JP3080205B2 - Channel switching method during communication of spread spectrum mobile communication - Google Patents
Channel switching method during communication of spread spectrum mobile communicationInfo
- Publication number
- JP3080205B2 JP3080205B2 JP05110545A JP11054593A JP3080205B2 JP 3080205 B2 JP3080205 B2 JP 3080205B2 JP 05110545 A JP05110545 A JP 05110545A JP 11054593 A JP11054593 A JP 11054593A JP 3080205 B2 JP3080205 B2 JP 3080205B2
- Authority
- JP
- Japan
- Prior art keywords
- radio
- zone
- frequency
- communication
- channel
- 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.)
- Expired - Fee Related
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/0005—Control or signalling for completing the hand-off
- H04W36/0083—Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
- H04W36/0085—Hand-off measurements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W36/00—Hand-off or reselection arrangements
- H04W36/06—Reselecting a communication resource in the serving access point
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W72/00—Local resource management
- H04W72/04—Wireless resource allocation
- H04W72/044—Wireless resource allocation based on the type of the allocated resource
- H04W72/0453—Resources in frequency domain, e.g. a carrier in FDMA
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
Description
【０００１】[0001]
【産業上の利用分野】この発明はスペクトラム拡散方式
を用いたセルラ移動通信方式における通信中チャネル切
替方法に関するものである。[Field of the Invention The present invention is relates to the communication of channel switching how in a cellular mobile communication system using a spread spectrum system.
【０００２】[0002]
【従来の技術】セルラ移動通信方式は現在デジタル自動
車電話方式として実用化されている。即ち、デジタル自
動車電話方式においては図２Ａに示すようにサービスエ
リア１が複数の無線ゾーン２ａ，２ｂ，２ｃ…に分割さ
れ、これら各無線ゾーン２ａ，２ｂ，２ｃ…にゾーン毎
に個別周波数の制御チャネル３ａ，３ｂ，３ｃ…がそれ
ぞれ割当てられ、各無線ゾーン２ａ，２ｂ，２ｃ…にそ
れぞれ設置された無線基地局４ａ，４ｂ，４ｃ…からそ
れぞれ制御チャネル３ａ，３ｂ，３ｃ…が送信されてい
る。移動機は通信中チャネル切替を行う際、図２Ｂに示
すようにＴＤＭＡの空きスロットＩを利用して前記無線
ゾーン毎に設けられている個別周波数の制御チャネル３
ａ，３ｂ，３ｃ…の受信レベルを順次測定し、それらの
受信レベルを比較して切替先無線ゾーンを決定すること
により通信中チャネル切替を行っている。2. Description of the Related Art The cellular mobile communication system is currently in practical use as a digital car telephone system. That is, in the digital car telephone system, as shown in FIG. 2A, the service area 1 is divided into a plurality of wireless zones 2a, 2b, 2c..., And individual frequency control is performed for each of the wireless zones 2a, 2b, 2c. Channels 3a, 3b, 3c,... Are allocated, and control channels 3a, 3b, 3c,... Are transmitted from wireless base stations 4a, 4b, 4c,. . When the mobile station performs the channel switching during communication, as shown in FIG. 2B, using the empty slot I of TDMA, the control channel 3 of the individual frequency provided for each wireless zone is provided.
Channels during communication are switched by sequentially measuring the reception levels of a, 3b, 3c,..., and comparing these reception levels to determine a switching destination wireless zone.
【０００３】一方、スペクトラム拡散を用いた移動通信
方式においては、全ての無線ゾーンに共通な無線周波数
を１つだけ用意し、各無線ゾーンに異なる拡散コードを
割り当て、通信中チャネル切替を行う際は、移動機内の
相関器の１つで拡散コードを走査（スキャン）し、無線
ゾーン毎の受信レベルを測定し比較することにより切替
先の無線ゾーンを決定することにより通信中チャネル切
替を行う方法が考えられる。しかし、このスペクトラム
拡散移動通信方式では無線ゾーン毎にトラヒックのアン
バランスがある場合、最大トラヒックの無線ゾーンにあ
わせて多数の拡散コードを使用可能にするため広帯域の
無線チャネルを用意する必要がある。このためトラヒッ
クの少ない無線ゾーンには過剰設計になる。On the other hand, in a mobile communication system using spread spectrum, only one common radio frequency is prepared for all radio zones, a different spreading code is assigned to each radio zone, and channel switching during communication is performed. A method of performing channel switching during communication by scanning a spreading code with one of the correlators in the mobile device, measuring and comparing the reception level of each wireless zone, and determining the wireless zone to be switched to. Conceivable. However, in this spread spectrum mobile communication system, when there is an imbalance in traffic in each wireless zone, it is necessary to prepare a wideband wireless channel in order to use a large number of spread codes in accordance with the wireless zone of the maximum traffic. For this reason, it is over-designed in a wireless zone with little traffic.
