The video was showing a different SOC. Not the 9S18M1.
It had a fold out panel on the left of the antenna to increase it's area, and a vertical canvas covered attenna on the right in front of the main antenna.
You mean this one?
It's an original 9S18. Actually, pretty sophisticated for its day, 3D, pulse-to-pulse freq. hopping. Used with original Buk of year 1980. The Buk-M1 of year 1983 uses 9S18M1 with slotted array: