Nonlinear modulation

Nonlinear modulation is a method of changing a signal's properties, like its amplitude, frequency, or phase, where the relationship between the input message and the resulting signal is nonlinear—that is, not directly proportional or simple. Unlike linear modulation, where changes are directly proportional, nonlinear modulation involves complex interactions that can produce richer or more adaptable signals. This approach is often used in advanced communications to improve signal quality, security, or data transmission efficiency, especially in systems where the medium or hardware introduces nonlinear behaviors.