WO2003063388A1 - Dispositif et procede permettant d'agir sur la puissance d'emission lors d'une recherche de cellule - Google Patents

Dispositif et procede permettant d'agir sur la puissance d'emission lors d'une recherche de cellule Download PDF

Info

Publication number
WO2003063388A1
WO2003063388A1 PCT/JP2003/000499 JP0300499W WO03063388A1 WO 2003063388 A1 WO2003063388 A1 WO 2003063388A1 JP 0300499 W JP0300499 W JP 0300499W WO 03063388 A1 WO03063388 A1 WO 03063388A1
Authority
WO
WIPO (PCT)
Prior art keywords
transmission power
synchronization channel
base station
power control
determination
Prior art date
Application number
PCT/JP2003/000499
Other languages
English (en)
Japanese (ja)
Inventor
Koichi Aihara
Original Assignee
Matsushita Electric Industrial Co., Ltd.
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 Matsushita Electric Industrial Co., Ltd. filed Critical Matsushita Electric Industrial Co., Ltd.
Publication of WO2003063388A1 publication Critical patent/WO2003063388A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04—TPC
    • H04W52/30—TPC using constraints in the total amount of available transmission power
    • H04W52/32—TPC of broadcast or control channels
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H04B1/7073—Synchronisation aspects
    • H04B1/7083—Cell search, e.g. using a three-step approach
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2201/00—Indexing scheme relating to details of transmission systems not covered by a single group of H04B3/00 - H04B13/00
    • H04B2201/69—Orthogonal indexing scheme relating to spread spectrum techniques in general
    • H04B2201/707—Orthogonal indexing scheme relating to spread spectrum techniques in general relating to direct sequence modulation
    • H04B2201/70702—Intercell-related aspects

