US5669060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for enhancing call set-up and handoff quality
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1996-03-04
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Granted: 1997-09-16
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Expires: 2016-03-04
Abstract
Abstract In a cellular telephone system, mobile station measurements of received signal strength on each reference frequency are made in order to select a cell. At call set-up in or handoff to that cell, a voice frequency is selected by the system to carry the communication. A determination is then made as to whether the antenna used for the reference frequency is the same as that used by the selected voice frequency. From this determination, actions are taken as needed to address concerns over potential differences in broadcast coverage areas for the antennas. For example, an alternate voice frequency using the same antenna as the reference frequency may be chosen. Further, a test broadcast may be made on the selected voice frequency for comparison to the received signal strength on the reference frequency in order to confirm the selection of the cell and use of the selected voice frequency.
Inventors
- 👤 Vincent Guimont
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:55
CPC Classifications
H; H04; H04W; H04W76/00; H04W76/10; H04W36/00; H04W36/08
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
103 words
A voice frequency selection method comprising the steps of: selecting one of a plurality of voice frequencies to carry a cellular communication in a cell; determining whether an antenna used by the cell for the selected voice frequency is the same as an antenna used by the cell for a reference frequency; and if not: making a test broadcast on the selected voice frequency; measuring received signal strength for the test broadcast; confirming use of the cell from a sufficient measured test broadcast received signal strength; and responsive to the confirmation of the cell, establishing the cellular communication over the selected voice frequency.
Claim 2
Dependent Claim
103 words
A voice frequency selection method comprising the steps of: selecting one of a plurality of voice frequencies to carry a cellular communication in a cell; determining whether an antenna used by the cell for the selected voice frequency is the same as an antenna used by the cell for a reference frequency; and if not: making a test broadcast on the selected voice frequency; measuring received signal strength for the test broadcast; confirming use of the cell from a sufficient measured test broadcast received signal strength; and responsive to the confirmation of the cell, establishing the cellular communication over the selected voice frequency.
Claim 3
Dependent Claim
31 words
The method as in claim 1 wherein the step of selecting further includes the step of preferring selection of a voice frequency that uses the same antenna as the reference frequency.
Claim 4
Dependent Claim
37 words
The method as in claim 1 further including the step of, responsive to a determination that the same antenna is not being used, selecting an alternative voice frequency that uses the same antenna as the reference frequency.
Claim 5
Dependent Claim
33 words
The method as in claim 1 further including the step of storing a calculated difference between a received signal strength for the reference frequency and the received signal strength for the test broadcast.
Claim 6
Dependent Claim
31 words
The method as in claim 1 further including the step of, responsive to a determination that the same antenna is being used, establishing the cellular communication over the selected voice frequency.
Claim 7
Dependent Claim
20 words
The method as in claim 1 wherein the reference frequency comprises a measurement channel for use in mobile assisted handoff.
Claim 8
Dependent Claim
14 words
The method as in claim 1 wherein the reference frequency comprises a control channel.
Claim 9
Dependent Claim
122 words
In a cellular telephone system wherein a cell base station includes a first antenna and a second antenna, and wherein the first antenna operates over a reference frequency and the second antenna operates over a plurality of voice frequencies, a voice frequency selection method comprising the steps of: selecting one of the plurality of voice frequencies associated with the second antenna to carry a cellular communication; making a test broadcast over the selected voice frequency from the second antenna; measuring received signal strength for the test broadcast; and rejecting the cell base station if the measured test broadcast received signal strength is not substantially equal to a received signal strength measured for a broadcast on the reference frequency from the first antenna.
Claim 10
Dependent Claim
122 words
In a cellular telephone system wherein a cell base station includes a first antenna and a second antenna, and wherein the first antenna operates over a reference frequency and the second antenna operates over a plurality of voice frequencies, a voice frequency selection method comprising the steps of: selecting one of the plurality of voice frequencies associated with the second antenna to carry a cellular communication; making a test broadcast over the selected voice frequency from the second antenna; measuring received signal strength for the test broadcast; and rejecting the cell base station if the measured test broadcast received signal strength is not substantially equal to a received signal strength measured for a broadcast on the reference frequency from the first antenna.
Claim 11
Dependent Claim
42 words
The method as in claim 8 wherein the first antenna operates over another plurality of voice frequencies, and the step of selecting further includes the step of preferring selection of a voice frequency that, like the reference frequency, uses the first antenna.
Claim 12
Dependent Claim
48 words
The method as in claim 8 further including the step of establishing the cellular communication over the selected voice frequency if the measured test broadcast received signal strength is substantially equal to a received signal strength measured for a broadcast on the reference frequency from the first antenna.
