India on Tuesday allowed telecoms operators to share transmission systems, radio access networks and antennae and simplified the approval process for building mobile towers.But radio spectrum, or air waves used for wireless networks, cannot be shared. Telecoms operators in India were earlier permitted to share only passive infrastructure such as mobile towers, buildings and power backup facilities. Sharing infrastructure reduces the operating costs and capital expenditure of wireless telecoms operators, allowing them to maintain margins in a competitive market that has call rates as low as 1 U.S.