I don't camp anymore but I do have sleep apnea and a SuperTenere
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I've slept on my stomach for as long as I can remember and I knew a CPAP wasn't going to work or did I want to try to make it work. I did the sleep study which was just horrible for me and was diagnosed with mlid to severe apnea. How they came up with that is beyond me, I don't think I fell asleep for more than 30mins.
My ENT suggested a dental appliance or oral device
https://aadsm.org/oral_appliance_therapy.php
My wife tells me it works, I've noticed a difference too. I've been using it for 5yrs or so. This could work for some and it's compact and would be perfect for camping.
Basically you have two dental trays, an upper and lower, they are joined by a bridge that shifts your lower jaw fwd and when in your mouth your jaws are locked in position to keep your airway open so the muscles, when they do relax, do not cut airflow. They are also adjustable.