Wireless USB: no more cables between peripheral and pc.

The concept

In order to promote Wireless USB at its official introduction in 2004, Intel introduced the Wireless USB Promoter Group which consisted of the hardware-giants Agere, HP, Intel Microsoft, NEC, Philips and Samsung. To explain how Wireless USB works and which influence it exerts over the use of multimedia, at home and at work, the group issued a brochure out of which we shall highlight some topics.

The Wireless USP Promoter focuses on three main targets: the pc, consumer electronics and mobile communication equipment. In the realm of the living room we then have to think about audio/bideo devices, digital cameras, videocameras, MP3 players, tablet pc’s, wireless speakers and portable monitors. These devices will be connected through pc’s, laptops, HDTV’s, etc. Within the office an integration of monitor, keyboard, mouse, webcam, printer, scanner, external harddisks and USB-sticks (although this name might no longer apply) comes into view. Finally there are some specific products which might benefit from Wireless USB, such as laptops, PDA’s, gsm’s, projectors, headsets and network storage.

Wireless USB is set up in a hub-architecture, just like its cabled sibling (see illustration). The host functions as a distributor and allocates required bandwidth to the clients. The connections are point-to-point, which means that there is no communication between the individual clients. As with conventional USB, the maximum number of connections is 127. The hosting is carried out by a pc, a laptop, an amplifier in a surround-system, a game console, etc. The total configuration of host, clients and the interlinking connections is called a cluster. Clusters can be inter connected through mid-range connections like e.g. WiFi.

There is also a second way of connectingt devices. This so calles dual-role connection is the wireless variety of USB on-the-go. With this flavor of the above mentioned connection-type a device functions both as a host and as a client. We already know this principle from WiFi and Bluetooth. In essence there are several possibilities like e.g. that of a connection from camera to printer. And that particular application can be appreciated quite broadly. Sending pictures to the printer in your home is apparent. But you could also think of sending data to your service provider or to the closest printer in your office. There are plenty examples to think of: from camcorder to monitor, from MP3 player to wireless speakers or headphone, from an external harddisk to HD-DVD or Blue-ray recorder, etc., etc.

Particularly consumer electronics put a high demand on Wireless USB. The criteria regarding performance will consequently be defined in this arena. Because of the use of multiple HDTV-channels, the amount of traffic within a WUSB-hub can increase significantly. However, with a theoretical maximum of 480 MBit/s there should be sufficient bandwidth present. Should at a future point in time this bandwidth be too small there is a backup: the UWB connection supports speeds of above 1 GBit/s. In this respect the USB-specification will be the limiting factor for the time being.

There is no mention of a maximum distance between host and client. It is clear however that wireless USB products can be 10 meters apart. Furthermore, as mentioned earlier, USB and Wireless USB should be mutually compatible. This means that we will see marketing and sales of Wireless USB receivers, dongles and add-in boards, just as we know them in the counterparts Bluetooth and WiFi. To stimulate the acceptance of these devices the prices should be kept attractive. Remember that one of the reasons for USB’s success is its low pricing. Just as the performances are equal, so should the prices be, according to the Wireless USB Promoter Group.