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Combined Power Control and Space-Time Diversity (ISR IP)

ISR intellectual property available to license

Inventors
Farrokh Rashid-Farrokhi, K.J. Ray Liu, Leandros Tassiulas

U.S. Patent 6,377,812

Description
The present invention is a joint power control and space-time diversity scheme for uplinks and downlinks in wireless networks with fading channels. It is ideal for use in base stations for cellular communication systems (both CDMA and TDMA) using smart antennas.

The invention:
1) increases capacity in wireless networks;
2) guarantees signal to noise ratios and quality of service;
3) is amenable to distributed implementation; and
4) saves transmitted power and battery life.

In the uplink, mobile powers and equalization/diversity combining vectors at base stations are calculated jointly. The mobile transmitted power is minimized, while the Signal to Noise Ratio (SNR) at each link is maintained above a threshold. A multitap transmit diversity scheme for the downlink is also proposed where the transmit weight vectors are adjusted such that the SNR at each mobile is set to a specified value. The proposed transmit and receive diversity combining schemes can be applied to networks with fading channels and in cases where the number of cochannels and multipaths are larger than the number of antenna elements. The proposed algorithms achieve the optimal solution for the uplink that minimizes the mobile power, and achieves a feasible solution for the downlink.

For more information
If you would like to license this intellectual property, have questions, would like to contact the inventors, or need more information, contact ISR External Relations Director Jeff Coriale at coriale@umd.edu or 301.405.6604.

Find more ISR IP
You can go to our categorical IP search page to search by research category or faculty name. Or view the entire list of available IP on our main IP search page.

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June 17, 2007


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For more information, contact ISR External Relations Director
Jeff Coriale at coriale@umd.edu or 301.405.6604.

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