The localization performance of a new amplitude cancellation localization scheme (interchange amplitude cancellation localization scheme) under non ideal case according with actual condition is analyzed using analytical model, especialy the performance when the resolution and sensitivity of the detection system is limited, and the interchange between two sources is not complete. The effects of the parameters of the heterogenous object on the localization performance of the system using the new scheme are also discussed. The results show that the method can reduce the effects of the relative amplitude and phase between two sources on the system, obviously improve the localization precision, and detect the heterogeneity with smaller size, deeper and smaller absorption coefficient.