Vodafone on Thursday said there will be significant improvement in call drop issue in Delhi within 12-16 weeks as it plans to put up more sites as well as augment capacity of the existing ones. In the last 6 months, Vodafone has put up over 500 sites in Delhi, while capacity of existing 550 sites have been augmented. “As an operator, my sense is that in next 12-16 weeks, you will see clear tangible difference in call drops and overall voice quality,” Vodafone Business Head (Delhi) Apoorva Mehrotra told agencies.