Systems, devices and methods for transmitting electrical signals through a Faraday cage
Embodiments of the present disclosure provide devices, methods, and systems that support electrical connection, signal delivery, and/or communication between internal and external portions of a Faraday cage. In some embodiments, devices and methods are provided for transmitting electrical signals through a waveguide port of a Faraday cage. In some embodiments, aspects of the present disclosure are employed to adapt a magnetic resonance imaging system for communications between a scanner room and a control room.
1. A method of controlling the transmission of audio signals detected by a microphone in the presence of gradient noise from a magnetic resonance imaging scanner, the method comprising:
monitoring audio signals detected by the microphone;
processing the audio signals within one or more frequency bands to determine whether or not voice detection criteria associated with a presence of voice is satisfied, wherein each frequency band is selected to avoid frequencies associated with gradient noise;
transmitting the audio signal when the voice detection criteria is satisfied.
2. The method according to claim 1 wherein the frequency bands are selected based on known frequencies of the gradient noise.
3. The method according to claim 2 wherein the frequency bands are selected to be at frequencies higher than the reciprocal of the repetition time, TR, of the magnetic resonance imaging sequence, and wherein the frequency bands are selected to avoid harmonics of frequencies associated with the gradient noise.
4. The method according to claim 3 wherein the frequency bands are selected to be centered on prime numbers.
5. The method according to claim 1 wherein the criteria comprises a threshold signal that should be exceeded by the audio signal.
6. The method according to claim 1 wherein the microphone is conduction microphone.
7. The method according to claim 1 wherein the audio signals are transmitted when the audio signals from a single frequency band satisfy the criteria.
8. The method according to claim 1 wherein the audio signals are transmitted when the audio signals from a plurality of frequency bands satisfy the criteria.
9. The method according to claim 8 wherein the criteria comprises separate thresholds for at least two frequency bands.
10. The method according to claim 1 wherein a plurality of frequency bands is employed, where the center frequencies of the frequency bands are distributed across the human audible frequency range.