Hammerfall by C.J. Cherryh
There is a slight hint of Dune, at least initially. First, this is really nothing more than the depiction of life on a desert planet. If one wanted to stretch a point one could also say the story involves the conflict between adversaries contesting the planet. But there is no real depth to the similarities.
The planet was colonized centuries ago, and as SF writers are so fond of doing, most of those living there are unaware of its history. They know there is a very powerful central leader, Ila, back in the capital city. Challengers have tried to lead an army to replace her, but have never succeeded.
Our story begins with a caravan in the desert with prisoners being led to the capital. The prisoners are the "mad" - those who hear voices, see visions of a tower and feel a beaconing to the east. Even the leader of the opposition forces has let his son, Marak, be sent off in the caravan, as the mad are repellent to most people and an embarrassment to their families.
Ila, however, suspects the mad are not simply insane. She perceives a similarity in the beaconing to a tower far across the desert. She has Marak lead an expedition of the mad to follow the force calling them.
A significant part of the book is then the experiences of their desert odyssey. Finally, after finding the tower, the story transforms into more than desert life, madness and everything else we've been told before. Now we get a broader perspective and learn of other technologies.
Like some of Cherryh's other books, parts of the story depend on this or that supposed future technology, but much of the experience of the character could take place in a novel about the pre-industrial past. Depending on the reader, this may or may not satisfy what they are looking for in SF.