WO1994007322A1 - Procede et appareil de commande de transmission dans un systeme de radiotelephone - Google Patents

Procede et appareil de commande de transmission dans un systeme de radiotelephone Download PDF

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Publication number
WO1994007322A1
WO1994007322A1 PCT/US1993/008780 US9308780W WO9407322A1 WO 1994007322 A1 WO1994007322 A1 WO 1994007322A1 US 9308780 W US9308780 W US 9308780W WO 9407322 A1 WO9407322 A1 WO 9407322A1
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WIPO (PCT)
Prior art keywords
information
cell
control
control channel
relative
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Application number
PCT/US1993/008780
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English (en)
Inventor
Alex Krister Raith
Walter G. A. Muller
Original Assignee
Telefonaktiebolaget Lm Ericsson
Ericsson Ge Mobile Communications Inc.
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.)
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=27130224&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO1994007322(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from US07/955,591 external-priority patent/US5353332A/en
Application filed by Telefonaktiebolaget Lm Ericsson, Ericsson Ge Mobile Communications Inc. filed Critical Telefonaktiebolaget Lm Ericsson
Priority to GB9409631A priority Critical patent/GB2275589B/en
Priority to CA002123605A priority patent/CA2123605C/fr
Priority to KR1019940701638A priority patent/KR100277558B1/ko
Priority to AU49267/93A priority patent/AU668591B2/en
Publication of WO1994007322A1 publication Critical patent/WO1994007322A1/fr
Priority to SE9401644A priority patent/SE517898C2/sv
Priority to HK98105574A priority patent/HK1006623A1/xx

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W48/00—Access restriction; Network selection; Access point selection
    • H04W48/20—Selecting an access point
    • 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
    • H04W16/24—Cell structures
    • H04W16/32—Hierarchical cell structures

