Phase-Coherent MRI Sensor Readout With Data-Recovered Clocks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Maintaining phase coherent signal acquisition becomes increasingly difficult with the increase in the number of coil elements in MR systems, necessitating a cost-effective and robust solution for clock and data recovery in magnetic resonance imaging systems.
Innovation Solution
A magnetic resonance imaging system with a digital serial communication network using a ring topology and clock and data recovery units that recover the clock directly from the incoming data stream without local or external references, compensating for variations in clock phase due to operational conditions by detecting propagation delays.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional CDR circuits with clock references are used, then phase coherent signal acquisition is achieved, but device complexity and cost increase
Solution Approach 1:
The invention extracts only the essential function of clock recovery from the traditional CDR circuit by removing the clock reference component. The clock is recovered directly from the incoming data stream using a simple frequency-locked loop that locks to a fixed frequency offset from the nominal data rate, eliminating the need for complex clock reference circuits while maintaining phase coherence.
Solution Approach 2:
The invention replaces expensive, complex clock reference hardware with a simplified frequency-locked loop implementation that uses basic frequency multiplication and phase detection. This approach uses cheaper, simpler components that can be easily integrated into each sensor node without requiring precise external clock references.
2Measurement precision
If the number of coil elements is increased, then signal detection capability is improved, but maintaining phase coherent signal acquisition becomes increasingly difficult
Solution Approach 1:
Each sensor node independently recovers its own clock from the incoming data stream using the frequency-locked loop mechanism. This self-service approach eliminates the need for centralized clock distribution and synchronization across multiple coil elements, allowing each node to autonomously maintain phase coherence regardless of the total number of elements in the array.
3Measurement precision
If local clock references are used in sensor nodes, then clock accuracy is improved, but cost and space requirements increase
Solution Approach 1:
The frequency-locked loop circuit performs multiple functions: it recovers the clock frequency from the data stream, provides frequency synthesis with fixed offset, and maintains phase coherence. This multi-functional approach eliminates the need for separate clock reference circuits, reducing space and energy requirements while maintaining clock accuracy through frequency locking to the data stream.
Data Source
AI summary
The invention relates to phase-coherent read-out of sensor nodes (3) of a magnetic resonance imaging system (1) with a digital serial communication network (2). According to the invention, the network (2) comprises multiple sensor nodes (3) for detecting a radio frequency signal from a patient who is under examination by the magnetic resonance imaging system (1), and a host node (4) which is connected to the sensor nodes (3) via a network link (5) for merging and processing digital sensor data received from the sensor nodes (3), wherein the host node (4) comprises a receiver (6) connected to the network link (5) for receiving data over the network link (5), and a transmitter (7) connected to the network link (5) for transmitting data over the network link (5), the sensor nodes (3) each comprise an analog-to-digital converter (8) for converting the detected radio frequency signal to the digital sensor data, a receiver (9) connected to the network link (5) for receiving data over the network link (5), a transmitter (10) connected to the network link (5) for transmitting data over the network link (5), and a clock and data recovery unit (11) with a clock device which is configured for miming on a preset free-running frequency, the frequency of the data transmission over the network link (5) is set to a fixed frequency relative to the preset free-running frequency of the clock devices, and the clock and data recovery units (11) are configured for generating a recovered clock signal for controlling the analog-to-digital converter (8) of their sensor node by regulating the frequency of the clock device of their sensor node (3) to lock to the frequency of the data transmission over the network link (5). In this way, the possibility of phase coherent sensory data acquisition with a magnetic resonance imaging system (1) is provided in a robust and cost-efficient way.