Broadcom is suing Qualcomm for patent infringement and asking for a halt to the manufacture and sale of Qualcomm chips.

Two suits, filed in California, allege that Qualcomm has infringed a total of 10 Broadcom patents. Broadcom has also filed a complaint with the US International Trade Commission (ITC), seeking to ban the import of some foreign-manufactured Qualcomm products that it also claims infringe Broadcom patents.

Broadcom is one of the world's largest vendors of communications silicon. It supplies chips for a wide variety of wired and wireless communications systems, including cellular and VoIP as well as cable, satellite, DSL and LAN and carrier infrastructure.

Qualcomm on the other hand pioneered CDMA and develops chipsets for the cellular technology.

Broadcom said it is seeking unspecified monetary damages from Qualcomm and a permanent injunction to ban the manufacture and sale of its core baseband and RF chips, including chips for multi-media and for the QChat VoIP technology, which is used for cellular push-to-talk systems.

In its complaint filed with the ITC on Thursday, Broadcom alleged Qualcomm has engaged in unfair trade practices by importing chips and other products that infringe five Broadcom patents. It wants the agency to investigate Qualcomm and ultimately issue an exclusion order to stop imports of those products into the US, as well as a cease-and-desist order to stop further sales of the allegedly infringing products, according to the statement.

On Thursday morning, Qualcomm had not yet seen a copy of the lawsuits and was unable to comment, a spokesman said.

The patents at issue involve a variety of technologies for multi-media mobile phones, said David Rosmann, vice president of IP litigation at Broadcom. Those technologies include QChat, digital video encoding and decoding, simultaneous voice and data transmission and the use of Bluetooth along with cellular, along with ways to conserve battery life.

Broadcom believes one of the patents involved in the case is central to WCDMA (Wideband CDMA), the technology at the core of one of the major 3G cellular systems, and possibly to the other major 3G system, CDMA2000, Rosmann said.

One of the lawsuits involves the five patents that will also be considered by the ITC, Rosmann said. That case most likely will wait for a decision by the ITC, which generally acts more quickly than the federal courts, he said. Broadcom expects the ITC investigation to begin in late June and a hearing to be held early next year.

The other case, involving a different set of patents, will go forward in the court immediately, he said. Qualcomm has 20 days to respond to the complaint or may request an extension to do so, Rosmann said. He expects the case to go to trial in late 2006 or early 2007.

Broadcom's move indicates how important these technologies will become as multi-media capabilities such as video, music and messaging are combined with voice on advanced mobile phones, said IDC analyst Celeste Crystal.

"This is valuable [intellectual property] because they know that in the 2007-2010 time frame, this is where it's all going," she said. "Companies like Broadcom and Qualcomm are going to be key players in this battle that's shaping up over the next few years."