JP2000023238A - Cell configuration method in mobile communication system, radio access system and mobile set - Google Patents
Cell configuration method in mobile communication system, radio access system and mobile setInfo
- Publication number
- JP2000023238A JP2000023238A JP18740898A JP18740898A JP2000023238A JP 2000023238 A JP2000023238 A JP 2000023238A JP 18740898 A JP18740898 A JP 18740898A JP 18740898 A JP18740898 A JP 18740898A JP 2000023238 A JP2000023238 A JP 2000023238A
- Authority
- JP
- Japan
- Prior art keywords
- base station
- transmission power
- mobile
- cell configuration
- communication
- Prior art date
- Legal status (The legal status 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 status listed.)
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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
- H04W52/18—TPC being performed according to specific parameters
- H04W52/24—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters
- H04W52/243—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters taking into account interferences
- H04W52/244—Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、高速データ通信を
可能とする移動通信システムにおけるセル構成法、無線
アクセス方式及び移動機に関する。The present invention relates to a cell configuration method, a radio access system, and a mobile station in a mobile communication system capable of high-speed data communication.
【０００２】[0002]
【従来の技術】ＣＤＭＡ（Code Division Multiple
Access：符号分割多元接続）等の移動通信システムにお
いて、移動機及び基地局では、送信パワーコントロール
を行うことにより、基地局及び移動局における受信電力
が一定となるように制御している。その結果、チャネル
間干渉を防止し、一定の品質で多数のユーザが使用する
ことが可能となっている。2. Description of the Related Art CDMA (Code Division Multiple)
In a mobile communication system such as Access (code division multiple access) or the like, the mobile station and the base station perform transmission power control to control the received power at the base station and the mobile station to be constant. As a result, it is possible to prevent inter-channel interference and to be used by many users with a certain quality.
【０００３】ところで、移動通信システムでは、通信相
手との距離により送信電力が大き変化する。例えば、自
由空間において、一般に用いられる以下の伝搬損失の式
からも、通信相手との距離により電力損失（ＬＯＳＳ）
が大きく変化することがわかる。 ＬＯＳＳ［ｄＢ］＝１ｏｇ10（４×π×ｄ／λ）2 ・・・・・（１） ここで、ｄは通信相手との距離［ｍ］、λは波長［ｍ］
である。この式において、例えば、移動機が２ＧＨｚ
（λ＝０．１５）の周波数を用いて通信する場合を計算
すると、基地局からの距離が１０ｍの場合には、５８．
５ｄＢ、１００ｍの場合には、７８．５ｄＢ、１ｋｍで
は９８．５ｄＢの損失となる。このため、基地局におけ
る受信電力を一定とするには、移動機は、１０ｍの場合
と比較して、１００ｍでは２０ｄＢ、１ｋｍでは４０ｄ
Ｂ高い送信パワーが必要となる。[0003] In a mobile communication system, the transmission power greatly changes depending on the distance to a communication partner. For example, in the free space, the power loss (LOSS) depends on the distance to the communication partner from the following commonly used equation of propagation loss.
It can be seen that changes greatly. LOSS [dB] = 1 log 10 (4 × π × d / λ) 2 (1) where d is the distance [m] to the communication partner and λ is the wavelength [m].
It is. In this equation, for example, if the mobile device is 2 GHz
When the case where communication is performed using the frequency of (λ = 0.15) is calculated, when the distance from the base station is 10 m, 58.
In the case of 5 dB and 100 m, the loss is 78.5 dB and in the case of 1 km, the loss is 98.5 dB. For this reason, in order to keep the received power at the base station constant, the mobile station needs 20 dB at 100 m and 40 dB at 1 km, as compared with the case of 10 m.
B High transmission power is required.
【０００４】ところで、このようなパワーコントロール
を行う無線通信システムにおいて、高速データ通信を実
現するために、幾つかの方法がある。例えばＴＤＭＡ
（TimeDivision Multiple Access：時分割多元接続）
では、一つのデータを複数のチャネルを用いて送信する
ことにより実現するのが一般的である。また、符号分割
多元接続では、複数のコードにより多重するか、又は、
ｌチャネル当たりの通信速度を上げることにより実現す
ることができる。In a wireless communication system that performs such power control, there are several methods for realizing high-speed data communication. For example, TDMA
(TimeDivision Multiple Access)
Then, it is general to realize by transmitting one data using a plurality of channels. In code division multiple access, multiplexing with a plurality of codes or
This can be realized by increasing the communication speed per 1 channel.
【０００５】[0005]
【発明が解決しようとする課題】従来技術において、高
速データ通信を上記のように、複数チャネル多重、複数
コード多重又はｌチャネル当たりの通信速度を上げるこ
とにより実現する。ところで、ＴＤＭＡにおいて、図１
に示すように、一つのデータに対してＴＤＭＡの複数の
タイムスロットを使用して通信速度を上げた場合は、Ｎ
倍の通信速度を実現するためにはＮ倍の送信電力を必要
とする。つまり、ＴＤＭＡの１フレームに３つのタイム
スロットを有する場合を例にとれば、図１（Ａ）では、
第１番目のタイムスロット＃１のみを用いて通信してい
るのに対し、図１（Ｂ）のように、タイムスロット＃１
〜＃３を使用して通信した場合は、通信速度は３倍にな
るが、そのために電力も３倍必要となる。In the prior art, high-speed data communication is realized by multiplexing a plurality of channels, multiplexing a plurality of codes, or increasing the communication speed per 1 channel, as described above. By the way, in TDMA, FIG.
As shown in (1), when the communication speed is increased by using a plurality of TDMA time slots for one data, N
To realize twice the communication speed, N times transmission power is required. That is, in the case where one frame of TDMA has three time slots as an example, in FIG.
While communication is performed using only the first time slot # 1, as shown in FIG.
