Airgo Networks said Wednesday that the company is sampling its third-generation router chip at speeds that surpass a typical wired Ethernet connection.

Airgo’s third MIMO (Multiple In, Multiple Out) chipset is sampling now to router manufacturers, who are expected to have products on the market by the fourth quarter, Airgo said.

Enhancements to the core architecture will push wireless transmission speeds up to a theoretical limit of 240 Mbit/s; Airgo internal tests have achieved transmission speeds of 120-Mbits/s, faster than the 100-Mbit Fast Ethernet found on the majority of the world’s PCs.

Like a modern personal video recorder, the new MIMO chipset integrates two distinct radios, giving the two-chip chipset the ability to communicate data on two different channels. An array of antennas added by the router manufacturer then receives and transmits the signal, varying the power to “focus” on the transmitter or receiver. The Airgo chipset uses a technology called “Adaptive Channel Expansion” to expand the breadth of its signal without interfering with other signals.

“When MIMO was first unveiled it reversed over 100 years of scientific thinking by harnessing natural radio wave distortions, which were previously perceived as interference, to deliver dramatically increased speed, range and reliability,” said Greg Raleigh, president and chief executive of Airgo Networks, in a statement. “With True MIMO Gen3 technology our team has achieved a scientific milestone by proving that wireless can surpass wired speeds.”

Current Airgo customers include Belkin, Buffalo, Linksys, Netgear, Planex, Samsung, Smartvue and SOHOware.

Airgo’s MIMO technology is a key component of the ucoming 802.11n specification, although the company has stopped characterizing the technology in that context. The next-generation “True MIMO” chipset, as Airgo calls it, is backwards-compatible with 802.11b and 802.11g radios.

The WWisE and TGn Sync groups battling over control of 802.11n apparently settled their differences earlier in August. However, a new report from ABI Research on Thursday indicated that the four top wireless chip providers may be out to sabotage Airgo’s progress, which has made an end run around the IEEE standards group.

“It was hoped that by now the two industry groups, WWiSE and TGn Sync, would have thrashed out a single proposal,” said Philip Solis, senior analyst, who covers Wi-Fi semiconductors for ABI Research’s Wi-Fi Research Service. “But we hear that four major companies — Broadcom, Intel, Atheros and Marvell, holding the lion’s share of the Wi-Fi chipset market — have formed a third camp with the aim of writing a whole new proposal.”

In light of this development, ratification of a standard could be delayed until mid-2007 at the earliest, Solis estimated. The group could end up forcing Airgo into redesigning its chipset, ABI analysts said.