Tunable impedance matching methods and circuits for protection against side-channel attacks

A method of mitigating a side-channel attack, the method comprising:

• transmitting signals between a first subsystem and a second subsystem of an electronic assembly;
• measuring an impedance characteristic associated with the signals as the signals are transmitted between the first subsystem and the second subsystem;
• determining, based on the impedance characteristic, that an electromagnetic (EM) probe is within range of the electronic assembly;
• and
• directing EM emissions from the signals away from the EM probe.

One or more non-transitory computer-readable media comprising instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising:

• receiving an impedance characteristic associated with signals that are transmitted between a first subsystem and a second subsystem on an electronic assembly;
• determining, based on the impedance characteristic, that an electromagnetic (EM) probe is within range of the electronic assembly;
• and
• determining component values for a tuning circuit with an adjustable impedance through which the signals are transmitted, wherein the component values are configured to cause EM emissions from the signals to be directed away from the EM probe.