WO1997032440A1 - Selection de canaux audio tendant a eviter les interferences dans un systeme cellulaire a reutilisation de frequences - Google Patents

Selection de canaux audio tendant a eviter les interferences dans un systeme cellulaire a reutilisation de frequences Download PDF

Info

Publication number
WO1997032440A1
WO1997032440A1 PCT/SE1997/000306 SE9700306W WO9732440A1 WO 1997032440 A1 WO1997032440 A1 WO 1997032440A1 SE 9700306 W SE9700306 W SE 9700306W WO 9732440 A1 WO9732440 A1 WO 9732440A1
Authority
WO
WIPO (PCT)
Prior art keywords
frequency
voice channel
cell
assigned
cellular
Prior art date
Application number
PCT/SE1997/000306
Other languages
English (en)
Inventor
Daniel Dulong
Richard Brunner
Chong Nguyen
Original Assignee
Telefonaktiebolaget Lm Ericsson (Publ)
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Telefonaktiebolaget Lm Ericsson (Publ) filed Critical Telefonaktiebolaget Lm Ericsson (Publ)
Priority to AU21085/97A priority Critical patent/AU2108597A/en
Publication of WO1997032440A1 publication Critical patent/WO1997032440A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/02—Resource partitioning among network components, e.g. reuse partitioning
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/02—Resource partitioning among network components, e.g. reuse partitioning
    • H04W16/12—Fixed resource partitioning
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/56—Allocation or scheduling criteria for wireless resources based on priority criteria
    • H04W72/563—Allocation or scheduling criteria for wireless resources based on priority criteria of the wireless resources
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/02—Resource partitioning among network components, e.g. reuse partitioning
    • H04W16/04—Traffic adaptive resource partitioning
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/14—Spectrum sharing arrangements between different networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/02—Selection of wireless resources by user or terminal
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H04W72/044—Wireless resource allocation based on the type of the allocated resource
    • H04W72/0453—Resources in frequency domain, e.g. a carrier in FDMA
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/54—Allocation or scheduling criteria for wireless resources based on quality criteria
    • H04W72/541—Allocation or scheduling criteria for wireless resources based on quality criteria using the level of interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks
    • H04W84/042—Public Land Mobile systems, e.g. cellular systems

