Patent ReferencesPrecision automatic local time decoding apparatus Time synchronization master station and remote station system Electronic watch with an automatic time indication modifier Watch pager system and communication protocol Pager based information system High capacity protocol with multistation capability Method and apparatus for precision time distribution in telecommunication networks Automatic time zone adjustment of portable receiver Paging and time keeping system with transmission of time slot identification used for synchronization Paper multi-level group messaging with group parsing by message InventorAssigneeApplicationNo. 740587 filed on 10/31/1996US Classes:340/7.38, Time based340/309.16, Timer control368/47, With wireless synchronization368/55, By communication means370/310COMMUNICATION OVER FREE SPACEExaminersPrimary: Horabik, MichaelAssistant: Beaulieu, Yonel Attorney, Agent or FirmInternational ClassH04M 011/00AbstractA system is described for providing one or more remote paging receivers with accurate time of day information utilizing a paging provider which encodes page messages into RF signals corresponding to baseband signals for transmission via a paging channel to the receivers. The system includes the receivers and a controller. The controller sends a first page message, which defines an on-time point, to the paging provider for transmission via the paging channel to the receivers, and then sends a second page message to the paging provider for transmission via the paging channel to the receivers. Further, the controller detects the transmission of the first page message in the paging channel and determines a time of day when the on-time point of the first page message was transmitted by the paging provider in the paging channel. The second page message sent by the controller comprises data defining this determined time of day. The receivers each detect the first and second page messages in the paging channel, and have a clock for maintaining the time of day. Each of the receivers updates its clock to an accurate time of day responsive to the time of day of the clock when the on-time point of the first page message was received and the time of day defined by the data of the detected second page message. Thus, the receivers are provided with accurate time of day information for maintaining the accuracy of their clocks. In addition, such receivers may output periodically the time of day from their clocks to provide a source for accurate time of day information to other systems.Field of SearchCOMMUNICATION OVER FREE SPACEUsing time division multiplexing Synchronization With wireless synchronization By communication means Using plural paths or channels Plural carrier frequencies Synchronization Variable time delay modulation HAVING LIGHT WAVE OR ULTRASONIC LINK FOR SPEECH OR PAGING SIGNAL | |