Abstract: A compact size wireless sensor for sensing a change of state that includes a sensor switch, a microprocessor, a wireless transmitter, a timer (e.g., a low power clock circuit), an antenna, and a coin cell battery power source. The coin cell battery, which is positioned in a stacking arrangement with the microprocessor, switch, and transmitter, allows the sensor to be of a significantly reduced size. Moreover, to provide long life despite a small battery, the microprocessor is run in a standby mode in which the microprocessor draws little power unless it actually samples the state of the sensor switch during select intervals. Various electronic components individually, or in combination, assist in the sampling (monitoring mode) in such a way as to reduce current consumption from the power source. The compact size makes the sensor ideally applicable for wireless intrusion systems embedded within hollow frames of windows and doors.

Abstract: An RF repeater for exchanging time division multiple access (TDMA) transmit and receive signals between a mobile handset and a CATV plant or other signal conduit has a signal timing detector responsive to the timing of transmit signals being broadcast to the handset to provide timing information indicative of the timing of receive signals being received from the handset. A signal level detector responsive to the signal level of the receive signals provides signal level information. A signal control device responsive to the timing information and the signal level information provides a signal level control output for time slotted control of the receive signals. The timing and signal level information may be used to effect diversity selection between receive signals from two spaced antennas at the repeater and/or diversity selection may be effected between two versions of the receive signal at a base station after passing through the signal conduit.