When communication is performed using # 3 to # 3, the communication speed is tripled, and therefore, the power is also tripled.
【０００６】また、ＣＤＭＡにおいて、複数のコードを
用いて多重することにより通信速度を上げる場合は、１
コード当たりの必要な送信電力は変わらなくても、複数
のコードを用いれば、それだけ必要な送信電力が大きく
なる。例えば、Ｎコード多重する場合には、送信電力は
Ｎ倍必要となる。さらに、移動通信のように様々な方向
から遅延波が到来するマルチパス環境下においては、コ
ード間の相関が十分でなくなるために、それ以上の送信
電力が必要となる場合がある。[0006] In CDMA, when the communication speed is increased by multiplexing using a plurality of codes, one code is required.
Even if the required transmission power per code does not change, if a plurality of codes are used, the required transmission power increases accordingly. For example, when N codes are multiplexed, the transmission power is required N times. Further, in a multipath environment where delayed waves arrive from various directions, such as in mobile communication, a higher transmission power may be required because the correlation between codes becomes insufficient.
【０００７】また、ＣＤＭＡにおいて、１チャネル当た
りの通信速度を上げることにより通信速度を上げる場合
は、通信速度を上げることにより拡散率が下がる。拡散
率は、信号対雑音の改善の度合いを表しているので、通
信速度を上げた場合、上げる前と同じ品質を得るために
は、送信電力を上げ、そのＳＮ比を改善する必要があ
る。例えば、通信速度をＮ倍にすると、拡散率は１／Ｎ
になり拡散ゲインも１／Ｎとなる。このため、送信電力
はＮ倍必要となる。In CDMA, when the communication speed is increased by increasing the communication speed per channel, the spreading factor is decreased by increasing the communication speed. Since the spreading factor indicates the degree of improvement in signal-to-noise, when the communication speed is increased, it is necessary to increase the transmission power and improve the SN ratio to obtain the same quality as before the increase. For example, if the communication speed is increased by N times, the spreading factor is 1 / N
And the diffusion gain also becomes 1 / N. Therefore, the transmission power is required to be N times.
【０００８】以上の通り、高速データ通信を実現すると
送信電力が増大する。従って、高速データ通信を実現す
ると、増幅器が大型となり、電池の容量を大きくする必
要がある。このために、移動機の小型化が困難となる問
題がある。本発明は、上記間題に鑑みなされたものであ
り、高速データ通信における移動機の小型化を図ること
を目的とするものである。As described above, when high-speed data communication is realized, transmission power increases. Therefore, when high-speed data communication is realized, the size of the amplifier becomes large and the capacity of the battery needs to be increased. For this reason, there is a problem that it is difficult to reduce the size of the mobile device. The present invention has been made in view of the above problems, and has as its object to reduce the size of a mobile device in high-speed data communication.
【０００９】[0009]
【課題を解決するための手段】請求項１に記載された発
明は、移動通信システムにおけるセル構成法において、
送信電力が大きい基地局（基地局Ｂ）で広い通信範囲を
カバーするマクロセル２内に、送信電力が小さい基地局
（基地局Ａ）で狭い通信範囲をカバーする複数のマイク
ロセル１を有し、前記送信電力が大きい基地局の最大通
信可能速度ＢMA X を前記送信電力が小さい基地局の最大
通信可能速度ＡMAX よりも小さくする（ＡMAX ＞
ＢMAX ）ことを特徴とする移動通信システムにおけるセ
ル構成法である。According to a first aspect of the present invention, there is provided a method for configuring a cell in a mobile communication system.
In a macro cell 2 covering a wide communication range with a base station (base station B) having a large transmission power, a plurality of micro cells 1 covering a narrow communication range with a base station (base station A) having a small transmission power are provided. the smaller than the maximum communication speed available a MAX of the transmission power the maximum communication speed available B MA X of the transmission power is large base station is small base station (a MAX>
B MAX ) in a mobile communication system.
【００１０】請求項１記載の発明によれば、同一のエリ
アを送信電力が大きい基地局と送信電力が小さい基地局
でカバーし、送信電力が大きい基地局の最大通信可能速
度を前記送信電力が小さい基地局の最大通信可能速度よ
りも小さくすることにより、高速データ通信における移
動機の小型化を図ることができるゾーン構成とすること
ができる。According to the first aspect of the present invention, the same area is covered by a base station having a large transmission power and a base station having a small transmission power. By making the communication speed smaller than the maximum communicable speed of the small base station, it is possible to provide a zone configuration in which the mobile device in high-speed data communication can be downsized.
【００１１】請求項２に記載された発明は、請求項１の
セル構成法により構成されたセル構成を有する移動通信
システムにおける無線アクセス方式において、移動機の
通信速度Ｕに応じて、移動機が通信する基地局として、
前記送信電力が大きい基地局と前記送信電力が小さい基
地局の内の一方を選択することを特徴とする無線アクセ
ス方式である。According to a second aspect of the present invention, there is provided a radio access system in a mobile communication system having a cell configuration constituted by the cell configuration method according to the first aspect, wherein the mobile unit is adapted to operate in accordance with a communication speed U of the mobile unit. As a communicating base station,
A radio access method characterized in that one of a base station having a large transmission power and a base station having a small transmission power is selected.
