Wireless USBs

Unwiring the USB

There are no strings attached anymore to your USB. Wireless USB has finally been accepted as a standard, and the first lot of products is already out

Monday, September 10, 2007

USB is officially untethered now. What allowed you till yesterday to plug in your digicam, MP3 player, or any other hardware device, now requires you only to place your device within a definite radius around your PC, to perform the same USB functions. In other words, you no longer need a wire running to your PC. Thanks to Wireless USB (WUSB).

According to Universal Serial Bus-Implementers Forum (USB-IF), Wireless USB is the first wireless personal interconnect technology, which is backward compatible with wired USB, and allows users to connect up to 127 devices, and promises a bandwidth of up to 480 MBps at a range of 4 metres and 110 MBps at 10 metres. It is based on the WiMedia Alliance Ultra-Wideband Common Radio Platform, and its development began in February 2004, with the formation of the Wireless USB Promoter Group, which consisted of Agere Systems, HP, Intel, Microsoft, NEC, Philips Semiconductors, and Samsung. A year later, the Wireless USB specification was completed and in June 2006, the USB-IF carried out its first ever demonstration of the WUSB, using an Intel host adapter, by transferring a HD video from a Philips wireless semiconductor system, using an XP OS.
Though not directly, WUSB has a connection with the WiMedia Alliance, a body that regulates and sustains interoperability of Ultra-Wideband (UWB). Presently, WUSB uses UWB platform, while other protocols like Bluetooth are expected to follow soon.

In the same league
The obvious comparison for WUSB would be with Bluetooth and WiFi, and though one might like to believe that all three are doing the same thing, the idea of WUSB is to provide a high bandwidth protocol. It works for a shorter range than WiFi, but with higher transfer rate than Bluetooth, which works on the same 2.4 GHz radio device. Subtly put, the idea of WUSB is to trace the middle path between Bluetooth and WiFi.
Interestingly, the only other company that has embarked into the WUSB space is Motorola powered Freescale Semiconductors, with its offering called Direct Sequence UWB, which transmits a series of low power pulses at frequencies in the range of 3.1 GHz to 10.6 GHz. However, no manufacturer has begun making products that use this protocol yet.

The most important element of WUSB is the Micro-scheduled Management Command (MMC) that helps 'seek and find' a Wireless USB cluster (a virtual wireless network formed by wireless devices found in the area), understands its working, manages power, and schedules data transmissions as fast as possible. WUSB also contains a UWB information frame, with multiple elements, each taking care of a particular function. Unlike USB, WUSB does not use the Start of Frame (SOF) mode of sending information as packets to the device for synchronization. In turn, it uses MMC to transmit information queries to the connected devices at regular intervals.

Looking back
Wireless USB, in a way, is a product of natural progression that was to happen sooner or later. What began as a first generation plug-n-play system that operated at a speed of 12 mbps, morphed in 2000, into a high performance data transfer mechanism called USB 2.0, which currently delivers up to 480 mbps�a 40 fold rise in data transfer rate. USB exterminated a term called 'parallel port' from the hardware engineer's dictionary, and most peripheral devices chose to make do with this system, offering their products in only the USB compatible format. More than anything, it was the printer manufacturers who embraced USB the most, besides lifestyle portables. The next obvious graduation would be to make these devices 'talk' to your PC or laptop wirelessly.

First line of products featuring wireless USB (clockwise)-Lenovo Thinkpad T61, D-Link USB 4-port hub, IOGEAR USB hub with adapter kit, and Dell Inspiron 1720

Compatible products
Coinciding with the official launch of WUSB, the USB-IF announced a list of hardware products that passed its compliance and certification tests. Dell's Inspiron, and Lenovo's Thinkpad have been the first to incorporate WUSB to their machines, with D-Link and IOGEAR being the first to create connectivity hardware. This includes Dell's Inspiron 1720, priced upwards of $900 internationally, which is powered by Intel's Core 2 Duo T5250 chipset, an anti glare 17 inch display and a 120 GB SATA hard drive. The Thinkpad, however, seems to be getting a bad reputation of a 'station wagon' since it's a little bulky for its class, but claims to be the first to incorporate WUSB compatibility. It gives customers the option of choosing an Intel or nVIDIA graphics card, and is positioned as a business-only machine.

On the other hand, D-Link's wireless adapter and hub has an interesting concept to back it . hub is essentially something which allows you to connect multiple devices with it. The adapter, however, has a flip that you open and plug into the USB socket of your PC or laptop, after which it wirelessly syncs up to the hub, in turn connecting with any device found in the range of 30 metres.

Adoption
These devices are only the initial handful to embrace WUSB. What one can really expect here to find many applications around WUSB coming up, in a few months. Take Bluetooth for instance. What began as a short-range mode of communication between two devices, Bluetooth saw itself being known as the mobile connectivity technology. An estimated 600 million Bluetooth devices were shipped world over in 2006 according to a survey conducted by the Bluetooth Special Interest Group. Now picture a technology that communicates with your mobile device 500 times faster than Bluetooth, and works more efficiently at shorter ranges. All we need for that to happen is somebody out there to sync up WUSB for mobile applications. This is assuming that the upcoming models of digicams, music players, printers and other hardware devices will come with WUSB compatibility.

The road ahead
For now, the biggest compelling thing that stands out is the fact that Wireless USB is backward compatible. According to a survey conducted by corporate analysts, In-Stat, there are 11 million wireless devices in the world today, and this number can easily be expected to double, by 2010. In absence of WUSB, it would simply mean so many more wires, crisscrossing each other and creating one big jungle of wired devices. The way things are going currently, WUSB is well capable of becoming a standard every hardware manufacturer swears by, and in the long run, may reduce manufacturing costs as well.

But data errors could still be a concern, especially if the information packets are bigger, and if you try to send it to the last mile। Anyways it still scores over the wired USB for which the range is zero.

P.S: This article has been taken from PC-QUEST.. Hope all of you enjoy it...