. For corridors and entryways, a wall-mounted sensor may be preferred.

Capteur Présence: Connectivity

The connectivity should match the existing infrastructure and the integration requirements. For hotel deployments, Zigbee is the most common. For office deployments, WiFi or PoE with BACnet is common. For residential deployments, Matter or Zigbee is the most common.

Capteur Présence: Certifications

The capteur présence should carry the required certifications for the target market. In the EU, CE marking is required. In Canada, ISED certification is required. In Switzerland, CE marking is accepted.

Capteur Présence: Privacy and Compliance

The privacy and compliance considerations for a capteur présence are similar to those in other markets.

In the EU, the GDPR and the French Loi Informatique et Libertés regulate the processing of personal data. A properly configured capteur présence that processes all radar data on-device and only transmits anonymous occupancy events is generally outside the scope of personal data.

In Canada (including Québec), the Personal Information Protection and Electronic Documents Act (PIPEDA) and the Québec Loi 25 regulate the processing of personal data, with similar principles.

Capteur Présence: Final Recommendation

The capteur présence is a mature, reliable technology that has become the default choice for presence detection in hotel rooms, offices, healthcare facilities, and residential smart homes across French-speaking markets. The 60 GHz mmWave radar is the default technology, providing reliable stationary-occupant detection, an excellent privacy profile, and a compact form factor.

For a procurement team or a consumer selecting a capteur présence, the right approach is to start with a clear definition of the application requirements, then evaluate the available products from international vendors (PresenceSensor, Aqara, Honeywell, Siemens) and local distributors and integrators, then select a product that meets the requirements and is supported by a local supplier with the necessary certifications for the target market. With the right sensor, correctly installed and integrated, the capteur présence can deliver a level of occupancy awareness that is impossible to achieve with PIR-based motion sensors, and can justify the higher unit cost through improved energy efficiency, better occupant experience, and more accurate occupancy data for downstream analytics.

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