The sensors used in the outdoor intelligent parking car detector are mainly ()?

For outdoor intelligent parking, geomagnetic sensors are the most commonly used technology in individual car detectors. These sensors are typically installed in the ground of each parking space. They work by detecting the change in the Earth's magnetic field caused by the large metallic mass of a vehicle parked above them. This method is highly reliable, energy-efficient (critical for battery-powered NB-IoT devices), and robust against various weather conditions like rain, snow, and temperature changes, making it ideal for outdoor environments.

A. Infrared sensors can be unreliable outdoors due to interference from sunlight and ambient temperature fluctuations, leading to false positives or negatives.
B. Ultrasound sensors are more suitable for indoor environments (e.g., mounted on the ceiling). Outdoors, their accuracy is affected by wind, rain, and temperature.
D. While camera-based systems exist, they are typically used to monitor multiple spaces and are more complex. For a single-space "detector," geomagnetic sensors are the predominant technology.

1. Huawei. Smart Parking Solution. Official solution documentation and case studies consistently describe the use of NB-IoT-based geomagnetic vehicle detectors as the core sensing component for individual outdoor parking spaces.

2. Huawei. HCIA-IoT V2.5 Training Material. The "Smart Parking" use case chapter details the architecture, which includes NB-IoT geomagnetic detectors installed in parking bays to report occupancy status.