We report an interesting phenomenon of wavelength doubling bifurcation
s in the model of coupled (logistic) map lattices. The temporal and sp
atial periods of the observed patterns undergo successive period doubl
ing bifurcations with decreasing coupling strength. The universality c
onstants alpha and delta appear to be the same as in the case of perio
d doubling route to chaos in the uncoupled logistic map. The analysis
of the stability matrix shows that period doubling bifurcation occurs
when an eigenvalue whose eigenvector has a structure with doubled spat
ial period exceeds unity.