Wireless Clock System and Method

Abstract

A wireless clock system includes a master clock or other master time source, and a plurality of slave clocks or repeater devices. Each slave clock can both wirelessly receive and wirelessly transmit time signals including current time data. To avoid conflicts among the slave clocks, each slave clock transmits time signals in a frequency-hopping manner over pseudo-randomized frequencies and at pseudo-randomized transmission start times. In another embodiment, power consumption at the slave clocks is minimized by activating and deactivating receivers within the slave clocks at predetermined times and at predetermined intervals, each interval being longer than the previous interval, until valid time signals are received from either the master clock or another slave clock. Calibration of the slave clock's time base is also performed.

1 - 25 . (canceled) 
     
     
         26 . A wireless clock system comprising:
 a master time source including means for wirelessly transmitting time signals containing time data; and   a plurality of slave clocks with hands to indicate the time of day;   each of the slave clocks including means for wirelessly receiving time signals which cause the slave clock to operate in synchronization with a source of the received time signals, the source of the received time signals for at least one of the slave clocks being the master time source and the source for each other one of the slave clocks being the master time source or another one of the slave clocks, each of said slave clocks being operable to receive time signals from both the master time source or another slave clock as the source of the time signal, and   each of the slave clocks further including means for wirelessly transmitting time signals containing time data to other slave clocks whereby the transmissions by the slave clocks are controllable to minimize or prevent signal conflict.   
     
     
         27 . The system of  claim 26 , wherein the master time source comprises a master clock. 
     
     
         28 . The system of  claim 26 , wherein the master time source comprises a cellular telephone transmission facility. 
     
     
         29 . The system of  claim 26 , wherein the master time source comprises a global positioning satellite facility. 
     
     
         30 . The system of  claim 26 , wherein the master time source comprises a wireless transmission facility configured to receive time data over the internet. 
     
     
         31 . The system of  claim 26 , wherein any slave clock may be configured to operate as the master time source. 
     
     
         32 . The system of  claim 26 , wherein the second time signals are transmitted by the wireless transmission means in the slave clocks in a frequency-hopping manner. 
     
     
         33 . The system of  claim 32 , wherein the frequency-hopping is performed in a pseudo-random manner. 
     
     
         34 . The system of  claim 26 , wherein the frequency-hopping is performed in a doubly pseudo-random manner, the second time signals being transmitted pseudo-randomly from among pre-selected radio transmission frequencies within a pre-selected range and at pseudo-randomly selected transmission start times within a pre-selected range, so as to minimize signal conflicts at the slave clocks. 
     
     
         35 . The system of  claim 26 , wherein the means for wirelessly receiving the time signals comprises a receiver portion of a transceiver, and the means for wirelessly transmitting the time signals comprises a transmitter portion of the transceiver, the transceiver being controlled by a micro-controller operating under software control. 
     
     
         36 . A method of operating a wireless clock system, comprising:
 wirelessly transmitting time signals from a master time source, the time signals containing time data;   wirelessly receiving time signals at each of a plurality of slave clocks which cause the slave clocks to operate in synchronization with a source of the received time signals, the source of the received time signals for at least one of the slave clocks being the master time source and the source for each other one of the slave clocks being the master time source or another one of the slave clocks, each of said slave clocks being capable and operable to receive time signals from both the master time source or another slave clock as the source of time signals; and   wirelessly transmitting time signals containing time data from each of the slave clocks whereby the transmissions by the slave clocks are controllable to minimize or prevent signal conflict.   
     
     
         37 . The method of  claim 36 , wherein the step of transmitting the time signals from the slave clocks is performed in a frequency-hopping manner. 
     
     
         38 . The method of  claim 36 , wherein the step of transmitting the time signals from the slave clocks is performed in a pseudo-random manner. 
     
     
         39 . The method of  claim 36 , wherein the frequency-hopping is performed in a doubly pseudo-random manner, the time signals being transmitted pseudo-randomly from among pre-selected radio transmission frequencies within a pre-selected range and at pseudo-randomly selected transmission start times within a pre-selected range, so as to minimize signal conflicts at the slave clocks.