A new version of the Bluetooth wireless standard was previewed at the Bluetooth Congress this month, and vendors appeared increasingly confident about the technology's future in consumer and corporate hardware. However, there are still concerns regarding usability and interoperability if customers use Bluetooth equipment from multiple vendors.

Bluetooth version 1.2 is still being tested and is not likely to be ratified before November at the earliest; and the first Bluetooth 1.2 products are not expected until March 2004, according to experts.

The 2003 Bluetooth Congress in Amsterdam differed from previous events in that there was an air of maturity about the standards work and products.

Interoperability problems have been considerably reduced, but the goal of guaranteed interoperability between products is not yet achieved. Mike McCamon, executive director of the Bluetooth Special Interest Group (SIG) that controls the Bluetooth standard, said he is keen to fix this and has appointed a full-time "interoperability czar".

Some users are confused about Bluetooth profiles, which specify how devices work with each other. A Bluetooth headset, for example, would be expected to work with a phone that uses the headset profile, but what about the profile for hands-free equipment? To tackle this problem, McCamon said that the SIG may set up an online database listing products which are compatible with each other.

The forthcoming Bluetooth 1.2 standard adds adaptive frequency hopping (AFH) to improve tolerance to interference, especially when close to 802.11b wireless LAN (WLAN) kit that shares the same 2.4GHz portion of the radio spectrum. There are also improvements to quality of service for voice functions. Bluetooth version 1.2 supports multiple simultaneous connections - which will enable a user to take a call using their Bluetooth headset while their phone is synchronising with their laptop.

The old problem of Bluetooth co-existing with WLANs has been addressed, and there are new adapter cards offering Bluetooth and WLAN on the same module. Some industry experts predict that within a year, most new WLAN cards will also support Bluetooth.

Several vendors are now shipping their second- or third-generation Bluetooth headsets. Plantronics now offers eight hours of talk time and 200 hours on standby with its M3000 headset, which matches most mobile phones. Cambridge Silicon Radio's (CSR) new Bluecore3 range offers single-chip solutions for headsets and other applications at low cost.

The next big Bluetooth application will be in the mouse and keyboard market, according to chip firm Broadcom. This would remove cable clutter around desktop PCs and make text entry easier in PDAs and mobile phones.

The firm has developed a low-power Bluetooth chip that replaces all the circuitry in a keyboard or mouse, which should mean that future Bluetooth peripherals will cost little more than current wired designs.

TDK announced a range of products called Blu2I that make it easy for hardware vendors to add Bluetooth to existing products. These are modules with a built-in Bluetooth stack that plug into host equipment via industry-standard interfaces and protocols such as RS-232 serial.

Sony gave an impressive demonstration of a proprietary extension to Bluetooth, named Feel. When two Sony products with this technology are within wireless range, they will recognise each other and connect automatically. This makes the products easier to use, but raises the question of how such proprietary extensions can be allowed without harming interoperability with other vendors' products.