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Inflation produces nearly Harrison-Zel'dovich scalar and tensor perturbationspectra which lead to anisotropy in the cosmic microwave background (CMB). Theamplitudes and shapes of these spectra can be parametrized by $Q_S^2$, $r\equivQ_T^2/Q_S^2$, $n_S$ and $n_T$ where $Q_S^2$ and $Q_T^2$ are the scalar andtensor contributions to the square of the CMB quadrupole and $n_S$ and $n_T$are the power-lawspectral indices. Even if we restrict ourselves to informationfrom angles greater than one third of a degree, three of these observables canbe measured with some precision. The combination $130^{1-n_S}Q_S^2$ can beknown to better than $\pm 0.3\%$. The scalar index $n_S$ can be determined tobetter than $\pm 0.02$. The ratio $r$ can be known to about $\pm 0.1$ for $n_S\simeq 1$ and slightly better for smaller $n_S$. The precision with which $n_T$can be measured depends weakly on $n_S$ and strongly on $r$. For $n_S \simeq 1$$n_T$ can be determined with a precision of about $\pm 0.056(1.5+r)/r$. Afull-sky experiment with a $20'$beam using technology available today, similarto those being planned by several groups, can achieve the above precision. Goodangular resolution is more important than high signal-to-noise ratio; for agiven detector sensitivity and observing time a smaller beam providessignificantly more information than a larger beam. The uncertainties in $n_S$and $r$ are roughly proportional to the beam size. We briefly discuss theeffects of uncertainty in the Hubble constant, baryon density, cosmologicalconstant and ionization history.Comment: 28 pages of uuencoded postscript with 8 included figures. A  postscript version is also available by anonymous ftp at  ftp://astro.uchicago.edu/pub/astro/knox/fullsim.p

Determination of inflationary observables by cosmic microwave background anisotropy experiments