Sprint Nextel Corp., which has struggled to attract customers with marketing criticized as confusing and unfocused, will try again when it begins rolling out a new round of advertising this weekend.

Gone are the gimmicks of the past, such as the face-slapping cowboy, the businessman threatened by vultures or the guy from “Office Space” talking about the company’s wireless network warding off meteors.

In its place is network speed as art – performers using streaming lights to build mid-air flowers, rocket ships and pie charts as announcers talk about the instant gratification of mobile technology.

“We wanted to celebrate our magical network speeds,” said Michelle Emerson, vice president of brand for Reston, Va.-based Sprint Nextel, which has operational headquarters in Overland Park. “It’s a metaphor for Sprint’s advanced technology.”

Using the tag line “Sprint Ahead,” the eye-catching ads, which will be unveiled in movie theaters Friday and begin airing on television Sunday, are another attempt by the company to use its fast wireless download speeds to separate itself from key competitors Verizon Wireless and AT&T, which have focused their marketing on network reliability or specific devices, such as AT&T’s iPhone.

“This talks about how customers can get what they want right now,” said Emerson, whose company developed the campaign with the help of San Francisco-based Goodby, Silverstein & Partners. “We believe it will really break through the clutter.”

Emerson said the initial ads would get consumers to see speed as important, and subsequent ads would show how Sprint Nextel’s network and devices could make that speed work for them in terms of music and movie downloads and instantaneous Internet browsing.

“From that aspect, it will give people the idea this is how Sprint will impact my life, and that’s what was missing before,” said Roger Entner, senior vice president of the communications sector of New York-based firm IAG Research, who has seen the new ads. “It’s more tangible than the abstract of ‘It’s more powerful,’ and making it more tangible to the potential customer makes a big difference.”

Sprint Nextel also plans ads that focus on the Nextel-branded press-to-talk devices favored by construction crews, taxi services and other business users.

The new campaign comes at a critical time for the company.

Last month, Sprint Nextel reported gaining just 600,000 new subscribers in the first quarter, compared with 1.2 million and 1.7 million, respectively, for AT&T and Verizon. With the number of people without a cell phone shrinking fast, some of those gains came at Sprint Nextel’s expense.

Sprint Nextel also said it had lost 220,000 high-quality customers who pay their bills at the end of the month and typically spend more, the third straight quarter of postpaid losses.