History effect of magnetization of ferrites in latching phase shifters

The phase accuracy of ferrite phase shifters is of great importance in determining the performance of passive phased array radar. It is usually considered to bear little direct dependence on properties of the ferrite cores. However, the history effect of magnetization (HEM ) of the ferrite core is proved to affect the accuracy considerably. This paper provides the manifestation of HEM, the way to control and the empirical parameter to predict this effect.