Abstract: A battery operated device includes a receiver for receiving a transmission that includes a postamble. A sensor, in a tire, measures a parameter of the tire and outputs data indicative of the parameter. A microprocessor is coupled to the receiver and the sensor. The microprocessor is configured to periodically partially awaken to determine whether the transmission is likely a forward link packet (FLP) by examining the postamble, and to transmit the data in a reverse link packet (RLP) in response to confirming that the transmission is a FLP.

Abstract: A battery operated device includes a receiver for receiving a transmission that includes a postamble. A sensor, in a tire, measures a parameter of the tire and outputs data indicative of the parameter. A microprocessor is coupled to the receiver and the sensor. The microprocessor is configured to periodically partially awaken to determine whether the transmission is likely a forward link packet (FLP) by examining the postamble, and to transmit the data in a reverse link packet (RLP) in response to confirming that the transmission is a FLP.

Abstract: A battery operated device includes a receiver for receiving a transmission that includes a postamble. A sensor, in a tire, measures a parameter of the tire and outputs data indicative of the parameter. A microprocessor is coupled to the receiver and the sensor. The microprocessor is configured to periodically partially awaken to determine whether the transmission is likely a forward link packet (FLP) by examining the postamble, and to transmit the data in a reverse link packet (RLP) in response to confirming that the transmission is a FLP.

Abstract: A system for conserving battery life in a battery operated device such as a tire tag where there are several modes of operation. The typical mode is the deep sleep mode where the tag is generally inactive (no clock is running; however, an RC watchdog timer is running, which uses very little power). The tag spends most of its time in this low power mode. The tag periodically partially awakens to a lucid sleep mode (when the watchdog timer times out), initiates a low-speed clock, determines if it is time to enter a search mode by examining a search mode counter and, if it is not time, adjusts the search mode counter (e.g., decrements the counter by one), and returns to the deep sleep mode. The tag sleeps in the deep sleep mode most of its life in an effort to conserve battery power. During the deep sleep mode, because the clock oscillators are OFF, a deep sleep counter is adjusted (incremented or decremented) periodically (e.g., about every 18 ms) by an internal R/C oscillator.

Abstract: A battery operated device includes a receiver for receiving a transmission that includes a postamble. A sensor, in a tire, measures a parameter of the tire and outputs data indicative of the parameter. A microprocessor is coupled to the receiver and the sensor. The microprocessor is configured to periodically partially awaken to determine whether the transmission is likely a forward link packet (FLP) by examining the postamble, and to transmit the data in a reverse link packet (RLP) in response to confirming that the transmission is a FLP.

Abstract: An electronic tire maintenance system is provided for measuring a parameter of a device at a first location. The system includes a sensor for measuring the device parameter and generating a data signal representing the measured parameter. The system also includes a microprocessor coupled to the sensor for activating the sensor on a first periodic basis to measure the device parameter. The microprocessor includes a memory for storing the generated data signal representing the measured parameter. A transmitter and a receiver are coupled to the microprocessor. The microprocessor periodically partially awakens to determine, on a second periodic basis, if a received transmission is a valid interrogation signal and, if so, fully awakens and responds to the valid interrogation signal, via the transmitter, by at least transmitting the last stored measured parameter.

Abstract: An electronic tire maintenance system is provided for measuring a parameter of a device at a first location. The system includes a sensor for measuring the device parameter and generating a data signal representing the measured parameter. The system also includes a microprocessor coupled to the sensor for activating the sensor on a first periodic basis to measure the device parameter. The microprocessor includes a memory for storing the generated data signal representing the measured parameter. A transmitter and a receiver are coupled to the microprocessor. The microprocessor periodically partially awakens to determine, on a second periodic basis, if a received transmission is a valid interrogation signal and, if so, filly awakens and responds to the valid interrogation signal, via the transmitter, by at least transmitting the last stored measured parameter.

Abstract: A sensing cavity is directed towards the radiation to be measured. An identical reference cavity is directed towards a heat sink which is maintained at a constant temperature. An electric heater and a temperature sensor are mounted on both the sensing cavity and the reference cavity. The temperature sensors are connected to a bridge which is powered only when an observation is made. The heater on the sensing cavity is controlled by bridge imbalance to equalize the temperature of the two cavities. The heater power is then a direct measure of the difference in the power entering the sensing cavity and the power entering the reference cavity. By knowing the power entering the reference cavity, the power entering the sensing cavity can be calculated. The two cavities are mounted together to a common heat sink and have a directly associated preamplifier circuit included in the modular mounting. A plurality of such sensors is used to obtain radiance measurements in many directions simultaneously.