A new Z search method is proposed which can significantly improve mean
acquisition time when compared with the best previous Z search strate
gy. The codephase search starts from a position offset from centre of
a range which has been determined from a priori information. The propo
sed search method includes previous Z search strategies as special cas
es. The distribution and mean of acquisition time have been developed
for the proposed search strategies. With minimum mean acquisition time
as objective, optimization of the starting position offset has been i
nvestigated.