Definitions

  • the present invention relates to cellular telephone systems and, in particular, to a method and apparatus for effectuating efficient voice channel selection with reduced interference.
  • Cellular telephone systems divide a large service area into a number of smaller discrete geographical areas called "cells" each typically ranging in size from about one-half to about twenty kilometers in diameter. Each cell is contiguous with multiple adjacent cells to provide continuous coverage throughout the service area.
  • a base station including a plurality of transceivers capable of operating independently on different radio frequencies is provided for each of the cells. Via the transceivers, the base stations engage in simultaneous communications with plural mobile stations operating within the area of the associated cell.
  • the base stations further communicate via data links (and voice trunks) with a central control station, commonly referred to as a mobile switching center, which functions to selectively connect telephone calls to the mobile stations through the base stations and, in general, control operation of the system.
  • Each cell is assigned use of a predetermined set of frequencies from the cellular frequency band for use in providing its analog and/or digital voice channels.
  • the availability of multiple voice channels per cell permits base stations to simultaneously handle many telephone conversations with many mobile stations.
  • the frequencies used for the voice channels assigned to a given cell are preferably spaced apart from each other across the frequency spectrum of the cellular frequency band. This serves to minimize the instances and adverse affects of adjacent channel interference.
  • the same frequencies that are assigned to one cell are also assigned to (i.e., reused by) other cells in distant parts of the service area.
  • adjacent cells are not assigned to use the same frequency.
  • the power levels of the signal transmissions on any given frequency are limited in strength so as to limit propagation beyond the cell area. The foregoing precautions serve to reduce instances of co-channel interference caused by reuse of that same frequency in a distant cell.
  • the mobile switching center functions to dynamically allocate the voice channels (comprising the assigned voice frequencies in analog systems or time slots therein for digital systems) available in any one cell among the plurality of mobile stations located within the cell area that desire communications.
  • Commands that allocate for mobile station use a certain voice channel assigned to a given cell are transmitted from the mobile switching center to the base station for that cell.
  • the commands are then relayed by the base station to the certain mobile station over one of the assigned frequencies to direct mobile station access to the allocated voice channel for handling the call.
  • Allocation by the mobile switching center of a particular voice channel in a cell to a particular mobile station for a call primarily occurs in two instances.
  • the first instance is at call set-up when the subscriber activates the mobile station to initiate (i.e., originate or terminate) a call and the system selects the voice channel to carry that call.
  • the second instance is at call hand-off when the subscriber, while engaged in a call, moves from one cell in the service area to another cell, and the system allocates a voice channel in the new cell to handle the on-going call.
  • AMPS advanced mobile phone system
  • GSM Global System for Mobile
  • the cellular frequency band is divided into a plurality of groups of frequencies, with each group assigned to multiple cells.
  • the groups of frequencies are then partitioned into a plurality of sub-sets of frequencies, with the sub ⁇ sets within each frequency group individually prioritized on a cell-by-cell basis such that proximately located cells reusing the same frequency group have differing frequency sub-set prioritizations.
  • the system gives preference within each cell to those voice channels associated with frequencies assigned to that cell having a higher sub-set prioritization. By allocating voice channels in this fashion, communications load is spread efficiently across the cellular frequency band, and the risk of instances of co-channel interference is minimized.
  • the cellular frequency band is again divided into a plurality of groups of frequencies, with each group assigned to multiple cells.
  • the system determines whether a chosen one of the voice channels is concurrently being used in a proximately located cell that reuses the same frequency group.
  • an alternate voice channel is chosen and subjected to the concurrent use analysis. Allocation of a voice channel is not made until the system finds that the chosen voice channel is not concurrently being used in any of the proximately located cells reusing the same frequency group.
  • FIGURE 1 is an exemplary cell diagram schematically illustrating the frequency assignment architecture of a frequency reuse cellular telephone system
  • FIGURE 2 illustrates the division of the cellular frequency band into groups of frequencies, with the frequency groups being distributed amongst the cells in one given cluster;
  • FIGURE 3 illustrates the division of a group of frequencies into sub-sets of frequencies, as well as the differing prioritization of the sub-sets across a plurality of cells that are assigned use of the same frequency group;
