Crossing the Line With Wireless

By now, you are probably fairly comfortable with the various flavors of 802.11: a, b and g. But if you think that’s all you’re going to need to know about wireless, think again.

Other standards with which you’ll soon become familiar are better known by name than by number: WiMax, Zigbee and Ultra Wide Band (UWB).

Many of their potential applications will blur all the traditional lines between wireless LANs, RFID, cell phone communications and telemetry. But that’s the good news.

The only bad news is that most of these products are not already widely available for you to use.

Let’s start with WiMax. Just as WiFi (802.11) has allowed companies to use wireless LANs more easily and in more places — and has been built into many portable computers and laptops — WiMax has the potential to break down the walls between the warehouse and the outside world. The major advantage to WiMax is range: upward of 30 miles. (Think of the positive impact that would have on your access point budget.)

Admittedly, WiMax will be more limited within a four-wall environment and is primarily being viewed as a possible competitor to copper-based landlines. Still, WiMax could offer the possibility of turning an entire warehouse or yard into one gigantic “hot spot” with a single antenna.

Intel is planning on incorporating WiMax into a future generation of microprocessors, just as they have incorporated WiFi into the Centrino line. Even before that happens, however, we’ll see USB and PC-card WiMax radios becoming more commonly available.

And, based on the way WiFi has moved into airports and coffee shops, as WiMax is rolled out, it’s possible that, given rigorous security systems, you (or more importantly, your salespeople) could access warehouse data from virtually anywhere without having to search for a dedicated “hot spot” or dial in via cell phone.

Ultra Wide Band is another wireless technology that’s showing signs of providing applications besides wireless communications. UWB can be thought of as a sort of wireless Morse code, employing pulses of radio energy rather than a modulated carrier wave. Initially of particular interest to the military because of its low probability of being detected or intercepted, multi-path immunity, high-data throughput, and precision ranging and localization, these same features would make UWB useful in many commercial applications.

Several different versions of UWB are being explored that will offer voice and data communications at up to 25 Mb/s over a range of one to five miles on land. One interesting aspect of UWB is its ability to transmit sensor data from within sealed freight containers.

ZigBee is at the opposite end of the spectrum from WiMax and UWB — literally and figuratively.

Designed to offer low data rates and short range, you might wonder why ZigBee is of any interest at all. The answer is: low power consumption and self-organizing networks. While some see ZigBee, as a low-frequency technology, as a competitor to Bluetooth and other short-range, personal area networks, researchers see it as a way to link dozens (or thousands) of miniature sensor-based devices to measure temperature, humidity or vibration.

Although the range of self-powered ZigBee devices is not intended to be great, each device can act as a repeater, passing data from and to any other device within range. In this way, you can think of ZigBee communication as a pebble dropped in a pool of water with the data rippling out in all directions.

Theoretically, with enough readers dispersed around the area, the exact location of the initial data source could be determined — just as with current real-time locating systems (RTLS).

While ZigBee radios are currently available, tiny sensor-based devices aren’t.

For companies that want to monitor — or record — temperature and humidity, there is currently a sensor-enabled RFID system that will do just that. While it’s true that conventional methods could be used to monitor temperature and humidity in a relatively large area, the use of RFID allows specific placement — and precise readings — within a storage facility without the need for wiring.

While a lot of this technology is still just over the horizon commercially, it’s coming on fast. Put it on your radar screen now.

Bert Moore, contributing editor

[email protected]

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.