Sprint expands Puerto Rican EV-DO coverage

US mobile operator Sprint Nextel had invested USD28 million in network upgrades for its Puerto Rican unit by the end of September 2006, according to local newspaper El Nuevo Día. Recent investment has focused on expanding CDMA2000 1x network coverage to new parts of the island and improving its 1xEV-DO data network coverage and capacity to boost mobile data revenues.