复式查表正弦函数值生成方法

A New Algorithm for Sine Function Calculating Based on Look-up Double-Table

硬件实现正弦函数值计算在航空武器系统中经常用到。现有线性插值查表法占用大量存储资源并且计算精度不高,针对该问题,对线性插值查表法的计算误差规律进行分析,并在此基础上提出了复式查表法。复式查表法另建了一个表格,该表格经过一系列变换可以表示出普通线性插值查表法的计算误差。通过对线性插值查表误差的修正可以大幅度提高其计算正弦函数值的精度。仿真证明该方法能在不增加存储资源的情况下大幅度提高计算精度。

Hardware implementation of sine function arithmetic is often used in aerial weapon system. The existing linear interpolation look-up table method occupies a lot of storage resources with low calculation accuracy. Aiming at this issue, we analyzed the error law of the linear interpolation look-up table calculation and put forward a look-up double-table method based on the analysis. The look-up double-table method can establish another table, which may show common calculation error of linear interpolation look-up table method. Through a series of transformation, the correction of linear look-up table error can greatly improve the calculation accuracy of sine function value. The simulation shows that this method is feasible and the precision is high.