【００１２】請求項２記載の発明によれば、移動機の通
信速度が大きい場合、基地局又は移動機は、移動機の送
信電力が小さくて済むように送信電力が小さい基地局を
選択して通信することにより、高速データ通信における
移動機の小型化を図ることができる。請求項３に記載さ
れた発明は、請求項１のセル構成法により構成されたセ
ル構成を有する移動通信システムにおける無線アクセス
方式において、各基地局は、移動機に送信電力を報知
し、該移動機は、報知された送信電力と報知した基地局
からの受信信号の受信電力から、それぞれの基地局との
距離を算出し、最も近い基地局を選択して通信すること
を特徴とする無線アクセス方式である。According to the second aspect of the present invention, when the communication speed of the mobile station is high, the base station or the mobile station selects a base station having a low transmission power so that the transmission power of the mobile station is low. The communication can reduce the size of the mobile device in high-speed data communication. According to a third aspect of the present invention, in the radio access system in the mobile communication system having the cell configuration configured by the cell configuration method according to the first aspect, each base station broadcasts transmission power to a mobile device, and The wireless access device calculates a distance to each base station from the broadcasted transmission power and the broadcasted reception power of the received signal from the base station, and selects and communicates with the nearest base station. It is a method.
【００１３】請求項３記載の発明によれば、移動機は、
報知された送信電力と報知した基地局からの受信信号の
受信電力から、それぞれの基地局との距離を算出し、最
も近い基地局を選択して通信することにより、高速デー
タ通信における移動機の小型化を図ることができる。請
求項４に記載された発明は、請求項１のセル構成法によ
り構成されたセル構成を有する移動通信システムにおけ
る無線アクセス方式において、各基地局は、移動機に送
信電力を報知し、該移動機は、報知された送信電力と報
知した基地局からの受信信号の受信電力から、それぞれ
の基地局へ送信する場合の送信電力を算出し、送信電力
の最も低い基地局を選択して通信することを特徴とする
無線アクセス方式である。According to the third aspect of the present invention, the mobile device includes:
From the reported transmission power and the received power of the received signal from the notified base station, the distance to each base station is calculated, and the closest base station is selected and communicated, so that the The size can be reduced. According to a fourth aspect of the present invention, in the radio access system in a mobile communication system having a cell configuration configured according to the cell configuration method of the first aspect, each base station broadcasts transmission power to a mobile station, and The device calculates the transmission power when transmitting to each base station from the reported transmission power and the received power of the received signal from the reported base station, and selects and communicates with the base station with the lowest transmission power. This is a wireless access method characterized by the following.
【００１４】請求項４記載の発明によれば、移動機は、
報知された送信電力と報知した基地局からの受信信号の
受信電力から、それぞれの基地局へ送信する場合の送信
電力を算出し、送信電力の最も低い基地局を選択して通
信することにより、高速データ通信における移動機の小
型化を図ることができる。請求項５に記載された発明
は、請求項１のセル構成法により構成されたセル構成を
有する移動通信システムにおける移動機において、移動
機の通信速度に応じて、移動機が通信する基地局とし
て、前記送信電力が大きい基地局と前記送信電力が小さ
い基地局の内の一方を選択することを特徴とする移動通
信システムにおける移動機である。According to the fourth aspect of the present invention, the mobile device includes:
From the reported transmission power and the received power of the received signal from the reported base station, calculate the transmission power when transmitting to each base station, and select and communicate with the lowest transmission power base station. The size of the mobile device in high-speed data communication can be reduced. According to a fifth aspect of the present invention, there is provided a mobile station in a mobile communication system having a cell configuration configured by the cell configuration method according to the first aspect, wherein the mobile station communicates according to a communication speed of the mobile station. A mobile station in a mobile communication system, wherein one of the base station having the higher transmission power and the base station having the lower transmission power is selected.
【００１５】請求項６に記載された発明は、請求項１の
セル構成法により構成されたセル構成を有する移動通信
システムにおける移動機において、各基地局から報知さ
れた送信電力と報知した基地局からの受信信号の受信電
力から、それぞれの基地局との距離を算出し、最も近い
基地局を選択して通信することを特徴とする移動通信シ
ステムにおける移動機である。According to a sixth aspect of the present invention, there is provided a mobile station in a mobile communication system having a cell configuration configured by the cell configuration method according to the first aspect, wherein the transmission power notified from each base station and the base station notified. A mobile station in a mobile communication system characterized in that a distance to each base station is calculated from a received power of a received signal from the base station, and a closest base station is selected for communication.
【００１６】請求項７に記載された発明は、請求項１の
セル構成法により構成されたセル構成を有する移動通信
システムにおける移動機において、各基地局から報知さ
れた送信電力と該報知した基地局からの受信信号の受信
電力から、それぞれの基地局へ送信する場合の送信電力
を算出し、送信電力の最も低い基地局を選択して通信す
ることを特徴とする移動通信システムにおける移動機で
ある。According to a seventh aspect of the present invention, there is provided a mobile station in a mobile communication system having a cell configuration configured by the cell configuration method according to the first aspect, wherein the transmission power broadcasted from each base station and the broadcasted base station are transmitted. From the received power of the received signal from the station, the mobile station in the mobile communication system characterized by calculating the transmission power when transmitting to each base station, selecting and communicating with the base station with the lowest transmission power is there.
【００１７】請求項５〜７に記載された発明は、移動通
信システムにおいて、高速データ通信における移動機の
小型化を図ることができるセル構成法及び無線アクセス
方式に適した移動機を規定したものである。According to a fifth aspect of the present invention, in a mobile communication system, a mobile device suitable for a cell access method and a radio access system capable of reducing the size of a mobile device in high-speed data communication is defined. It is.
【００１８】[0018]
【発明の実施の形態】（本発明の基本原理）本発明にお
けるセルは、半径１００ｍ程度の通信エリア（マイクロ
セル）と半径２〜３ｋｍ程度の通信エリア（マクロセ
ル）が同一エリアをカバーするように構成されている。DESCRIPTION OF THE PREFERRED EMBODIMENTS (Basic Principle of the Present Invention) In the present invention, a cell has a communication area (micro cell) having a radius of about 100 m and a communication area (macro cell) having a radius of about 2 to 3 km so as to cover the same area. It is configured.
