Understanding the WUSB (Wireless USB)

The WUSB (Wireless USB) is a wireless USB version, which uses the UWB system for data transmission to short distances, using low-power signals. In theory, the WUSB supports transmission rates of up to 480 megabits at distances up to 3 meters and 110 megabits up to 10 meters.

As the signal uses a very low power, WUSB is suitable to connect devices within the same environment (the same room or Office, for example), without significant impediments between them.

The goal is that the WUSB is an option to use in all kinds of USB peripherals including mice, joysticks, printers, scanners, digital cameras, mp3players and even external HDs.

The rates of 480 and 110 megabits disclosed are transmission rates “brutal”, which do not include the losses caused by the transmission protocol, error correction, signal attenuation and so on. The rates obtained in practice, especially at distances greater than 3 or 4 meters is much lower, so that, in terms of speed, the WUSB doesn’t compare directly to USB 2.0.

Despite this he makes the question of practicality and “cool factor”, since it allows you to download photos from the camera, or copy songs to mp3 player without having to first connect them to the PC. There is also the possibility to connect directly to another device, allowing the camera to print photos on the printer, or the mp3 players touch songs stored on an external HD, for example. Just as in the USB, it is possible to connect up to 127 devices.

In addition to devices with native WUSB transmitters, there are two types of adapters. The first is a transmitter that allows PCs without transmitters to communicate with WUSB devices. It is similar to a USB or bluetooth adapter, which you plug into an available USB port and it’s called WHA.

The second is a kind of “hub” (called WDA), intended to connect USB devices to your PC with the transmitter. You could connect your USB printer on the WDA and so access it from your PC with a transmitter WUSB.

There is also the possibility of joining a WAH and a WDA, creating a kind of wireless USB hub according to nampabuyer. Until the motherboards, notebooks and other devices with transmitters WUSB become popular, this is probably the only class of wireless USB products that you’ll see for sale. An example is the Belkin Cable-Free USB, one of the first products of the new crop:

It includes a WDA with 4 doors and a WHA to connect on the PC. Once installed, it creates a wireless link with the hub, so that any device plugged in it is accessible from your computer. It’s not the kind of thing you would kill to have, but it opens some interesting possibilities. You no longer need to leave your USB printer and scanner next to the micro, for example, you can put them anywhere in the environment.

This chart, supplied by Belkin, shows the expected performance for the different classes of WUSB devices:

At the top are the 480 megabits “raw”, which are never achieved in real situations, due to a number of factors. At the second level are the USB 2.0 wired controllers, that affect real rates around 270 to 320 megabits. The remainder is lost due to the signaling protocol used, which ensures that the data to be transmitted reliably, but in Exchange gets your fair share of the baud rate. 🙂

The third layer is the performance hit by WUSB devices under ideal conditions (short distances, unhindered and without interferences), where we have three possibilities.

When connecting two devices with native transmitters, it is possible to achieve real rates of up to 200 megabits. If the distance is greater than one or two meters, the transmission rate drops significantly, but remain at a reasonable value.

To connect a PC with an adapter (WHA) to a device with native support, or a PC with a native transmitter to a device connected to a WDA, the rate drops to the range of 80 to 120 megabits. Finally, when using both a WAH and a WDA (such as Belkin Cable-Free USB) have overhead on both sides and the transmission rate falls further, reaching the age of 30 to 45 megabits.

Contrary to what may seem at first glance, the WUSB is not intended to compete with wireless networks, since it only works at distances too short. You could share the web connection between two notebooks, or between a PC and a PDA using the WUSB, but wouldn’t be the type of solution that you would use in your home network, for example.

The more direct competitor would be Bluetooth, which is also a standard for connecting devices to short distances and fulfills many of the functions that the WUSB intended (it allows you to transfer data between devices and can be used for keyboards and mice, for example). The advantage of the WUSB on the Bluetooth standard is that, in addition to brutally faster, consume less energy transmitters. On this basis, it is possible that the WUSB replace Bluetooth in several applications. The biggest problem is the WUSB is a very new, whose adoption is still undefined.