  By employing the angular momentum projection technique we propose a method to
reliably calculate the quantum spectrum of nuclear collective rotation. The
method utilizes several cranked mean-field states with different rotational
frequencies and they are superposed in the sense of the configuration mixing or
the generator coordinate method, after performing the projection; the idea was
originally suggested by Peierls-Thouless in 1962. It is found that the spectrum
as a result of the configuration mixing does not essentially depend on chosen
sets of cranking frequencies if the number of mean-field states utilized in the
mixing is larger than a certain small value. We apply this method to three
examples employing the Gogny D1S effective interaction and show that it is
useful to study high-spin rotational bands by means of the angular momentum
projection method.
