Nonlinear junction detector

The non-linear junction detector, or an NLJD, is a device that illuminates a small region of space with high-frequency RF energy. Any "non linear junction" in the vicinity—for example, and particularly, the p–n junction—will receive this energy, and because of the asymmetric response of the junction to an electric field, it will mangle it, re-emitting some of it on multiples of the illumination frequency (see harmonic).

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