Radio frequency (RF) transmit system for digital RF current source

A digital radio frequency (RF) current source for a magnetic resonance imaging (MRI) system, the digital RF current source comprising:

• a noise source;
• a dithering component electrically coupled to the noise source, where the dithering component generates a dithered RF input signal by combining noise received from the noise source with an RF input signal;
• an analog-to-digital converter (ADC) configured to receive the dithered RF input signal, where the ADC has a range and a reference, and where the ADC generates a sampled signal by sampling the dithered RF input signal;
• a noise shaping filter electrically connected to the ADC, where the noise shaping filter generates a noise shaped signal based, at least in part, on the sampled signal;
• an ADC to digital input decoder electrically connected to the noise shaping filter, where the ADC to digital input decoder converts the noise shaped signal to a digital input signal;
• a plurality of class D amplifiers electrically connected in parallel to the ADC to digital input decoder, where a member of the plurality of class D amplifiers has a first terminal and a second terminal, where the member of the plurality of class D amplifiers is configured to operate as a switch, where the member of the plurality of class D amplifiers is configured to receive the digital input signal at the first terminal, and where a first member of the plurality of class D amplifiers is configured to be controlled independently of a second, different member of the plurality of class D amplifiers;
• a plurality of transmission lines, where a member of the plurality of transmission lines has a length, and where the member of the plurality of transmission lines is electrically connected to the member of the plurality of class D amplifiers at the second terminal;
• and
• an MRI RF coil configured to transmit or receive an RF signal;
• where the plurality of class D amplifiers is electrically coupled in parallel to the MRI RF coil with the plurality of transmission lines.

A radio frequency (RF) transmit system for a digital RF current source, the system comprising:

• a magnetic resonance imaging (MRI) system control console operably connected to a digital RF current source amplifier;
• where the digital RF current source amplifier is operably connected to an RF transmission coil;
• where the MRI system control console provides a digital control signal to the digital RF current source amplifier;
• where the MRI system control console provides a master RF current source clock signal to the digital RF current source amplifier;
• and
• where the digital RF current source amplifier provides an alternating current to the RF transmission coil.

A radio frequency (RF) transmit system for a digital RF current source, the system comprising:

• a magnetic resonance imaging (MRI) system control console operably connected to a console signal-to-bit pattern translator and a digital RF current source amplifier;
• a memory component operably connected to the console signal-to-bit pattern translator, where the memory component stores a set of digital bit patterns, where the memory component is further operably connected to the digital RF current source amplifier;
• where the MRI system control console provides a first control signal and a DC voltage to the console signal-to-bit pattern translator;
• where the console signal-to-bit pattern translator converts the first control signal to a second control signal and provides the second control signal to the memory component;
• where the memory component selects a bit pattern from the set of digital bit patterns based on the second control signal;
• where the memory component provides the bit pattern to the digital RF current source amplifier;
• and
• where the MRI system control console provides a master RF current source clock signal to the digital RF current source amplifier.