Design of a Barometric Altimeter Based on a Micro Pressure Sensor

摘要

This Paper presents the development of the barometric altimeter based on a micro absolute pressure sensor and the altitude-pressure equation. The circuit for the altimeter contains a constant current source, a special conditioning circuit, a low-pass filter, and an A/D converting chip. Its performance characteristics are tested. The whole device weighs only less than 7g, the operating voltage is 5V, and the operating current is less than 10mA. The altimeter can operate at the altitude of -50~600m, with a resolution of about 0.5m. The temperature drift and the pressure variation cause errors of the altitude measurement. Therefore, a GPS-aid method is designed to overcome these problems. The flight test has been also completed.