An analog-to-digital converter device may include an input multiplexer circuit having analog input terminals configured to receive a respective plurality of analog input signals. The partial private key is known to the user, but the processed biometric data is not. A flight management computer continuously monitors the location of the CDS bundle using GPS technology and determines a vector to a drop location based on stored GPS measurements. A user station desiring to hand off communication from one base station to another uses multiple available time slots at the target base station for exchanging control traffic messages with the target base station.