  In the past few years, the study of receptive field codes has been of large
interest to mathematicians. Here we give a complete characterization of
receptive field codes realizable by connected receptive fields and we give the
minimal embedding dimensions of these codes. In particular, we show that all
connected codes are realizable in dimension at most 3. To our knowledge, this
is the first family of receptive field codes for which the exact
characterization and minimal embedding dimension is known.
