US5594720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple access cellular communication with dynamic slot allocation and reduced co-channel interferences
Assignee: Nokia of America Corp
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Filing: 1994-12-27
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Granted: 1997-01-14
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Expires: 2014-12-27
Abstract
Abstract An apparatus and method for reducing co-channel interference in multiple-access cellular communication systems in which frame time or frequency slots are allocated between uplink and downlink. An omnidirectional antenna or a set of directional antennas are used in each cell base station to communicate with users. The frame slots in which the antennas communicate uplink and downlink information are arranged in accordance with a predetermined frame organization to reduce mixed co-channel interference (CCI). Mixed CCI occurs when a downlink transmission from one base station antenna in a given cell interferes with uplink reception in another base station antenna in a frequency reuse (FR) cell. A potentially-interfering antenna in a given cell is therefore directed to transmit downlink information in a different portion of the frame than that in which a potentially-interfered-with antenna in the frequency reuse cell receives uplink information. The frame slots may be allocated such that only a portion of the available slots are dynamically allocated in accordance with user demand, while the remaining portions are assigned to either uplink or downlink communication.
Inventors
- 👤 Haralabos C. Papadopoulos
- 👤 Carl-Erik W. Sundberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:37
CPC Classifications
H; H04; H04W; H04W72/00; H04W72/50; H04W72/54; H04W72/541; H04B; H04B7/00; H04B7/24; H04B7/26; H04B7/2643; H04B7/2656; H04J; H04J3/00; H04J3/16; H04J3/1694; H04W16/00; H04W16/02; H04W16/12; H04W16/24; H04W72/04; H04W72/044; H04W72/0446; H04W74/00; H04W74/04
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
150 words
A communication system for communicating information in slots of a frame, the system comprising: a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially-interfering antenna; a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
Claim 2
Dependent Claim
150 words
A communication system for communicating information in slots of a frame, the system comprising: a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially-interfering antenna; a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
Claim 3
Dependent Claim
21 words
The system of claim 1 wherein at least one of the potentially-interfering antenna and the potentially-interfered-with antenna is an omnidirectional antenna.
Claim 4
Dependent Claim
41 words
The system of claim 1 wherein the first base station has a first set of directional antennas which includes the potentially-interfering antenna, and further wherein the second base station has a second set of directional antennas which includes the potentially-interfered-with antenna.
Claim 5
Dependent Claim
38 words
The system of claim 3 wherein the allocating means allocate the slots such that the directional antennas in each base station receive uplink information in one order and transmit downlink information in an opposite order within the frame.
Claim 6
Dependent Claim
36 words
The system of claim 3 wherein both the first and second sets of directional antennas include three directional antennas A, B and C with each antenna providing about 120° of coverage around the corresponding base station.
Claim 7
Dependent Claim
46 words
The system of claim 5 wherein the allocating means allocate the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, C] or [C, B, A].
Claim 8
Dependent Claim
37 words
The system of claim 3 wherein both the first and second sets of directional antennas include four directional antennas A, B, A' and B' with each antenna providing about 90° of coverage around the corresponding base station.
Claim 9
Dependent Claim
48 words
The system of claim 7 wherein the allocating means allocate the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, B', A'] or [A', B', B, A].
Claim 10
Dependent Claim
37 words
The system of claim 3 wherein the first and second sets of directional antennas include six directional antennas A, B, C, A', B' and C' with each providing about 60° of coverage around the corresponding base station.
Claim 11
Dependent Claim
52 words
The system of claim 9 wherein the allocating means allocate the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, C, C', B', A' ]or [A', B', C', C, B, A].
Claim 12
Dependent Claim
52 words
The system of claim 3 wherein the means for allocating the slots further includes a processor which uses status information in a control slot of the frame to identify which of the directional antennas is being used by a given user, and which assigns slots based on a predetermined slot-direction frame organization.
Claim 13
Independent Claim
155 words
A method of communicating information in allocated slots of a frame in a communication system, wherein the system includes a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the method comprising the steps of: providing a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, wherein the first base station includes a potentially-interfering antenna which can interfere with reception of uplink information in a potentially-interfered-with antenna in the second base station; and allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
Claim 14
Independent Claim
155 words
A method of communicating information in allocated slots of a frame in a communication system, wherein the system includes a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the method comprising the steps of: providing a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, wherein the first base station includes a potentially-interfering antenna which can interfere with reception of uplink information in a potentially-interfered-with antenna in the second base station; and allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
Claim 15
Dependent Claim
69 words
The method of claim 12 wherein the step of allocating the slots further includes: assigning a first portion of the slots in the frame to uplink communication; assigning a second portion of the slots in the frame to downlink communication; and dynamically allocating a third portion of the slots in the frame to either uplink or downlink communication depending on demand from the users in each of the cells.
