Verizon Wireless Inc. plans to announce today a new high-speed data service in the Washington area that would allow mobile users to connect to the Internet at speeds as fast as or faster than those provided by cable or telephone wires.

The Evolution Data Only (EvDO) network will allow users of compatible wireless devices to download large files such as spreadsheets, inventory lists and even video in a matter of seconds while on the go. Verizon Wireless plans to launch the service in the late summer, with coverage initially limited to an area inside the Capital Beltway. The service will also be launched in San Diego around the same time.

A working EvDO network will be a major step toward the establishment of long-awaited "third generation" wireless technology. Wireless companies have promised for years that "3G" networks would transform wireless communication by taking it beyond voice, text messages and still photos.

"I view this as Verizon Wireless putting a bold stake in the ground for what will ultimately become wireless multimedia services," said Scott A. Ellison, director for mobile wireless at IDC, a Massachusetts-based technology research firm.

Ellison noted that EvDO technology is already popular in South Korea, where consumers use it for tasks from video conference-calling to watching television on their cell phones. "It is blazingly fast," he said.

During preliminary tests that Verizon Wireless conducted in an area from Falls Church to Rockville, people could download files while on the go at speeds from 300 to 600 kilobits per second, or about five to 10 times as fast as a dial-up modem. While stationary, users could access the Internet at speeds up to 2.4 megabits per second, about 60 percent faster than a cable modem.

Verizon Wireless offers a nationwide wireless network that offers speeds about two or three times as fast as a regular dial-up connection, but those rates are too slow to download large business files.

The company will begin selling EvDO-capable cell phones and special cards for laptop computers and handheld organizers that will enable them to work with the EvDO network. It declined to comment on prices; a spokeswoman said the initial target market will be business customers.

The EvDO system in the Washington area is to use equipment developed by Lucent Technologies Inc. The San Diego network will use similar equipment developed by Nortel Networks Corp.

One barrier to rollout of EvDO has been that the technology requires wireless companies to set aside valuable airwaves just to carry data. Verizon late last year bought a large slice of airwaves in 50 markets for $750 million, in part to make room for services such as EvDO. But most mobile phone companies are scrambling for enough spectrum just to cover their growing number of regular wireless phone subscribers, so it may take several years for EvDO to become widely available across the country.

The EvDO network will be carried over Verizon Wireless's existing cell towers, which have been updated with new software and circuit boards. Users will be able to access private corporate networks using secure connections.

Monet Mobile Networks Inc., a small firm in Kirkland, Wash., rolled out a stand-alone EvDO network in October in seven Midwestern markets, including Sioux Falls, S.D., and Duluth, Minn., where there is limited access to high-speed, wired networks.

Also today, Verizon Wireless plans to announce its intention to provide wireless networks at 475 hotels and 10 airports around the United States using a technology known as WiFi, for wireless fidelity. WiFi is more limited than EvDO, as users must be within 300 feet of a local base station. It has become an increasingly popular way for wireless users to access the Internet in hotels, airports and coffee shops around the country.