  The inspiral and merger of supermassive black hole binary systems with high
orbital eccentricity are among the promising sources of the advanced
gravitational wave observatories. In this paper we derive analytic ready-to-use
first post-Newtonian eccentric waveform in Fourier domain with the use of
Hansen coefficients. Introducing generic perturbations of celestial mechanics
we have generalized the Hansen expansion to the first post-Newtonian order
which are then used to express the waveforms. Taking into account the high
eccentricity of the orbit leads to the appearance of secular terms in the
waveform which are eliminated with the introduction of a phase shift. The
waveforms have a systematic structure and as our main result these are
expressed in a tabular form.
