Patent US5276906A successfully refreshed from Google Patents.
US5276906A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiotelephone system incorporating two thresholds for handoff
Assignee: Motorola Solutions Inc
•
Filing: 1993-04-13
•
Granted: 1994-01-04
•
Expires: 2013-04-13
Abstract
Abstract A digital radiotelephone system requiring a transfer of communication from a source base-site (200) in a source cell (100) to a selected one target base-site in a target cell. A source base-site (200) in the source cell (100) provides a first and a second threshold and measures the received signal strength of a mobile unit (225) communicating to the source base-site (200). When the measured signal strength at the source base-site (200) falls below the first threshold, the source base-site (200) initiates a handoff to target base-sites located by the mobile unit (225). The target base-sites measure the received signal strength of the mobile unit (225) and a target base-site is selected. The source base-site (200) is notified of the selected target base-site and hands off communication of the mobile unit (225) to the selected target base-site when the previously measured signal strength at the source base-site (200) falls below the second threshold.
Inventors
- 👤 Kenneth A. Felix
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:12
CPC Classifications
H; H04; H04W; H04W36/00; H04W36/24; H04W36/30; H04W36/302; H04W36/08
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
164 words
A radiotelephone system requiring a communication transfer from a source base-site to a selected one target base-site, comprising: means for providing a first threshold and a second threshold each associated with the source base-site; means for obtaining a first signal quality value of a signal received by the source base-site; means for obtaining a second signal quality value of said signal received by at least the selected one target base-site; means for sending a communication transfer request to at least the selected one target base-site when said first signal quality value is less than said first threshold; means, at the selected target base-site and coupled to said means for sending, for responding to the source base-site when said second signal quality value is greater than said first signal quality value; and means, coupled to said means for responding, for transferring communication from the source base-site to the selected one target base-site when said first signal level quality value is less than said second threshold.
Claim 2
Dependent Claim
164 words
A radiotelephone system requiring a communication transfer from a source base-site to a selected one target base-site, comprising: means for providing a first threshold and a second threshold each associated with the source base-site; means for obtaining a first signal quality value of a signal received by the source base-site; means for obtaining a second signal quality value of said signal received by at least the selected one target base-site; means for sending a communication transfer request to at least the selected one target base-site when said first signal quality value is less than said first threshold; means, at the selected target base-site and coupled to said means for sending, for responding to the source base-site when said second signal quality value is greater than said first signal quality value; and means, coupled to said means for responding, for transferring communication from the source base-site to the selected one target base-site when said first signal level quality value is less than said second threshold.
Claim 3
Dependent Claim
30 words
The radiotelephone system of claim 1 wherein said means for sending said communication transfer request further comprises means for including said first signal quality value in said communication transfer request.
Claim 4
Dependent Claim
72 words
The radiotelephone system of claim 1 wherein said means for transferring communication from the source base-site to the selected one target base-site when said first signal level quality value is less than said second threshold further comprises means for transferring communication from the source base-site to the selected one target base-site when said second signal quality value is greater than said first signal quality value and when said means for responding responds.
Claim 5
Dependent Claim
40 words
The radiotelephone system of claim 1 wherein said means for obtaining a first signal quality value further comprises means for providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site.
Claim 6
Dependent Claim
56 words
The radiotelephone system of claim 4 wherein said means for responding to the source base-site when said second signal quality value is greater than said first signal quality value further comprises means for responding to the source base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value.
Claim 7
Dependent Claim
265 words
A radiotelephone system having a mobile unit communicating to a source base-site, the mobile unit requiring a transfer of communication from the source base-site to a selected one target base-site, the radiotelephone system comprising: means for providing a first threshold and a second threshold each associated with the source base-site; means, at the source base-site, for obtaining a first signal quality value of the mobile unit communicating with the source base-site; means, at the source base-site, for receiving information from the mobile unit; means, at at least the selected one target base-site, for obtaining a second signal quality value of the mobile unit communicating with the source base-site; means, coupled to said means for obtaining a first signal quality value, for providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site; means for comparing said first signal quality value to said first threshold and for comparing said first signal quality value to said second threshold; means, coupled to said means for receiving, for sending said first signal quality value to at least the selected one target base-site when said first signal quality value is less than said first threshold; means, at at least the selected one target base-site, for responding to the source base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value; and means, coupled to said means for responding, for transferring communication from the source base-site to the selected one target base-site when said first signal quality value is less than said second threshold.
Claim 8
Dependent Claim
265 words
A radiotelephone system having a mobile unit communicating to a source base-site, the mobile unit requiring a transfer of communication from the source base-site to a selected one target base-site, the radiotelephone system comprising: means for providing a first threshold and a second threshold each associated with the source base-site; means, at the source base-site, for obtaining a first signal quality value of the mobile unit communicating with the source base-site; means, at the source base-site, for receiving information from the mobile unit; means, at at least the selected one target base-site, for obtaining a second signal quality value of the mobile unit communicating with the source base-site; means, coupled to said means for obtaining a first signal quality value, for providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site; means for comparing said first signal quality value to said first threshold and for comparing said first signal quality value to said second threshold; means, coupled to said means for receiving, for sending said first signal quality value to at least the selected one target base-site when said first signal quality value is less than said first threshold; means, at at least the selected one target base-site, for responding to the source base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value; and means, coupled to said means for responding, for transferring communication from the source base-site to the selected one target base-site when said first signal quality value is less than said second threshold.