Definitions

  • the present invention relates to a transmission power control apparatus and method in cell search of spread spectrum communication, and can be applied to, for example, a transmission power control apparatus and method for controlling transmission power of synchronization channel information.
  • the communication terminal switches the available cells smoothly when the power is turned on or when the cell is switched (soft handover) due to movement. It is necessary to perform a so-called communication cell search.
  • CDMA Code Division Multiple Access
  • a three-stage cell search method is used.
  • slot timing is detected using information of a first synchronization channel (PSCH: Primary Search CHannel).
  • PSCH Primary Search CHannel
  • SSCH Secondary Search CHannel
  • the scrambling code group is identified and the scrambling code timing is detected using the secondary synchronization channel (SSCH: Secondary Search CHannel) information.
  • the scrambling code is identified using the common pilot channel (CPICH: Common Pilot Channel) information and the primary common control physical channel (PCCPCH) information.
  • CPICH Common Pilot Channel
  • PCCPCH primary common control physical channel
  • FIG. 1 is a block diagram showing a schematic configuration of a base station in the conventional spread spectrum communication.
  • the PSCH generation unit 101 is configured to transmit the first synchronization channel information. Generate information.
  • the SSCH generator 102 generates second synchronization channel information.
  • PCCPCH generating section 103 generates primary common control physical channel information that is broadcast information.
  • the CPICH generator 104 generates common pilot channel information.
  • the control channel power adjustment circuit 105 outputs the power information of each control channel to the multiplication circuits 106-6-1 to 106-6-4, respectively. These multiplication circuits control the transmission power for each control channel according to the power information of the control channel power adjustment circuit 105.
  • the addition circuit 107 adds the first synchronization channel information and the second synchronization channel information.
  • the switch 108 switches and outputs primary common control physical channel information and synchronization channel information every time.
  • the adder 109 adds the signal obtained by time-multiplexing the primary common control physical channel information and the synchronization channel information and the common pilot channel information.
  • radio transmission section 110 performs predetermined radio processing on the transmission signal, and transmits the signal to the communication terminal via antenna 111.
  • FIG. 2 shows a channel multiplexing structure of a signal transmitted by a conventional base station.
  • the transmission channels of the synchronization channels (PSCH and SSCH) and channels other than the synchronization channel are fixed for each base station as shown in FIG. For this reason, it may be difficult for a communication terminal with poor propagation path conditions to achieve synchronization.
  • the synchronization channel information must be added. Increasing the key increases the amount of interference with other channels and degrades the characteristics of other channels. Further, if the size of the synchronization channel information is reduced in order to reduce the amount of interference, there is a disadvantage that the detection characteristics of the slot timing of the communication terminal are deteriorated and the synchronization acquisition performance is deteriorated. Disclosure of the invention
  • An object of the present invention is to provide a transmission power control apparatus and method capable of suppressing interference between channels in a cell search at the start of communication or at the time of handover, and enabling a communication terminal to easily acquire synchronization.
  • FIG. 1 is a block diagram showing a schematic configuration of a conventional base station
  • FIG. 2 is a diagram illustrating a channel multiplexing structure of a signal transmitted by a conventional base station.
  • FIG. 3 is a block diagram illustrating a schematic configuration of a base station according to Embodiment 1 of the present invention.
  • FIG. 9 is a diagram showing a channel multiplexing structure of a signal transmitted by the base station according to Embodiment 1.
  • FIG. 5 is a schematic diagram showing an internal configuration of the SCH power adjusting circuit according to Embodiment 1 of the present invention.
  • FIG. 6 is a block diagram showing a schematic configuration of the base station according to Embodiment 2 of the present invention.
  • the gist of the present invention is to adaptively control the transmission power of synchronization channel information in cell search.
  • FIG. 3 is a block diagram showing a schematic configuration of the base station according to Embodiment 1 of the present invention.
  • portions common to FIG. 1 are denoted by the same reference numerals as those in FIG.
  • W-C DMA Wideband CDMA
  • the base station is an asynchronous system. Must be detected.
  • a three-step cell search is performed as one of the means to realize this.
  • the spread code reception timing is narrowed down using the first synchronization channel common to all base stations.
  • the reception timing is determined using the second synchronization channel repeatedly arranged for each base station, and the spread code is further narrowed down. number 3
  • the spread code is determined using a common pilot channel repeatedly arranged for each base station, and as a result, a high-speed cell search is performed.
  • the communication terminal performs a correlation operation on the first synchronization channel information using a matched filter, and detects a peak having a maximum correlation value. Thereby, the temporal reception position of the first synchronization channel is detected.
  • the receiving position is determined from the chip timing in this one slot.
  • slot timings of all channels are detected.
  • the communication terminal detects the frame timing of the channel transmitted by the base station based on the detection result of the slot timing in the first stage. That is, the communication terminal detects the correlation with the received signal in the group of spreading codes (scramble ring code group) constituting the second synchronization channel at the slot timing detected in the first stage, and the correlation value in a certain period of time. Are averaged. The group with the highest average value is identified as the scrambling code group. In the process of detecting the scrambling code group, the frame timing is also detected at the same time.
  • the communication terminal identifies which second synchronization channel it is based on the slot timing detected in the first stage.
  • the second synchronization channel generated by the SSCH generation unit 102 is represented by 256 chip lengths and has 16 types. After the identification of the second synchronization channel, it is specified which scrambling code group the combination of the second synchronization channel of 15 slots constituting one frame corresponds to.
  • the 52 scramble ring codes are grouped into 8 kinds, one group is specified from 64 scramble ring code groups. That is, it is possible to narrow down to eight types of scrambling codes corresponding to one specified group.
  • the communication terminal uses the common pilot channel information to associate with the base station based on the scrambling code group obtained in the second stage. Detect the only corresponding scrambling code.
  • the common pilot channel generated by the CPICH generation unit 104 is a signal transmitted continuously in time without time multiplexing processing, a method using partial correlation for each predetermined chip is used. To find the correlation. Subsequently, the cell search operation is completed by averaging these at regular intervals and identifying the code having the largest average value as the scrambling code of the base station.
  • the SCH and CPICH used in this cell search operation are not completely orthogonal to the desired signal of other communication, the SCH and CPICH cannot be ignored as interference.
  • the transmission power levels of the first synchronization channel and the second synchronization channel are changed according to the transmission switching timing of the common pilot channel transmitted continuously in time. That is, the transmission power levels of the first synchronization channel and the second synchronization channel transmitted by time multiplexing are changed by the SCH power adjustment circuit 202, and the transmission channel of the synchronization channel that interferes with the desired wave of other communication is changed. Is changed over time.
  • Figure 4 shows the signal multiplexing frame structure when the transmission power of the first and second synchronization channels is changed according to the transmission timing of the common pilot channel.
  • FIG. 5 shows the internal configuration of the SCH power adjustment circuit 202.
  • the SCH power adjustment circuit 202 switches the transmission power of the synchronization channel between a low level L0 and a high level L1.
  • the timer 301 measures the transmission switching timing of the common pilot channel, and controls the time for transmitting the SCH with L1 having a large power and the time for transmitting with L0 having a small power level.
  • the power level is not binary, and the transmission power of the first synchronization channel and the second synchronization channel may be controlled stepwise by a plurality of power values.
  • the SCH power adjustment circuit 202 controls the transmission power of the synchronization channel.
  • the multiplication circuit 201 generates a signal obtained by adding the first synchronization channel and the second synchronization channel and a SCH power adjustment circuit. The output value of the path 202 is multiplied.
  • the power of the synchronization channel is changed with time, it is possible to improve the synchronization acquisition performance of the communication terminal while suppressing interference to other channels.
  • the transmission power of the synchronization channel is controlled by a timer owned by the base station, but in the present embodiment, the number of lines on which the base station is performing communication and the communication power existing in the base station area A case will be described in which the number of terminals and the like (hereinafter referred to as determination information) are detected, and the transmission power of the synchronization channel is controlled in accordance with the detection result.
  • FIG. 6 is a block diagram showing a schematic configuration of a base station according to Embodiment 2. 6, the same reference numerals as in FIG. 3 denote the same parts as in FIG. 3, and a detailed description thereof will be omitted.
  • the determination unit 410 performs a threshold determination based on the input determination information, and outputs a determination result to the SCH power adjustment circuit 402.
  • the SCH power adjustment circuit 402 switches the transmission power to a low level or a high level based on the result of the threshold determination output from the determination section 401.
  • the determination information is set as the number of lines used by the base station for communication and the transmission power of the synchronization channel is controlled based on the number.
  • the base station detects the number of communicating lines in another functional unit (not shown), and outputs the detected number of lines to the determining unit 401 as determination information.
  • the determination unit 401 determines a threshold between the input number of lines and a predetermined threshold. If the result of the determination is less than the threshold, a control signal for increasing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to SCH power adjustment circuit 402.
  • the control signal for reducing the transmission power of the synchronization channel to be transmitted to the target communication terminal is S Output to CH power adjustment circuit 402. This is because there are many other communication terminals communicating with the base station, and unless the transmission power of the synchronization channel to be transmitted to the target communication terminal is reduced, the interference to other communication terminals increases.
  • the base station detects the number of communication terminals (including communicating and waiting) in the area of the base station by another functional unit (not shown) and outputs the detected number of terminals to the determination unit 401 as determination information. .
  • the determination unit 401 determines a threshold value between the input number of terminals and a predetermined threshold value. If the result of the determination is less than the threshold, a control signal for increasing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to the SCH power adjustment circuit 402.
  • a control signal for reducing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to the SCH power adjustment circuit 402. This is because considering the other communication terminals communicating with the base station and the waiting communication terminals, unless the transmission power of the synchronization channel to be transmitted to the target communication terminal is reduced, the interference to other channels will be large. Because it becomes.
  • transmission power ratio the ratio of the transmission power of the dedicated channel to the transmission power of the signal transmitted by the base station
  • the signal transmitted by the base station is a signal (including a common channel) transmitted to all communication terminals existing in its own area.
  • An individual channel is data such as a voice signal and a control signal to be transmitted to each communication terminal.
  • the base station calculates the transmission power ratio in another functional unit, not shown, and outputs the obtained transmission power ratio to the determination unit 401 as determination information.
  • the determination unit 401 determines a threshold between the input transmission power ratio and a predetermined threshold. If the result of the determination is less than the threshold, a control signal for increasing the transmission power of the synchronization channel to the target communication terminal is output to the SCH power adjustment circuit 402. This is because even if the transmission power of the synchronization channel is increased, the interference on other channels is not large. On the other hand, if the result of the determination is equal to or greater than the threshold, a control signal for reducing the transmission power of the synchronization channel for the target communication terminal is output to the SCH power adjustment circuit 402. This is because unless the transmission power of the synchronization channel is reduced, the interference on other channels increases.
  • the determination information is the number of channelization codes used by the base station and the transmission power of the synchronization channel is controlled based on the number.
  • Communication terminals need to distinguish not only base stations that are transmitting signals but also channels that are transmitted from the same base station. For example, a base station transmits its own channel to communication terminals, and each communication terminal needs to distinguish its own channel from all other channels that the base station is transmitting.
  • a channelization code which is an orthogonal variable spreading factor (OVSF) code, is used.
  • OVSF orthogonal variable spreading factor
  • a different spreading code is used for each channel transmitted from a base station or a communication terminal.
  • the number of used channelization codes is detected to determine whether or not to interfere with other communication terminals. It can be. That is, by performing a threshold determination between the number of used channelization codes and a predetermined threshold, the transmission channel of the synchronous channel is controlled.
  • the base station detects the number of in-use channelization codes in another functional unit (not shown), and outputs the detected number to the determining unit 401 as determination information.
  • the determination unit 401 determines a threshold value between the number of input channelization codes and a predetermined threshold value. If the result of the determination is less than the threshold, a control signal for increasing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to the SCH power adjustment circuit 402.
  • a control signal for reducing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to SCH power adjustment circuit 402. This is because unless the transmission power of the synchronization channel transmitted to the target communication terminal is reduced, interference with other channels will increase.
  • the transmission information of the synchronization channel is controlled based on the determination information as the total transmission power of the signal transmitted by the base station.
  • the base station detects the total transmission power of the signal transmitted by the base station in another functional unit (not shown), and outputs the detected total transmission power to the determination unit 401 as determination information.
  • the determination unit 401 determines a threshold between the input total transmission power and a predetermined threshold. If the result of the determination is less than the threshold value, a control signal for increasing the transmission power of the synchronization channel to be transmitted to the target communication terminal is output to the SCH power adjustment circuit 402.
  • the synchronization channel for the target communication terminal By controlling the transmission power of the target communication terminal based on the determination information, the target communication terminal can easily acquire synchronization while suppressing the interference given to other channels.
  • the determination information is based on the number of springs used by the base station, the number of communication terminals existing in the base station area, the transmission power ratio, the number of channelization codes used by the base station, and the base station.
  • the transmission power control of the synchronization channel described above is based on the number of communication lines, the number of communication terminals in the base station area, the transmission power ratio,
  • the channelization code As a reference and when using the total transmission power of the signal transmitted by the base station as a reference, the following has been described, but these may be arbitrarily combined.
  • the channel power of PCC PCH may be controlled.
  • the transmission power of a synchronization channel related to synchronization acquisition is adaptively controlled, the synchronization acquisition performance on the reception side is improved while suppressing interference to other channels. Can be done.
  • the present invention relates to a transmission power control apparatus and method for cell search in spread spectrum communication, and is suitable for use in, for example, a transmission power control apparatus and method for controlling transmission power of synchronization channel information.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Synchronisation In Digital Transmission Systems (AREA)

