1 / 5

Smart Antennas Breed Better WLANs

Smart Antennas Breed Better WLANs . Jack H. Winters Chief Scientist Motia, Inc. December 3, 2003 jwinters@motia.com 732 208-5568. Smart Antennas. SIGNAL. SIGNAL. BEAM SELECT. SIGNAL OUTPUT. BEAMFORMER. INTERFERENCE. BEAMFORMER WEIGHTS. INTERFERENCE. Adaptive Antenna Array.

presley
Télécharger la présentation

Smart Antennas Breed Better WLANs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Smart Antennas Breed Better WLANs Jack H. Winters Chief Scientist Motia, Inc. December 3, 2003 jwinters@motia.com 732 208-5568

  2. Smart Antennas SIGNAL SIGNAL BEAM SELECT SIGNAL OUTPUT BEAMFORMER INTERFERENCE BEAMFORMER WEIGHTS INTERFERENCE Adaptive Antenna Array Switched Multibeam Antenna SIGNAL OUTPUT • Smart antenna is a multibeam or adaptive antenna array that tracks the wireless environment to significantly improve the performance of wireless systems • Adaptive arrays in any environment provide: • Antenna gain of M • Suppression of M-1 interferers • In a multipath environment, they also provide: • M-fold multipath diversity gain • With M Tx antennas (MIMO), M-fold data rate increase in same channel with same total transmit power

  3. Smart Antenna AP Smart Antenna Smart Antennas for WLANs AP Smart Antenna Interference Smart Antennas can significantly improve the performance of WLANs • TDD operation (only need smart antenna at access point or terminal for performance improvement in both directions) • Higher antenna gain  Extend range/ Increase data rate/ Extend battery life • Multipath diversity gain  Improve reliability • Interference suppression  Improve system capacity and throughput • Supports aggressive frequency re-use for higher spectrum efficiency, robustness in the ISM band (microwave ovens, outdoor lights) • Data rate increase  M-fold increase in data rate with M Tx and M Rx antennas (MIMO 802.11n)

  4. Smart Antennas for WLANs • Smart Antennas can (and to be successful should): • Be standards compliant • Work with any antennas: • Two antennas on APs and clients today • Four antennas in same space (e.g., PCMCIA card) with dual polarization • Can be added to existing systems for slight cost increase • Can be added to AP or client: • On AP: • All AP users have greater range • Higher system capacity • On client: • Greater range • Interference immunity • On both: • Gains are additive • Evolution to MIMO with standards (802.11n)

  5. JavelinChip Existing Transceiver Adaptive Array Appliqué • Four-antenna RF IC with analog weight calculation (plug-and-play/blind MRC Tx and Rx) provides: • 12-13 dB gain (vs. one antenna) in Rayleigh fading with 802.11b/g • 7-10 dB gain with 30-50 ns delay spread • Increases throughput by 50% (typical) • Reduces power drain by up to 90%

More Related