In the study of gravitational waves (GWs), the stochastic background generated by compact binary systems are among the most important kinds of signals. The reason for such an importance has to do with their probable detection by the interferometric detectors [such as the Advanced LIGO (ALIGO) and Einstein Telescope (ET)] in the near future. In this paper we are concerned with, in particular, the stochastic background of GWs generated by double neutron star (DNS) systems in circular orbits during their periodic and quasi-periodic phases. Our aim here is to describe a new method to calculate such spectra, which is based on an analogy with a problem of Statistical Mechanics. Besides, an important characteristic of our method is to consider the time evolution of the orbital parameters.