search

contsili / master-thesis

Comparisons between SQUID- and OPM-based MEG systems.
1 stars 0 forks source link

Aim 2.0 - OPM sensor selection #1

Closed contsili closed 10 months ago

contsili commented 10 months ago

This issue is related to commit e104426

When I ran the simulations, I vary the number of OPM sensors. That means that I need to select a subset of all the OPM sensors. As we discussed with @robertoostenveld this can be either done with Monte-Carlo simulations (which means that we need take out a different random sensor each time we ran the dipole fit iterations) or with mesh_sphere() function.

I decided to use the Monte-Carlo simulations. The same method is also used in Vrba, J. (2000). Multichannel SQUID biomagnetic systems. In H. Weinstock (Ed.), Applications of Superconductivity (Vol. 365, pp. 1–79). Boston; Kluwer Academic Publishers; 1999. http://www.mendeley.com/research/multichannel-squid-biomagnetic-systems/

To do that, I edited the code inside the ni2_sensors(). The user can now define the number of sensors in ni2_sensors() by using 'sensor_number' as an input argument.

Is my idea correct? And is my code reflecting my idea correctly?

robertoostenveld commented 10 months ago

Random taking a subset of the existing sensors is a fine approach with me. You should only keep in mind that this will result in non-uniform subsets of channels, which on average will be suboptimal for picking up the signal. No reason to change your strategy for now, just keep that in mind and document it in due time.

contsili commented 10 months ago

Notes from meeting - 24/10/2023

With @robertoostenveld we looked at the ni2_sensors() (e104426). My idea and the code is correct.