A Wi-Fi startup is promising technology that could boost range by 75 percent and reduce interference.

Cohda's signal-processing technique that helps handle multi-path interference, which comes when signals take multiple paths to reach the receiver. The technology, which Cohda will license to OEMs, increases the sensitivity of receivers, helps to maintain non-line-of-sight radio links with mobile clients, increases the reliable transmission range by 75 percent and minimises interference, the company claims.

The technology address challenges arising from the characteristics of the modulation technique used in 802.11g and 11a, and in WiMax - orthogonal frequency division multiplexing. Reflected signals, called multipath, can create slight delays at a receiver. If this delay exceeds 40 microseconds, the receiver starts to drop packets, says Martin Suter, Cohda's chief executive.

Till now, the solution has typically been to compensate for multipath interference and the drop in performance by adding more nodes - and therefore more cost and complexity - to a mesh network. Cohda has created digital signal-processing code, which lets the radio receivers compensate for the spread.

The product's details will remain mysterious until it is formally announced later in 2006, but Cohda is in talks with several OEMs, said Suter. The company, founded in August 2005, has about $5 million total investment.