Hitting out at the telecom ministry for not listening to its concerns, the Cellular Operators Association of India (COAI) on Wednesday dismissed the present spectrum allocation system as ‘‘discriminatory’’ against GSM technology and the reason behind ‘‘high’’ tariffs.COAI Director General T.V. Ramachandran said on Wednesday that GSM operators were paying 4 per cent of revenue as spectrum usage charges, while CDMA operators were paying 2 per cent, for the same number of subscribers.‘‘Since the Average Revenue Per User is approximately the same for GSM and CDMA, it is irrational, illogical and unfair to impose a double spectrum levy on the GSM players and their consumers,’’ Ramachandran said.He complained that DoT and its spectrum committee were not addressing the GSM industry’s concerns, despite ‘‘months of ongoing submissions.’’Another ‘‘serious discrimination’’ pointed out by COAI deals with the number of cellsites that GSM and CDMA operators have set up.Ramachandran said going by Communications Minister Dayanidhi Maran’s statement in July that operators must invest in infrastructure to make efficient use of spectrum, CDMA operators are ‘‘grossly under-utilising’’ their allotted spectrum.‘‘As per present spectrum allotment criteria, CDMA operators were permitted to get away with 50 per cent utilisation by setting up less than half the cellsites as compared to GSM,’’ Ramachandran said.