The Chinese Defence Ministry, in its statement, said that in each incident, the Chinese vessel "kept normal observation and alert, and fire control radar was not used".

BBC: China rejects Japan radar-lock allegation

In addition, the official says, a floating X-band radar has to be modified to track the satellite's trajectory, and the "fire-control" systems on the Navy ships also needed modification.

CNN: Attempt to shoot down spy satellite to cost up to $60 million