US Patent No: 4,718,081

Number of patents in Portfolio can not be more than 2000

Method and apparatus for reducing handoff errors in a cellular radio telephone communications system

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Abstract

Wrong handoffs in a cellular radio telephone RF communications system can be minimized or eliminated without increasing locating receiver equipment requirements, field strength measurement time or system response time. Field strength measurements are made at handoff candidate cells and also at cells neighboring (geographically proximate to) those candidate cells. A weighted average of the measured field strength of the candidate cell and the field strength measured in cells neighboring the candidate cell is calculated for each candidate cell (the field strengths measured by neighboring cells may be multiplied by a weighting factor of 0.5). The weighted averages for the candidate cells are compared, and the candidate cell corresponding to the highest average is selected to handle the mobile transceiver call. Statistical analysis shows that this technique for determining handoff candidates significantly reduces the probability that a call will be handed off to a cell which is geographically distant from the mobile transceiver--even in the presence of propagation anomalies.

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First Claim

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Patent Owner(s)

Patent OwnerAddressTotal Patents
ERICSSON GE MOBILE COMMUNICATIONS INC.LYNCHBURG, VA374
GENERAL ELECTRIC COMPANYSCHENECTADY, NY28549

International Classification(s)

  • International Classification not provided for expired patents

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Brenig, Theodore Lynchburg, VA 3 174

Cited Art

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Patent Citation Ranking

  • Citation Ranking not provided for expired patents

Forward Cites

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