（一）取得I1，取得I2。 （二）正值化I1 和I2。 （三）正值化后的I1 和I2 送往查表。 （四）取得查表结果Q1_Sig 和Q2_Sig 然后相减-(a) to obtain I1, I2. (two) in I1 and I2. (three) in after I1 and I2 to the table. (four) obtain look-up table results of Q1_Sig and Q2_Sig and then subtracting