Blue Streak
In most pro AV installations, the short-range wireless technology known as Bluetooth is relegated to mundane, low-bandwidth tasks such as enabling whiteboards. But a new version of the technology could make it practical for a wider variety of applications, including HD video.
Can you find me now?What price speed?Wired gets wireless
In most pro AV installations, the short-range wireless technology known as Bluetooth is relegated to mundane, low-bandwidth tasks such as enabling whiteboards. But a new version of the technology could make it practical for a wider variety of applications, including HD video.
CSR’s BlueCore4 chipset uses the latest version of Bluetooth wireless technology, for speeds of up to 3 Mb/s. But a new version of Bluetooth, due out in 2007, will hit 480 Mb/s, making it a potential fit for a variety of pro AV applications.
In late March, the Bluetooth Special Interest Group (SIG) announced that it had begun developing a next-gen version that will be significantly faster than the 3 Mb/s that the technology currently supports. Just how much faster depends on a variety of factors, including what the SIG member companies agree to as they finalize the new standard.
“It will depend on range, but probably 480 Mb/s for close connections,” says Mike Foley, executive director of the SIG, which is based in Bellevue, WA. “We think that for battery-operated devices, 100 Mb/s is the sweet spot.”
Even at the low end, that’s enough bandwidth for an HD video stream, plus any control channels for background communications between devices. By comparison, the fastest commercially available versions of WiFi — 802.11a and g — max out at 54 Mb/s, with only about half of that bandwidth available to the application itself. (A forthcoming version, 802.11n, promises at least 100 Mb/s.)
Next-gen Bluetooth will get its speed boost by incorporating techniques from a once-rival technology called ultrawideband (UWB). Like Morse code, UWB uses brief pulses of energy to transmit data at speeds of 100 Mb/s or more. That approach also makes the UWB signal more resistant to physical obstructions, such as walls. Both UWB and Bluetooth have a range of about 33 feet, although they can be souped up to travel greater distances.
The SIG is using a version of UWB developed by the WiMedia Alliance that delivers up to 480 Mb/s. That trumps 802.11n, which initially will deliver about 100 Mb/s but could hit 600 Mb/s in later versions of the standard.
Although speed is a plus because it enables bandwidth-intensive apps such as HD video, it doesn’t solve one of the main reasons why wired technologies are still more common in pro AV: the lack of a fast, easy way to connect devices, such as a laptop to a wireless projector.
Some vendors, such as Toshiba, have tried to streamline the connection process by providing client software for laptops that provides a radar-like view of available 802.11 equipment, including projectors. That approach helps, but until such solutions become the rule rather than the exception, wired technologies are likely to remain the preferred choice for connections. As one AV integrator told Pro AV in 2005, “If it were that easy to connect to a projector, then we’d be selling a lot more wireless systems.”
Bluetooth could provide the solution. When it was announced in 1998, the technology was positioned as a way to provide plug-and-play wireless connections between devices. Despite some fits and starts since then, Bluetooth has refined the process of “pairing” two or more devices — even if one of them doesn’t have a screen to help facilitate that task.
Next-gen Bluetooth builds on those techniques. “The goal of the work is to be able to leverage the existing search and service discovery mechanisms within a Bluetooth system,” Foley says.
Before next-gen Bluetooth becomes commercially available — sometime in 2007 — the SIG will release another version that provides additional connection aids. That could help make next-gen Bluetooth a good fit for pro AV. “It has some enhancements so that you’ll be able to securely pair devices without having to type in PINs,” Foley says. “That will be easier for devices that don’t have a rich user interface. That will be very applicable to AV devices.”
If Bluetooth has one thing going for it, it’s incumbency. At the end of 2005, the technology had a worldwide installed base of more than 500 million products, according to the SIG. By the end of 2006, the SIG expects the installed base to top 1 billion. Although the bulk of those are in consumer products such as cell phones, those volumes are still worth noting because they help drive down the cost of chipsets — currently about $3. That improves the business case for using Bluetooth in pro AV products.
