Cordless telephone system

A cordless telephone system constituted by a base communication unit which is connected to telephone line connections, and portable communication units which are individually connected to the base unit by cordless communication links, the telephone system effectively enhancing power saving efficiency. The battery saving period of idle portable units are changed at adequate timings based on the number of telephone lines used, so that the portable units sequentially perform intermittent receipt at equal intervals of T. While effecting substantially the same connecting operations as those of a prior art cordless telphone system which effects a BS operation at a period of T, the system of the present invention reduces the BS period required to a product of the period T and the number of telephone lines used, thereby reducing power which is consumed by each portable unit.