NEW YORK (CNNMoney.com) - Warner Brothers and CBS Corp. announced plans Tuesday for the creation of a new broadcast television network, called CW, that would replace the WB and UPN networks in the fall of this year.

The new broadcast network will draw on programming from both WB and UPN, and will be a joint venture between Warner Bros. and CBS (Research), with each company owning 50 percent, officials of both companies said. (The "C" stands for CBS, the "W" is for Warner.)

"This new network will serve the public with high-quality programming and maintain our ongoing commitment to our diverse audience," said Les Moonves, the chairman of CBS, in a statement (see video).

Prime time programming will target the profitable 18-34 age group, officials of Warner and CBS said.

The new network will broadcast such UPN shows as "America’s Next Top Model" and "Veronica Mars," as well as WB programs "Beauty and the Geek" and "Smallville."

In addition, World Wrestling Entertainment’s "Smackdown," which has been a mainstay at UPN, is expected to play a role in the schedule. The new fall line up is expected to be announced in May.

UPN and the WB have struggled to attract viewers from the four established networks since they were launched in the mid-1990s. But each has its strengths.

The WB has had some hits throughout its history, particularly with younger audiences, having done well lately with shows such as "Smallville" and "Gilmore Girls."

UPN has recently gained some critical acclaim and strong ratings for its sitcom "Everybody Hates Chris," which airs on Thursday nights and fared well against shows such as NBC’s "Joey" and Fox’s "The O.C."

Both networks will cease operations in September, broadcasting their respective network schedules independently until then.

Dawn Ostroff, currently president of UPN, will become president of entertainment, and John Maatta, currently chief operating officer of the WB, will become chief operating officer of the CW.

The new network will employ a lot of the same people, "but there will be one person where there used to be two," said James Goss, an analyst with Barrington Research, suggesting that there may be more executive jumbling throughout CW in the works.