Definitions

  • the present invention relates to a control technique for a radiotelephone communication system, and more particularly, to a control technique for a wireless communication system.
  • Interference between communications in cells located near one another creates additional problems, particularly when relatively small cells are utilized. Thus, techniques are necessary for minimizing interference between cells.
  • One known technique is to group cells into "clusters". Within individual clusters, communication frequencies are allocated to particular cells in a manner which attempts to maximize the uniform distance between cells in different clusters which use the same communication frequencies. This distance may be termed the "frequency reuse" distance. As this distances increases, the interference between a cell using a communication frequency and a distant cell using that same frequency is reduced.
  • Radio base stations are often located near the center of each cell to provide radio coverage throughout the area of the cell.
  • a radio base station may be located near the center of three adjacent "sector cells" to cover those cells.
  • the choice between a sectorized and non-sectorized system is based on various economical considerations such as equipment costs for each base station.
  • microcells and picocells may be established within overlying macrocells to handle areas with relatively dense concentrations of mobile users, sometimes referred to as "hot spots".
  • microcells may be established for thoroughfares such as crossroads or streets, and a series of microcells may provide coverage of major traffic arteries such as highways.
  • Microcells may also be assigned to large buildings, airports and shopping malls.
  • Picocells are similar to microcells, but normally cover an office corridor or a floor of a high-rise building.
  • the term "microcells” is used in this application to denote both microcells and picocells, and the term “macrocells” is used to denote the outermost layer of a cellular structure.
  • An "umbrella cell” can be a macrocell or a microcell as long as there is a cell underlying the umbrella cell. Microcells allow additional communication channels to be located in the vicinity of actual need, thereby increasing overall system capacity while maintaining low levels of interference.
  • Macrocell umbrella sites typically cover radii in excess of one kilometer and serve rapidly moving users, for example, people in automobiles.
  • Microcell sites are usually low power, small radio base stations, which primarily handle slow moving users, such as pedestrians.
  • Each microcell site can be viewed as an extended base station which is connected to a macrocell site through digital radio transmission or optical fibers.
  • allocated spectrum must be distributed to individual microcell sites.
  • Known methods employed for spectrum allocation include fixed frequency planning, dynamic channel allocation (DCA) , and adaptive channel allocation (ACA) .
  • DCA dynamic channel allocation
  • ACA adaptive channel allocation
  • a control channel management technique must be selected. One possibility includes having each cell or sector in a sectorized system use a unique control channel until frequency reuse is feasible from an interference point of view.
  • microcells radio network planning may increase in complexity. The planning process is largely dependent upon the structure of the microcells. For example, the size of streets, shopping malls, and buildings are key design criteria. Microcells suffer from a series of problems including an increased sensitivity to traffic variations, interference between microcells, and difficulty in anticipating traffic intensities. Even if a fixed radiotelephone communication system could be successfully planned, a change in system parameters such as adding a new base station to accommodate increased traffic demand may require replanning the entire system. For these reasons, the introduction of microcells benefits from a system in which channel assignment is adaptive both to traffic conditions and to interference conditions.
  • ACA adaptive channel allocation
  • ACA schemes attempt to improve traffic capacity and avoid the need for frequency planning. While some systems have been moderately effective in accomplishing these goals, it has been difficult to achieve both goals in a system which has preassigned control channels, i.e., a system having specified frequencies on which a mobile station may expect a control channel (e.g., a 30 KHz RF channel which contains control signals) .
  • Systems having preassigned control channels include AMPS (Advanced Mobile Phone Service System) , IS-54 (Revision B) and TACS (Total Access Communication System) . In such systems, frequency planning is still needed for control channels. However, frequency planning for voice channels can be avoided and traffic capacity improved by eliminating the need to plan a number of voice channels on each site in an area where traffic channels are expected to be non-uniformly distributed.
  • the aim of such a system is to assign as many mobiles as possible to microcell control channels by maintaining those control channels stronger than the control channels of the umbrella macrocell in the intended microcell area while transmitting with a sufficiently low power to avoid interference with the distant macrocell.
  • Power or interference limitations can result in a voice channel limited system where some of the mobiles in the microcells will receive a stronger signal from an overlying macrocell.
  • the number of mobiles receiving a stronger signal from an overlying macrocell will increase as the distance between the umbrella cell and the microcell decreases. Consequently, capacity might not increase since mobiles are locked-on to the macrocell.
  • the battery life of the current portables would correspondingly decrease to maintain the equivalent level of performance.
  • blocking and intermodulation may arise with high powered mobiles located inside the microcell area.
  • the high-powered mobiles are power controlled by the umbrella macrocell and require more power to communicate with the umbrella macrocell than the microcell.
  • a control channel management scheme implemented according to the present invention may include a variety of different cells.
