土壤水分测量仪的数字滤波设计与实现

为提高土壤水分测量仪的测量精度,根据测量数据分布的特点,在软件设计上选用算术平均滤波和滑动平均滤波2种方法作为克服随机干扰的滤波方法,并对其滤波效果进行了研究.结果表明,随着滤波参数N的增大,测量数据的均方差和变异系数都有下降的趋势,测量结果的稳定性进一步提高.当滤波参数N相同时,算术平均滤波所得的平均相对误差相对要小,测量精确性相对要高.

Design and Realization of Digital Filter for Soil Moisture Meter

In order to enhance the measuring accuracy of the soil moisture meter,according to the experimental data distribution characteristic,we choose the arithmetic average filter and the slip average filter as the digital filter method to resistance the random disturbance in the software design.The result indicated that,along with filter parameter N enlargement,the standard deviation and the coefficient of variation of the experimental data had the drop tendency.And the measurement result stability further enhanced.Under the condition of same filter parameter N,the mean relative error of the arithmetic average filter obtained was lower relatively.