【００１９】一般に、マクロセルは、マイクロセルに比
べ通信中のチャネル切り替えの回数が少なくてすむため
に、高速移動中の通信に適している。また、マイクロセ
ルは、移動機が、移動機に最も近い基地局と通信できれ
ば、送信パワーは少なくて済み、高速データ通信に適し
ている。本発明では、同一エリアにマクロセルとマイク
ロセルを設け、高速データ通信には、マイクロセルを用
いて通信を行い、高速データ通信における移動機の小型
化を図る。 （実施例）図２に、本実施例で用いるセル構成の例を示
す。同一のエリアを送信電力が高く通信範囲の広いマク
ロセル２と、送信電力が低く通信範囲が狭いマイクロセ
ル１の２つ以上のセルでカバーしている。各マイクロセ
ル及びマクロセルには、それぞれ基地局を有し、各基地
局は、基地局識別信号及び基地局の送信電力値を移動機
に向けて報知することができる。ここで、マイクロセル
１とマクロセル２は同一のシステムで同一の周波数であ
る場合だけでなく、異なるシステム、あるいは、異なる
周波数の場合でも良い。In general, a macro cell is suitable for communication during high-speed movement, since the number of times of channel switching during communication is smaller than that of a micro cell. Further, the microcell requires only a small transmission power if the mobile device can communicate with the base station closest to the mobile device, and is suitable for high-speed data communication. In the present invention, a macro cell and a micro cell are provided in the same area, communication is performed using a micro cell for high-speed data communication, and the mobile device in high-speed data communication is reduced in size. (Embodiment) FIG. 2 shows an example of a cell configuration used in this embodiment. The same area is covered by two or more cells, a macro cell 2 having a high transmission power and a wide communication range, and a micro cell 1 having a low transmission power and a narrow communication range. Each microcell and macrocell has a base station, and each base station can broadcast a base station identification signal and a transmission power value of the base station to a mobile station. Here, the micro cell 1 and the macro cell 2 may be used not only for the same system but at the same frequency, but also for different systems or different frequencies.
【００２０】また、マイクロセル１は、マクロセル２に
全てがカバーされることなく、隣接するマクロセル２に
跨って設けても良い。また、隣接するマイクロセル１及
び隣接するマクロセル２は、それぞれ、一部重なってい
ても良い。さらに、セル間に空きが存在しても良い。ま
た、図３に、移動機（端末Ａ）と基地局の位置関係を示
す。マイクロセル１の基地局Ａ（基地局Ａの通信範囲：
マイクロセル）とマクロセル２の基地局Ｂ（基地局Ｂの
通信範囲：マクロセル）が示されている。端末Ａと基地
局Ａとの距離をｒＡ、端末Ａと基地局Ｂとの距離をｒＢ
（＞ｒＡ）とする。The microcell 1 may be provided over an adjacent macrocell 2 without being entirely covered by the macrocell 2. In addition, the adjacent micro cell 1 and the adjacent macro cell 2 may partially overlap each other. Furthermore, there may be a space between cells. FIG. 3 shows the positional relationship between the mobile station (terminal A) and the base station. Base station A of micro cell 1 (communication range of base station A:
A microcell) and a base station B of the macrocell 2 (communication range of the base station B: macrocell) are shown. The distance between terminal A and base station A is rA, and the distance between terminal A and base station B is rB.
(> RA).
【００２１】この通信範囲の異なる複数の基地局で同一
エリアをカバーするシステムにおいて、端末Ａが、通信
範囲の広い基地局Ｂと通信を行う場合には、基地局Ｂと
の距離ｒＢ（＞ｒＡ）に相当する伝搬損失が生じること
から送信電力を大きくする必要性がある。これに対し
て、通信範囲の狭い基地局Ａと通信を行う場合には、基
地局Ａとの距離ｒＡ（＞ｒＢ）に相当する伝搬損失が生
じることから、基地局Ｂと通信する場合に比べて低い送
信電力での通信が可能となる。In a system in which a plurality of base stations having different communication ranges cover the same area, when terminal A communicates with base station B having a wide communication range, distance rB (> rA) to base station B The transmission power needs to be increased because a propagation loss corresponding to ()) occurs. On the other hand, when performing communication with the base station A having a narrow communication range, a propagation loss corresponding to the distance rA (> rB) from the base station A occurs. Communication with low transmission power is possible.
【００２２】従って、高速データ通信を行う場合、移動
機の負担は、基地局Ａと通信する方が基地局Ｂと通信す
るより小さい。そこで、本発明では、通信範囲の広い基
地局Ｂと通信範囲の狭い基地局Ａの最大通信速度を、 基地局Ａの最大通信速度＞基地局Ｂの最大通信速度 と定める。これにより、移動機は、高速データ通信に伴
う送信電力のパワーアップを考慮し、基地局Ｂの最大通
信速度以上の高速データ通信を行う場合には、基地局Ｂ
でなく、基地局Ａと通信を行うことととし、移動局にお
ける負担を軽減し、必要な送信電力の低減を実現する。 （基地局選択１）移動機が、送信電力が大きい基地局と
送信電力が小さい基地局の内の一方を選択する方法の一
例を説明する。Therefore, when performing high-speed data communication, the burden on the mobile station is smaller when communicating with the base station A than when communicating with the base station B. Therefore, in the present invention, the maximum communication speed of the base station B having a wide communication range and the base station A having a narrow communication range is determined as: maximum communication speed of the base station A> maximum communication speed of the base station B. Accordingly, the mobile station considers power-up of transmission power accompanying high-speed data communication, and performs high-speed data communication at a speed equal to or higher than the maximum communication speed of base station B.
Instead, the communication with the base station A is performed, so that the burden on the mobile station is reduced and the required transmission power is reduced. (Base Station Selection 1) An example of a method in which a mobile station selects one of a base station with high transmission power and a base station with low transmission power will be described.
