Programmable data acquisition system with a microprocessor for correcting magnitude and phase of quantized signals while providing a substantially linear phase response

A programmable data acquisition system comprising:

• a plurality of input signal channels for receiving a respective input signal during a normal mode of operation;
• circuit means for selecting respective ones of said plurality of channels to receive predetermined reference signals during a test mode of operation while uninterruptedly providing the normal mode of operation in any remaining unselected channels in said data acquisition system;
• an analog-to-digital converter system for supplying a stream of quantized electrical signals at a predetermined rate, said converter system being responsive to any signals carried in said plurality of signal channels as selected by said circuit means;
• a control unit for supplying respective control signals to the circuit means and to the converter system;
• and
• a microprocessor interface coupling said control unit to an external microprocessor having a magnitude corrector and a phase corrector, said microprocessor interface providing a microprocessor-derived control word from said microprocessor to said control unit, said microprocessor interface further transferring the stream of quantized electrical signals supplied by the converter system to said microprocessor so that said phase corrector provides a predetermined phase angle correction over a predetermined passband to the quantized signals transferred to said microprocessor from said converter system while said magnitude corrector provides a predetermined magnitude correction over said predetermined passband, said magnitude and phase correctors each having a substantially linear phase response over said predetermined passband.