I don't know "THE" pattern but I see 3-4 block designs. I took a look-see in my "1000 Great Quilt Blocks" book, and found these:
Working from the center out, I see a variation of an Economy block. The outer blocks look like a combination of a single "H" section (of the Four H block) centered in a Chimneys and Cornerstones. The corners look like a section of the Economy.
???????????????? Just 'cuz it's in print, don't make it so.