Processing of variant-precision problem in error test of ring laser gyro

Variance(or Allan variance) analysis method is widely used in the error test of ring laser gyro(RLG).Various error sources are distinguished through regression of σ~2(τ) at different sample time.The dada points by which σ~2(τ) is calculated goes small when the sample time is very long,this makes bad precision of(σ~2(τ)).If σ~2(τ) at long sample time are not used,the data for the regression points becomes less,and this brings lower precision of fitting result.Weighted regression model is proposed to processe variant-precision problem in error test of RLG.