US5509027A
Expired / Lapsed
US
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Synchronization method in a frequency hopping local area network having dedicated control channels
Assignee: Google Technology Holdings LLC
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Filing: 1994-12-05
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Granted: 1996-04-16
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Expires: 2014-12-05
Abstract
Abstract A method for a synchronizing user devices (12) performing handoffs includes providing a set of location synchronizing frequencies and data frequencies selected from a hopping set used by network access points (14). Each AP transmits synchronizing data (36) at the synchronizing frequencies during a portion of a short dwell (32), the short dwells (32) being interleaved between long dwells (30). When a user device (12) attempt a handoff, it tunes to at least one of the synchronizing frequencies and receives synchronizing information (36). The user device (12) then selects one AP (14) for link transfer and synchronizes its operation to the hopping set used by the selected AP (14).
Inventors
- 👤 Frederick W. Vook
- 👤 William K. Doss
- 👤 Alan D. Muehlfeld
- 👤 Mai T. Nguyen
- 👤 John E. Shaver
- 👤 Brian J. Wesselman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:51
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/69; H04B1/713; H04B1/7156; H04B7/00; H04B7/24; H04B7/26; H04B7/2621; H04B2001/71563
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
187 words
In a frequency hopping communication system having a plurality of cells, each cell having a hopping sequence comprising an ordered set of data frequencies, and further comprised of a central controller in communication with a plurality of user devices, a method for a user device to acquire synchronization with one of the plurality of cells, comprising the steps of: at the central controllers: providing a set of synchronizing frequencies different from the data frequencies; informing user devices of the synchronizing frequencies; transmitting user data and first synchronization information at a data frequency during respective portions of a long dwell; and transmitting second synchronization information at a synchronizing frequency during a portion of a short dwell, wherein the short dwells are interleaved between the long dwells; at the user device and upon a decision to acquire synchronization: tuning to at least one of the synchronizing frequencies and receiving second synchronization information; processing the received second synchronization information to select a central controller based on the receipt of the second synchronization information; and employing the hopping sequence and interleave pattern used by the selected central controller to commence communication.
Claim 2
Dependent Claim
187 words
In a frequency hopping communication system having a plurality of cells, each cell having a hopping sequence comprising an ordered set of data frequencies, and further comprised of a central controller in communication with a plurality of user devices, a method for a user device to acquire synchronization with one of the plurality of cells, comprising the steps of: at the central controllers: providing a set of synchronizing frequencies different from the data frequencies; informing user devices of the synchronizing frequencies; transmitting user data and first synchronization information at a data frequency during respective portions of a long dwell; and transmitting second synchronization information at a synchronizing frequency during a portion of a short dwell, wherein the short dwells are interleaved between the long dwells; at the user device and upon a decision to acquire synchronization: tuning to at least one of the synchronizing frequencies and receiving second synchronization information; processing the received second synchronization information to select a central controller based on the receipt of the second synchronization information; and employing the hopping sequence and interleave pattern used by the selected central controller to commence communication.
Claim 3
Dependent Claim
25 words
The method according to claim 1 wherein the long dwell correspond to a period of time in the hopping sequence associated with the data frequency.
Claim 4
Dependent Claim
25 words
The method according to claim 1 wherein the short dwell correspond to a period of time in the hopping sequence associated with the synchronization frequency
Claim 5
Dependent Claim
55 words
The method according to claim 1 wherein the length of each long dwell in a first cell are identical and the length of each long dwell in a second cell are identical, while the length of each long dwell in the first cell differ from the length of the long dwells in a second cell.
Claim 6
Dependent Claim
55 words
The method according to claim 1 wherein the length of each short dwell in a first cell are identical and the length of each short dwell in a second cell are identical, while the length of each short dwell in the first cell differ from the length of the short dwells in a second cell.
Claim 7
Dependent Claim
18 words
The method according to claim 1 wherein the length of all long dwells is equal among all cells.
Claim 8
Dependent Claim
18 words
The method according to claim 1 wherein the length of all short dwell is equal among all cells.
Claim 9
Dependent Claim
33 words
The method according to claim 1 wherein the step of receiving second synchronization information further includes the step of receiving information indicating a time duration of the long dwell and the short dwell.
Claim 10
Dependent Claim
34 words
The method according to claim 1 further including the step of providing a first and a second synchronizing frequency said central controller transmitting the second synchronization information on said first and second synchronizing frequencies.
Claim 11
Dependent Claim
16 words
The method according to claim 1 wherein the long dwell is greater than the short dwell.
Claim 12
Dependent Claim
56 words
The method according to claim 1 further comprising the steps of: transmitting first synchronization data during a portion of the long dwell at the same frequency at which the user data is transmitted; and receiving the first synchronization data by the user device such that synchronization between the user device and the central controller is maintained.
Claim 13
Dependent Claim
33 words
The method according to claim 11 wherein the step of receiving first synchronization information further includes the step of receiving information indicating a time duration of the long dwell and the short dwell.
Claim 14
Dependent Claim
33 words
The method according to claim 11 wherein receiving the first synchronizing data further includes the step of receiving information indicating a number of consecutive long dwells and a number of consecutive short dwells.
Claim 15
Dependent Claim
51 words
The method according to claim 1 wherein the step of employing the hopping sequence and interleave pattern further comprises the steps of the user device: determining a number of consecutive long dwells from the second synchronization information; and determining a time duration for the long dwells from the second synchronization information.
Claim 16
Dependent Claim
62 words
The method according to claim 1 wherein the step of employing the hopping sequence and interleave pattern further comprises the steps of the user device: determining a number of consecutive long dwells and a number of consecutive short dwells from the first synchronization information; and determining a time duration for the long dwells and the short dwells from the first synchronization information.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1999-04-16 | 1999-10-16 | 2000-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-04-16 | 2003-10-16 | 2004-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-04-16 | 2007-10-16 | 2008-04-16 | $7700.00 | Window Closed / Lapsed |