What does wide-sense stationary mean?
A random process is called weak-sense stationary or wide-sense stationary (WSS) if its mean function and its correlation function do not change by shifts in time.
What is the difference between WSS and SSS?
According to the definition (by Heinrich Meyr, Marc Moeneclaey, Stefan A. Fechtel in "Synchronization, Channel Estimation, and Signal Processing") : strict-sense SP = not time dependent. wide-sense SP = not dependent on variable t (time)