Claim 13
Dependent Claim
20 words
The method as in claim 8 wherein the reference frequency comprises a measurement channel for use in mobile assisted handoff.
Claim 14
Dependent Claim
14 words
The method as in claim 8 wherein the reference frequency comprises a control channel.
Claim 15
Dependent Claim
158 words
A mobile switching center for use in a cellular telephone system wherein each cell base station includes a plurality of antennas, and wherein a reference frequency and each of a plurality of voice frequencies used by the cell base stations do not necessarily use the same antenna, and wherein each reference frequency and each of the plurality of voice frequencies has an associated antenna identification number, the mobile switching center operating, responsive to a selection of one of the plurality of voice frequencies for carrying a cellular communication in a cell, to compare the antenna identification number for the selected voice frequency to the antenna identification number for the cell reference frequency and, in the event the antenna identification numbers do not match, the mobile switching center further operating to order the transmission over the selected voice frequency of a test broadcast to confirm sufficient received signal strength to support the cellular communication on the selected voice frequency.
Claim 16
Dependent Claim
158 words
A mobile switching center for use in a cellular telephone system wherein each cell base station includes a plurality of antennas, and wherein a reference frequency and each of a plurality of voice frequencies used by the cell base stations do not necessarily use the same antenna, and wherein each reference frequency and each of the plurality of voice frequencies has an associated antenna identification number, the mobile switching center operating, responsive to a selection of one of the plurality of voice frequencies for carrying a cellular communication in a cell, to compare the antenna identification number for the selected voice frequency to the antenna identification number for the cell reference frequency and, in the event the antenna identification numbers do not match, the mobile switching center further operating to order the transmission over the selected voice frequency of a test broadcast to confirm sufficient received signal strength to support the cellular communication on the selected voice frequency.
Claim 17
Dependent Claim
45 words
The mobile switching center as in claim 13 further operating responsive to insufficient received signal strength for supporting the cellular communication on the selected voice frequency by rejecting the cell in favor of another cell in the cellular telephone system to handle the cellular communication.
Claim 18
Dependent Claim
22 words
The mobile switching center as in claim 13 wherein the reference frequency comprises a measurement channel for use in mobile assisted handoff.
Claim 19
Dependent Claim
16 words
The mobile switching center as in claim 13 wherein the reference frequency comprises a control channel.
Claim 20
Independent Claim
91 words
A method for evaluating the quality of a selected voice frequency in a cellular telephone system in instances where a base station antenna for the selected voice frequency differs from a base station antenna for a reference frequency of a cell, comprising the steps of: making a test broadcast on the selected voice frequency; measuring received signal strength for the test broadcast; and rejecting the selected voice frequency if the measured test broadcast received signal strength is not substantially equal to a received signal strength with respect to the reference frequency.
Claim 21
Independent Claim
91 words
A method for evaluating the quality of a selected voice frequency in a cellular telephone system in instances where a base station antenna for the selected voice frequency differs from a base station antenna for a reference frequency of a cell, comprising the steps of: making a test broadcast on the selected voice frequency; measuring received signal strength for the test broadcast; and rejecting the selected voice frequency if the measured test broadcast received signal strength is not substantially equal to a received signal strength with respect to the reference frequency.
Claim 22
Dependent Claim
43 words
The method as in claim 17 further including the step of rejecting the cell in favor of an alternate cell if the measured test broadcast received signal strength is not substantially equal to a received signal strength with respect to the reference frequency.
Claim 23
Dependent Claim
43 words
The method as in claim 17 further including the steps of: selecting an alternative voice frequency; and repeating the steps of claim 17 if the base station antenna for the alternative voice frequency differs from the base station antenna for the reference frequency.
Claim 24
Dependent Claim
20 words
The method as in claim 17 wherein the reference frequency comprises a measurement channel for use in mobile assisted handoff.
Claim 25
Dependent Claim
14 words
The method as in claim 17 wherein the reference frequency comprises a control channel.
References Cited (Backward Citations)
US4704734A
Cited
US4737978A
Cited
US5097484A
Cited
US4932049A
Cited
US5193109A
Cited
US5175878A
Cited
US5384826A
Cited
US5117236A
Cited
US5138327A
Cited
US5355522A
Cited
US5548809A
Cited
US5481571A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-09-15 | 2001-03-17 | 2001-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-09-15 | 2005-03-17 | 2005-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-09-15 | 2009-03-17 | 2009-09-16 | $7700.00 | Window Closed / Lapsed |