This is the same as the 3 strand celtic braid posted elsewhere, only reduced so it can be woven on 15 shafts and 7 treadles. Turned, it could be woven on an 8-shaft loom with 15 treadles, or using a skeleton tie-up or a table loom.
Here's a photo of what it looks like woven up, in two different fabrics:
I was able to reproduce the draft and played with it a bit and are now weaving some dishtowel with the pattern. Turning out just fine - thank you so very much for sharing your talent with me.