In an information access system, a first reader/writer device cyclically transmits an information request signal at a first frequency in a first period and goes into an inactive state in a second period, and a second reader/writer device cyclically transmits an information request signal at the first frequency in the second period and goes into an inactive state in the first period. An active contactless information storage device senses a carrier of an RF signal at the first frequency in predetermined periods occurring in a predetermined cycle shorter than each of the first and second periods.