【００２３】移動機の通信速度に応じ、移動機が通信す
る基地局として、送信電力が大きい基地局と送信電力が
小さい基地局の内の一方を選択する。図４に、移動機
（端末Ａ）における基地局選択動作のフローを示す。こ
こでは、基地局Ａの最大通信速度をＡMAX 、基地局Ｂの
最大通信速度をＢMAX （ＡMAX＞ＢMAX ）とする。ま
た、移動機が、通信速度Ｕで通信を開始する場合につい
て説明する。According to the communication speed of the mobile station, one of a base station having a high transmission power and a base station having a low transmission power is selected as a base station with which the mobile station communicates. FIG. 4 shows a flow of a base station selecting operation in the mobile station (terminal A). Here, it is assumed that the maximum communication speed of the base station A is A MAX , and the maximum communication speed of the base station B is B MAX (A MAX > B MAX ). The case where the mobile device starts communication at the communication speed U will be described.
【００２４】移動機から、通信速度Ｕで発信要求があっ
た場合１０に、まず、通信速度ＵがＢMAX よりも大きい
かどうかを比較する１１。通信速度Ｕの方が大きい場合
には、基地局Ａ（マイクロセル）との通信を選択する１
２。一方、通信速度ＵがＢMA X よりも小さい場合には、
基地局Ｂ（マクロセル）との通信を選択する１３。この
選択は、移動機内又はいずれかの基地局で行うことがで
きる。また、通信速度ＵとＢMAX とを比較して選択した
が、移動機の通信速度Ｕと比較する速度は、基地局Ｂの
最大通信速度をＢMAX に限らず、状況に応じ任意に設定
することができる。 （基地局選択２）上記したように、伝送距離が長ければ
それだけ伝送損失が大きくなる。従って、移動通信シス
テムにおいては、移動機と基地局間の距離に応じて、移
動機の送信電力を制御している。移動機と基地局間の距
離が大きければ、大きな送信電力が必要であり、移動機
と基地局間の距離が小さければ、小さな送信電力で済
む。[0024] from the mobile station, the 10 when there is a calling request at a communication speed U, first, 11 the communication speed U is compared whether greater than B MAX. If the communication speed U is higher, the communication with the base station A (micro cell) is selected.
2. On the other hand, if the communication speed U is smaller than B MA X is
Select communication 13 with base station B (macro cell). This selection can be made in the mobile station or at any base station. Although selected by comparing the communication speed U and B MAX, the speed to be compared with the communication speed U of the mobile device is not limited to the maximum communication speed of the base station B to B MAX, is set arbitrarily according to circumstances be able to. (Base station selection 2) As described above, the longer the transmission distance, the greater the transmission loss. Therefore, in the mobile communication system, the transmission power of the mobile device is controlled according to the distance between the mobile device and the base station. If the distance between the mobile station and the base station is large, large transmission power is required, and if the distance between the mobile station and the base station is small, small transmission power is sufficient.
【００２５】移動機が、送信電力の増加を伴う高速デー
タ通信を行う場合、移動機の負担は、移動機と基地局間
の距離が小さい基地局の方が、移動機と基地局間の距離
が大きい基地局と通信するよりも小さい。そこで、移動
機は、高速データ通信を行う場合には、移動機と基地局
間の距離が小さい基地局を選択して通信を行うこととと
し、移動局における負担を軽減し、必要な送信電力の低
減を実現する。When a mobile station performs high-speed data communication with an increase in transmission power, the burden on the mobile station is such that a base station having a small distance between the mobile station and the base station has a greater distance between the mobile station and the base station. Is smaller than communicating with a larger base station. Therefore, when performing high-speed data communication, the mobile station selects a base station having a small distance between the mobile station and the base station to perform communication, thereby reducing the load on the mobile station and reducing the required transmission power. To achieve a reduction.
【００２６】図５に本実施例での移動局における基地局
選択部の構成例を示す。移動機における基地局選択部
は、送信電力検出部２０、受信電力検出部２１、距離算
出部２２及び通信基地局選択信号発生部２３より構成さ
れている。送信電力検出部２０は、基地局からの基地局
識別信号及び送信電力値の報知信号から、基地局の送信
電力（Ｘｄｂ）を検出する。受信電力検出部２１は、該
報知信号の受信信号から、基地局から送信された信号の
受信電力（Ｙｄｂ）を検出する。距離算出部２２は、送
信電力（Ｘｄｂ）と受信電力（Ｙｄｂ）から、基地局間
の伝送損失（Ｘ−Ｙｄｂ）を算出する。FIG. 5 shows an example of the configuration of the base station selector in the mobile station according to the present embodiment. The base station selection unit in the mobile device includes a transmission power detection unit 20, a reception power detection unit 21, a distance calculation unit 22, and a communication base station selection signal generation unit 23. The transmission power detection unit 20 detects the transmission power (Xdb) of the base station from the base station identification signal from the base station and the transmission power value notification signal. The received power detection unit 21 detects the received power (Ydb) of the signal transmitted from the base station from the received signal of the broadcast signal. The distance calculator 22 calculates a transmission loss (X-Ydb) between the base stations from the transmission power (Xdb) and the reception power (Ydb).
