Abstract: An infrared (IR) communication system is described in which a base unit for a cell can communicate with a plurality of infrared portable devices through distributed infrared receiver/transmitter (RT) modules over a plurality of channels using IR carrier signals. A call or signal processor, referred to as a radio exchange unit, and controlling communication of a cell, communicates with the base unit to place or receive calls with the IR portable devices. The communication occurs in standard communication frames divided into transmission and receiving segments with each segment further divided into slots and with the slots containing digital data, with each communication channel formed by a slot. Each transmission segment to an RT module is immediately followed by a responsive receiving segment.

Abstract: An infrared (IR) communication system is described in which a base unit for a cell can communicate with a plurality of infrared portable devices through distributed infrared receiver/transmitter (RT) modules over a plurality of channels using IR carrier signals. A call or signal processor, referred to as a radio exchange unit, and controlling communication of a cell, communicates with the base unit to place or receive calls with the IR portable devices. The communication occurs in standard communication frames divided into transmission and receiving segments with each segment further divided into slots and with the slots containing digital data, with each communication-channel formed by a slot. Each transmission segment to an RT module is immediately followed by a responsive receiving segment.

Abstract: An infrared (IR) communication system is described in which a base unit for a cell can communicate with a plurality of infrared portable devices through distributed infrared receiver/transmitter (RT) modules over a plurality of channels using IR carrier signals. A call processor, referred to as a radio exchange unit, and controlling communication of a cell, communicates with the base unit to place or receive calls with the IR portable devices. The communication occurs in standard communication frames divided into transmission and receiving segments with each segment further divided into slots and with the slots containing digital data, with each communication channel formed by a slot. Each transmission segment to an RT module is immediately followed by a responsive receiving segment.

Abstract: The presence of particular faults in a machine is determined using constraint suspension and Qualitative Physics by propagating values indicative of received machine signals through a subset of model variables that are either unrestricted or partially restricted. The implicants of each value assigned to a variable of the subset of variables can be determined and other variables can be restricted according to the union of the implicants. Values for fully restricted and partially restricted variables can be propagated in order to further restrict any other variables. The values of variables can be either qualitative, quantitative, or both. A Qualitative Physics model of a machine can be constructed by providing a user with a graphical user interface allowing selection and interconnection of machine components for the model such that the user can define a landmark domain and apply the landmark domain to provide definitions of qualitative value spaces of variables of the model.

Abstract: The presence of particular faults in a machine is determined using constraint suspension and Qualitative Physics by estimating a time for performance for each of a plurality of machine test procedures and providing a summation, for each test procedure, of estimated times for performing portions of each of the test procedures. Portions of the machine test procedures which are unnecessary due to a present test configuration of the machine are not included in the summation. A particular test procedure is chosen from the group of machine test procedures by selecting the one of the machine test procedures having a highest test score where the test score varies inversely to the summation. The test procedure can be a component health assessment and/or an observation of a machine parameter.