Sprint Nextel Corporation on Monday launched its long-awaited next-generation 4G wireless broadband services based on WiMax technology in Baltimore, Maryland, marking its first step towards the planned nationwide rollout of its Xohm service, a low-cost wireless broadband internet access with speeds similar to fixed cable and DSL lines.

The service, which promises an average data download speeds of between 3Mbps and 5Mbps (mega-bits per second), is offered at charges much lower than its rival cellular data plans, with an optional introductory services packages including a $10-a-day pass and a $30-a-month plan for mobile access.

The US mobile network is slated to launch similar services in Washington, DC and Chicago by the end of the year and has already started working on the infrastructure needed to support services in a number of other markets, including Boston, Philadelphia and Dallas/Fort Worth.

The service launch is viewed as a strong move from the company to fight back the fierce competition thrown by rivals like AT&T''s mobile unit and Verizon Wireless.