【０００４】これを回避するために一定のトラヒックに
あわせた帯域の無線チャネルを用意し、トラヒックの少
ない無線ゾーンには前記無線チャネルを１チャネルのみ
割り当て、トラヒックが多い無線ゾーンには前記無線チ
ャネルを複数割り当てる構成が考えられる。つまり図３
Ａに示すように一般に、都市の中心部ではトラヒックが
多く、郊外に行くに従って少なくなって行く傾向があ
る。この場合、トラヒックを扱うのに必要な無線チャネ
ル数も図３Ｂに示すように都市の中心部では多く、郊外
に行くに従って少なくする。しかし、このような構成で
通信中チャネル切替を行った場合は、すべての無線ゾー
ンに共通の無線チャネルを用いて移動機が切替先無線ゾ
ーンを決定することになり、複数の無線チャネルが割り
当てられた無線ゾーンで前記共通無線チャネル以外の無
線チャネルで通話中に、切替先無線ゾーンを決定するに
は、共通の無線チャネルに切り替えて受信レベルを測定
する必要があるため通話を切断しないようにするには受
信系を２系統用意しなければならなくなるため移動機の
小型化には適さない。[0004] In order to avoid this, a radio channel having a band corresponding to a certain traffic is prepared, and only one radio channel is allocated to a radio zone with little traffic, and the radio channel is allocated to a radio zone with heavy traffic. A configuration in which a plurality is assigned is conceivable. That is, FIG.
Generally, as shown in A, traffic tends to be high in the center of a city, and tends to decrease in the suburbs. In this case, as shown in FIG. 3B, the number of wireless channels required to handle traffic is large in the center of a city, and is reduced toward the suburbs. However, when the communication channel is switched in such a configuration, the mobile station determines the switching destination wireless zone using the wireless channel common to all the wireless zones, and a plurality of wireless channels are allocated. In order to determine the switching destination wireless zone during a call in a wireless channel other than the common wireless channel in the set wireless zone, it is necessary to switch to the common wireless channel and measure the reception level so that the call is not disconnected. Therefore, it is not suitable for miniaturization of a mobile device because it is necessary to prepare two reception systems.
【０００５】また、これを避けるためにデジタル自動車
電話方式で採用しているように、前記スペクトラム拡散
移動通信においてもＴＤＭＡ的に無線チャネルを構成
し、ＴＤＭＡの空きスロットを利用して切替先無線ゾー
ンを検出する方法が考えられるが、信号がバースト的に
なることにより電磁環境問題（ＥＭＣ）を考慮する必要
があること、ガードビット・同期ビットが必要になりチ
ャネル使用効率が損なわれるという問題がある。In order to avoid this, a radio channel is constructed in a TDMA manner in the spread spectrum mobile communication as employed in the digital car telephone system, and a switching destination radio zone is utilized by utilizing an empty slot of the TDMA. Can be considered, but it is necessary to consider an electromagnetic environment problem (EMC) due to a burst of a signal, and there is a problem that a guard bit / synchronization bit is required and channel use efficiency is impaired. .
【０００６】[0006]
【発明が解決しようとする課題】この発明の目的はトラ
ヒックの少ない無線ゾーンに過剰設計とならず、受信系
を２系統用意する必要がなく、電磁環境の問題をおこす
おそれがなく、通信中チャネル切替を可能とするスペク
トラム拡散移動通信の通信チャネル切替方法を提供する
ことにある。SUMMARY OF THE INVENTION An object of the present invention is not to over-design a wireless zone with little traffic, to eliminate the need to prepare two receiving systems, to avoid the problem of electromagnetic environment, and to improve the communication channel. It is an object of the present invention to provide a communication channel switching method for spread spectrum mobile communication that enables switching.