  • FIGURE 4 is a flow diagram for the allocation of voice channels in accordance with the sub-set prioritization illustrated in FIGURE 3;
  • FIGURE 5 is a flow diagram for the allocation of voice channels depending on detection of concurrent use in a proximate cell assigned use of the same frequency group.
  • radio frequencies in the cellular frequency band available to cellular telephone system providers for use in communicating with mobile stations. A majority of the available radio frequencies are reserved for the voice channels used in carrying telephone calls.
  • an analog cellular telephone system like the known advanced mobile phone system (AMPS)
  • FDMA frequency division multiple access
  • FDMA digital voice channels time slots
  • the remaining radio frequencies in the cellular frequency band are reserved as control channels for carrying the control signals
  • control channel comprises one time slot on a frequency shared with plural voice channels .
  • the control signals transmitted over the control channel comprise call originations, page signals, page response signals, location registration signals, voice channel assignments, maintenance instructions, and cell selection or reselection instructions.
  • a common cellular system frequency assignment architecture provides for a normal frequency band plus an extended frequency band within the overall cellular frequency band.
  • a first plurality of the radio frequencies in the normal band portion of the cellular frequency band are reserved for the control channels utilized by the system on an at least one control channel per cell basis to carry cellular system operation control signals and messages between mobile stations and base stations.
  • a second plurality of the frequencies from both the normal and extended bands are reserved for the voice channels, and are typically divided more or less equally amongst the cells and allocated on as needed basis by the system to subscribers for carrying cellular voice communications between mobile stations and base stations.
  • a cellular service area can cover a large geographic region, and in many instances there will be a need for a large number of cells. Often times, the number of cells needed exceeds in number the number of cells provided by dividing the available frequencies amongst the cells in such a manner as to handle expected subscriber usage per cell. In such a case there are simply not enough frequencies in the cellular frequency band for unique assignment to the included cells. Accordingly, in order to provide sufficient call handling capacity throughout the service area, the cells are grouped into clusters of cells and the frequencies in the cellular frequency band are divided amongst and reused in each of the clusters . Reference is now made to FIGURE 1 wherein there is illustrated a known cell structure and frequency assignment architecture for use in a radio frequency reuse cellular telephone system.
  • each cluster 12 includes seven cells 10(1) -10 (7) . It will, of course, be understood that each cluster 12 may have more or less cells 10 as needed.
  • the available frequencies in the cellular frequency band are divided in accordance with the frequency assignment architecture into groups of frequencies 14, with the frequency groups distributed amongst the cells 10 of each cluster 12 such that the radio frequencies of the cellular band are reused in each cluster.
  • groups of frequencies 14 For example, in a cell structure having seven cells 10 per cluster 12 like that shown in FIGURE 1, there are seven frequency groups 14 identified and differentiated from each other by the alphabetic labels "A" through "G" corresponding to the cells 10(1) -10 (7) , respectively.
  • each cell 10(1) in the service area is assigned use of radio frequencies in frequency group A
  • each cell 10(2) is assigned use of radio frequencies in frequency group B
  • the first seven of the frequencies fl-f7 are reserved as analog control channels, assigned one each to the groups of frequencies 14 A through G, respectively, and distributed one control channel per cell to cells 10(1)- 10(7) .
  • the first control channel radio frequency fl in frequency group 14 A is assigned to each cell 10(1)
  • control channel frequency f2 in frequency group B is assigned to cell 10(2)
  • control channel frequency f7 in frequency group G being assigned to cell 10(7)
  • the remaining radio frequencies f8-f28 are reserved as analog voice channels, and are divided equally into the frequency groups 14 A through G, and distributed amongst the cells 10(1) -10 (7) to provide three voice channels per cell.
  • each of the cells 10(1) across the service area is assigned frequency group 14 A including control channel radio frequency fl, and voice channel frequencies f8, fl5 and f22.
  • adjacent cells are typically not assigned use of the same radio frequency.
  • Reuse of an identical radio frequency in the service area is preferably made with a separation of at least one cell 10 along with a regulation of broadcast power from each cell to constrain radio propagation substantially within the cell area.
  • typically no one cell 10 utilizes adjacent radio frequencies in the cellular band. Adjacent radio frequencies are preferably assigned no closer than one cell 10 away each other.