  • the control channel of each cell can be configured to broadcast information about other cells including the characteristics of the cells such as cell type. Further, the location in frequency and time of other control channels may also be included among the information broadcast over a control channel of a particular cell. This information is then used by the mobile to lock to a preferred cell. Locking is the selecting of a cell such that a mobile reads all messages and is prepared to receive pages and make calls. Thus, once a mobile is locked to a particular cell, it may make and receive calls.
  • the mobile Based on the control information found on a control channel, the mobile attempts to find the best server, i.e., the best cell, based on both the mobile and system requirements.
  • the best server is the one which requires the mobile to transmit with the least amount of power.
  • the goal may be to minimize the charge of a call to a customer, thus the cell which provides the lowest cost service to the mobile may be selected.
  • criteria may be used to determine a preferred cell, and all such criteria are considered within the scope of this invention. In general, the preferred cell is determined by the system requirements and goals.
  • Fig. 1 is a cell plan illustrating two cell clusters in a cellular mobile radiotelephone system
  • Fig. 2 illustrates a typical multi-layered cellular system employing umbrella macrocells, microcells and picocells;
  • Fig. 3 illustrates a typical control channel
  • Fig. 4 represents an exemplary implementation of an apparatus for a radiotelephone system according to the present invention.
  • Fig. 1 illustrates a first cell cluster A and a second cell cluster B forming part of a cellular mobile radio telephone system in a known manner.
  • a system is described in U.S. Patent No. 5,230,082 entitled “Method and Apparatus For Enhancing Signalling Reliability in a Cellular Mobile Radio Telephone System” by Ghisler et al. which is incorporated herein by reference.
  • all frequencies available in a system are used in each cell cluster.
  • the frequencies are allocated to different cells to achieve the greatest uniform distance, known as the frequency reuse distance, between cells in different clusters using the same frequency.
  • cells A, and B use a common frequency
  • cells A 2 and B 2 use a common frequency
  • cells A 3 and B j use a common frequency
  • the radio channels in cells A, and B, using the same frequency are referred to as co-channels because they share the same frequency.
  • the level of such interference in an arrangement such as that of Fig. 1 is normally acceptable.
  • the cell plan of Fig. 1 allows for a relatively simple frequency allocation and provides reduced co-channel interference in low traffic conditions.
  • limitations in high traffic areas restrict the use of this cell plan. For example, traffic in hot spots can produce blocking.
  • Future systems may not require the type of frequency planning associated with the cell structure of Fig. 1.
  • a CDMA (code division multiple access) system may have very different assignment techniques and may not require frequency planning. However, transmitter power planning may be a concern instead.
  • channels may not need to be reused as described with reference to Fig. 1.
  • CDMA systems are shown in U.S. Patents No. 5,151,919 and No. 5,218,619, both entitled "CDMA Subtractive Demodulation" which are herein incorporated by reference.
  • techniques such as ACA may be used so that strict frequency planning is not necessary, in particular pre ⁇ planning, i.e., planning without knowledge of instantaneous conditions including traffic patterns and interference distribution.
  • Fig. 2 is an exemplary multi-layered cellular system.
  • An umbrella macrocell 10 represented by a hexagonal shape makes up an overlying cellular structure.
  • Each umbrella cell may contain an underlying microcell structure.
  • the umbrella cell 10 includes microcell 20- represented by the area enclosed within the dotted line and microcell 30 represented by the area enclosed within the dashed line corresponding to areas along city streets, and microcells 40, 50, and 60, which cover individual floors of a building.
  • the intersection of the two city streets covered by the microcells 30 and 40 may be an area of dense traffic concentration, and thus might represent a hot spot.
  • control channels are used for setting up calls, informing the base stations about locations and parameters associated with mobile stations, and informing the mobile stations about locations and parameters associated with the base stations.
  • the microcell base stations listen for call access requests by mobile stations and the mobile stations in turn listen for paging messages. Once a call access message has been received, it must be determined which cell will be responsible for the call. Future systems will employ additional cells. For example, new systems may include any combination of macrocells, indoor microcells, outdoor microcells, public microcells and restricted or private microcells. New systems therefore will likely be designed to incorporate an increasing number of control channels. Currently, there are approximately twenty-one control channels available for a cluster in a typical system employed in the United States.
  • each control channel in each cell is configured to broadcast information about the presence, if any, of other cells and the characteristics of those cells including minimum quality criteria, power requirements, etc.
  • information about the presence of other cells is broadcast about neighboring cells.
  • a neighboring cell may be adjacent to, overlapping, or non ⁇ contiguous with the broadcasting cell.
  • a mobile periodically scans during idle mode the control channels in the coverage area that the mobile is located in to determine which cell it should be locked to.
  • a mobile may continuously select cells to be locked to based on the existing location of the mobile and quality criteria (e.g., received signal strength) associated with the cells.
  • the cell to which the mobile may be locked is the cell in which the mobile satisfies the quality criteria associated with the cell. For example, the most underlying cell based on capacity considerations may be preferred by the mobile.
  • Absolute information includes information about the particular cell corresponding to the control channel on which the information is being broadcast. This information might include the service profile of that cell, the control channel organization, and/or the type of cell (for example restricted or unrestricted) .
