Isolation

Updated June 28, 2008

New for July 2008! This is a very basic topic, and it's about time we covered it.

Isolation refers to the ability to prevent a signal from appearing at a node in the circuit where it is unwanted. Isolations that you typically want to maximze between transmit and receive paths in a radar, between the off-port of a SPDT switch and the common-port, between the RF and LO ports of a mixer, or between paths in a dual-channel receiver.

Measuring isolation

There are at least three ways to measure the magnitude of an unwanted signal. A network analyzer can measure the transmission coefficient between