US5367559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sequential power estimation for cellular system handoff
Assignee: Raytheon Co
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Filing: 1992-05-11
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Granted: 1994-11-22
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Expires: 2012-05-11
Abstract
Abstract Cellular handoff is improved by tailing or adapting the measurement time based on the characteristics of the received signal intensity or power. More particularly, base stations typically measure mobile signal power in order to determine the necessity for handoff and the identity of a new cell. The measurement time must be of a duration which is sufficient to characterize the environment of the mobile. In accordance with the invention, the duration of the measurement time is determined from the received signal itself. Once the duration of the measurement time is determined, that data may be passed to a target cell along with other handoff data.
Inventors
- 👤 Stanley Kay
- 👤 Youngky Kim
- 👤 Lou King
- 👤 Ashok D. Mehta
- 👤 Charles Barnett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:30
CPC Classifications
H; H04; H04W; H04W36/00; H04W36/24; H04W36/30; H04W36/302
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
88 words
In a method of handing off a mobile station from a serving cell to a target cell in a cellular telephone system, based on a determination of signal intensity from said mobile station, a method for measuring said signal intensity comprising the steps of: a) sampling a received signal intensity from the mobile station for a predetermined duration, and b) determining from samples collected in step a) whether further sampling is or is not required to determine said received signal intensity to within a predetermined degree of accuracy.
Claim 2
Dependent Claim
88 words
In a method of handing off a mobile station from a serving cell to a target cell in a cellular telephone system, based on a determination of signal intensity from said mobile station, a method for measuring said signal intensity comprising the steps of: a) sampling a received signal intensity from the mobile station for a predetermined duration, and b) determining from samples collected in step a) whether further sampling is or is not required to determine said received signal intensity to within a predetermined degree of accuracy.
Claim 3
Dependent Claim
25 words
A method as recited in claim 1 further comprising the step of transmitting an indication of the determination of step b) to a target cell.
Claim 4
Dependent Claim
67 words
A method as recited in claim 1 wherein said sampling step includes: (a1) calculating from the samples collected in step (a) a calculated fade rate R, and wherein said determining step (b) includes: (b1) comparing the calculated fade rate R to a threshold fade rate R1, and (b2) concluding that further sampling is not required if said calculated fade rate R exceeds said threshold fade rate R.
Claim 5
Dependent Claim
35 words
A method as recited in claim 3 wherein said determining step (b) further includes: (b3) concluding that further sampling is required if said calculated fade rate R does not exceed said threshold fade rate R.
Claim 6
Dependent Claim
70 words
A method as recited in claim 1 comprising the further steps, in the event that further sampling is determined to be required, of: c) sampling the received signal intensity from the mobile for a second predetermined duration, and d) determining from the samples collected in steps a) and c) if further sampling is or is not required to determine said received signal intensity to within said predetermined degree of accuracy.
Claim 7
Dependent Claim
17 words
A method as recited in claim 5 wherein the sampling is carried out at the serving cell.
Claim 8
Dependent Claim
17 words
A method as recited in claim 5 wherein the measurement is carried out at the target cell.
Claim 9
Dependent Claim
46 words
A method as recited in claim 7 comprising the further step of receiving, at a target cell, an indication from the serving cell of the required sampling duration required to determine the received signal intensity from the mobile station to within said predetermined degree of accuracy.
Claim 10
Dependent Claim
41 words
A method as recited in claim 5 further comprising the step of repeating steps c) and d) until either said received signal intensity has been determined to within said predetermined degree of accuracy or until a maximum sampling time has elapsed.
Claim 11
Dependent Claim
29 words
A method as recited in claim 9 further comprising the step of transmitting an indication of the number of repetitions of steps c) and d) to the target cell.
Claim 12
Dependent Claim
99 words
In a system for handing off a mobile station from one cell to another in a cellular telephone system based on a received signal intensity, an apparatus for measuring a received signal intensity comprising: a) means for sampling a received signal intensity from the mobile station, b) a controller including first means to control said sampling means to sample said received signal for a predetermined duration, and c) means for determining, from samples collected by the means for sampling, whether further sampling is or is not required to determine said signal intensity to within a predetermined degree of accuracy.
Claim 13
Dependent Claim
99 words
In a system for handing off a mobile station from one cell to another in a cellular telephone system based on a received signal intensity, an apparatus for measuring a received signal intensity comprising: a) means for sampling a received signal intensity from the mobile station, b) a controller including first means to control said sampling means to sample said received signal for a predetermined duration, and c) means for determining, from samples collected by the means for sampling, whether further sampling is or is not required to determine said signal intensity to within a predetermined degree of accuracy.
Claim 14
Dependent Claim
27 words
Apparatus as recited in claim 11 and further comprising means responsive to the means for determining for transmitting an indication of the determination to a target cell.
Claim 15
Dependent Claim
32 words
Apparatus as recited in claim 11 further comprising second means in said controller to control said sampling means to sample the received signal from the mobile station for a second predetermined duration.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-11-21 | 1998-05-23 | 1998-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-21 | 2002-05-23 | 2002-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-21 | 2006-05-23 | 2006-11-22 | $7700.00 | Window Closed / Lapsed |