Paul Joseph Cassidy1
1School of Engineering, Griffith University, Gold Coast, QLD, Australia
Analytical expressions are presented for MRI phased array preamplifiers in terms of blocking impedance, S21 decoupling, minimum noise factor and gain based on CMOS common-source inductively degenerated low noise amplifiers. These expressions support the idea of using a source impedance greater than 50 Ohms for enhanced decoupling and minimum noise factor at the expense of gain.