  • An unrestricted cell is a cell which is available to all users at all times and a restricted cell is the opposite.
  • Relative information is generally the same kind of information as absolute information, but is information concerning the characteristics of other cells.
  • the mobile may be paged at any time, therefore the mobile must be locked to a particular cell in a location area so that the mobile may receive the page. For example, if the mobile has moved out of the location area of a first cell to which the mobile was locked to a second cell in a different location area, a paging request for the mobile will not be heard or received because the mobile switching center, or MSC, will page the mobile over a paging channel available to the location area in which the mobile is registered. Thus, a paging request would not be received by the mobile in the distant location area if it is not registered in that location area. Therefore, the mobile should register with a new base station when entering a new location area. Location areas typically include a large group of adjacent cells. It would be inefficient and impractical to instruct all location areas to page the mobile.
  • a mobile may register with one base station in a location area.
  • a location area is typically a group of contiguous cells which do not necessarily have the same area of radio coverage.
  • microcells 20, 30, 40, 50 and 60 may define one location area.
  • a public umbrella cell, public microcell, and a private microcell i.e., a microcell accessible to a closed user group at all times like a home base station or a campus system
  • a mobile may be locked to an appropriate cell based on both information found on an umbrella cell control channel which contains information about the underlying cells and information on each microcell control channel about any overlying cells.
  • information can be broadcast over control channels to the mobiles about the presence of other overlying or underlying cell structures, the attributes of those cell structures and where to find those cell structures.
  • a mobile When selecting the appropriate cell, a mobile can lock on to a candidate control channel and find all the absolute information about the cell associated with that control channel to determine if the cell is appropriate. Alternatively, the mobile can find the same information in the form of relative information by reading messages present on any nearby cells and their control channels.
  • a mobile determines that more than one cell meets minimum requirements, for example signal link quality, access restriction, service profiles, etc.
  • the mobile can scan all or a subset of all control channels and then make the best selection. For example, the mobile may choose to lock on to a cell which does not require an equalizer to be used, or a private cell like a home base station. Typically, small cells do not require an equalizer. Radio propagation and bit rate conditions determine whether an equalizer is needed.
  • Table 1 lists some of the attributes of a cell which may be included in the information on a particular control channel.
  • One cell may have more than one control channel, in which case the absolute and relative information on the several control channels of the cell typically are the same.
  • Some or all information about a control channel can be transmitted on other control channels on cells that are "close” to the control channel of interest.
  • "close” will include contiguous cells which may have the same area of radio coverage.
  • a control channel of microcell 30 may broadcast information concerning cells 10, 20, 40, 50 and 60.
  • the first column represents the type of information about a cell and a control channel which can be broadcast on a control channel.
  • a "Y" in column 2 indicates that the information may be useful if it is about the present control channel to which a mobile is tuned and also may be useful if the information concerns other cells and their respective control channels, absolute and relative information.
  • a "Z” in column 2 indicates the information may be useful if about other cells, relative information.
  • a control channel may be formatted having an "overhead part" and an “other part” as shown in Fig. 3.
  • the overhead part may contain general information about the system like the parameter necessary to be read before a mobile makes an access. Also, the overhead part may contain the information identifying where a particular mobile station will find its paging channel.
  • the "other part” may contain the paging channels and other types of channels.
  • An exemplary control channel organization can be found in U.S. Patent No. 5,081,704 to Umeda et al., entitled “Method of Arranging Radio Control Channels in Mobile Communications".
  • control channel organization information may include information such as where in a particular control channel message that overhead information can be found and where a paging channel may be found.
  • a flag indicating that a respective control channel is time synchronized may be added to the location information of other control channels to aid cell reselection when the mobile is in idle mode.
  • the synchronized information may contain time difference information.
  • Time difference information may be in several forms. The actual time difference between the present control channel and the control channel of another candidate cell may be included on the present control channel. For practical purposes, however, the time difference information may include a single bit of information which indicates whether the time difference is zero.
  • the mobile can rapidly lock to the candidate control channel (cell) assuming information about where to find and decode that control channel is included on the present control channel.
  • the present invention is not limited to TDMA systems and can be applied to other systems including CDMA. Even if only a limited amount of relative information is broadcast on the control channel for capacity reasons, the time difference information makes the cell selection and reselection process faster which improves system performance. For example, the mobile station may be blind for pages a shorter amount of time. Thus, "dead time" associated with receiving pages while searching is reduced.
  • the DS CDMA code is the PN sequence code for communicating with a particular base station.
