India’s Economic Times is reporting that mobile operator Tata Teleservices Maharashtra (TTML) is preparing to launch GSM-based services in the Mumbai circle. TTML already operates in the region over CDMA infrastructure, but plans to launch GSM services are underway as part of a nationwide GSM rollout strategy by the cellco’s parent, the Tata Group. The Tata Group has already launched GSM services in Chennai, Tamil Nadu, Karnataka and Andhra Pradesh through Tata Teleservices (TTSL) under the Tata DoCoMo banner. It is understood that a significant portion of TTML’s GSM infrastructure sits on top of its existing CDMA network, with the same towers hosting both services in many locations. TTML is also expected to complete its GSM rollout across Goa and the rest of Maharashtra by the end of this month.