A host of hardware and software companies are addressing current shortcomings in wireless location services.

A study of the real-time location-services market by the Yankee Group classified two groups of vendors, nearly all of them small. One group, including WhereNet, Radianse and RF Code, typically uses unlicensed lower-frequency spectrum, though WhereNet does have products that use the 2.4-GHz band. The second group, which includes AreoScout, Ekahau, Newbury Networks and PanGo, uses the 2.4-GHz band and their radios are based on the IEE 802.11b/g wireless LAN standard.

Several vendors in the second group are exploiting Cisco's release last year of the 2700 Wireless Location Appliance. It's a rack-mounted box that can collect location data on wireless tags and client devices through as many as 1,500 access points in a wireless LAN. The appliance has a set of APIs used by companies like PanGo to extract the raw location data into their own applications.

The software infrastructure is becoming more substantial as well. Earlier this year, for example, Newbury Networks revamped its underlying location software to create what it calls the Newbury Presence Platform. The server software includes services, such as being able to create an event and an event alert when a tagged asset moves, and a set of programming interfaces to link with other applications that make use of the location data.

Another change uncoupled the platform from Newbury's own brand of wireless sensors: now it can work with third-party access points.