Abstract: In the present invention, a plurality of DGPS receivers are employed to determine receiver-satellite-specific differential correction values. In turn, satellite-specific differential correction values are determined as an average of the individual receiver-satellite-specific differential correction values for each of the tracked satellites. A discriminator is employed for determining a receiver-satellite-specific discriminant which may be sampled and subsequent determination of a receiver-satellite-specific statistical value thereof. The receiver-satellite-specific statistical values may then be employed for determination of a Detection Threshold value and other integrity information associated with each of the satellite-specific differential correction values. The ground station further includes a means for communicating the satellite-specific differential correction values and integrity information associated therewith to a DGPS airborne receiver.

Abstract: An integrating analog-to-digital converter system in which alternating and different combinations of signals are integrated, and which are selected for such integration both periodically and through an integrating result reaching a reference value in the periods. A digit count is provided as a system output indicating the time duration of integration of a selected signal combination in each period.