Abstract

Dans le cadre de ce procédé, une unité de production de canal de recherche principal (PSCH) (101) produit une première information de canal de synchronisation tandis qu'une unité de production de canal de recherche auxiliaire (SSCH) (102) produit une seconde information de canal de synchronisation. La puissance d'émission de ces informations est commandée d'après une information relative à la puissance fournie par un circuit de commande de puissance de canal de commande (105). Un circuit de réglage de puissance de canal de recherche (SCH) (202) diminue ou augmente périodiquement la puissance d'émission du canal de synchronisation. Un circuit multiplicateur (201) multiplie un signal, obtenu par l'addition des deux canaux de synchronisation, par une valeur de sortie provenant du circuit de réglage de puissance de canal de recherche (SCH) (202). Il est, de la sorte, possible d'éliminer toute interférence avec d'autres canaux lors d'une recherche de cellule ainsi que d'améliorer les capacités de saisie de synchronisation au niveau du terminal de communications.
PCT/JP2003/000499 2002-01-22 2003-01-22 Dispositif et procede permettant d'agir sur la puissance d'emission lors d'une recherche de cellule WO2003063388A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2002-12982 2002-01-22
JP2002012982A JP2003218788A (ja) 2002-01-22 2002-01-22 セルサーチにおける送信電力制御装置及び方法

Publications (1)

Publication Number Publication Date
WO2003063388A1 true WO2003063388A1 (fr) 2003-07-31

