The invention as defined in claim 39 wherein said generated sequences are of the form Si={f0 s i , f1 s i , . . . fk s i , . . . } and said Latin square based sequences are generated in accordance with f k s i = ( a 2 ??? ??? k p ??? + ak + s i ) ??? mod ??? ??? p + Bp , where p, a and si are integers, p is a prime number or a power of a prime number, B is the frequency band, k is a dwell time int