  • the pilot code is a short code which is used for synchronizing, and provides information about how to find the PN sequence, i.e., the appropriate phasing and start time.
  • Some of the information items which can be placed on a control channel are mutually similar, for example, low mobile station power and maximum mobile transmitter power.
  • Cell selection and reselection criteria may include a path loss criterion parameter which is the difference between the received signal strength and a minimum access threshold signal level.
  • the GSM specification discusses such criteria, but GSM does not employ cell selection and reselection criteria as relative information.
  • the path loss criterion parameter is positive then the cell is of acceptable coverage quality.
  • a second parameter can be used in conjunction with the path loss criterion.
  • the second parameter determines priorities in the reselection of suitable cells and is a combination of the path loss criterion and network controlled parameters.
  • the network parameters control the cell selection for a hierarchical cell structure, for example a microcell and macrocell structure where the network operator wants to assign mobiles to a cell other than the cell from which the mobile receives the strongest signal.
  • the above cell selection and reselection criteria may involve measurement of received signal strengths on respective control channels with absolute or relative parameters sent on the control channels. By comparing the set of measurements and parameters of different control channels, the mobile can select the most appropriate cell. Further, the service profile of a candidate cell may also determine the selection of control channels (cells) . Service profile information might include information such as whether a half rate or full rate speech coder is being used; the data bit transmission rate; and the type of data the cell can handle, i.e., data, voice, and data and voice. To determine the received signal strength of a particular cell, the mobile must go to a control channel of the particular cell in order to measure the received signal strength. Thus, received signal strength is an absolute parameter and cannot be determined relatively.
  • the mobile must make a final check of the received signal strength on the candidate control channel before locking to a control channel.
  • Relative information can be used to screen the control channels and reduce the list of possible suitable control channels.
  • the mobile with some type of relative information determines a group of candidate cells which satisfy a particular criterion. Then, the mobile accesses at least one candidate control channel to find a control channel with an acceptable signal strength.
  • Some parameters associated with signal link requirements may be sent as relative information, but some form of absolute information may be necessary.
  • Control channels often correspond to a cell. However, one cell may have more than one control channel thus the elimination of a control channel as being unsuitable does not necessarily eliminate the cell as a candidate cell.
  • Location area is another parameter which may be broadcast over the control channel. Location areas are constructed to determine where the mobile is located for paging. Typically, a mobile registers with a new base station when it changes location area.
  • a variety of cell type information can be provided on a control channel to aid the mobile to lock to a most appropriate cell. For example, some cells are available for particular situations like cells for emergency calls only; moving cells where the moving entity defines the cell like a plane or bus; test cells which are cells an operator may want to test (e.g., because they are being added to the system) and thus are limited to specific mobiles; a home base station which is assigned and accessible to a closed user group, e.g., members of a particular household; rescue cells which are used when the mobile may immediately need a cell, for example to reestablish a call; barred cells where no call set up is possible because of, for example, imminent cell shut down for maintenance purposes; and other public and private cell types.
  • Cell type information can take the form of cell system information. Exemplary cell systems may include a campus system which may be limited to a certain area and a certain user group, and a city phone system which may have different services, costs, and power requirements.
  • Fig. 4 represents a block diagram of an exemplary cellular mobile radiotelephone system according to one embodiment of the present invention.
  • the system shows an exemplary base station 110 and a mobile 120.
  • the base station includes a control and processing unit 130 which is connected to the MSC 140 which in turn is connected to the public switched telephone network (not shown) .
  • General aspects of such cellular radiotelephone systems are known in the art.
  • An exemplary system can be found in U.S. Patent No.
  • the base station 110 for a cell includes a plurality of voice channels handled by voice channel transceiver 150 which is controlled by the control and processing unit 130. Also, each base station includes a control channel transceiver 160 which may be capable of handling more than one control channel. The control channel transceiver 160 is controlled by the control and processing unit 130. The control channel transceiver 160 broadcasts control information over the control channel of the base station or cell to mobiles locked to that control channel.
  • the mobile 120 When the mobile 120 is in idle mode, it periodically scans the control channels of base stations like base station 110 to determine which cell to lock on or camp to.
  • the mobile 120 receives the absolute and relative information broadcast on a control channel at its voice and control channel transceiver 170.
  • the processing unit 180 evaluates the received control channel information which includes the characteristics of the candidate cells and determines which cell the mobile should lock to.
  • the received control channel information not only includes absolute information concerning the cell with which it is associated, but also contains relative information concerning other cells proximate to the cell with which the control channel is associated.
  • Table 1 The types of information which may be present on the control channel are shown in previously discussed Table 1.

