US6424834B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Precision hard handoff method using pilot beacon distributors
Assignee: Apple Inc
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Filing: 1999-07-31
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Granted: 2002-07-23
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Expires: 2019-07-31
Abstract
Abstract A method and system for providing a precision hard handoff between two networks is disclosed. The two networks include a first wireless communication system for serving a defined area, such as a campus, at a first frequency and a second wireless communication system adjacent to the first system and operating at a second frequency. A first pilot beacon distributor is positioned at a transition point of the campus for directionally transmitting a first pilot beacon signal into the campus. When a mobile unit operating on the second frequency crosses the transition point into the campus, it receives the first pilot beacon signal and it shifts operation to the first frequency.
Inventors
- 👤 Chu-Rui Chang
- 👤 Meng Yee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:44
CPC Classifications
H; H04; H04W; H04W36/00; H04W36/24; H04W36/32; H04W16/00; H04W16/24; H04W16/30; H04W36/326
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
107 words
A method for a precision hard handoff from a covering network having a first frequency to a target network having a second frequency, said covering network and said target network both using CDMA technology, said method comprising the steps of: installing a plurality of pilot beacon distributors having paired directional antennas; transmitting a pilot beacon signal from one of the pilot beacon distributors; and triggering a precision hard handoff of the mobile unit from the covering network to the target network by using the pilot beacon signal, wherein all the above steps are performed in a small border area between the covering network and the target network.
Claim 2
Independent Claim
107 words
A method for a precision hard handoff from a covering network having a first frequency to a target network having a second frequency, said covering network and said target network both using CDMA technology, said method comprising the steps of: installing a plurality of pilot beacon distributors having paired directional antennas; transmitting a pilot beacon signal from one of the pilot beacon distributors; and triggering a precision hard handoff of the mobile unit from the covering network to the target network by using the pilot beacon signal, wherein all the above steps are performed in a small border area between the covering network and the target network.
Claim 3
Dependent Claim
24 words
The method of claim 1 further comprising connecting a pilot beacon source to the pilot beacon distributors through a plurality of fiber optical cables.
Claim 4
Dependent Claim
37 words
The method of claim 1 wherein the paired directional antennas include a first directional antenna having a high front-to-back signal ratio for transmitting the pilot beacon signal and a second directional antenna for transmitting a non-beacon signal.
Claim 5
Dependent Claim
27 words
The method of claim 3 wherein the second directional antenna is coupled with the first directional antenna in a back lobe direction of the first directional antenna.
Claim 6
Dependent Claim
20 words
The method of claim 3 wherein both the first and the second directional antennas use the first frequency for transmissions.
Claim 7
Dependent Claim
45 words
The method of claim 1 wherein the step of triggering further includes the steps of: receiving the pilot beacon signal by the mobile unit entering the border area; negotiating a handoff with the covering network; and completing the precision hard handoff to the target network.
Claim 8
Dependent Claim
64 words
The method of claim 6 wherein, when the mobile unit is active, the step of negotiating further includes the steps of: requesting a soft handoff to the covering network by the mobile unit; identifying the pilot beacon by the covering network; refusing the soft handoff by the covering network; and instructing the mobile unit to start the precision hard handoff to the target network.
Claim 9
Dependent Claim
67 words
The method of claim 6 wherein, when the mobile unit is idle, the step of negotiating further includes the steps of: identifying the pilot beacon signal by the mobile unit; reading the information in a paging channel by the mobile unit; and instructing the mobile unit to start the precision hard handoff to the target network by a pre-enabled Global Service Redirection parameter in the paging channel.
Claim 10
Independent Claim
236 words
A method for a precision hard handoff of a mobile unit between a first CDMA communication network using a first frequency and a second CDMA communication network using a second frequency, the mobile unit using the first frequency if it is covered initially under the first network and using the second frequency if it is covered initially under the second network, the method comprising the steps of: installing a first pilot beacon distributor for directing the precision hard handoff from the first network to the second network in a border area between the first and the second networks; installing a second pilot beacon distributor for directing the hard handoff from the second network to the first network in the border area between the first and the second networks; transmitting a first pilot beacon signal by the first pilot beacon distributor at the first frequency; transmitting a second pilot beacon signal by the second pilot beacon distributor at the second frequency; identifying the first pilot beacon signal by the mobile unit if the mobile unit moves from the first network to the second network; identifying the second pilot beacon signal by the mobile unit if the mobile unit moves from the second network to the first network; negotiating a needed handoff; and completing the precision hard handoff, wherein all the above steps are taken in a small border area between the first network and the second network.
