A radio transmission telemetry system includes many battery-operated radio transmitters
to intermittently transmit very short messages indicative or status of sensors
associated with the transmitters and a receiver to collect data from the sensors.
The transmitters transmit very short messages separated by long time intervals
independently of any receiver capable of receiving from any of the transmitters.
Each transmitter varies the frequency for each transmission and the time between
transmissions according to a sequence that is unique and based on the transmitter
ID code. The receiver holds information about the expected time and the expected
frequency of the future transmissions for each transmitter. The receiver identifies
each source of transmissions based on its unique variations of the transmission
time and frequency, thus eliminating the necessity to include any information about
the transmitter ID code in the transmitted messages.