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Dans un système de radiotéléphone (10), le canal de commande de chaque cellule (20-60) peut être configuré afin de diffuser des informations absolues concernant sa cellule et des informations relatives concernant d'autres cellules y compris la caractéristique de la cellule. De plus, l'emplacement des autres canaux de commande peut également être inclus dans les informations diffusées sur un canal de commande d'une cellule particulière. Ces informations sont ensuite utilisées pour verrouiller une unité mobile (120) sur une cellule préférée.
PCT/US1993/008780 1992-09-16 1993-09-16 Procede et appareil de commande de transmission dans un systeme de radiotelephone WO1994007322A1 (fr)

Priority Applications (6)

Application Number Priority Date Filing Date Title
GB9409631A GB2275589B (en) 1992-09-16 1993-09-16 Method and apparatus for communication control in a radiotelephone system
CA002123605A CA2123605C (fr) 1992-09-16 1993-09-16 Methode et appareil de controle des communications pour systeme radiotelephonique
KR1019940701638A KR100277558B1 (ko) 1992-09-16 1993-09-16 무선 전화 시스템의 통신 제어 방법 및 장치
AU49267/93A AU668591B2 (en) 1992-09-16 1993-09-16 Method and apparatus for communication control in a radiotelephone system
SE9401644A SE517898C2 (sv) 1992-09-16 1994-05-11 Förfarande och anordning för kommunikationskontroll i ett radiotelefonsystem
HK98105574A HK1006623A1 (en) 1992-09-16 1998-06-17 Method and apparatus for communication control in a radiotelephone system

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US94546892A 1992-09-16 1992-09-16
US945,468 1992-09-16
US07/955,591 US5353332A (en) 1992-09-16 1992-10-02 Method and apparatus for communication control in a radiotelephone system
US955,591 1992-10-02

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WO1994007322A1 true WO1994007322A1 (fr) 1994-03-31

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CN (1) CN1051901C (fr)
AU (1) AU668591B2 (fr)
CA (1) CA2123605C (fr)
GB (1) GB2275589B (fr)
HK (1) HK1006623A1 (fr)
MX (1) MX9305503A (fr)
MY (1) MY109870A (fr)
NZ (1) NZ256326A (fr)
SE (1) SE517898C2 (fr)
WO (1) WO1994007322A1 (fr)

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WO1999001005A1 (fr) * 1997-06-25 1999-01-07 Nokia Mobile Phones Limited Procede, station de base, station mobile et systeme radio-cellulaire de transfert et de re-selection des cellules
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WO2010049243A1 (fr) * 2008-10-31 2010-05-06 Nokia Siemens Networks Oy Techniques de sélection de cellules pour un mode inactif destinées à des réseaux sans fil
EP2747490A1 (fr) * 2012-12-19 2014-06-25 Koninklijke KPN N.V. Terminaison de session dans un système de télécommunication cellulaire sans fil à efficacité énergétique