  • interference does occur in cellular systems like that previously described.
  • One aspect of this interference originates from same analog or digital channel communications occurring simultaneously in the cells 10 of other clusters 12 (i.e., co-channel interference) .
  • co-channel interference i.e., co-channel interference
  • Each of the cells 10 in a cellular system such as that illustrated in FIGURE 1 includes at least one base station (BS) 18 configured to facilitate radio frequency communications with mobile stations 20 moving throughout the service area.
  • the base stations 18 are illustrated as being positionally located at or near the center of each of the cells 10. However, depending on geography and other known factors, the base stations 18 may instead be located at or near the periphery of, or otherwise away from the centers of, each of the cells 10. In such instances, the base stations 18 may broadcast and communicate with mobile stations 20 located within the cells 10 using directional rather than omni-directional antennas.
  • the base stations 18 are connected by communications links (generally shown by arrow 21) to at least one mobile switching center (MSC) 22 operating to control the operation of the system for providing cellular communications with the mobile stations 20.
  • MSC mobile switching center
  • FIGURE 2 wherein there is shown a schematic illustration of the distribution of the groups of frequencies 14 (A through G) amongst the cells 10(1) -10 (7) in one given cluster 12.
  • the cellular frequency band includes frequencies in both a normal frequency band and frequencies in an extended frequency band.
  • each frequency group acquires both normal band (nb) frequencies 16 and extended band (eb) frequencies 17.
  • the mobile stations 20 operable in the system of FIGURE 1 may comprise mobile stations configured for voice channel operation only on those frequencies of the normal frequency band (nb) 16, or alternatively comprise mobile stations capable of voice channel operation over frequencies in both the normal frequency band and the extended frequency band (eb) 17. In the case of mobile stations 20 operable over both bands, preference for operation is typically made in the system for use of the extended frequency band 17.
  • the cellular frequency assignment architecture of the present invention partitions each of the frequency groups 14 into a plurality of sub-sets of frequencies with the frequency sub-sets being individually (i.e., differently) prioritized at least with respect to proximately located cells 10.
  • These frequency sub-sets may comprise as many different frequencies as desired, including as few as one frequency per sub-set.
  • proximately located cells 10 that are assigned reuse of the same frequency group 14 emphasize allocation of different frequencies in the cellular frequency band to the mobile stations 20 for use as their analog or digital voice channels.
  • the partitioning of the frequency groups 14 and prioritization of the frequency sub-sets in accordance with the cellular frequency assignment architecture of the present invention may be better understood by referring to FIGURE 3 in connection with the specific cellular frequency architecture example previously described and shown in FIGURE 1.
  • the frequency groups 14 (A through G) are partitioned into n frequency sub-sets 24 (A(l)-A(n) through G(l)-G(n)) each. It will, of course, be understood that the number (n) of sub-sets 24 may be different for each frequency group 14 if necessary.
  • FIGURE 3 illustrates the partitioning of one frequency group 14 A with respect to the cells 10(1) of clusters 12(1) -12 (4) for the system of FIGURE 1 into n frequency sub-sets 24 (A(l)-A(n)) . Similar partitions (not shown) are made with respect to the remaining frequency groups 14 for the cells 10 (2) -10 (7) in the cluster 12.
  • the prioritization of the frequency sub-sets 24 preferably differs across the plurality of cells 10 assigned the same frequency group, and at a minimum differs with respect to proximately located cells.
  • cell 10(1) of cluster 12(1) gives priority for mobile station allocation to the frequencies in sub ⁇ set 24 A(l)
  • proximately located cell 10(1) of cluster 12(2) gives priority for mobile station allocation to the frequencies in sub-set 24 A(2)
  • Similar prioritizations are made with respect to the frequency sub-sets 24 within the frequency groups 14 assigned to cells 10 (2) -10 (7) .
  • the system gives preference within each cell 10 to the channels associated with those frequencies assigned to that cell having a higher frequency sub-set 24 prioritization.
  • a preference is given to allocating voice channels to a mobile station 20 in cell 10(1) of cluster 12(1) in those frequencies that are within sub-set 24 A(l) than in any other frequencies within the assigned frequency group 14 A because such frequencies have a higher sub-set priority.
  • a mobile station in cell 10(1) of cluster 12(4) is more likely to be allocated a voice channel associated with a frequency within sub-set 24 A(4) than in any other frequencies due to the provided sub-set prioritization.
  • a preference is then given to allocating voice channels associated with frequencies in the next highest priority sub-set 24.
