I think that you need to stop calling him because that will only make it worse. He is ignoring you for a reason and he obviously has reception if he wanted to contact you. If I were you I would stop all calls and wait until he gets home to confront him about the camping trip.
If your trying to salvage a broken relationship just tell him how much you care, how much you love him, all the fun times you've had together and see if any of it touches his heart. If not, I'm afraid you should call it quits and find someone else.