RF TRANSMISSION CIRCUIT, COMPLEX DIGITAL SYNTHESIZER AND MRI EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To enhance the stability of signal quality and to reduce cost. SOLUTION: Reference carrier frequency signal data I1 and Q1 are directly formed in a digital region by a complex digital synthesizer 30 and mixed with RF envelope signal data En in the digital region by RF envelope mixers 41 and 42 not only to be upconverted in the digital region by a digital frequency upconverter 60 but also to be subjected to analogue conversion to form an analogue RF pulse signal A1. The frequency upconverter or band pass filter of an analogue circuit becomes unnecessary and the stability of signal quality can be enhanced and cost can be reduced.