  • FIGURE 4 is a flow diagram for cellular system operation in controlling the allocation of voice channels in accordance with the cellular frequency assignment architecture of FIGURE 1 and the sub-set prioritization, illustrated in FIGURE 3.
  • the system preferably operating by and through one of its mobile switching centers 22
  • step 100 the highest priority sub-set of frequencies for the frequency group assigned to the cell which is serving the mobile station.
  • step 102 An available voice channel associated with the selected sub-set of frequencies is then chosen in step 102 as the voice channel for the mobile station communication. If this operation is successful (as determined in decision step 104), the allocation process ends in step 106 with the chosen voice channel being allocated to the mobile station. If, on the other hand, the operation of step 102 is unsuccessful (again determined by step 104) , perhaps because all of the voice channels in the selected sub-set of frequencies are currently in use by other mobile stations, the system selects in step 108 a next highest priority sub-set of frequencies from the frequency group assigned to the cell which is serving the mobile station.
  • the allocation process then returns to step 102 to choose an available voice channel in the selected sub-set of frequencies, and the process repeats itself, as often as necessary, until an available voice channel is found.
  • step 102 When the operation of step 102 is unsuccessful and there are no more sub-sets of frequencies to select from (branch
  • the system has then failed to find an available voice channel in the cellular frequency band to be allocated and the hand-off or call set up channel allocation fails in step 112.
  • the system in allocating a voice channel in accordance with the process of FIGURE 4 may be better understood with reference to the prioritization of FIGURE 3 and a specific example wherein a mobile station is located in cell 10(1) of cluster 12(2) and desires to originate a cellular call.
  • the system preferably operating through one of its mobile switching centers 22
  • An available voice channel in frequency sub-set 24 A(2) is then chosen (step 102) to be allocated for handling the mobile station call (step 106) . If there are no available voice channels in sub-set 24 A(2) as determined in step 104, the system selects (step 108) frequency sub-set 24 A(3) because it has the next highest priority for cell 10(1) of cluster 12(2).
  • the voice channel availability determination is then made again
  • step 102 with the process repeating itself and considering frequency sub-sets 24 with lower and lower priority until an available voice channel is found (step 106) , or the assigned frequency sub-sets 24 available for consideration are exhausted (branch 110) .
  • step 114 one of the available voice channels within the selected frequency sub-set is chosen.
  • available it is meant that the chosen voice channel is not currently being used by any other mobile stations in that particular cell.
  • decision step 116 A determination is then made in decision step 116 as to whether the chosen voice channel is concurrently being used by another mobile station in a proximately located cell that has been assigned to the same frequency group. If the answer is yes (branch 118) , then the process returns to step 114 to choose a different voice channel within the selected frequency sub-set.
  • step 116 If the answer to decision step 116 is instead no (branch 120) , then the chosen voice channel is allocated in step 122 to the base station for carrying a cellular communication. Steps 114 and 116 are repeated until an available voice channel (i.e., not currently in use in that cell or in a proximately located cell) is found and allocated to the mobile station. By allocating voice channels in this fashion, communications load is spread efficiently across the cellular frequency band, and the risk of instances of co-channel interference is minimized.
  • an available voice channel i.e., not currently in use in that cell or in a proximately located cell
  • the process of FIGURE 5 is disclosed as being a part of the sub-set analysis and voice channel allocation process of FIGURE 4, it will be understood that the process of FIGURE 5 may be implemented by the system (e.g., mobile switching center 22) independently of the allocation process of FIGURE 4.
  • the voice channel chosen in step 112 is instead chosen from the entire frequency group assigned to the cell rather than from only one selected sub-set of frequencies as has previously been described. In either case, the method is effective in providing for the selection of a voice channel with reduced interference.
  • step 114 a voice channel not currently in use within the cell 10(1) of cluster 12(2) which is then serving the mobile station 20.
  • the determination of step 116 involves evaluating concurrent use of the chosen voice channel in the proximately located (i.e., neighboring) cells 10(1) of clusters 12(1) , 12(3) and 12(4) . Assume now that the chosen voice channel is in fact being used in cell 10(1) of cluster 12(3) .
  • the determination step 116 thus finds concurrent use and the system returns (via branch 118) to choose another voice channel in step 114. If instead no other mobile station was using the voice channel in a neighboring cell, the determination step 116 fails to find concurrent use, and the voice channel is allocated (Step 122) to the mobile station.