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US5987322A (en) * 1997-04-03 1999-11-16 Ericsson Inc. System specified adaptive mobile station behavior within a mobile telecommunications system
WO1998044753A2 (fr) * 1997-04-03 1998-10-08 Ericsson Inc. Comportement adaptatif de stations mobiles specifie par systeme a l'interieur d'un systeme de telecommunications mobile
WO1998044753A3 (fr) * 1997-04-03 1999-01-07 Ericsson Ge Mobile Inc Comportement adaptatif de stations mobiles specifie par systeme a l'interieur d'un systeme de telecommunications mobile
GB2339364A (en) * 1997-04-03 2000-01-19 Ericsson Inc System specified adaptive mobile station behavior within a mobile telecommunications system
US6167283A (en) * 1997-05-06 2000-12-26 Nokia Mobile Phones Ltd. Cell selection based on user profile in cellular radio system
WO1998051102A3 (fr) * 1997-05-06 1999-02-18 Nokia Mobile Phones Ltd Selection de cellule basee sur profil d'usager dans un systeme de radiocommunication cellulaire
WO1998051102A2 (fr) * 1997-05-06 1998-11-12 Nokia Mobile Phones Limited Selection de cellule basee sur profil d'usager dans un systeme de radiocommunication cellulaire
US6510146B1 (en) 1997-06-25 2003-01-21 Nokia Mobile Phones Ltd. Method for handover and cell re-selection
WO1999001005A1 (fr) * 1997-06-25 1999-01-07 Nokia Mobile Phones Limited Procede, station de base, station mobile et systeme radio-cellulaire de transfert et de re-selection des cellules
EP1619870A3 (fr) * 1997-07-22 2008-05-28 O2(Germany) GmbH & Co. OHG Procédé et réseau mobile pour la taxation des appels
EP1619870A2 (fr) 1997-07-22 2006-01-25 Siemens Aktiengesellschaft Procédé et réseau mobile pour la taxation des appels
EP0984644A3 (fr) * 1998-08-31 2000-07-05 Lucent Technologies Inc. Station de base pour une cellule concentrique à portée étendue
US6212405B1 (en) 1998-08-31 2001-04-03 Lucent Technologies Inc. Extended range concentric cell base station
EP0984644A2 (fr) * 1998-08-31 2000-03-08 Lucent Technologies Inc. Station de base pour une cellule concentrique à portée étendue
EP1011286A3 (fr) * 1998-12-18 2001-07-04 Mitsubishi Materials Corporation Dispositif mobile sans fil, appareil de station de base sans fil, et support d'enregistrement
EP1011286A2 (fr) * 1998-12-18 2000-06-21 Mitsubishi Materials Corporation Dispositif mobile sans fil, appareil de station de base sans fil, et support d'enregistrement
WO2008152130A1 (fr) * 2007-06-15 2008-12-18 Nokia Siemens Networks Oy Appareil, procédé et programme informatique fournissant une commande de décodage des informations système
WO2010049243A1 (fr) * 2008-10-31 2010-05-06 Nokia Siemens Networks Oy Techniques de sélection de cellules pour un mode inactif destinées à des réseaux sans fil
EP2747490A1 (fr) * 2012-12-19 2014-06-25 Koninklijke KPN N.V. Terminaison de session dans un système de télécommunication cellulaire sans fil à efficacité énergétique

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HK1006623A1 (en) 1999-03-05
CA2123605C (fr) 2003-11-25
CA2123605A1 (fr) 1994-03-31
AU668591B2 (en) 1996-05-09
SE9401644L (sv) 1994-07-06
CN1051901C (zh) 2000-04-26
GB9409631D0 (en) 1994-07-06
MX9305503A (es) 1994-05-31
SE517898C2 (sv) 2002-07-30
CN1085704A (zh) 1994-04-20
MY109870A (en) 1997-09-30
NZ256326A (en) 1996-05-28
AU4926793A (en) 1994-04-12
GB2275589B (en) 1996-08-28
GB2275589A (en) 1994-08-31

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