Friday, May 18, 2012

USB 3.0 Noise and the Wireless Spectrum

Intel has released a White Paper study revealing potential interference issues for wireless receivers caused by noise generated on the USB 3.0 data spectrum.  Signal radiation produced by a USB 3.0 connection can be particularly high in the broadband 2.4-2.5GHz range - a very common frequency for wireless devices of all sorts.  The magnitude of the interference can range from reduction in throughput to total unresponsiveness.

The paper shows the results of a series of experiments which tested the functionality of a simple wireless device in relation to the physical distance from a disconnected, connected, and active USB 3.0 hard drive.  Further studies tested the functionality against a USB 3.0 device with various forms of shielding, both on the receptacle connector and the peripheral device.  Proper shielding was able to successfully reduce signal noise, but since the noise is emitted on a broadband signal within the 2.4-2.5GHz range, it can never be fully filtered out.

Although USB 3.0 is not yet as widely used as other USB technology, Intel's release of the Ivy Bridge chipsets featuring on-board USB 3.0 support is sure to propagate its usage.  Such interference issues are likely to have a wide impact on the end users' application of wireless devices.  Without standardization of shielding or USB 3.0 port placement, design fragmentation is inevitable.  Hardware manufacturers will need thorough testing to ensure sufficient coverage of their wireless device functionality.

The full report for the study can be viewed here.


Post a Comment