Abstract

La bande de fréquence cellulaire accueillant une série de canaux audio est divisée en plusieurs groupes de fréquence ([A] - [G]) assigné chacun (c'est-à-dire reutilisé à l'intérieur de plusieurs cellules) d'un système téléphonique cellulaire. Le canal audio attribué à une station mobile (20) comprend le canal choisi dans le groupe de fréquence destiné à la cellule (10) où la station mobile se trouve au moment donné qui n'a pas été concurrement attribué (116) à une autre station mobile se trouvant dans une cellule contiguë à laquelle est également assigné le même groupe de fréquence. Les groupes de fréquence peuvent en outre être divisés en plusieurs sous-ensemble (24) dont chacun est individuellement affecté d'une priorité sur la base de chaque cellule de telle sorte que de cellules contiguës réutilisant le même groupe de fréquence ont des ordres de priorité différents pour les sous ensembles. Au moment de l'attribution du canal, la préférence est accordée aux canaux destinés à la cellule où la station mobile se trouve au moment considéré qui revêtent le degré de priorité le plus élevé quant aux sous-ensemble. Une telle utilisation concurrente et une telle analyse de priorité contribue à étaler de manière efficace la charge de communication sur l'ensemble des bandes de fréquence de la cellule et à réduire la risque des interférences entre les voies.
PCT/SE1997/000306 1996-02-27 1997-02-24 Selection de canaux audio tendant a eviter les interferences dans un systeme cellulaire a reutilisation de frequences WO1997032440A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU21085/97A AU2108597A (en) 1996-02-27 1997-02-24 Voice channel selection for reduced interference in a frequency reuse cellular system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US60780896A 1996-02-27 1996-02-27
US08/607,808 1996-02-27

Publications (1)

Publication Number Publication Date
WO1997032440A1 true WO1997032440A1 (fr) 1997-09-04

Family

ID=24433794

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1997/000306 WO1997032440A1 (fr) 1996-02-27 1997-02-24 Selection de canaux audio tendant a eviter les interferences dans un systeme cellulaire a reutilisation de frequences

Country Status (3)

Country Link
AR (1) AR006017A1 (fr)
AU (1) AU2108597A (fr)
WO (1) WO1997032440A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000035222A1 (fr) * 1998-12-07 2000-06-15 Marconi Communications Israel Ltd. Dispositif et procedes d'attribution de voies
WO2003101135A1 (fr) * 2002-05-27 2003-12-04 Koninklijke Philips Electronics N.V. Systeme d'attribution de canaux a des appels avec ordre de priorite actualisable
US6788943B1 (en) 1997-09-17 2004-09-07 Nokia Mobile Phones Ltd. Channel allocation in the base stations of a cellular radio system
WO2006085194A1 (fr) * 2005-02-08 2006-08-17 Nokia Corporation Dispersion de couche de frequence
EP2299763A1 (fr) * 2009-09-17 2011-03-23 Samsung Electronics Co., Ltd. Procédé et appareil pour la transmission et la réception d'un message d'appel dans un système de communication à superposition de fréquence
US8520608B2 (en) * 2006-06-19 2013-08-27 Ntt Docomo, Inc. Mobile communication system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0441372A2 (fr) * 1990-02-08 1991-08-14 Nec Corporation Méthode pour l'affectation optimale d'un canal dans un système de radio-communications multi-stations
WO1995007013A1 (fr) * 1993-09-01 1995-03-09 Telefonaktiebolaget Lm Ericsson Selection de voies dans un systeme de communications cellulaire

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0441372A2 (fr) * 1990-02-08 1991-08-14 Nec Corporation Méthode pour l'affectation optimale d'un canal dans un système de radio-communications multi-stations
WO1995007013A1 (fr) * 1993-09-01 1995-03-09 Telefonaktiebolaget Lm Ericsson Selection de voies dans un systeme de communications cellulaire

