Secure modulation and demodulation

摘要

A system and method are disclosed for securely transmitting and receiving a signal. A nonlinear keying modulator is used in the transmitter to encrypt the signal using a nonlinear keying modulation technique. A nonlinear keying demodulator is used in the receiver to decrypt the signal.

主权项

1. A modulator circuit, comprising:
a feedforward filter; a processor; and a feedback filter characterized by a plurality of coefficients; wherein the processor is configured to apply one or more of a maximum function or a minimum function to a processor input signal to provide a processor output signal to be applied to an input of the feedback filter, the processor input signal being a combination of an output of the feedforward filter and an output of the feedback filter, wherein one or more of a configuration of the plurality of coefficients or a configuration of the one or more of the maximum function or the minimum function is based upon a key, and wherein the modulator circuit is comprised in a transmitter, and wherein the transmitter is configured to share the key with a receiving device to configure the receiving device.