Monday, November 2, 2009

Atheros' XSPAN with 3-Stream MIMO Delivers 450 Mbps

Atheros Communications introduced its AR9300 family of 11n solutions, featuring XSPAN with Signal Sustain Technology-3, or SST3, which provides 450 Mbps PHY rates derived from a 3-stream 11n MIMO configuration. Atheros said this design ensures robust bandwidth and energy efficiencies for latency-free media connectivity for personal computers, digital home networking equipment from retail vendors, carriers and consumer electronics manufacturers, and enterprise/small medium business (SMB) networking equipment.


Atheros' new implementation of 11n leverages a variety of range enhancement options to ensure that the high throughput levels achieved with the 3x3 MIMO configuration are maintained across the entire WLAN link.

  • Low Density Parity Check (LDPC) guards against packet loss at every point on the link.


  • Maximum Likelihood Demodulation (MLD) optimizes MIMO demodulation to boost signal strength at close range.


  • Transmit Beamforming (TxBF) focuses transmit signals to the receiver to enhance the link rate at mid-range on the link continuum.


  • Maximal Ratio Combining (MRC) enables the receiver to optimally combine the MIMO signal paths, aligning time and phase of the signal receive to extend link reliability at longer range.


Atheros calculates that this combination of features results in a median rate-over-range improvement across the entire link of approximately 50 percent versus conventional 2x2 MIMO 11n solutions. Performance is maximized when products on both ends of the link are based on XSPAN with SST3, however the technology provides performance benefits when connected to all 11n solutions, and offers backward compatibility with 11g- and 11a/g-based devices.
http://www.atheros.com