针对声纳高度计、全球定位系统(GPS)和气压高度计的高度定位应用,开发了一种基于现场可编程门阵列(FPGA)的数字高度计,具有成本低、速度快、功耗小的特点.FPGA完成声纳高度计、GPS和气压高度计的数据采集,高度信息处理,气压高度计温度补偿及串口输出等工作.对高度计的误差来源进行分析,重点对气压高度计的温度漂移现象进行了补偿修正.为了验证设计效果,对数字高度计进行了测试,测试结果表明:高度计在进行误差补偿后,在低空范围内误差为0.1m左右,高空范围内误差为2~3m,可用于普通导航领域.
Aiming at height location application of sonar altimeter, GPS and barometric altimeter, a kind of digital altimeter based on FPGA is developed, which has advantage of low cost, fast speed,low power consumption. FPGA is responsible for completion of sonar ahimeter, GPS and barometric altimeter data acquisition, height information processing, barometric altimeter temperature compensation, and serial port output. After analyzing barometric altimeter error sources, compensation and correction of temperature drift of barometric altimeter are emphasized on. In order to verify design effect,the digital altimeter is tested,and test results show that the precision of digital altimeter in a low range can reach 0.1 m or so,for high altitude range error is 2 -3 m after error compensation, which can be used for general navigation field.