Claim 9
Dependent Claim
32 words
The radiotelephone system of claim 6 wherein said means for receiving information from the mobile unit further comprises means for receiving an identification of at least one target base-site for communication transfer.
Claim 10
Independent Claim
131 words
A method of communication transfer from a source base-site to a selected one target base-site in a radiotelephone system comprising the steps of: providing a first threshold and a second threshold each associated with the source base-site; obtaining a first signal quality value of a signal received by the source base-site; obtaining a second signal quality value of said signal received by at least the selected one target base-site; sending a communication transfer request when said first signal quality value is less than said first threshold; responding to the source base-site when said second signal quality value is greater than said first signal quality value; and transferring communication from the source base-site to the selected one target base-site when said first signal level quality value is less than said second threshold.
Claim 11
Independent Claim
131 words
A method of communication transfer from a source base-site to a selected one target base-site in a radiotelephone system comprising the steps of: providing a first threshold and a second threshold each associated with the source base-site; obtaining a first signal quality value of a signal received by the source base-site; obtaining a second signal quality value of said signal received by at least the selected one target base-site; sending a communication transfer request when said first signal quality value is less than said first threshold; responding to the source base-site when said second signal quality value is greater than said first signal quality value; and transferring communication from the source base-site to the selected one target base-site when said first signal level quality value is less than said second threshold.
Claim 12
Dependent Claim
30 words
The method of claim 8 wherein said step of sending said communication transfer request further comprises the step of including said first signal quality value in said communication transfer request.
Claim 13
Dependent Claim
60 words
The method of claim 8 wherein said step of transferring communication from the source base-site to the selected one target base-site when said second signal quality value is greater than said first signal quality value further comprises the step of maintaining communication on the source base-site when said second signal quality value is less than said first signal quality value.
Claim 14
Dependent Claim
40 words
The method of claim 8 wherein said step of obtaining a first signal quality value further comprises the step of providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site.
Claim 15
Dependent Claim
70 words
The method of claim 11 wherein said step of transferring communication from the source base-site to the selected one target base-site when said second signal quality value is greater than said first signal quality value further comprises the step of transferring communication from the source base-site to the selected one target base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value.
Claim 16
Independent Claim
222 words
A method of communication transfer in radiotelephone system having a mobile unit communicating to a source base-site, the mobile unit requiring a transfer of communication from the source base-site to a selected one target base-site, the method comprising the steps of: providing a first threshold and a second threshold each associated with the source base-site; obtaining, at the source base-site, a first signal quality value of the mobile unit communicating with the source base-site; receiving, at the source base-site, information from the mobile unit; obtaining, at at least the selected one target base-site, a second signal quality value of the mobile unit communicating with the source base-site; providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site; comparing said first signal quality value to said first threshold and comparing said first signal quality value to said second threshold; sending said first signal quality value to at least the selected one target base-site when said first signal quality value is less than said first threshold; responding to the source base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value; and transferring communication from the source base-site to the selected one target base-site when said first signal quality value is less than said second threshold.
Claim 17
Independent Claim
222 words
A method of communication transfer in radiotelephone system having a mobile unit communicating to a source base-site, the mobile unit requiring a transfer of communication from the source base-site to a selected one target base-site, the method comprising the steps of: providing a first threshold and a second threshold each associated with the source base-site; obtaining, at the source base-site, a first signal quality value of the mobile unit communicating with the source base-site; receiving, at the source base-site, information from the mobile unit; obtaining, at at least the selected one target base-site, a second signal quality value of the mobile unit communicating with the source base-site; providing a hysteresis value correlating the physical locations of the source base-site and at least the selected one target base-site; comparing said first signal quality value to said first threshold and comparing said first signal quality value to said second threshold; sending said first signal quality value to at least the selected one target base-site when said first signal quality value is less than said first threshold; responding to the source base-site when said second signal quality value is greater than said first signal quality value plus said hysteresis value; and transferring communication from the source base-site to the selected one target base-site when said first signal quality value is less than said second threshold.
Claim 18
Dependent Claim
32 words
The method of claim 13 wherein said step of receiving information from the mobile unit further comprises the step of receiving an identification of at least one target base-site for communication transfer.
References Cited (Backward Citations)
US3328698A
Cited
US3913017A
Cited
US3898390A
Cited
US3906166A
Cited
US4485486A
Cited
US4475010A
Cited
US4556760A
Cited
JPS6292528A
Cited
US4704734A
Cited
JPS62210792A
Cited
US4670906A
Cited
US4696027A
Cited
US4718081A
Cited
US4794635A
Cited
US4775995A
Cited
US5067171A
Cited
US4811380A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-01-03 | 1997-07-05 | 1998-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-03 | 2001-07-05 | 2002-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-03 | 2005-07-05 | 2006-01-04 | $7700.00 | Window Closed / Lapsed |