【０００７】[0007]
【課題を解決するための手段】この発明によれば、サー
ビスエリア内の全ての無線ゾーンに共通な無線周波数を
設け、無線ゾーンごとに前記共通な無線周波数に異なる
制御用拡散コードを割り当て、移動機には２つの相関器
を用意し、通信中にチャネル切替えを行う際には、１つ
の相関器で拡散コードを走査して受信レベルを測定する
ことにより切り替え先無線ゾーンを決定すると共に他の
相関器で通信を継続する。According to the present invention, a common radio frequency is provided for all radio zones in a service area, and a different control spreading code is assigned to the common radio frequency for each radio zone. The device has two correlators, and when switching channels during communication, scans the spreading code with one correlator and measures the reception level to determine the wireless zone to switch to and other channels. Continue communication with the correlator.
【０００８】[0008]
【実施例】図１Ａにこの発明の方法における無線ゾーン
に対する無線周波数の割り当て例を示す。各無線ゾーン
２ａ〜２ｄにそのトラヒック数に応じた数の無線周波数
を割り当てる。図１Ａでは最もトラヒックが多い無線ゾ
ーン２ｂには３つの周波数ｆ1 ，ｆ2 ，ｆ3 を割り当
て、次にトラヒックが多い無線ゾーン２ａ，２ｃにはそ
れぞれ２つの周波数ｆ1 ，ｆ2 を割り当て、最もトラヒ
ックが少ない無線ゾーン２ｄには１つの周波数ｆ1 を割
り当てる。同一周波数については、干渉上影響があるお
それがある領域では無線ゾーンごとに異なる拡散コード
を割り当てる。FIG. 1A shows an example of radio frequency allocation to radio zones in the method of the present invention. Radio frequencies of a number corresponding to the traffic number are allocated to the respective radio zones 2a to 2d. Assign the three frequencies f 1, f 2, f 3 and most traffic in Figure 1A many radio zone 2b, then assign traffic often radio zone 2a, two each of the 2c the frequencies f 1, f 2, most traffic is small radio zone 2d assigning one frequency f 1. For the same frequency, a different spreading code is assigned to each wireless zone in an area where there is a possibility of affecting interference.
【０００９】この発明ではサービスエリア内の全ての無
線ゾーンに共通な無線周波数を割り当てる。図１Ａでは
無線ゾーン２ａ〜２ｄに共通な無線周波数ｆ1 を割り当
て、その無線周波数ｆ1 に対し、各無線ゾーン２ａ〜２
ｄごとに異なる制御用拡散コードを割り当てる。この場
合も、無線ゾーン２ａと２ｄとのように干渉上影響がな
い距離だけ離れている無線ゾーン内では同一の拡散コー
ド、この例ではコード１を繰り返して使用する。According to the present invention, a common radio frequency is allocated to all radio zones in a service area. Allocates a common radio frequency f 1 to the radio zone 2a~2d in Figure 1A, to the radio frequency f 1, the radio zone 2a~2
A different control spreading code is assigned to each d. Also in this case, the same spreading code, code 1 in this example, is used repeatedly in a wireless zone separated by a distance that has no influence on interference, such as the wireless zones 2a and 2d.
【００１０】無線ゾーン２ｂ，２ｃにはそれぞれ共通周
波数ｆ1 に対して制御用拡散コード２，３が割り当てら
れている。請求項１の発明の方法には請求項２の発明の
移動機が用いられる。この移動機は例えば図１Ｂに示す
ように、アンテナ１１は送受共用器１２に接続され、送
受共用器１２に高周波受信増幅器１３及び高周波送信増
幅器１４が接続されている。高周波受信増幅器１３の出
力側にこの発明では二つの相関器１５，１６が接続さ
れ、相関器１５，１６の出力側に変復調部１７が接続さ
れ、変復調部１７から変調信号は送信増幅器１４へ供給
される。相関器１５，１６でそれぞれ設定された拡散コ
ードと一致した受信信号が選出されて変復調部１７で復
調され、拡散逆拡散処理部１８でスペクトラム逆拡散さ
れ、更に信号処理部１９で信号処理され、音声コーディ
ック２１で復号され、音声信号としてハンドセット２２
へ供給される。ハンドセット２２よりの送話音声信号は
音声コーディック２１で符号化され、信号処理部１９で
信号処理され、拡散逆拡散処理部１９でスペクトラム拡
散処理され、変復調部１７で搬送波を変調し、その変調
出力が送信増幅器１４へ供給される。制御部２３で発着
信処理、通話中チャネル切替などを行う。[0010] radio zone 2b, the control spreading codes 2, 3 with respect to each of the 2c common frequency f 1 is assigned. The mobile device of the second invention is used for the method of the first invention. In this mobile device, for example, as shown in FIG. 1B, the antenna 11 is connected to a duplexer 12, and the duplexer 12 is connected to a high-frequency receiving amplifier 13 and a high-frequency transmitting amplifier 14. In the present invention, two correlators 15 and 16 are connected to the output side of the high-frequency receiving amplifier 13, and a modulation / demodulation unit 17 is connected to the output side of the correlators 15 and 16, and the modulation signal is supplied from the modulation / demodulation unit 17 to the transmission amplifier 14. Is done. Received signals that match the spreading codes respectively set by the correlators 15 and 16 are selected, demodulated by the modulation / demodulation unit 17, subjected to spectrum despreading by the spread despreading processing unit 18, further processed by the signal processing unit 19, and subjected to signal processing. The handset 22 is decoded by the voice codec 21 and is converted into a voice signal.