Claim 11
Independent Claim
236 words
A method for a precision hard handoff of a mobile unit between a first CDMA communication network using a first frequency and a second CDMA communication network using a second frequency, the mobile unit using the first frequency if it is covered initially under the first network and using the second frequency if it is covered initially under the second network, the method comprising the steps of: installing a first pilot beacon distributor for directing the precision hard handoff from the first network to the second network in a border area between the first and the second networks; installing a second pilot beacon distributor for directing the hard handoff from the second network to the first network in the border area between the first and the second networks; transmitting a first pilot beacon signal by the first pilot beacon distributor at the first frequency; transmitting a second pilot beacon signal by the second pilot beacon distributor at the second frequency; identifying the first pilot beacon signal by the mobile unit if the mobile unit moves from the first network to the second network; identifying the second pilot beacon signal by the mobile unit if the mobile unit moves from the second network to the first network; negotiating a needed handoff; and completing the precision hard handoff, wherein all the above steps are taken in a small border area between the first network and the second network.
Claim 12
Dependent Claim
50 words
The method of claim 9 wherein the step of installing a first pilot beacon distributor further includes the steps of: installing a pilot beacon source for generating the first pilot beacon signal; and transmitting the first pilot beacon signal to the first pilot beacon distributor through a fiber optical cable.
Claim 13
Dependent Claim
50 words
The method of claim 9 wherein the step of installing a second pilot beacon distributor further includes the steps of: installing a pilot beacon source for generating the second pilot beacon signal; and transmitting the second pilot beacon signal to the second pilot beacon distributor through a fiber optical cable.
Claim 14
Dependent Claim
50 words
The method of claim 9 wherein the first pilot beacon distributor includes a first directional antenna transmitting the first pilot beacon signals at the first frequency and a second directional antenna coupled in a back lobe direction of the first directional antenna transmitting other signals also at the first frequency.
Claim 15
Dependent Claim
16 words
The method of claim 12 wherein the first directional antenna has a high front-to-back signal ratio.
Claim 16
Dependent Claim
49 words
The method of claim 9 wherein the second pilot beacon distributor includes a first directional antenna transmitting the second pilot beacon signals at the second frequency and a second directional antenna coupled in a back lobe direction of the first directional antenna transmitting non-beacon signals at the second frequency.
Claim 17
Dependent Claim
16 words
The method of claim 14 wherein the first directional antenna has a high front-to-back signal ratio.
Claim 18
Dependent Claim
75 words
The method of claim 9 wherein, when the mobile unit is active and moving from the first network to the second network, the step of negotiating further includes the steps of: requesting a soft handoff to the first network by the mobile unit; identifying the first pilot beacon by the first network; refusing the soft handoff by the first network; and instructing the mobile unit to start the precision hard handoff to the second network.
Claim 19
Dependent Claim
25 words
The method of claim 16 wherein the step of requesting includes sending a Pilot Strength Measurement Message to the first network by the mobile unit.
Claim 20
Dependent Claim
25 words
The method of claim 16 wherein the step of instructing includes sending an Extended Handoff Direction Message to the mobile unit by the first network.
Claim 21
Dependent Claim
75 words
The method of claim 9 wherein, when the mobile unit is active and moving from the second network to the first network, the step of negotiating further includes the steps of: requesting a soft handoff to the second network by the mobile unit; identifying the second pilot beacon by the first network; refusing the soft handoff by the second network; and instructing the mobile unit to start the precision hard handoff to the first network.
Claim 22
Dependent Claim
25 words
The method of claim 19 wherein the step of requesting includes sending a Pilot Strength Measurement Message to the second network by the mobile unit.
Claim 23
Dependent Claim
25 words
The method of claim 19 wherein the step of instructing includes sending an Extended Handoff Direction Message to the mobile unit by the second network.
Claim 24
Dependent Claim
75 words
The method of claim 9 wherein, when the mobile unit is idle, the step of negotiating further includes the steps of: identifying the first or the second pilot beacon signal by the mobile unit; reading the information in a paging channel by the mobile unit; and instructing the mobile unit to start the precision hard handoff to the first or the second network determined by a pre-enabled Global Service Redirection parameter in the paging channel.
Claim 25
Independent Claim
98 words
A system for directing a mobile unit to complete a precision hard handoff from a covering network having a first frequency to a target network having a second frequency, said covering network and said target network both use CDMA technology, said system comprising: a plurality of pilot beacon distributors having paired directional antennas in a border area between the covering network and the target network for transmitting pilot beacon signals; and means for triggering a precision hard handoff of the mobile unit from the covering network to the target network by using one of the pilot beacon signals.