Claim 16
Dependent Claim
51 words
The method of claim 12 wherein the first base station has a first set of directional antennas which includes the potentially-interfering antenna and further wherein the step of providing the second base station includes providing the second base station with a second set of directional antennas which includes the potentially-interfered-with antenna.
Claim 17
Dependent Claim
43 words
The method of claim 14 wherein the step of allocating the slots further includes allocating the slots such that the directional antennas in each base station receive uplink information in one order and transmit downlink information in an opposite order within the frame.
Claim 18
Dependent Claim
81 words
The method of claim 14 wherein both the first and second sets of directional antennas include three directional antennas A, B and C with each antenna providing about 120° of coverage around the corresponding base station, and the step of allocating the slots includes allocating the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, C] or [C, B, A].
Claim 19
Dependent Claim
84 words
The method of claim 14 wherein both the first and second sets of directional antennas include four directional antennas A, B, A' and B' with each antenna providing about 90° of coverage around the corresponding base station, and the step of allocating the slots includes allocating the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, B', A'] or [A', B', B, A].
Claim 20
Dependent Claim
85 words
The method of claim 14 wherein both the first and second sets of directional antennas include six directional antennas A, B, C, A', B' and C' with each providing about 60° of coverage around the corresponding base station, and the step of allocating the slots includes allocating the slots such that the directional antennas receive uplink information in a given order and transmit downlink information in an opposite order and further wherein the given order is [A, B, C, C', B', A'] or [A', B',C',C,B,A].
Claim 21
Dependent Claim
90 words
In a communication system adapted to communicate information in allocated frame slots on an uplink and downlink between a user and a base station in a cell, a method of allocating slots comprising the steps of: assigning a first portion of a plurality of slots in a frame for communication on the uplink; assigning a second portion of the plurality of slots for communication on the downlink; and dynamically allocating slots in a third portion of the plurality of slots to uplink communication or downlink communication in accordance with demand.
Claim 22
Dependent Claim
90 words
In a communication system adapted to communicate information in allocated frame slots on an uplink and downlink between a user and a base station in a cell, a method of allocating slots comprising the steps of: assigning a first portion of a plurality of slots in a frame for communication on the uplink; assigning a second portion of the plurality of slots for communication on the downlink; and dynamically allocating slots in a third portion of the plurality of slots to uplink communication or downlink communication in accordance with demand.
Claim 23
Dependent Claim
53 words
The method of claim 19 wherein the step of dynamically allocating slots in a third portion of the plurality of slots further includes allocating the slots such that a set of directional antennas at the base station receives uplink information in one order and transmits downlink information in another order within the frame.
Claim 24
Dependent Claim
119 words
In a communication system in which information is communicated in slots of a frame between a base station in a given system cell and users in that cell, an apparatus comprising: antenna means in the given cell arranged to transmit downlink information to the users in the given cell and to receive uplink information from the users in the given cell, wherein the antenna means includes a potentially-interfering antenna which can interfere with reception of uplink information in a frequency reuse cell; and means for allocating the slots to users in the given cell such that the potentially-interfering antenna transmits downlink information in different slots of the frame than those in which the frequency reuse cell receives uplink information.
Claim 25
Dependent Claim
119 words
In a communication system in which information is communicated in slots of a frame between a base station in a given system cell and users in that cell, an apparatus comprising: antenna means in the given cell arranged to transmit downlink information to the users in the given cell and to receive uplink information from the users in the given cell, wherein the antenna means includes a potentially-interfering antenna which can interfere with reception of uplink information in a frequency reuse cell; and means for allocating the slots to users in the given cell such that the potentially-interfering antenna transmits downlink information in different slots of the frame than those in which the frequency reuse cell receives uplink information.
Claim 26
Dependent Claim
13 words
The apparatus of claim 21 wherein the antenna means comprises an omnidirectional antenna.
Claim 27
Dependent Claim
15 words
The apparatus of claim 21 wherein the antenna means comprises a set of directional antennas.
Claim 28
Dependent Claim
62 words
The apparatus of claim 23 wherein the means for allocating the slots includes a processor adapted to receive status information identifying which of the directional antennas in the set is being used to communicate with a particular user in the given cell, and to direct the allocation of a slot to the particular user in accordance with a predetermined slot-direction frame organization.
Claim 29
Dependent Claim
41 words
The apparatus of claim 23 wherein the means for allocating the slots provides a slot allocation such that the directional antennas in the given cell receive uplink information in one order and transmit downlink information in another order within the frame.
Claim 30
Dependent Claim
125 words
In a communication system in which information is communicated in slots of a frame between a base station in a given system cell and users in that cell, a method of allocating the slots comprising the steps of: providing antenna means in the given cell arranged to transmit downlink information to the users in the given cell and to receive uplink information from the users in the given cell, wherein the antenna means includes a potentially-interfering antenna which can interfere with reception of uplink information in a frequency reuse cell; and allocating the slots to users in the given cell such that the potentially-interfering antenna transmits downlink information in different slots of the frame than those in which the frequency reuse cell receives uplink information.