Supplied to The transmitted voice signal from the handset 22 is encoded by the voice codec 21, subjected to signal processing by the signal processing unit 19, subjected to spectrum spread processing by the spread / despread processing unit 19, modulated by the modulation / demodulation unit 17, and modulated by the modulation output. Is supplied to the transmission amplifier 14. The control unit 23 performs outgoing / incoming processing, channel switching during a call, and the like.
【００１１】移動機にはあらかじめ共通の周波数ｆ1 を
示すコードが設定されており、移動機が発信を行う際
は、相関器１５，１６の両者を用いて各無線基地局から
の下り共通周波数信号の受信レベルを測定することによ
り最寄りの無線ゾーンを決定し、その無線ゾーンのコー
ドを用いて接続を行う。この無線ゾーン決定は相関器１
５，１６の一方を用いて行ってもよい。[0011] The mobile station is set with a code previously indicating the common frequency f 1, when the mobile station performs outgoing are downlink common frequency from the radio base station by using both the correlators 15 and 16 The nearest wireless zone is determined by measuring the signal reception level, and a connection is made using the code of the wireless zone. This radio zone is determined by the correlator 1
This may be performed by using one of 5 and 16.
【００１２】いま、移動機が図１Ａの無線ゾーン２ａに
在圈している場合、移動機はｆ1 の周波数の制御用拡散
コード１で発信接続を行った後でｆ2 の周波数で通話を
行う。この通話チャネルの指定、つまり周波数、拡散コ
ードの指定は基地局を通じて制御局により指定されるこ
とは通常の移動通信と同様である。通話中に受信レベル
が低下するあるいは干渉等で通話品質が悪くなると、移
動機は一旦、周波数を共通周波数ｆ1 に切り替え、相関
器１５，１６の１つで通信を継続すると共に、もう１つ
の相関器で拡散コードをスキャン（走査）して下り信号
の受信レベルを測定することにより切り替え先無線ゾー
ンを決定し、例えば、無線ゾーン２ｂが切替先の無線ゾ
ーンであれば無線周波数ｆ2 の拡散コード２のチャネル
か無線周波数ｆ3 の拡散コード１のチャネルに切り替え
て通信を継続する。この周波数及び拡散コードの指定は
制御局から受ける。[0012] Now, when the mobile station is Zai圈the radio zone 2a of FIG. 1A, the mobile station calls a frequency of f 2 after making an outgoing connection control spreading code 1 of the frequency of f 1 Do. The designation of the communication channel, that is, the designation of the frequency and the spreading code is designated by the control station through the base station, similarly to the ordinary mobile communication. If the reception level drops during a call or the call quality deteriorates due to interference or the like, the mobile station temporarily switches the frequency to the common frequency f 1 , continues communication with one of the correlators 15 and 16, and performs another communication. scan the spreading code correlator (scanning) determines the switching destination radio zone by measuring the reception level of the downlink signal, for example, diffusion of the radio frequency f 2 if the radio zone radio zone 2b is the switching destination to continue communication by switching the channel of the spreading codes 1 channel or radio frequency f 3 of the code 2. The designation of the frequency and the spreading code is received from the control station.
