MRI RF Coil Analog-to-Digital Conversion Circuit
Solution Overview
Problem
Conventional magnetic resonance imaging apparatuses face increased costs and complexity due to the growing number of RF coil channels, which necessitate more analog circuitry components for signal multiplexing and separation.
Innovation Solution
The apparatus modulates magnetic resonance signals to different frequencies for each channel, outputs an analog multiplexed signal, and uses analog-to-digital conversion followed by digital separation, reducing the number of analog circuitry components and simplifying the circuit configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of RF coil channels is increased to acquire high-quality images or achieve high-speed imaging, then image quality and imaging speed are improved, but the number of analog circuitry components increases leading to increased cost and device complexity
Solution Approach 1:
The patent replaces analog signal separation circuitry with digital signal processing. Specifically, analog-to-digital conversion is performed once for the multiplexed signal, and then digital filtering is used to separate signals from multiple RF coil channels. This substitution of analog mechanical/electrical separation with digital processing reduces the number of analog circuitry components while maintaining the ability to handle increased numbers of channels for high-quality imaging
Solution Approach 2:
The patent changes the domain of signal processing from analog to digital. By converting the multiplexed analog signal to digital form and performing separation in the digital domain, the system can handle a larger number of channels without proportionally increasing analog circuitry. The digital filters can be programmatically adjusted to separate signals from any number of channels, making the system scalable for high-speed imaging applications
2Productivity
If the number of RF coil channels is increased to achieve high-speed imaging, then imaging speed is improved, but the number of analog circuitry components increases leading to increased cost
Solution Approach 1:
The patent replaces analog signal separation circuitry with digital signal processing. Specifically, analog-to-digital conversion is performed once for the multiplexed signal, and then digital filtering is used to separate signals from multiple RF coil channels. This substitution of analog mechanical/electrical separation with digital processing reduces the number of analog circuitry components while maintaining the ability to handle increased numbers of channels for high-speed imaging
Solution Approach 2:
The patent implements a universal digital filtering approach that can handle any number of RF coil channels through a single analog-to-digital converter. The digital filters are programmed to separate signals from multiple channels, making the system multi-functional and scalable. This universal approach allows the same hardware configuration to support high-speed imaging with varying numbers of channels without requiring additional analog circuitry for each channel
3Reliability
If analog filtering is used to separate multiplexed signals for each reception channel, then signal separation is achieved, but the number of analog circuitry components increases
Solution Approach 1:
The patent replaces analog signal separation circuitry with digital signal processing. Specifically, analog-to-digital conversion is performed once for the multiplexed signal, and then digital filtering is used to separate signals from multiple RF coil channels. This substitution of analog mechanical/electrical separation with digital processing reduces the number of analog circuitry components while maintaining the ability to handle increased numbers of channels for high-quality imaging
Solution Approach 2:
The patent merges the signal separation function into a single digital processing stage after one analog-to-digital conversion. Instead of having separate analog filters for each channel, the system combines all channel signals into one multiplexed analog signal, converts it once to digital, and then uses digital filtering to separate the channels. This merging approach maintains signal separation reliability while dramatically reducing the number of analog circuitry components
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces the number of analog circuitry components, lowers costs, and simplifies the circuitry configuration while maintaining effective signal separation across channels.
Implementation Method 1
The RF coil apparatus modulates the magnetic resonance signals to have different frequencies for each of the channels
Implementation Method 2
The analog-to-digital conversion circuitry converts the analog multiplexed signal to a digital multiplexed signal
Data Source
AI summary
According to one embodiment, a MRI apparatus includes an RF coil apparatus receiving MR signals by coil elements corresponding to channels, modulating the MR signals to have different frequencies for each of the channels, and outputting an analog multiplexed signal in which the MR signals with different frequencies are composited over the channels, and a receiver including ADC circuitry converting the analog multiplexed signal to a digital multiplexed signal, and predetermined number of separation channels separating the digital multiplexed signal, based on the number of the channels relating to composition of the MR signals with the different frequencies. The receiver stops a separation process of the digital multiplexed signal for separation channels not used in the separation process among the predetermined number of separation channels.