A communication system for safe wireless control of an manoeuvrable object (3), comprising a control unit (1) having means for operating the object and receiving means for wireless information, and a portable operating unit (2) having sending means for wireless information, where said information is divided in time slots (ts), each containing a data package (21). The receiving means comprises detecting means for detecting in a time part (tp) of a time slot the presence of said data package and calculating means for calculating upon a reception failure the number of time parts having no presence of said data package following a time slot with presence of said data package. The control unit exercises a control command when a data package with a correct information has been received within a number of time parts just exceeding a full time slot.