PURPOSE: To obtain an induction system in which chaff patterns are removed in the directions of distance and angle when a target is subjected to fraud due to chaff, for example, and a larger target pattern is formed.

CONSTITUTION: The induction system comprises a circuit 10 reading out data for every distance from a first target memory 7, a RAM 12 located at the poststage thereof and recording data having continuous number of bits corresponding to the distance, and a second canceler 11 for removing a continuous target pattern based on the data stored in the RAM 12. The induction system further comprises 8 circuit 13 located at the poststage of the canceler 11 and writing the removed data in a memory for each angle, and a second target memory 14 storing the data.