HIGH-PERFORMANCE CLASS AB AMPLIFIER FOR MRI

THE PROPOSED WORK IS INTENDED TO REDUCE THE COST OF MAGNETIC RESONANCE DIAGNOSTIC IMAGING (MRI) BY DEVELOPING SUITABLE, LOW-NOISE, LOW-COST CLASS AB PULSE AMPLIFIERS WITH SUBSTANTIALLY LOWER INITIAL COSTS AND OPERATING COSTS. NOVEL TRANSFORMER GEOMETRIES AND MATERIALS ARE PROPOSED FOR REDUCING LEAKAGE AND LEAD INDUCTANCES BELOW 10-9H WHILE MAINTAINING ADEQUATE MUTUAL INDUCTANCE FOR BROADBAND USE FROM 5MHZ TO 140MHZ AT PULSE POWERS UP TO 5KW. SUBNANOSECOND HIGH-CURRENT SCHOTTKY DIODE CIRCUITS WILL PROTECT THE AMPLIFIER AGAINST OVERDRIVE AND MISMATCHED LOADS. THE PHASE I RESEARCH IS TO ESTABLISH THE UPPER PRACTICAL LIMITS ON THE PERFORMANCE SPECIFICATIONS FOR A SMALL, LOW-COST 200W CLASS AB BROADBAND PULSE AMPLIFIER MODULE. PHASE II WILL INVOLVE TOTAL SYSTEM INTEGRATION AND PROTOTYPE MANUFACTURING OF 5KW CLASS AB PULSE AMPLIFIERS FOR MRI. THESE UNITS ARE EXPECTED TO COST ABOUT $50K LESS THAN COMPARABLE CLASS A AMPLIFIERS AND SAVE $25K EACH PER YEAR IN ENERGY COSTS.