【００２７】式（１）は、次のように変形することがで
きる。 ｄ［ｍ］＝１０LOSS/2×λ／（４π）・・・・・・・・（２） そこで、この伝送損失（Ｘ−Ｙｄｂ）を式（２）に代入
して、移動機と基地局間の距離距離ｄ［ｍ］を算出す
る。この距離の算出は、受信された基地局全てに対して
行う。通信基地局選択信号発生部２３は、距離算出部２
２で算出された基地局間の距離ｄの中で、最も小さい距
離の基地局を示す信号を出力する。移動機内の通信制御
部（図示せず）は、この信号を受けて、アンテナの方
向、周波数の切替等を行い、基地局を選択する。Equation (1) can be modified as follows. d [m] = 10 LOSS / 2 × λ / (4π) (2) Then, the transmission loss (X−Ydb) is substituted into the equation (2) to obtain the mobile station and the base station. The distance d [m] between the stations is calculated. The calculation of this distance is performed for all the received base stations. The communication base station selection signal generation unit 23 includes the distance calculation unit 2
A signal indicating the base station having the smallest distance among the distances d between the base stations calculated in 2 is output. Upon receiving this signal, a communication control unit (not shown) in the mobile device switches the direction of the antenna, switches the frequency, and selects a base station.
【００２８】上記の通り、送信電力と受信電力の差が、
基地局までの距離に相当することから、複雑な計算を行
わずに算出できる。また、通信相手の基地局までの距離
を算出することにより、最適な通信相手の基地局を選択
し、移動局の送信電力は低減できる。 （基地局選択３）上記基地局選択２においては、基地局
間の伝送損失（Ｘ−Ｙｄｂ）を算出し、これを式（１）
に代入し、移動機と基地局間の距離ｄ［ｍ］を算出し
た。この距離ｄと基地局に割り当てられた周波数を用い
て、それぞれの基地局へ送信する場合の送信電力を算出
し、送信電力の最も低い基地局を選択してもよい。As described above, the difference between the transmission power and the reception power is
Since it corresponds to the distance to the base station, it can be calculated without performing complicated calculations. Further, by calculating the distance to the communication partner base station, the optimum communication partner base station is selected, and the transmission power of the mobile station can be reduced. (Base Station Selection 3) In the base station selection 2, the transmission loss (X-Ydb) between the base stations is calculated, and this is calculated by the equation (1).
To calculate the distance d [m] between the mobile station and the base station. Using this distance d and the frequency assigned to the base station, the transmission power for transmission to each base station may be calculated, and the base station with the lowest transmission power may be selected.
【００２９】図６に本実施例での移動局における基地局
選択部の構成例を示す。移動機における基地局選択部
は、送信電力検出部３０、受信電力検出部３１、送信電
力算出部３２及び通信基地局選択信号発生部３３より構
成されている。送信電力検出部３０は、基地局からの基
地局識別信号及び送信電力値の報知信号から、基地局の
送信電力（Ｘｄｂ）を検出する。受信電力検出部３１
は、該報知信号の受信信号から、基地局から送信された
信号の受信電力（Ｙｄｂ）を検出する。送信電力算出部
３２は、送信電力（Ｘｄｂ）と受信電力（Ｙｄｂ）か
ら、基地局間の伝送損失（Ｘ−Ｙｄｂ）を算出する。こ
れを式（１）に代入し、移動機と基地局間の距離ｄ
［ｍ］を算出し、更に、必要な送信電力を算出する。こ
の送信電力の算出は、受信された基地局全てに対して行
う。通信基地局選択信号発生部３３は、送信電力算出部
３２で算出された送信電力の中で、最も小さい送信電力
の基地局を示す信号を出力する。FIG. 6 shows a configuration example of the base station selection unit in the mobile station according to the present embodiment. The base station selection unit in the mobile device includes a transmission power detection unit 30, a reception power detection unit 31, a transmission power calculation unit 32, and a communication base station selection signal generation unit 33. The transmission power detection unit 30 detects the transmission power (Xdb) of the base station from the base station identification signal from the base station and the transmission power value notification signal. Received power detector 31
Detects the received power (Ydb) of the signal transmitted from the base station from the received signal of the broadcast signal. The transmission power calculator 32 calculates a transmission loss (X-Ydb) between the base stations from the transmission power (Xdb) and the reception power (Ydb). Substituting this into equation (1) gives the distance d between the mobile station and the base station.
[M] is calculated, and further, required transmission power is calculated. The calculation of the transmission power is performed for all the received base stations. The communication base station selection signal generator 33 outputs a signal indicating the base station having the smallest transmission power among the transmission powers calculated by the transmission power calculator 32.
【００３０】また、必要な送信電力を算出することによ
り、移動機は移動機自体が送信可能な最大送信可能電力
と比較することが可能となり、必要な送信電力が、最大
送信可能電力を越えている場合には、通信速度を下げる
制御が可能となる。上記のとおり、本実施例によれば、
高速データ通信を行う際には、最適なマイクロセル基地
局と通信を行うことにより、移動機の送信電力が低減で
き、移動機の電池寿命を長くすることが可能となるばか
りでなく、移動機の小型化が可能となる。Further, by calculating the required transmission power, the mobile station can compare the maximum transmission power that can be transmitted by the mobile station itself, and the required transmission power exceeds the maximum transmission power. If so, control to reduce the communication speed becomes possible. As described above, according to the present embodiment,
When performing high-speed data communication, by communicating with the optimal microcell base station, the transmission power of the mobile device can be reduced and the battery life of the mobile device can be prolonged. Can be reduced in size.
【００３１】なお、基地局の選択は、基地局Ａと基地局
Ｂ間の選択であっても良いし、周辺の基地局Ａを含めた
選択であっても良い。The selection of the base station may be a selection between the base station A and the base station B, or may be a selection including the surrounding base stations A.
【００３２】[0032]
【発明の効果】上述の如く本発明によれば、次に述べる
種々の効果を実現することができる。請求項１記載の発
明によれば、同一のエリアを送信電力が大きい基地局と
送信電力が小さい基地局でカバーし、送信電力が大きい
基地局の最大通信可能速度を前記送信電力が小さい基地
局の最大通信可能速度よりも小さくすることにより、高
速データ通信における移動機の小型化を図ることができ
るゾーン構成とすることができる。According to the present invention as described above, the following various effects can be realized. According to the first aspect of the present invention, the same area is covered by a base station having a large transmission power and a base station having a small transmission power, and the maximum communicable speed of the base station having a large transmission power is reduced by the base station having a small transmission power. By making the maximum communication speed lower than the maximum communicable speed, it is possible to provide a zone configuration in which the size of the mobile device in high-speed data communication can be reduced.
【００３３】請求項２記載の発明によれば、移動機の通
信速度が大きい場合、移動機の送信電力が小さくて済む
ように送信電力が小さい基地局を選択して通信すること
により、高速データ通信における移動機の小型化を図る
ことができる。請求項３記載の発明によれば、移動機
は、報知された送信電力と報知した基地局からの受信信
号の受信電力から、それぞれの基地局との距離を算出
し、最も近い基地局を選択して通信することにより、高
速データ通信における移動機の小型化を図ることができ
る。According to the second aspect of the present invention, when the communication speed of the mobile station is high, the base station having a low transmission power is selected and communicated so that the transmission power of the mobile station can be low. It is possible to reduce the size of a mobile device in communication. According to the third aspect of the present invention, the mobile device calculates the distance to each base station from the broadcasted transmission power and the broadcasted reception power of the received signal from the base station, and selects the closest base station. By performing communication, the size of the mobile device in high-speed data communication can be reduced.
【００３４】請求項４記載の発明によれば、移動機は、
報知された送信電力と報知した基地局からの受信信号の
受信電力から、それぞれの基地局へ送信する場合の送信
電力を算出し、送信電力の低い基地局を選択して通信す
ることにより、高速データ通信における移動機の小型化
を図ることができる。基地局毎に異なる周波数を用いる
ために、周波数を考慮した最適な基地局を選択すること
ができる。According to the fourth aspect of the present invention, the mobile device comprises:
From the reported transmission power and the received power of the received signal from the reported base station, the transmission power when transmitting to each base station is calculated, and the base station with the lower transmission power is selected and communicated, thereby achieving high-speed communication. The size of the mobile device in data communication can be reduced. Since a different frequency is used for each base station, an optimal base station can be selected in consideration of the frequency.
【００３５】請求項５〜７に記載された発明によれば、
移動通信システムにおける高速データ通信における小型
化が可能なセル構成法及び無線アクセス方式に適した移
動機を提供することができる。According to the invention described in claims 5 to 7,
It is possible to provide a mobile device suitable for a cell configuration method and a radio access method that can be downsized in high-speed data communication in a mobile communication system.
【図面の簡単な説明】[Brief description of the drawings]
【図１】時分割多元接続方式における高速データ通信を
行う場合のタイムスロットの割当てを示す図。FIG. 1 is a diagram showing time slot allocation when performing high-speed data communication in a time division multiple access system.
【図２】本発明で用いるセルの構成例を示す図。FIG. 2 is a diagram showing a configuration example of a cell used in the present invention.
【図３】本発明で用いるセル構成例における基地局と移
動局の位置関係を示す図。FIG. 3 is a diagram showing a positional relationship between a base station and a mobile station in a cell configuration example used in the present invention.
【図４】本発明で用いる通信開始時の移動局における制
御の流れを示す図。FIG. 4 is a diagram showing a control flow in a mobile station at the start of communication used in the present invention.
【図５】本発明で用いる基地局選択部（その１）の構成
例を示す図。FIG. 5 is a diagram showing a configuration example of a base station selection unit (part 1) used in the present invention.
【図６】本発明で用いる基地局選択部（その２）の構成
例を示す図。FIG. 6 is a diagram showing a configuration example of a base station selection unit (part 2) used in the present invention.
１ マイクロセル ２ マクロセル ２０、３０ 送信電力検出部 ２１、２１ 受信電力検出部 ２２ 距離算出部 ２３、３３ 通信基地局選択部 ３２ 送信電力算出部 基地局Ａ マイクロセルの基地局 基地局Ｂ マクロセルの基地局 DESCRIPTION OF SYMBOLS 1 Microcell 2 Macrocell 20, 30 Transmission power detection part 21, 21 Reception power detection part 22 Distance calculation part 23, 33 Communication base station selection part 32 Transmission power calculation part Base station A Base station of microcell Base station B Base of macrocell Station
Claims (7)
おいて、 送信電力が大きい基地局で広い通信範囲をカバーするマ
クロセル内に、送信電力が小さい基地局で狭い通信範囲
をカバーする複数のマイクロセルを有し、 前記送信電力が大きい基地局の最大通信可能速度を前記
送信電力が小さい基地局の最大通信可能速度よりも小さ
くすることを特徴とする移動通信システムにおけるセル
構成法。In a cell configuration method in a mobile communication system, a plurality of microcells covering a narrow communication range with a base station having a low transmission power are included in a macrocell covering a wide communication range with a base station having a high transmission power. A cell configuration method in a mobile communication system, wherein a maximum communicable speed of a base station having a large transmission power is smaller than a maximum communicable speed of a base station having a small transmission power.
セル構成を有する移動通信システムにおける無線アクセ
ス方式において、 移動機の通信速度に応じて、移動機が通信する基地局と
して、前記送信電力が大きい基地局と前記送信電力が小
さい基地局の内の一方を選択することを特徴とする無線
アクセス方式。2. A radio access system in a mobile communication system having a cell configuration configured according to the cell configuration method according to claim 1, wherein the transmission power is set as a base station with which the mobile device communicates according to a communication speed of the mobile device. Wireless base station which selects one of a base station having a higher transmission power and a base station having a lower transmission power.
セル構成を有する移動通信システムにおける無線アクセ
ス方式において、 各基地局は、移動機に送信電力を報知し、 該移動機は、報知された送信電力と報知した基地局から
の受信信号の受信電力から、それぞれの基地局との距離
を算出し、最も近い基地局を選択して通信することを特
徴とする無線アクセス方式。3. A radio access system in a mobile communication system having a cell configuration configured by the cell configuration method according to claim 1, wherein each base station broadcasts transmission power to a mobile station, and the mobile station broadcasts the transmission power. A wireless access method, wherein a distance to each base station is calculated from the transmitted power and the received power of a received signal from the notified base station, and the closest base station is selected for communication.
セル構成を有する移動通信システムにおける無線アクセ
ス方式において、 各基地局は、移動機に送信電力を報知し、 該移動機は、報知された送信電力と報知した基地局から
の受信信号の受信電力から、それぞれの基地局へ送信す
る場合の送信電力を算出し、送信電力の最も低い基地局
を選択して通信することを特徴とする無線アクセス方
式。4. A radio access system in a mobile communication system having a cell configuration configured by the cell configuration method according to claim 1, wherein each base station broadcasts transmission power to a mobile station, and the mobile station broadcasts the transmission power. The transmission power when transmitting to each base station is calculated from the received transmission power and the received power of the received signal from the notified base station, and the base station having the lowest transmission power is selected for communication. Wireless access method.
セル構成を有する移動通信システムにおける移動機にお
いて、 移動機の通信速度に応じて、移動機が通信する基地局と
して、前記送信電力が大きい基地局と前記送信電力が小
さい基地局の内の一方を選択することを特徴とする移動
通信システムにおける移動機。5. A mobile station in a mobile communication system having a cell configuration configured by the cell configuration method according to claim 1, wherein the transmission power is set as a base station with which the mobile station communicates according to a communication speed of the mobile station. A mobile station in a mobile communication system, wherein one of a large base station and a base station with a small transmission power is selected.
セル構成を有する移動通信システムにおける移動機にお
いて、 各基地局から報知された送信電力と報知した基地局から
の受信信号の受信電力から、それぞれの基地局との距離
を算出し、最も近い基地局を選択して通信することを特
徴とする移動通信システムにおける移動機。6. A mobile station in a mobile communication system having a cell configuration configured according to the cell configuration method according to claim 1, wherein a transmission power reported from each base station and a reception power of a received signal from the reported base station are used. A mobile station in a mobile communication system, which calculates a distance from each base station and selects the closest base station for communication.
セル構成を有する移動通信システムにおける移動機にお
いて、 各基地局から報知された送信電力と該報知した基地局か
らの受信信号の受信電力から、それぞれの基地局へ送信
する場合の送信電力を算出し、送信電力の最も低い基地
局を選択して通信することを特徴とする移動通信システ
ムにおける移動機。7. A mobile station in a mobile communication system having a cell configuration configured by the cell configuration method according to claim 1, wherein a transmission power broadcast from each base station and a reception power of a received signal from the broadcasted base station. A mobile station in a mobile communication system, wherein the mobile station calculates transmission power when transmitting to each base station, and selects and communicates with a base station having the lowest transmission power.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18740898A JP2000023238A (en) | 1998-07-02 | 1998-07-02 | Cell configuration method in mobile communication system, radio access system and mobile set |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18740898A JP2000023238A (en) | 1998-07-02 | 1998-07-02 | Cell configuration method in mobile communication system, radio access system and mobile set |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000023238A true JP2000023238A (en) | 2000-01-21 |
Family
ID=16205521
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18740898A Pending JP2000023238A (en) | 1998-07-02 | 1998-07-02 | Cell configuration method in mobile communication system, radio access system and mobile set |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000023238A (en) |
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|---|---|---|---|---|
| JP2007101261A (en) * | 2005-09-30 | 2007-04-19 | Seiko Precision Inc | Existence range identifying system, existence range identifying method, and program |
| JP2008011452A (en) * | 2006-06-30 | 2008-01-17 | Matsushita Electric Ind Co Ltd | Communication terminal device and communication method |
| WO2009122778A1 (en) * | 2008-03-31 | 2009-10-08 | 日本電気株式会社 | Radio station device, radio resource control method, recording medium containing radio station control program, and radio communication system |
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-
1998
- 1998-07-02 JP JP18740898A patent/JP2000023238A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007101261A (en) * | 2005-09-30 | 2007-04-19 | Seiko Precision Inc | Existence range identifying system, existence range identifying method, and program |
| JP4744377B2 (en) * | 2006-06-30 | 2011-08-10 | パナソニック株式会社 | Communication terminal device and communication method |
| JP2008011452A (en) * | 2006-06-30 | 2008-01-17 | Matsushita Electric Ind Co Ltd | Communication terminal device and communication method |
| JP5440494B2 (en) * | 2008-03-31 | 2014-03-12 | 日本電気株式会社 | Base station apparatus, radio resource control method, radio station control program, and radio communication system |
| JPWO2009122778A1 (en) * | 2008-03-31 | 2011-07-28 | 日本電気株式会社 | Base station apparatus, radio resource control method, radio station control program, and radio communication system |
| CN101965740B (en) * | 2008-03-31 | 2013-09-04 | 日本电气株式会社 | Radio station device, radio resource control method, recording medium containing radio station control program, and radio communication system |
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| JP2010187138A (en) * | 2009-02-10 | 2010-08-26 | Kddi Corp | Mobile station, communication method, and communication program |
| JP2011041250A (en) * | 2009-08-18 | 2011-02-24 | Seyoung Information & Telecommunication Co Ltd | Simultaneous interpretation system for bidirectional audio data communication based on binary code division multiple accesses |
| WO2018167841A1 (en) * | 2017-03-14 | 2018-09-20 | 富士通株式会社 | Communication apparatus, communication system and communication method |
| JPWO2018167841A1 (en) * | 2017-03-14 | 2020-01-23 | 富士通株式会社 | Communication device, communication system, and communication method |
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