  A new method is presented for the analysis of limit cycle oscillations in
mixed-feedback systems. The calculation of the limit cycle is reformulated as
the zero finding of a mixedmonotone operator, that is, of an operator that can
be expressed as the difference of two maximally monotone operators. The problem
can then be solved efficiently by borrowing existing algorithms that minimize
the difference of two convex functions. The potential of the method is
illustrated on the classical Van der Pol oscillator.