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
LEE W C Y: "SMALLER CELLS FOR GREATER PERFORMANCE", IEEE COMMUNICATIONS MAGAZINE, vol. 29, no. 11, 1 November 1991 (1991-11-01), pages 19 - 23, XP000279120 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6788943B1 (en) 1997-09-17 2004-09-07 Nokia Mobile Phones Ltd. Channel allocation in the base stations of a cellular radio system
WO2000035222A1 (fr) * 1998-12-07 2000-06-15 Marconi Communications Israel Ltd. Dispositif et procedes d'attribution de voies
WO2003101135A1 (fr) * 2002-05-27 2003-12-04 Koninklijke Philips Electronics N.V. Systeme d'attribution de canaux a des appels avec ordre de priorite actualisable
WO2006085194A1 (fr) * 2005-02-08 2006-08-17 Nokia Corporation Dispersion de couche de frequence
JP2008530843A (ja) * 2005-02-08 2008-08-07 ノキア コーポレイション 周波数層分散
AU2006213557B2 (en) * 2005-02-08 2010-06-10 Nokia Corporation Frequency layer dispersion
US8520608B2 (en) * 2006-06-19 2013-08-27 Ntt Docomo, Inc. Mobile communication system
EP2299763A1 (fr) * 2009-09-17 2011-03-23 Samsung Electronics Co., Ltd. Procédé et appareil pour la transmission et la réception d'un message d'appel dans un système de communication à superposition de fréquence
US8055281B2 (en) 2009-09-17 2011-11-08 Samsung Electronics Co., Ltd Method and apparatus for transmitting and receiving a paging message in a frequency overlay communication system

Also Published As

Publication number Publication date
AU2108597A (en) 1997-09-16
AR006017A1 (es) 1999-07-21

Similar Documents

Publication Publication Date Title
CA2249582C (fr) Procede et appareil pour reduire les interferences dans un meme canal
US5963865A (en) Traffic channel assignment in a cellular telephone system using an uplink interference driven frequency packing method
US6418317B1 (en) Method and system for managing frequencies allocated to a base station
US6295453B1 (en) Multi-full rate channel assignment for a cellular telephone system
US6104930A (en) Floating transceiver assignment for cellular radio
US5896573A (en) Channel assignment selection reducing call blocking and call cutoff in a cellular communication system
US5732353A (en) Automatic control channel planning in adaptive channel allocation systems
US6002935A (en) Wireless communications cellular architecture for improving communications resource allocation
US6006092A (en) Quality driven voice channel selection in a cellular telephone system using idle voice channel signal strength measurements
EP0733297B1 (fr) Partage des canaux dans un systeme mixte macro/microcellulaire
EP0482050B1 (fr) Systeme radio cellulaire
WO1997032440A1 (fr) Selection de canaux audio tendant a eviter les interferences dans un systeme cellulaire a reutilisation de frequences
GB2318483A (en) Dynamic Control of Cellular Radio Communication System Resources
WO2000067394A2 (fr) Systeme et procede permettant un usage efficace de la puissance de diffusion tout en reduisant les brouillages des sites de cellules dans la meme voie
US6374111B1 (en) System and method for robust automatic cell retune
US20040057406A1 (en) Enhanced high traffic density CDMA wireless systems
Hong et al. An innovative channel management strategy for highly reliable handoff in cellular networks
CA2299304A1 (fr) Procede et dispositif de reconfiguration d'un canal de commande dans un systeme telephonique cellulaire
MXPA00005043A (en) Traffic channel assignment in a cellular telephone system using an uplink interference driven frequency packing method
MXPA99003325A (en) Method for improving co-channel interference in a cellular system

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG UZ VN YU AM AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 97530860

Format of ref document f/p: F

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase