The Rigvedic Aryans were not familiar with any kind of desert. However, an implied reference to Meru as the country of desert mounds near Kurukshetra has been traced in Taittiriya Aranyakas.
It was basically a rural culture, and cities had not emerged; no important place name is hence recorded. In the Rigveda it was because of the migratory nature of the tribes and in the later-Vedic period the regions come to be known by the names of the tribes who controlled them.