Frequency approach to nonlinear dispersive waves

Coupled equations are derived which describe the evolution of harmonic content for quadratic nonlinearity in the presence of arbitrary attenuation and dispersion. The equations are shown to be in agreement with known results of nonlinear acoustics and to describe novel phase locking and parametric phenomena when applied to dispersive systems. They are well suited to a planned computer analysis concerning the existence of solitary waves in systems with topological dispersion.