Ultrawideband (UWB) has emerged as the leading technology to address consumer wireless personal area networking (WPAN) applications. LeCroy released the first UWB protocol analyzer for WiMedia based Wireless PANs in April of 2005. LeCroy’s ongoing support for WiMedia testing has made this system a fixture in the verification of WiMedia devices ever since.
Wireless access in devices like cellular handsets and notebooks has helped generate wider interest in wireless capabilities for other consumer devices such as digital cameras, PDA's, portable digital media players and high-definition televisions (HDTVs).
Certified Wireless USB (WUSB) is a high-bandwidth wireless extension to the USB standard that is based on Ultra Wideband at the physical layer. It's designed to combine the speed and security of wired technology with the ease-of-use of wireless communications. WUSB provide 480 Mb/s throughput at distances up to 3 meters (10 feet) making it a compelling choice for adding wireless connectivity to today's digital media devices.
Protocol layer testing for wireless technologies generally involves a radio-based "sniffer" to eavesdrop on the exchange between devices. Analysis tools must perform this task with minimal impact on the real-world operating environment for the devices. LeCroy pioneered the early development of Bluetooth based analysis tools and leveraged this expertise to create a complete Wireless USB/UWB test system.
The developers of Wireless USB have strived to maintain a similar usage model and architecture as wired USB with a host-to-device connection. But unlike its wired predecessor, Wireless USB mandates more stringent attention to security to prevent snooping of wireless data traffic. These requirements are defined in the Certified Wireless USB Association Model Specification v1.0 and govern how devices will discover and establish secure connections. Part of this specification includes mandatory encryption of data packets transmitted over-the-air. This encryption can prevent analysis tools from eavesdropping on secure messages.
LeCroy's UWBTracer™ Protocol Analyzer provides an innovative solution to this security problem. For devices that use the cable association model, LeCroy offers an integrated plug-in for capturing the cable association sequence. Similar to a USB analyzer, this module transparently taps the wired link between host and device. It automatically records and passes the connection context to the radio-based analysis engine contained within the UWBTracer. The analyzer radio channel can then automatically follow the 4-way security handshake and derive the "session" key (or PTK). With this unique session key in the hardware recording engine, the analyzer can automatically decrypt the scrambled wireless traffic. For devices that use the Numeric Association model, LeCroy's UWBTracer provides a software interface for tracking the connection con-text manually between devices.
- In the cable association model, the UWBTracer Analyzer captures the connection context and then transfers this information to the radio module, where it is used to capture and decrypt radio traffic between host and device.
The association models in Certified Wireless USB are designed to deliver secure data transfers and ease-of-use to consumers. Efficient device-level validation requires that the analysis tool have a mechanism to capture and recall the connection context. LeCroy's UWBTracer system significantly improves test workflow by allowing over-the-air protocol monitoring to occur unencumbered by WUSB's security features.
Another key issue for early adopters in Ultra Wideband development is presented by the evolving state of the regulatory environment. Several regions including Europe and Japan have restricted UWB devices by requiring operation in specific channels and/or higher frequencies. Chipsets supporting higher band operation were not widely available in 2008 making investments in test equipment problematic for developers targeting world-wide deployments. Anticipating this issue, LeCroy designed the UWBTracer test system to allow users to quickly change the radio front end on the analyzer. This unique ability to evolve the test equipment to support future changes in the specifications allows test teams to protect their investment in UWB analysis tools and ultimately deliver highest quality products.
UWBTracer/Trainer LeCroy's flagship validation platform for UWB includes an integrated analyzer / exerciser to test functionality, error recovery and compliance for WiMedia and Wireless USB devices
UWBTracer The industry leading protocol analysis system for UWB capable of capturing and decoding wireless USB and WLP