Preamplifiers for MRI Coil Applications
MicroWave Technology has added two preamplifiers to their line of preamps for magnetic resonance imaging (MRI). Both are built using advanced, low noise GaAs devices and components with very low magnetism, a critical requirement for MRI coil applications.
The MSM series preamp achieves 0.45 dB noise figure with 28 dB gain at 1.5T (64 MHz), 3T (123 to 128 MHz) and 7T (298 MHz). It has a low input impedance of 2 Ω. Bias current is 15 mA at 10 V. The preamp is housed in a miniature surface-mount package with a footprint of 0.43 in. × 0.36 in. The MPE preamp was designed for 3T (123 to 128 MHz) applications and achieves noise figure as low as 0.4 dB with 27 dB gain, drawing 12 mA at 10 V. This preamp has a footprint of 0.74 in. × 0.5 in. Both the MSM and MPE preamplifiers have excellent linearity, 20 dBm IP3, and can withstand input power as high as 30 dBm.
The small size of the MSM series is ideal for MRI coils with a large number of channels. The MPE preamp is targeted at the low cost MRI coil market, yet it maintains excellent RF performance. Microwave Technology has been a major preamplifier supplier to MRI system and coil manufacturers for over 15 years and remains committed to supporting the medical equipment market.