EP0690650A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Traffic driven channel reservation system for handovers in cellular networks
Assignee: AT&T Inc
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Filing: 1995-06-20
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Granted: —
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Expires: 2015-06-20
Abstract
Abstract A method is disclosed for reducing handover failure probability in cellular networks which includes the steps of determining whether a mobile subscriber (72) is traversing a pre-handover zone (62) defined in each cell (52) of the network, reserving a free channel in an adjacent cell (54) for the mobile subscriber traversing the pre-handover zone, and granting the free channel to the mobile subscriber upon entering a handover region (58) extending across the boundary (56) of the adjacent cells (52,54) provided that a free channel is available at such a time, and in the alternative, if a free channel is not available at such a time, the handover request is queued until a free channel becomes available.
Inventors
- 👤 Prathima Agrawal
- 👤 Balakrishnan Narendran
- 👤 Dinesh K. Anvekar
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 03:43
CPC Classifications
H; H04; H04W; H04W72/00; H04W72/50; H04W72/51; H04W28/00; H04W28/16; H04W28/26; H04W36/00; H04W36/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
112 words
A method of allocating channels to mobile subscribers entering a handover region extending between the boundary of first and second adjacent cells of a cellular network, each of said cells having a predetermined number of channels provided therein for call allocation and having a pre-handover zone defined therein proximate the handover region, said method comprising the steps of: a) determining whether a mobile subscriber is traversing the pre-handover zone of said first cell; b) reserving a channel in said second cell for the mobile subscriber traversing the pre-handover zone in said first cell; and c) granting the channel reserved in said second cell to the mobile subscriber upon entering the handover region.
Claim 2
Dependent Claim
37 words
A method according to Claim 1, further comprising the step of queuing the channel request of a mobile subscriber entering the handover region if a channel is not available in said second cell at such a time.
Claim 3
Dependent Claim
48 words
A method according to Claim 2, wherein said step of queuing the channel request of a mobile subscriber comprises ordering the channel requests of each of the mobile subscribers traveling within the handover region in dependence upon the measured power signal associated with each of said mobile subscribers.
Claim 4
Dependent Claim
71 words
A method according to Claim 1, further comprising the step of granting a free channel within said second cell to a new call initiated therein provided that there are no mobile subscribers traveling within the handover region awaiting a free channel in said second cell and the number of free channels in said second cell is greater than the number of mobile subscribers traversing the pre-handover zone in said first cell.
Claim 5
Dependent Claim
26 words
A method according to Claim 4, further comprising the step of blocking said new call if a free channel is not available in said second cell.
Claim 6
Dependent Claim
36 words
A method according to Claim 4, further comprising the step of blocking said new call if there is at least one mobile subscriber traveling within the handover region awaiting a free channel in said second cell.
Claim 7
Dependent Claim
41 words
A method according to Claim 4, further comprising the step of blocking said new call if the number of free channels in said second cell is less than the number of mobile subscribers traversing the pre-handover zone in said first cell.
Claim 8
Dependent Claim
36 words
A method according to Claim 1, wherein said step of determining whether a mobile subscriber is traversing the pre-handover zone comprises calculating a relative position of said mobile subscriber by measuring the power signal transmitted thereby.
Claim 9
Dependent Claim
85 words
A cellular network comprising: a) a plurality of adjoining cells having boundaries extending therebetween and each having a predetermined number of channels provided therein for call allocation; b) a handover region extending across the boundary of adjacent cells wherein on-going calls of mobile subscribers are transferred from one cell to another cell; c) a pre-handover zone defined in each of said plurality of adjoining cells proximate the handover region associated therewith within which channels are reserved in an adjacent cell for mobile subscribers traveling therethrough.
Claim 10
Dependent Claim
50 words
A cellular network as recited in Claim 9, wherein each of said cells has a respective base station located therein which determines whether a mobile subscriber is traversing the pre-handover zone defined therein and communicates a relative position of the mobile subscriber to the base station in an adjacent cell.
Claim 11
Dependent Claim
32 words
A cellular network as recited in Claim 9, wherein the pre-handover zone in each of said cells has a width that is less than the width of the handover region proximate thereto.
Claim 12
Dependent Claim
58 words
In a cellular network having a plurality of cells each defined by a respective boundary, and handover regions extending across the boundaries of adjacent cells, the improvement comprising: a pre-handover zone defined in each of said cells proximate the handover region associated therewith within which free channels are reserved in an adjacent cell for mobile subscribers traveling theretoward.
References Cited (Backward Citations)
US5081671A
Cited
US5189734A
Cited
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