【００１３】このように全ての無線ゾーンに共通な無線
周波数ｆ1 のチャネルは、通信中チャネル切替を行う時
に頻繁に使用されるため、無線ゾーンで使用できる無線
周波数が１つしかない場合あるいは無線ゾーンに複数の
無線周波数が割り当てられていてもｆ1 以外の無線周波
数を割り当てる余裕がない場合のみ使用し、通常は通信
中チャネル切替用に空けておくと共に、発着信時の回線
設定等を行うための制御チャネルとして使用する。As described above, the channel of the radio frequency f 1 common to all the radio zones is frequently used when the channel is switched during communication, so that only one radio frequency can be used in the radio zone or be assigned a plurality of radio frequency zones used only when there is no room for allocating radio frequencies other than f 1, usually with set aside for switching during communication channel, performs channel setting or the like during incoming and outgoing call Used as a control channel for
【００１４】[0014]
【発明の効果】以上述べたようにして、この発明を用い
ればスペクトラム拡散を用いたセルラ移動通信方式にお
いて、全ての無線ゾーンに共通な無線周波数を設け、ま
た移動機に２つの相関器を設け、通信中チャネル切替時
に移動機がこの共通な無線周波数に切り替えて二つの相
関器の一方で通信を継続しながら、他方の相関器で切替
先無線ゾーンを決定するため、切替先ゾーン決定のため
に移動機に受信機を２系統持つ必要がないこと、ＴＤＭ
Ａ的に無線チャネルを構成しなくてもよいという効果が
ある。As described above, according to the present invention, in a cellular mobile communication system using spread spectrum, a common radio frequency is provided in all radio zones, and two correlators are provided in a mobile device. In order to determine the switching destination wireless zone with the other correlator while the mobile device switches to this common radio frequency and continues communication on one of the two correlators at the time of channel switching during communication, Need not have two receivers in the mobile device, TDM
There is an effect that it is not necessary to configure a wireless channel in A.
【００１５】また請求項２の発明によれば、相関器が複
数設けられているため、その一つの相関器を用いて通信
を継続しながら、他の相関器を用いて切替先ゾーンを決
定することができ、かつ発信時の在圏ゾーンの決定を、
これら複数の相関器で同時に拡散コードを走査すること
により、短時間で行うことができる。According to the second aspect of the present invention, since a plurality of correlators are provided, communication is continued using one correlator, and a switching destination zone is determined using another correlator. And the determination of the zone in which the call was made,
Scanning the spreading code simultaneously by these plurality of correlators can be performed in a short time.
【図１】Ａは請求項１の発明を適用した無線ゾーンに対
する無線周波数、拡散コードの割り当ての例を示す図、
Ｂは請求項１の発明に用いられる移動機の構成例を示す
ブロック図である。FIG. 1A is a diagram showing an example of assignment of a radio frequency and a spreading code to a radio zone to which the invention of claim 1 is applied;
B is a block diagram showing a configuration example of a transfer motive that used in the first aspect of the present invention.
【図２】Ａはセルラ移動通信方式のゾーン構成の例を示
す図、ＢはＴＤＭＡ方式での空きスロットを利用した受
信レベル測定を示す図である。2A is a diagram illustrating an example of a zone configuration of a cellular mobile communication system, and FIG. 2B is a diagram illustrating reception level measurement using an empty slot in a TDMA system.
【図３】Ａは地域によるトラヒック分布を示す図、Ｂは
この分布と対応した無線チャネルの割り当てを示す図で
ある。3A is a diagram showing a traffic distribution according to a region, and FIG. 3B is a diagram showing assignment of a wireless channel corresponding to the distribution.
