Phase signal evaluation method to double fault tolerance

摘要

The invention relates to a method for unambiguously determining a physical parameter using m phase-measured values i with 1im, whereby the phase-measured values i have different, integer periodicity values ni and an integer periodicity difference (a) with n1 within an unambiguous range E of the physical parameter . A value T with (b) and (c) is calculated based on the phase-measured values i and the periodicity values ni thereof, and, within a reduced unambiguous range Ered with (d), a value V is allocated to the value T by allocation according to (e), wherein TUk stands for a respective lower limit and TOk for a respective upper limit of T. The allocation intervals between the upper (TOk) and the lower limits (TUk) for T, as wells as the distances (f) correspond at least to the periodicity difference n. In order to determine the physical parameter , value V is added up with the phase-measured values i in a weighted manner. ⁢ ⁢ n =  n i - n i - 1  ( a ) T = T ⁡ ( j , n i ) ( b ) j , l Z ⁢ { 1 , ⁢ , i } ( c ) E red = 1 ⁢ ⁢ n · E ( d ) V = V ⁡ ( T ) = { V 1 ⁢ f ⁢ u ¨ ⁢ r ⁢ ⁢ T T O ⁢ ⁢ 1 V 2 ⁢ f ⁢ u ¨ ⁢ r ⁢ ⁢ T U ⁢ ⁢ 2 T T O ⁢ ⁢ 2 V 3 ⁢ f ⁢ u ¨ ⁢ r ⁢ ⁢ T U ⁢ ⁢ 3 T T O ⁢ ⁢ 3 V k ⁢ f ⁢ u ¨ ⁢ r ⁢ ⁢ T T Uk ( e ) ⁢ ⁢ V =  V k + 1 - V k  ( f )