METHOD AND APPARATUS FOR TWO-WAY COMMUNICATIONS AMONGST A PLURALITY OF COMMUNICATIONS DEVICES

摘要

In a security system, a method and apparatus for two-way frequency hoppi ng communications between the control panel and each peripheral device which maintains channel synchronization through the assignment of fixed beacon frequencies for the transmission of synchronizing data. The use of frequency hopping provides high immunity to jamming and interference, reduced occurrence of multi-path phenomena, and allows for transmissions at a much higher output power than conventional fixed-frequency communications, to thus increase the effective range of the peripheral devices while providing effective and reliable two-way communications between the control panel and the peripheral devices. The invention also provides a large number of channels, which allows for actuators such as sirens, strobes and line seizing devices to be wireless in addition to sensors. The invention provides a high immunity to signal jamming, interference from other wireless systems and miss-detection due to multi-path phenomena; reduces opportunities for collision between peripheral transmissions; and eliminates the redundant emission of peripheral transmissions to reduce RF traffic in the vicinity of the system and extend the life of batteries used in the peripheral devices.