Magnetic resonance imaging apparatus
A magnetic resonance imaging apparatus according to an embodiment includes a main apparatus and a coil apparatus that is separate from the main apparatus. The main apparatus transmits a wireless signal acquired by frequency-modulating a binary signal based on a first clock signal generated from a first system clock. The coil apparatus generates a second clock signal by dividing the received wireless signal, and generates a second system clock from the generated second clock signal. Frequencies of the second system clock and the first system clock are the same.
1 . A magnetic resonance imaging apparatus, comprising:
a main apparatus; and
a coil apparatus that is separate from the main apparatus, wherein
the main apparatus generates a binary signal based on a first clock signal that is generated from a first clock of the main apparatus, frequency-modulates the generated binary signal so as to convert the binary signal into a wireless signal with a predetermined frequency, and transmits the wireless signal,
the coil apparatus generates a second clock signal by dividing the received wireless signal, and generates a second clock of the coil apparatus from the generated second clock signal, and
frequencies of the second clock and the first clock are identical.
2 . A magnetic resonance imaging apparatus, comprising:
a main apparatus; and
a coil apparatus that is separate from the main apparatus, wherein
the main apparatus comprises processing circuitry configured to:
generate a first clock signal from a first clock of the main apparatus;
generate a binary signal based on a first clock signal that is generated from a first clock of the main apparatus, frequency-modulates the generated binary signal so as to convert the binary signal into a first electrical signal with a predetermined frequency, and transmit the first electrical signal to the coil apparatus by first wireless communication; and
receive a second electrical signal transmitted from the coil apparatus, the coil apparatus comprises processing circuitry configured to:
generate a second clock signal by dividing the first electrical signal transmitted from the main apparatus, and generate a second clock of the coil apparatus from the generated second clock signal;
output, as the second electrical signal, a magnetic resonance signal emitted as an electromagnetic wave from a subject;
digitalize the second electrical signal based on the second clock; and
transmit the digitalized second electrical signal to the main apparatus by second wireless communication, and
frequencies of the first clock and the second system clock are identical.
3 . The magnetic resonance imaging apparatus according to claim 1 , wherein the binary signal has a DC balance of substantially 0 at least in a transmission period of the wireless signal.
4 . The magnetic resonance imaging apparatus according to claim 1 , wherein the binary signal is a random signal with a run length of 5 bits or less.
5 . The magnetic resonance imaging apparatus according to claim 1 , wherein the main apparatus initializes the binary signal after power is turned on.
6 . The magnetic resonance imaging apparatus according to claim 1 , wherein the main apparatus superimposes a control signal defining an operating state of the coil apparatus on the wireless signal.
7 . The magnetic resonance imaging apparatus according to claim 1 , wherein the main apparatus comprises processing circuitry configured to:
generate the first clock signal from the first clock;
frequency-modulate the binary signal so as to convert the binary signal into a first electrical signal with a predetermined frequency, and transmit the first electrical signal as the wireless signal to the coil apparatus by wireless communication; and
receive a second electrical signal from the coil apparatus, the second electrical signal being acquired by digitalizing a magnetic resonance signal emitted as an electromagnetic wave from a subject based on the second clock.
8 . The magnetic resonance imaging apparatus according to claim 1 , wherein the coil apparatus comprises processing circuitry configured to:
generate the second clock signal by dividing the wireless signal, and generate the second clock from the second clock signal;
output, as a second electrical signal, a magnetic resonance signal emitted as an electromagnetic wave from a subject;
digitalize the second electrical signal based on the second clock; and
transmit the digitalized second electrical signal to the main apparatus by wireless communication.
9 . The magnetic resonance imaging apparatus according to claim 2 , wherein frequencies of the first wireless communication and the second wireless communication are different.
10 . The magnetic resonance imaging apparatus according to claim 3 , wherein the main apparatus adds a bit for correcting the DC balance for each cycle of the binary signal.
11 . The magnetic resonance imaging apparatus according to claim 6 , wherein the coil apparatus demodulates the wireless signal, and extracts the control signal.