who made the Su37s reaward looking radar?

Does anybody know whether it was Phazotron or NIIP who made the tail radar of the Su37? Some sources (Including the airforce technology site) say it was NIIP, which makes sense becouse the designation of the radar is given as No12 (NIIP’s Bars being No11M). But other sources sources say it was a derivative of Phazotrons Koypo desighn, this seems pluasible as I have only ever seen one modern small NIIP radar and that was the Osa which is listed quite specifically as being for the Mig21 and the Mig29UBT, whereas the Koypo has a number of applications and phazotron says it is suitable for protecting the rear hemisphere of some aircraft.

Anyone know the answer?