The wild card is the premium that next-gen Bluetooth initially will bear simply because it’s new. Until next-gen Bluetooth chipsets begin shipping in high volumes, their cost is likely to remain high — a disincentive for vendors that want to add the technology to their products but can’t because doing so would increase their price.
Just how much of a premium remains to be seen. “When they first come out, they’ll be more expensive than Bluetooth 2.0 + EDR chip, which is the current spec,” Foley says. “Over time, that will drop. I don’t think that they’re going to be astronomical. I don’t think that they’re going to be the prices that you saw when Bluetooth first came out in 2000.”
Another variable that will affect the cost and volume of next-gen Bluetooth is the need for bandwidth. Today, Bluetooth is used primarily for low-bandwidth applications such as connecting a headset to a cell phone. So unless those applications suddenly develop a need for the speeds beyond what Bluetooth currently delivers, there’s little incentive for vendors or users to prefer the next-gen version. As a result, next-gen Bluetooth may take a long time to achieve the same product volumes — if ever.
“I don’t think that it’s a 100-percent overlap,” Foley says. “A device such as a headset wouldn’t need a high-speed channel.”
Resources
For more information about wireless in AV, check out:
- Bluetooth Special Interest Group – The SIG’s websites at www.bluetooth.org and www.bluetooth.com have details about standards work and product availability.
- Ultrawideband Forum – The association’s website at www.uwbforum.org includes technical information and standards updates.
- WiMedia Alliance – The association’s website at www.wimedia.org features information about WiMedia UWB, as well as work to make it interoperable with 1394, Wireless USB, and Bluetooth.
- UStec’s Wireless Wallport – A detailed description is available at the U.S. Patent Office’s website at www.uspto.gov/patft/index.html. Search for patent No. 7,027,431.
- What’s Wrong With Wireless? – Unreasonable expectations, technical hurdles, and security issues have prevented wireless projection from going mainstream. Are we any closer to a solution? May 2005
- Speed Isn’t Everything – Next-gen WiFi will be faster and more reliable, but wireless is likely to remain a bench-warmer rather than a starter, October 2005
- Ultra Wideband Doubles the Speed of WiFi – Still at least one year away from its commercial debut, ultra wideband could supplant WiFi for wireless dominance, August 2003
Despite an installed base of 500 million products and counting, Bluetooth isn’t ubiquitous. Nor is any other wireless technology, including 802.11 WiFi. Hence the appeal of a wireless product that leverages existing technologies.
That’s the strategy behind the wireless wall-port, which attaches to a Cat5 cable and uses a variety of wireless technologies to transfer the signal to devices such as projectors and displays. Patented in April by UStec, a Rochester, NY-based maker of networking products for AV, the wireless wallport is nestled inside a box that replaces the Cat5 jack wall plate. Initial versions of the wallport would use one of several wireless technologies: 802.11a, b, g, or n, IEEE 1394, or WiMAX. “We’re working on multimode devices,” says Bill Thompson, president of UStec.
The wallports probably would communicate with AV devices via a converter box that plugs into one of their existing connectors. “We can build converter boxes, and we might have to do that,” Thompson says. “The ideal solution is to have the vendor build it right in.”
The wallports are still at the R&D stage, so pricing hasn’t been set. “We want this to be very affordable,” Thompson says. “We don’t want this to be a high-end unit that costs $400 to $500 per node. We’d love to get it out to the installers at under $200 and maybe even half that.”
With 802.11, one issue for AV pros is managing channels to avoid interference, which hurts signal quality. For wallports that use 802.11, UStec plans to tackle that issue through software, although the company won’t say exactly how because some of the techniques are proprietary. “Our objective is to make it as simple as possible for the installer,” Thompson says. “We’re working on software to automate as much of that as possible. We’ve been in the industry long enough to know that the products are successful only if they’re successfully installed.”
With wireless, one key to a successful installation is ensuring that walls don’t knock down the signal to the point that audio or video quality suffers. UStec aims to address that issue by using wireless only for the signal path’s final leg rather than the entire link.
“With this approach, we’re taking wireless right into the locality, where you need it,” Thompson says. “The more that you can avoid going through walls, the better the results for the installer.”
