A construction of pseudorandom binary sequences using both additive and multiplicative characters
In recent years, starting with the paper [B-D-S], we have investigated the possibility of characterizing countable subgroups of the torus by subsets of . Here we consider new types of subgroups: let be a Kronecker set (a compact set on which every continuous function can be uniformly approximated by characters of ), and the group generated by . We prove (Theorem 1) that can be characterized by a subset of (instead of a subset of ). If is finite, Theorem 1 implies our earlier result...
We prove upper bounds for sums of Kloosterman sums against general arithmetic weight functions. In particular, we obtain power cancellation in sums of Kloosterman sums over arithmetic progressions, which is of square-root strength in any fixed primitive congruence class up to bounds towards the Ramanujan conjecture.
Large families of pseudorandom binary sequences and lattices are constructed by using the multiplicative inverse and estimates of exponential sums in a finite field. Pseudorandom measures of binary sequences and lattices are studied.