Abstract: A receiver is provided that has reduced power consumption and seldom operates erroneously. The receiver generally includes: an input circuit or photoreceptor that receives a modulated digital signal that can includes a preamble; a detector that detects the received digital signal and outputs a baseband signal; a comparator that compares baseband signal and a reference signal; an integration circuit that integrates baseband signal; hysteresis circuits that generates voltage signals based on an average value signal from integration circuit; a multiplexer that selects between the signals from the hysteresis circuits based on a digital output signal from comparator; and a pulse detection counter that counts the number of pulses of the digital signal from comparator and outputs a count signal to one of the hysteresis circuits.

Abstract: A particulate detector system is provided that can sense particulates (such as smoke in the air). The system employs a reflected light system that generally avoids making measurements of light intensity. Instead, coded signals are compared with one another to determine error rates between emitted light and detected light (across a chamber). Based on the error rate, processing circuitry can determine particulate concentration.

Abstract: A particulate detector system is provided that can sense particulates (such as smoke in the air). The system employs a reflected light system that generally avoids making measurements of light intensity. Instead, coded signals are compared with one another to determine error rates between emitted light and detected light (across a chamber). Based on the error rate, processing circuitry can determine particulate concentration.

Abstract: A receiver is provided that has reduced power consumption and seldom operates erroneously. The receiver generally includes: an input circuit or photoreceptor that receives a modulated digital signal that can includes a preamble; a detector that detects the received digital signal and outputs a baseband signal; a comparator that compares baseband signal and a reference signal; an integration circuit that integrates baseband signal; hysteresis circuits that generates voltage signals based on an average value signal from integration circuit; a multiplexer that selects between the signals from the hysteresis circuits based on a digital output signal from comparator; and a pulse detection counter that counts the number of pulses of the digital signal from comparator and outputs a count signal to one of the hysteresis circuits.