  A robust measurement of the clustering amplitude of the sub-mm population of
starburst galaxies requires large-area surveys (>> 1 deg^2). The largest-format
arrays subtend only 10 arcmin^2 on the sky and hence scan-mapping is a
necessary observing mode. Providing realistic representations of the
extragalactic sky and atmosphere, as the input to a detailed simulator of the
telescope and instrument performance, allows important decisions to be made
about the design of large-area fully-sampled surveys and observing strategies.
In this paper we present preliminary simulations that include detector noise,
time-constants and array geometry, telescope pointing errors, scan speeds and
scanning angles, sky noise and sky rotation.