Claims (1)
割り当てられているスペクトラム拡散方式を用いたセル
ラ移動通信方式の通信中チャネル切替方法において、各無線ゾーンにそのトラヒックの数に応じた数の無線周
波数をそれぞれ割り当て、 サービスエリア内の全ての無線ゾーンに共通な無線周波
数を設け、 無線ゾーンごとに、前記トラヒックの数に応じた数の無
線周波数及び前記共通な無線周波数に異なる制御用拡散
コードを割り当て、 移動機には２つの相関器を用意し、 通信中にチャネル切替を行う際には、移動機は通信中の
無線周波数から全ての無線ゾーンに共通な無線周波数に
周波数を切り替え、 １つの相関器で拡散コードを走査して受信レベルを測定
することにより切り替え先無線ゾーンを決定すると共に
他の相関器で通信を継続することを特徴とするスペクト
ラム拡散移動通信の通信中チャネル切替方法。1. A communication channel switching method of a cellular mobile communication system using a spread spectrum system in which one or more radio frequencies are allocated to each radio zone , wherein each radio zone has a number corresponding to the number of traffics. Wireless
Assign the wave number, respectively, provided a common radio frequency to all radio zones in a service area, for each radio zone, the number of non-corresponding to the number of the traffic
A different control spreading code is assigned to the line frequency and the common radio frequency, and two correlators are prepared for the mobile device. Switching the frequency to a radio frequency common to the radio zone of the above, scanning the spreading code with one correlator and measuring the reception level to determine the radio zone to switch to and continue communication with the other correlators. Characteristic channel switching method for spread spectrum mobile communication.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05110545A JP3080205B2 (en) | 1993-05-12 | 1993-05-12 | Channel switching method during communication of spread spectrum mobile communication |
| EP94106659A EP0624994B1 (en) | 1993-05-12 | 1994-04-28 | Hand-off method and mobile station for spread spectrum communications system |
| DE69423810T DE69423810T2 (en) | 1993-05-12 | 1994-04-28 | Handover method and mobile station for spread spectrum communication system |
| US08/235,789 US5487083A (en) | 1993-05-12 | 1994-04-29 | Hand-off method and mobile station for spread spectrum mobile communication |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05110545A JP3080205B2 (en) | 1993-05-12 | 1993-05-12 | Channel switching method during communication of spread spectrum mobile communication |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06326653A JPH06326653A (en) | 1994-11-25 |
| JP3080205B2 true JP3080205B2 (en) | 2000-08-21 |
Family
ID=14538545
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05110545A Expired - Fee Related JP3080205B2 (en) | 1993-05-12 | 1993-05-12 | Channel switching method during communication of spread spectrum mobile communication |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3080205B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7283041B2 (en) | 2002-04-26 | 2007-10-16 | Sony Corporation | Side mirror device for vehicle |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3058261B2 (en) * | 1997-05-28 | 2000-07-04 | 日本電気株式会社 | CDMA handoff system, mobile communication cellular system using the same, and base station thereof |
| JP2945357B2 (en) | 1997-07-19 | 1999-09-06 | 松下電器産業株式会社 | Mobile station device and control station device of CDMA system |
| JP3634641B2 (en) | 1998-10-20 | 2005-03-30 | 富士通株式会社 | CDMA mobile communication system |
-
1993
- 1993-05-12 JP JP05110545A patent/JP3080205B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7283041B2 (en) | 2002-04-26 | 2007-10-16 | Sony Corporation | Side mirror device for vehicle |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06326653A (en) | 1994-11-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5487083A (en) | Hand-off method and mobile station for spread spectrum mobile communication | |
| JP3215018B2 (en) | Mobile communication system | |
| EP0546720B1 (en) | Reduced interference through offset frequency partioning in cellular communication systems | |
| KR0146232B1 (en) | Method and apparatus for optimum channel assignments | |
| JP4523171B2 (en) | Using multiple access types in mobile communications | |
| US7904098B2 (en) | Method of assigning transmission channels in a telecommunications network and user station | |
| US5678186A (en) | Digital microcells for cellular networks | |
| JP3073767B2 (en) | Diversity receiver in CDMA cellular telephone system | |
| US5345597A (en) | Call set-up in a radio communication system with dynamic channel allocation | |
| JP4020967B2 (en) | Connection establishment method, subscriber terminal unit and radio system | |
| KR100383686B1 (en) | CDMA transmission system and data transmission method | |
| JP2000125333A (en) | Mobile communication system adopting cdma method | |
| WO2000060893A1 (en) | A communications network and method of allocating resources for soft handover | |
| US6570862B2 (en) | Method for selecting the way to perform a handover, and a cellular radio system | |
| US7092372B1 (en) | Communication protocol for spread sprectrum wireless communication system | |
| JP3080205B2 (en) | Channel switching method during communication of spread spectrum mobile communication | |
| JP3080204B2 (en) | Channel switching method during communication of spread spectrum mobile communication | |
| JP3113539B2 (en) | Mobile communication system | |
| WO1997049200A1 (en) | Communication protocol for spread spectrum wireless communication system | |
| JP3331054B2 (en) | Communication channel selection device | |
| JP3312997B2 (en) | Communication channel switching device | |
| JPH09200841A (en) | Radio channel assignment method | |
| JP3315869B2 (en) | Cell selection method in CDMA mobile communication system | |
| JP3120357B2 (en) | Mobile communication system | |
| JPH0955974A (en) | Mobile communication equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |