Bluetooth: Under the enamel

The simple facts about Bluetooth are that in its present, Mark 1 version, it can exchange data with another Bluetooth enabled device at a maximum throughput rate of 750 kilobits (or just over 94 kilobytes) per second. Two further key characteristics are the small footprint of the chipset, which makes it suitable for mobile phones, and its low power output (one milliwatt).

Taken together, these three features mean that it is easy to embed in all kinds of products, from printers to headsets.

Intel, in its white paper on Bluetooth, cites figures from Cahner’s In-Stat Group to give an idea of just how many Bluetooth enabled devices the world is likely to see over the next year or so. The worldwide base of notebook computers stands at 79.9m and growing. In 2000 the number of cellular phone users was 600m, and this number is expected to pass the 1bn mark by 2003. The number of handheld computers is projected to grow to 34m by 2004. To this you have to add hordes of printers, desktop PCs, faxes and the armies of special purpose devices such as headsets, MP3 players, digital cameras and e-mail readers that are expected to appear.

All these items can be retrofitted with Bluetooth, and new products are already starting to come with Bluetooth already embedded. (Desktop PCs, for example, can be retrofitted with Bluetooth via the USB port.)

Multiple Bluetooth devices form a PAN once they have carried out the initial recognition process. However, in any session, one device acts as the master device for all the companion devices. It is responsible for controlling the communication because it selects the hop frequencies that govern the communication session. Bluetooth is a frequency hopping spread spectrum wireless technology. Tranceivers use 79 hop frequencies in the 2.4GHz band, at a rate of 1,600 hops per second, with one data packet sent at each hop. The frequency pattern is determined by an algorithm which the master device shares with each of the communicating devices.

This means that only those devices that have been selected to participate by the user can take part in the communications session, and provides Bluetooth with military level security “out the box”.

Bluetooth futures

The Bluetooth SIG is currently in the process of formulating Bluetooth Mark 2, known variously as Radio2 or Version 2. The main feature here is the throughput speed, which is expected to be as high as 10 Mbps. The chief driver for an enhanced Bluetooth with higher throughput speeds is clearly a perceived need for quality video streaming and video conferencing, where the 750 bits per second of the current generation of Bluetooth chips, is way too slow.

However, sceptics doubt that this standard will see the light of day since it moves directly into terrain already occupied by 802.11a, the enhanced version of the wireless LAN standard, which provides 22Mbps.

Proponents of Bluetooth, however, say that seeing the two as competing technologies is simply misguided and that Bluetooth Mark 2 will be a very useful tool in the solution provider’s toolbox, as and when it appears, possibly in 2004.

Market statistics

A recent report by Frost and Sullivan focused on the fact that early suppliers of Bluetooth chipsets were already on their second generation of products by the end of 2001. The supply side saw some consolidation through 2001 and Frost & Sullivan predicts that this trend will continue.

The entry of bigger players, such as 3Com, Texas Instruments and Infineon is already creating sufficient competition to drive chip prices closer to the sub $5 target.

In 2000 the average price of a Bluetooth chipset was $25, this fell to $15 by the end of 2001, and has come down further in 2002. Chipset shipments for 2001 amounted to 9.23m units, some 900% higher than in 2000, and accounted for some $138m in revenues. Frost & Sullivan is predicting that the number of chips shipped will rise to close to 1bn annually by 2006. Importantly, Frost & Sullivan argues that the industry now realises that there is no “one size fits all” solution. The Bluetooth SIG has developed new Bluetooth profiles to support new application types. The cell phone, currently the largest consumer of Bluetooth chips is expected to stay the dominant application through to 2005.

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