Category Archives: Lab Progress

FID Finding: Final Post

In the final two labs our group searched for the Free Induction Decay signal of our mineral oil phantom. In order to do this we altered various parameters and attempted to eliminate sources of noise from our system. The three … Continue reading Continue reading

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FID Finding: Final Post

In the final two labs our group searched for the Free Induction Decay signal of our mineral oil phantom. In order to do this we altered various parameters and attempted to eliminate sources of noise from our system. The three … Continue reading Continue reading

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Getting an FID

For our lab before the most recent one, we tried to troubleshoot our set up since we were not obtaining any signal on the oscilloscope once the coil had been connected to the T/R switch, radio, and the various amplifiers … Continue reading Continue reading

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Making Spin Echo Acquisitions

We opened our gradient echo sequence that we generated using GNU Radio Companion during the last lab, which gave us control of the pulse signal amplitude, duration, and repetition time (TR). We noticed that when the TR exceeds about 100 … Continue reading Continue reading

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Everybody gets an FID!

In this lab, we started by confirming that we still could generate a signal with our magnet and see it on the oscilloscope as we did last lab.  Then, we connected the receive port to the GNU radio and we … Continue reading Continue reading

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Gradient coil simulations

Part 1. Uniformity over a whole cube was more uniform over a small subvolume than over the entire 20mm^3 volume.  (See below for code and z-gradient simulations). Part 2. We varied distances between rectangular loop coils for the transverse gradient, … Continue reading Continue reading

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Gradient Coil Design Homework

Maxwell Coils (z-Gradient Field) The uniformity of Gz for a Maxwell pair of coils 30mm apart was calculated for 10mm and 20mm cubed field of views. Uniformity was calculated as: where Bz is the measured gradient field, G is the … Continue reading Continue reading

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Quantifying Magnetic Field Uniformity

1) Quantify uniformity of Bz from a Maxwell Coil for a 20x20x20 mm cube and for a 10x10x10 mm cube. To quantify uniformity of Gz from a Maxwell Coil, we ran the MATLAB function simMaxwellCoil. This function plots the magnetic field … Continue reading Continue reading

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Gradient Coil Homework

We were given a short problem set on gradient coils.  The first problem required us to use simMaxwell.m to generate the gradient field.  Next we used this array to calculate the uniformity of the field for various values of d. … Continue reading Continue reading

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MATLAB Simulations on Gradient Coil Field Homogeneity

1) Recently, we were introduced to the topic of gradient coils and their designs. To help us visualize the coil configurations and the generated fields, we ran a few MATLAB simulations, which are shown below.   For the axial field … Continue reading Continue reading

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