Claim 31
Dependent Claim
125 words
In a communication system in which information is communicated in slots of a frame between a base station in a given system cell and users in that cell, a method of allocating the slots comprising the steps of: providing antenna means in the given cell arranged to transmit downlink information to the users in the given cell and to receive uplink information from the users in the given cell, wherein the antenna means includes a potentially-interfering antenna which can interfere with reception of uplink information in a frequency reuse cell; and allocating the slots to users in the given cell such that the potentially-interfering antenna transmits downlink information in different slots of the frame than those in which the frequency reuse cell receives uplink information.
Claim 32
Dependent Claim
24 words
The method of claim 26 wherein the step of providing antennas means includes providing a set of directional antennas which include the potentially-interfering antenna.
Claim 33
Dependent Claim
55 words
The method of claim 27 wherein the step of allocating the slots further includes the steps of: identifying which of the directional antennas in the set is being used to communicate with a particular user in the given cell; and allocating a slot to the particular user in accordance with a predetermined slot-direction frame organization.
Claim 34
Dependent Claim
42 words
The method of claim 27 wherein the step of allocating the slots further includes allocating the slots such that the directional antennas in the given cell receive uplink information in one order and transmit downlink information in another order within the frame.
Claim 35
Dependent Claim
17 words
The method of claim 26 wherein the step of providing antenna means includes providing an omnidirectional antenna.
Claim 36
Dependent Claim
191 words
A communication system for communicating information in slots of a frame, the system comprising: a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially-interfering antenna; a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information, wherein at least a portion of the slots in the frame are allocated dynamically such that given slots in the portion are allocated to either uplink or downlink communication in accordance with demand from the users in each of the cells.
Claim 37
Dependent Claim
191 words
A communication system for communicating information in slots of a frame, the system comprising: a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially-interfering antenna; a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information, wherein at least a portion of the slots in the frame are allocated dynamically such that given slots in the portion are allocated to either uplink or downlink communication in accordance with demand from the users in each of the cells.
Claim 38
Dependent Claim
65 words
The system of claim 31 wherein a first portion of the slots in the frame are assigned to uplink communication, a second portion of the slots in the frame are assigned to downlink communication, and a third portion of the slots in the frame are dynamically allocated to either uplink or downlink communication in accordance with demand from the users in each of the cells.
Claim 39
Independent Claim
195 words
A method of communicating information in allocated slots of a frame in a communication system, wherein the system includes a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the method comprising the steps of: providing a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, wherein the first base station includes a potentially-interfering antenna which can interfere with reception of uplink information in a potentially-interfered-with antenna in the second base station; and allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information, wherein the step of allocating the slots further includes the step of dynamically allocating slots in at least a portion of the frame to either uplink or downlink communication depending on demand from the users in each of the cells.
Claim 40
Independent Claim
195 words
A method of communicating information in allocated slots of a frame in a communication system, wherein the system includes a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the method comprising the steps of: providing a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, wherein the first base station includes a potentially-interfering antenna which can interfere with reception of uplink information in a potentially-interfered-with antenna in the second base station; and allocating the slots to users in each of the cells such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information, wherein the step of allocating the slots further includes the step of dynamically allocating slots in at least a portion of the frame to either uplink or downlink communication depending on demand from the users in each of the cells.
Claim 41
Independent Claim
154 words
An apparatus for communicating information in slots of a frame in a system including a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially interfering antenna, the apparatus comprising: a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in the frequency reuse cell such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
Claim 42
Independent Claim
154 words
An apparatus for communicating information in slots of a frame in a system including a first base station associated with a first cell and adapted to transmit downlink information to users in the first cell and to receive uplink information from users in the first cell, the first base station including a potentially interfering antenna, the apparatus comprising: a second base station associated with a frequency reuse cell and adapted to transmit downlink information to users in the frequency reuse cell and to receive uplink information from users in the frequency reuse cell, the second base station including a potentially-interfered-with antenna, wherein the potentially-interfering antenna can interfere with reception of uplink information in the potentially-interfered-with antenna; and means for allocating the slots to users in the frequency reuse cell such that the potentially-interfering antenna transmits downlink information in a different portion of the frame than that in which the potentially-interfered-with antenna receives uplink information.
References Cited (Backward Citations)
US4485486A
Cited
US4841521A
Cited
US4979170A
Cited
US4949335A
Cited
US5025442A
Cited
US5117423A
Cited
US5200956A
Cited
US4987571A
Cited
US5185739A
Cited
US5241542A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-14 | 2000-07-15 | 2001-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-14 | 2004-07-15 | 2005-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-14 | 2008-07-15 | 2009-01-14 | $7700.00 | Window Closed / Lapsed |