Family

ID=27606058

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2003/000499 WO2003063388A1 (fr) 2002-01-22 2003-01-22 Dispositif et procede permettant d'agir sur la puissance d'emission lors d'une recherche de cellule

Country Status (2)

Country Link
JP (1) JP2003218788A (fr)
WO (1) WO2003063388A1 (fr)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4519606B2 (ja) * 2004-11-05 2010-08-04 株式会社エヌ・ティ・ティ・ドコモ 基地局および移動通信システム並びに送信電力制御方法
JP4463780B2 (ja) * 2005-06-14 2010-05-19 株式会社エヌ・ティ・ティ・ドコモ 送信装置および送信方法
JP2008306293A (ja) * 2007-06-05 2008-12-18 Toshiba Corp アドホックネットワークシステム
US9456328B2 (en) 2011-06-08 2016-09-27 Marvell World Trade Ltd. Method and apparatus for dynamically adjusting a configurable parameter of a discovery protocol during discovery of devices in a wireless network
WO2013005273A1 (fr) * 2011-07-01 2013-01-10 富士通株式会社 Station de base et procédé de commande de puissance

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06276140A (ja) * 1993-03-23 1994-09-30 Oki Electric Ind Co Ltd 基地局回線制御装置
JP2000201101A (ja) * 1999-01-07 2000-07-18 Fujitsu Ltd 拡散通信システムとその移動機
JP2001044929A (ja) * 1999-07-28 2001-02-16 Nec Saitama Ltd 基地局送信装置とそれを用いたｃｄｍａ移動通信システム

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06276140A (ja) * 1993-03-23 1994-09-30 Oki Electric Ind Co Ltd 基地局回線制御装置
JP2000201101A (ja) * 1999-01-07 2000-07-18 Fujitsu Ltd 拡散通信システムとその移動機
JP2001044929A (ja) * 1999-07-28 2001-02-16 Nec Saitama Ltd 基地局送信装置とそれを用いたｃｄｍａ移動通信システム

Also Published As

Publication number Publication date
JP2003218788A (ja) 2003-07-31

Similar Documents

Publication Publication Date Title
US7532590B2 (en) Cell search apparatus and method in a mobile communication system
US6961565B2 (en) Cell search method and apparatus for mobile station in mobile communication system
CA2305873C (fr) Dispositif et procede de gestion de transmissions dans un systeme amcr
EP1048116B1 (fr) Dispositif d'identification de séquence de bruits pseudoaléatoires dans un système de communication à AMCR
KR20100044913A (ko) 비동기 무선 네트워크에서의 통신
EP1419586A2 (fr) Procede et appareil destines a effectuer une recherche de transfert amcr large bande
US6944207B2 (en) CDMA receiver having a searcher intermittently operable
RU2352076C2 (ru) Кадровая синхронизация и идентификация скремблирующего кода в системах беспроводной связи и способы для этого
JP3473575B2 (ja) Ｃｄｍａ移動通信装置及びそれに用いる基地局検出方法
US6944149B1 (en) Apparatus and method or searching for PN sequence phase in multi-carrier CDMA mobile communication system
JP3358170B2 (ja) Ｃｄｍａ無線通信の受信方法
KR100584337B1 (ko) 이동통신 시스템에서 셀 탐색 및 다중경로 탐색 장치 및방법
KR20080090580A (ko) 페이지 감시 방법 및 장치
WO2001026243A1 (fr) Recepteur amcr et methode afferente
JP2002185365A (ja) セルサーチ方法およびセルサーチ装置
CN101103547A (zh) 使用执行扰码确定的瑞克搜索器的小区搜索
WO2003063388A1 (fr) Dispositif et procede permettant d'agir sur la puissance d'emission lors d'une recherche de cellule
JP2001217814A (ja) 通信システム
KR101265633B1 (ko) 이동통신 시스템에서의 채널 신호 탐색 장치 및 방법
JP3835724B2 (ja) 同期方法及び同期回路
US7151766B1 (en) Radio communication apparatus used in CDMA communication system and power consumption control method therefor
JP3778780B2 (ja) 携帯電話機
JPH06197096A (ja) 移動通信システム
JP3150129B2 (ja) Ｃｄｍａ移動体通信受信装置
JP2003188807A (ja) 無線通信装置

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SC SD SE SG SK SL TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase