Monitoring system for preventing loss of contact between e.g. adult and child, comprises two portable units which generate alarm when given distance between them is exceeded

摘要

The system comprises two portable alarm units, each one being capable of generating at least one alarm signal when a pre-determined distance between the two units is exceeded. The units can be worn on the person or by an animal, preferably in jewellery or watches, and communicate with each other via radar, infra-red, ultrasound or radio-wave signals.