Claim 26
Independent Claim
98 words
A system for directing a mobile unit to complete a precision hard handoff from a covering network having a first frequency to a target network having a second frequency, said covering network and said target network both use CDMA technology, said system comprising: a plurality of pilot beacon distributors having paired directional antennas in a border area between the covering network and the target network for transmitting pilot beacon signals; and means for triggering a precision hard handoff of the mobile unit from the covering network to the target network by using one of the pilot beacon signals.
Claim 27
Dependent Claim
24 words
The system of claim 23 wherein the pilot beacon distributors are connected to a pilot beacon source through a plurality of fiber optical cables.
Claim 28
Dependent Claim
36 words
The system of claim 23 wherein the paired directional antennas include a first directional antenna having a high front-to-back signal ratio for transmitting the pilot beacon signal and a second directional antenna for transmitting non-beacon signals.
Claim 29
Dependent Claim
27 words
The system of claim 25 wherein the second directional antenna is coupled with the first directional antenna in a back lobe direction of the first directional antenna.
Claim 30
Dependent Claim
20 words
The system of claim 25 wherein both the first and the second directional antennas use the first frequency for transmissions.
Claim 31
Dependent Claim
35 words
The system of claim 23 whereby the mobile unit receives the pilot beacon signal in the border area, negotiates a handoff with the covering network, and completes the precision hard handoff to the target network.
Claim 32
Dependent Claim
61 words
The system of claim 28 whereby the mobile unit negotiates the handoff, when the mobile unit is active, comprising: means for identifying the pilot beacon in response to a soft handoff request sent to the covering network; means for refusing the soft handoff request; and means for instructing the mobile unit to start the precision hard handoff to the target network.
Claim 33
Dependent Claim
52 words
The system of claim 28 whereby the mobile unit negotiates the handoff, when the mobile unit is idle, comprising: means for instructing the mobile unit to start the precision hard handoff to the target network by a pre-enabled Global Service Redirection parameter in a paging channel indicated by the pilot beacon signal.
Claim 34
Dependent Claim
110 words
A wireless communication system for providing high volume coverage inside a primary coverage area operating at a primary frequency, the system comprising: at least one base station in the high volume coverage area operating at a second frequency; and a first pilot beacon distributor positioned at a transition point between the primary coverage area and the high volume coverage area for directionally transmitting a first pilot beacon signal into the high volume coverage area; whereby a mobile unit operating on the primary frequency and traveling into the high volume coverage area can receive the first pilot beacon signal and shift operation to the second frequency when crossing the transition point.
Claim 35
Dependent Claim
110 words
A wireless communication system for providing high volume coverage inside a primary coverage area operating at a primary frequency, the system comprising: at least one base station in the high volume coverage area operating at a second frequency; and a first pilot beacon distributor positioned at a transition point between the primary coverage area and the high volume coverage area for directionally transmitting a first pilot beacon signal into the high volume coverage area; whereby a mobile unit operating on the primary frequency and traveling into the high volume coverage area can receive the first pilot beacon signal and shift operation to the second frequency when crossing the transition point.
Claim 36
Dependent Claim
68 words
The system of claim 31 further comprising: a second pilot beacon distributor positioned at the transition point for directionally transmitting a second pilot beacon signal away from the high volume coverage area; whereby a mobile unit operating on the second frequency and traveling out of the high volume coverage area can receive the second beacon signal and shift operation to the primary frequency when crossing the transition point.
Claim 37
Dependent Claim
15 words
The system of claim 31 wherein the first beacon signal operates at the primary frequency.
Claim 38
Dependent Claim
15 words
The system of claim 31 wherein the second beacon signal operates at the second frequency.
Claim 39
Dependent Claim
29 words
The system of claim 32 wherein the first and second beacon signal distributors are positioned at a distance to prevent a ping-pong phenomenon between the primary and second frequencies.
Claim 40
Dependent Claim
73 words
The system of claim 32 wherein the first beacon signal distributor has a first directional antenna having a high front-to-back signal ratio for transmitting the first pilot beacon signal and enhancing the coverage of the second frequency, and a second directional antenna coupled in a back lobe direction of the first directional antenna for improving the precision of the hard handoff, eliminating a ping-pong phenomenon, and enhancing the coverage of the primary frequency.
Claim 41
Dependent Claim
73 words
The system of claim 32 wherein the second beacon signal distributor has a first directional antenna having a high front-to-back signal ratio for transmitting the second pilot beacon signal and enhancing the coverage of the second frequency, and a second directional antenna coupled in a back lobe direction of the first directional antenna for improving the precision of the hard handoff, eliminating a ping-pong phenomenon, and enhancing the coverage of the primary frequency.
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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) | 2005-07-22 | 2006-01-21 | 2006-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-07-22 | 2010-01-21 | 2010-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-07-22 | 2014-01-21 | 2014-07-23 | $7700.00 | Window Closed / Lapsed |