Substitutions and Cantor real numeration systems

We consider Cantor real numeration system as a frame in which every
non-negative real number has a positional representation. The system is defined using a bi-infinite sequence B=(\beta_n)_{n\in Z} of real numbers greater than one. We introduce the set of B-integers and code the sequence of gaps between consecutive B-integers by a symbolic sequence in general over the alphabet N. We show that this sequence is S-adic. We focus on alternate base systems, where the sequence B of bases is periodic and characterize alternate bases B, in which B-integers can be coded using a symbolic sequence v_B over a finite alphabet. With these so-called Parry alternate bases we associate some substitutions and show that v_B is a fixed point of their composition. The paper generalizes results of Fabre and Burdík et al. obtained for the Rényi numerations systems, i.e., in the case when the Cantor base B is a constant sequence.