Kamionkowski et al. quantify the feasibility of future satellite missions finding inflationary gravitational waves in the cosmic microwave background

Luca Pagano, Asantha Cooray, Alessandro Melchiorri, and Marc
Kamionkowski (2008) Red density perturbations and inflationary
gravitational waves. Journal of Cosmology and Astroparticle Physics 04(009) April 2008. CaltechAUTHORS.