JPH02249326A - Idle channel designation system - Google Patents
Idle channel designation systemInfo
- Publication number
- JPH02249326A JPH02249326A JP1069226A JP6922689A JPH02249326A JP H02249326 A JPH02249326 A JP H02249326A JP 1069226 A JP1069226 A JP 1069226A JP 6922689 A JP6922689 A JP 6922689A JP H02249326 A JPH02249326 A JP H02249326A
- Authority
- JP
- Japan
- Prior art keywords
- channel
- connector
- mobile phone
- call
- portable telephone
- 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.)
- Pending
Links
- 238000004891 communication Methods 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 11
- 238000001514 detection method Methods 0.000 claims 2
- 238000010586 diagram Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 2
- 238000004904 shortening Methods 0.000 description 2
- 238000012790 confirmation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
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- Mobile Radio Communication Systems (AREA)
Abstract
Description
【発明の詳細な説明】
(1) 発明の属する技術分野
本発明は、移動した場所で電話を発信または着信可能と
するコードレス電話などのシステムで、マルチチャネル
アクセス方式の無線接続を行うとき、必ず空いている通
話チャネルを探して無線接続しているが、この空きチャ
ネルの指定をするための改良された方式に関する。[Detailed Description of the Invention] (1) Technical field to which the invention pertains The present invention relates to a system such as a cordless telephone that can make or receive calls from a mobile location, and when performing a wireless connection using a multi-channel access method. The present invention relates to an improved method for specifying an empty communication channel when searching for an empty communication channel for wireless connection.
(2)従来の技術とその問題点
現行のコードレス電話は、公衆回線に接続された接続装
置と、バッテリーで動く携帯電話機とを無線で接続し、
電話の発信及び着信を行っている。(2) Conventional technology and its problems Current cordless telephones wirelessly connect a connection device connected to a public line and a battery-operated mobile phone.
Makes and receives calls.
無線系は、接続装置の送信機から送出するFlの電波を
携帯電話機の受信機が受信し、携帯電話機の送信機が発
信するflの電波を接続装置の受信貌が受信している(
第1図参照)。Piとflは5%以上離れているのが一
般的であるが、現行ではFlが380MIIZ 、 f
lが250M1lZを用いている。この接続装置及び携
帯電話機が送出可能な電波は数十組あり(現行では89
&11) 、その中の少なくとも一組を制御専用チャネ
ルと定め、通話には使わないようにしている。In the wireless system, the receiver of the mobile phone receives the Fl radio waves sent from the transmitter of the connecting device, and the receiving face of the connecting device receives the FL radio waves sent by the transmitter of the mobile phone.
(See Figure 1). Pi and fl are generally separated by 5% or more, but currently Fl is 380MIIZ, f
l is 250M1lZ. There are several dozen sets of radio waves that this connection device and mobile phone can transmit (currently 89
&11) At least one set of channels is designated as a control-only channel and is not used for telephone calls.
この複数の組の中の一つのチャネルを選ぶには、先行し
て使用しているチャネルを選んでしまうと他の局に混信
を与えるか、または他の局から混信を受けるので、まず
使用に先立って空きの状態をチエツクし、確認した後電
波を送出し混信を防いでいる。これは接続装置並びに携
帯電話機の受信機のスケルチレベルを各々の制御部に取
り込み判定している。この無線制御をマルチチャネルア
クセス方式と呼ばれ一般に広く用いられている。To select one channel from these multiple sets, first select the channel that is being used, because if you select the channel that is already in use, it will cause interference to other stations or receive interference from other stations. It checks in advance to see if it is vacant, and after confirming, transmits radio waves to prevent interference. In this method, the squelch level of the receiver of the connecting device and the mobile phone is taken into each control section and judged. This radio control is called a multi-channel access method and is generally widely used.
無線回線制御の一例の従来例を第2図に示す。A conventional example of radio line control is shown in FIG.
この図は、外部から接続装置に着信があった例である。This figure shows an example in which a call is received from the outside to the connected device.
まず接続装置に着信があると、接続装置の制御部は制御
チャネルの空いていることを確認する。空いていること
を確認すると、予め見つけておいた一つの空き通話チャ
ネルの情報と共に携帯電話機を呼び出す。これを受信し
た携帯電話機は発呼応答信号を接続装置に回答する。こ
の回答により、接続装置、携帯電話機ともども通話チャ
ネルに切り替える。通話チャネルに切り替わると電波送
出前にこのチャネルが空いていることを再確認する。空
きであることが確認できると、携帯電話機はチャネル切
り替え完了信号を上り通話チャネルで接続装置に送出す
る。一方、接続装置は同信号を受信した旨下り通話チャ
ネルで携帯電話機に回答する。斯くて、通話チャネルル
ープが形成でき通話処理(ベル呼び出し等)に入る。First, when a call arrives at the connecting device, the control unit of the connecting device confirms that the control channel is free. When it is confirmed that the mobile phone is free, the mobile phone is called along with the information of one free call channel found in advance. The mobile phone that receives this sends a call response signal to the connection device. Based on this answer, both the connecting device and the mobile phone switch to the communication channel. When switching to a voice channel, reconfirm that this channel is free before transmitting radio waves. When the mobile phone confirms that the channel is free, it sends a channel switching completion signal to the connecting device through the uplink communication channel. On the other hand, the connecting device replies to the mobile phone via the downstream communication channel that it has received the same signal. Thus, a call channel loop can be formed and call processing (such as ringing) can be entered.
以上は正常に接続できた例である。実際は接続失敗、接
続しなおし等がしばしば発生する。この様なケースは接
続装置と携帯電話機とが離れていて電波が弱かったり、
コンピュータ、モータなどのノイズの多い場所であった
り、同様のシステムが多数使われている場合などで発生
しやすい。原因は制御信号のやり取りに用いられる電波
にノイズが混入したり、あるいは接続装置の指定したチ
ャネルが、携帯電話機側で空いていなかったり、あるい
は接続装置と携帯電話機は数十メートル離れているので
、接続装置が確認した「空きJの判定と携帯電話機側で
見た「空き」とは一致しない場合が原理的にありうる。The above is an example of a successful connection. In reality, connection failures, connection re-connections, etc. often occur. In cases like this, the connection device and mobile phone may be far apart and the signal may be weak.
This is likely to occur in locations with a lot of noise from computers, motors, etc., or where many similar systems are used. The cause may be that noise is mixed into the radio waves used for exchanging control signals, or the channel specified by the connecting device is not available on the mobile phone side, or the connecting device and mobile phone are several tens of meters apart. In principle, there is a possibility that the determination of ``vacancy J'' confirmed by the connecting device and the ``vacancy'' seen on the mobile phone side do not match.
また、接続装置の判定したチャネルは携帯電話機の送出
する周波数fxであり、携帯電話機の判定したチャネル
は、接続装置の送出する周波数Fxである両者が一致し
ない場合も出てくる。上記のごとく様々な原因で接続の
し直しが発生する。Further, the channel determined by the connecting device is the frequency fx transmitted by the mobile phone, and the channel determined by the mobile phone is the frequency Fx transmitted by the connecting device.There may be cases where the two do not match. As mentioned above, reconnection occurs for various reasons.
第3図では携帯電話機で接続装置から指定した通話チャ
ネルが塞がっていた場合の例である。途中までの手順は
第2図の同一であるが、接続装置から指定した通話チャ
ネルが塞がっていた場合、携帯電話機はチャネル切り替
え完了信号を送出しない点が異なる(点線で表示)。携
帯電話機は通話チャネルの空きが見付からないので元の
制御チャネルに切り替えて次の指示を持つ。接続装置は
ある時間待っても携帯電話機からチャネル切り替え完了
信号が到着しないので、元の制御チャネルに戻り制御チ
ャネルの空き検出を行う。空きを確認すると、再度発呼
信号と前回とは別の空きチャネルを指定して携帯電話機
に送出する。以降の手続きは第2図に示した場合と同等
である。このため、正常に接続した場合の2倍以上の時
間を要することになる。当然のことながら、何回もリド
・ライを繰り返していると制御nチャネルを長時間占有
してしまうため、他のシステムが使えな(なるという問
題を有していた。また、最悪の場合接続できなくなるこ
とがある。FIG. 3 shows an example of a case where the communication channel specified by the connection device on the mobile phone is blocked. The steps up to the middle are the same as those shown in FIG. 2, except that if the communication channel specified by the connection device is blocked, the mobile phone does not send a channel switching completion signal (indicated by a dotted line). Since the mobile phone cannot find a free communication channel, it switches to the original control channel and receives the next instruction. Even after waiting for a certain period of time, the connecting device does not receive a channel switching completion signal from the mobile phone, so it returns to the original control channel and detects whether the control channel is available. After confirming availability, a calling signal and a different available channel than the previous one are specified and sent to the mobile phone again. The subsequent procedures are the same as those shown in FIG. Therefore, it will take more than twice as long as it would take to connect normally. Naturally, if you repeat redo many times, the control n channel will be occupied for a long time, making other systems unusable.Also, in the worst case, the connection It may not be possible to do so.
(3)発明の目的
本発明は、この様な欠点をなくすため、携帯電話機側で
も予め空きチャネルを探しておき着信または発信時の無
線回線設定時に接続装置から複数の空きチャネル情報を
送出し、このデータの中から一致するものを選んで空き
チャネル指定すれば従来例のような繰り返しが防げるの
で、接続を確実にし、接続時間を短縮し、他のシステム
に対し制御チャネルの明は渡しを短時間に行うようにし
たものである。(3) Purpose of the Invention In order to eliminate such drawbacks, the present invention searches for vacant channels in advance on the mobile phone side, and sends out information on a plurality of vacant channels from a connecting device when setting up a wireless line when receiving or outgoing calls. By selecting a matching one from this data and specifying an empty channel, repetition as in the conventional example can be prevented, ensuring a secure connection, shortening the connection time, and shortening the transfer of the control channel to other systems. It was designed to be done on time.
(4)発明の構成と作用
本発明の接続フローを第4図に示す。以下第4図を参照
しつつ説明する。なお、ハードウェアについては、第1
図に示したものと同一である。(4) Structure and operation of the invention A connection flow of the invention is shown in FIG. This will be explained below with reference to FIG. Regarding hardware, please refer to Part 1.
It is the same as shown in the figure.
まず、接続装置、携帯電話ともども着信1発信のないと
き、時々受信機を動作させ空きチャネルを探し、制御部
の記憶部に空きチャネル情報を複数個記憶しておく。空
きチャネルの判定は第1図に示す受信機からのスケルチ
レベルを制御部に取り込み、ある信号レベル以下である
場合は空きとする。このチャネル番号を制御部の記憶部
に収納し、次に制御部は周波数シンセサイザーに別のチ
ャネルを受信する指令を出し、別のチャネルを受信する
。此処である受信レベル以上であれば記憶部に収納する
ことなくさらに次のチャネルを受信する。この操作を次
々繰り返し5個程度の空きチャネル情報を記憶部に蓄え
ておく。5個程度の空きチャネルが見付かると、制御部
はしばらくこの操作を休み、またしばらくしてから同様
の操作を繰り返し常に新鮮な空きチャネル情報を記憶部
に蓄えておく。First, when there is no incoming call or outgoing call on either the connecting device or the mobile phone, the receiver is operated from time to time to search for an empty channel, and information on a plurality of empty channels is stored in the storage section of the control section. To determine whether a channel is vacant, the squelch level from the receiver shown in FIG. 1 is taken into the control section, and if the signal level is below a certain signal level, it is determined to be vacant. This channel number is stored in the storage section of the control section, and then the control section issues a command to the frequency synthesizer to receive another channel, and receives the other channel. If the reception level is above a certain reception level, the next channel is received without storing it in the storage unit. This operation is repeated one after another to store information on about five vacant channels in the storage section. When about five free channels are found, the control section suspends this operation for a while, and then repeats the same operation after a while to constantly store fresh free channel information in the storage section.
この時点で接続装置に着信があった場合、接続装置は、
携帯電話機を呼び出すため制御チャネルの空きを確認す
る。空きが確認されると、接続装置は下り制御チャネル
(接続装置から携帯電話機)にて発呼信号プラス空きチ
ャネル情報を乗せて携帯電話機宛に信号を送出する。こ
の際、空きチャネル情報は1チヤネルだけでなく少なく
とも3〜5チャネル分送出すると良い結果が得られる。If the connected device receives a call at this point, the connected device will
Check the availability of the control channel to call the mobile phone. When availability is confirmed, the connecting device sends a signal to the mobile phone on a downlink control channel (from the connecting device to the mobile phone) carrying a calling signal plus information on the empty channel. At this time, good results can be obtained by transmitting the vacant channel information not only for one channel but also for at least three to five channels.
これを受けた携帯電話機は、自ら予め探しておいた空き
チャネル情報と接続装置から送られてきた情報と一致す
るかを照合する。両方の信号の中に一致する空き通話チ
ャネルがあると携帯電話機はこれを一つ選び出し、接続
装置宛に上り制御チャネル(携帯電話から接続装置)で
発呼応答信号と共に送出する。接続装置はこれを受信す
ると共に携帯電話ともども使用周波数を指定した通話チ
ャネルに周波数を切り替える。通話チャネルでの電波の
送出に先立ち再確認のためもう一度空き状態を確認する
。空きが確認出来ると、携帯電話機は通話チャネルでチ
ャネル切り替え完了信号を送出し、これを受けた接続装
置はチャネル切り替え確認信号を携帯電話機宛送出して
通話チャネルのループを確立し、通話処理が開始される
。The mobile phone that receives this information checks whether the information sent from the connecting device matches the available channel information that it has searched for in advance. If there is a matching free call channel among both signals, the mobile phone selects one and sends it to the connected device along with a call response signal on an uplink control channel (from the mobile phone to the connected device). The connecting device receives this and switches the frequency to the designated communication channel together with the mobile phone. Before transmitting radio waves on the communication channel, check the availability status again for reconfirmation. Once availability is confirmed, the mobile phone sends a channel switching completion signal on the call channel, and upon receiving this, the connecting device sends a channel switch confirmation signal to the mobile phone to establish a call channel loop and begin call processing. be done.
上記の例では着呼について述べたが発信の場合も同様で
ある。Although the above example deals with incoming calls, the same applies to outgoing calls.
本発明の他の実施例として、第4図と同様に着信の場合
、接続装置から発呼信号が送出されるがここに前記とは
異なり空きチャネル情報を乗せない(図示せず)。これ
を受けた携帯電話機は自ら予め探しておいた空きチャネ
ルを複数個例えば3〜5個発呼応答信号に乗せて接続装
置宛送出する。As another embodiment of the present invention, in the case of an incoming call as in FIG. 4, a calling signal is sent from the connecting device, but unlike the above, free channel information is not carried here (not shown). Upon receiving this, the mobile telephone sets a plurality of vacant channels, for example, 3 to 5, which it has searched in advance, on a call response signal and sends it to the connecting device.
これを受けた接続装置は、自ら予め探しておいた空きチ
ャネル情報と一致するかを照合する。両方の情報の中に
一致するチャネルがあると接続装置はこれを一つ選び出
し、携帯電話機宛に送出する。The connecting device that receives this checks whether it matches the available channel information that it has searched for in advance. If there is a matching channel in both pieces of information, the connecting device selects one and sends it to the mobile phone.
携帯電話機はこれを受信すると共に接続装置ともども使
用周波数を制御チャネルから指定した通話チャネルに周
波数を切り替える。以下上記と同様の手順で接続を行う
。Upon receiving this, the mobile phone and the connected device switch the frequency used from the control channel to the designated communication channel. Follow the same steps as above to connect.
本発明の他の実施例は、携帯電話機側で空き通話チャネ
ルを予備的に探すことなく、接続装置から送られてきた
複数の空きチャネル情報を、ひとつひとつ確認し、確認
の得られた空き通話チャネルを発呼応答信号と共に、接
続装置に対し空きチャネル指定するものである。In another embodiment of the present invention, the mobile phone side does not preliminarily search for free call channels, but instead checks information on a plurality of free channels sent from the connecting device one by one, and selects the confirmed free call channels. This is used to designate an empty channel to the connected device along with the call response signal.
一般に1!帯電話は、待機時バッテリーセービングのた
め間欠的に受信機を動作させている。この受信機が動作
した時に空きチャネルを探しておくのがよい。バッテリ
ーセービングを行わない携帯電話機では、接続装置と同
様の手順でこれらの操作が行われる。Generally 1! Mobile phones operate their receivers intermittently to save battery power during standby. It is a good idea to search for an empty channel when this receiver is activated. For mobile phones that do not perform battery saving, these operations are performed in the same manner as for connected devices.
上記はコードレス電話について説明したが、本発明は、
一般のマルチチャネルアクセス方式の無線通信に適用可
能である。Although the above describes a cordless telephone, the present invention
It is applicable to general multi-channel access method wireless communication.
本発明の第1図の実施例につき、接続装置は直接一般電
話網に接続してもよいが、構内交換機を介しても同様に
動作することは言うま・でもない。In the embodiment of FIG. 1 of the present invention, the connecting device may be connected directly to the general telephone network, but it goes without saying that it will operate in the same way via a private branch exchange.
(5)発明の効果
本発明により、最悪の場合接続できなくなる確率を減少
させることが出来た。また、接続のためのやり直しが低
減できるので、接続に長時間がかかってしまったりする
欠点を改善した。(5) Effects of the Invention According to the present invention, it is possible to reduce the probability that connection will not be possible in the worst case. Furthermore, since the number of redos required for connection can be reduced, the drawback of connection taking a long time has been improved.
また、やり直しによる制御チャネルを長時間占有してし
まうことがな(なったため、他のシステムが使えなくな
るという問題が少なくなった。In addition, because the control channel is no longer occupied for a long time due to redoing, the problem of other systems becoming unusable is reduced.
第1図は本発明並びに従来例を説明するため接続装置並
びに携帯電話からなる無線通信システムのブロックダイ
アグラムを示す図、第2図は従来例の無線回線設定の手
順で順調に接続できた場合を示すフローチャート図、第
3図は従来の無線回線設定手順で接続ミスを起こし再接
続している様子を示すフローチャート図、第4図は本発
明の無線回線設定手順の一例を示す図である。
特許出願人 岩崎通信機株式会社
同 東京電力株式会社Fig. 1 is a diagram showing a block diagram of a wireless communication system consisting of a connection device and a mobile phone to explain the present invention and a conventional example, and Fig. 2 shows a case where a connection is successfully established using the procedure of setting up a wireless line in the conventional example. FIG. 3 is a flowchart showing how a connection error occurs in the conventional wireless line setting procedure and reconnection is performed, and FIG. 4 is a diagram showing an example of the wireless line setting procedure of the present invention. Patent applicant: Iwasaki Tsushinki Co., Ltd. Tokyo Electric Power Company, Inc.
Claims (1)
的に一般電話網と接続され前記携帯電話機と良好に交信
可能な接続装置とから成るマルチチャネルアクセス方式
の無線通信システムにおいて、 前記携帯電話機と前記接続装置は空きチャネルの検知を
行っており、無線回線の接続に先立ち、無線制御チャネ
ルにて該検知結果から複数の空き通話チャネル情報を送
出し、前記携帯電話機と前記接続装置とのうち該空き通
話チャネル情報を受信した一方は該空き通話チャネルデ
ータと前記検知結果に基づく空き通話チャネルデータと
を比較し、一致した空き通話チャネルデータを予め定め
た手続きに従い前記携帯電話機と前記接続装置のうちの
他方に指定、送出するように構成されたことを特徴とす
る無線通話チャネル設定方式。(1) A multi-channel access wireless communication system comprising at least one mobile phone and a connection device that is directly or indirectly connected to a general telephone network and can communicate well with the mobile phone, the mobile phone and the The connecting device detects an empty channel, and before connecting the wireless line, it sends information on a plurality of empty communication channels based on the detection results on the wireless control channel, and selects the available channel between the mobile phone and the connecting device. The party receiving the call channel information compares the free call channel data with the free call channel data based on the detection result, and selects the matched free call channel data from among the mobile phone and the connecting device according to a predetermined procedure. A wireless communication channel setting method characterized in that the wireless communication channel is configured to be designated and transmitted to the other party.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1069226A JPH02249326A (en) | 1989-03-23 | 1989-03-23 | Idle channel designation system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1069226A JPH02249326A (en) | 1989-03-23 | 1989-03-23 | Idle channel designation system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH02249326A true JPH02249326A (en) | 1990-10-05 |
Family
ID=13396599
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1069226A Pending JPH02249326A (en) | 1989-03-23 | 1989-03-23 | Idle channel designation system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH02249326A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH046919A (en) * | 1990-04-24 | 1992-01-10 | Nec Corp | Cordless telephone system |
JPH0420023A (en) * | 1990-05-14 | 1992-01-23 | Tamura Electric Works Ltd | Cordless telephone set |
JPH04293325A (en) * | 1991-03-22 | 1992-10-16 | Nec Corp | Radio telephone set |
US6157837A (en) * | 1996-01-23 | 2000-12-05 | Ntt Mobile Communications Network Inc. | Mobile communication system, network and mobile station |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5930333A (en) * | 1982-08-13 | 1984-02-17 | Nippon Telegr & Teleph Corp <Ntt> | Method for setting radio line |
-
1989
- 1989-03-23 JP JP1069226A patent/JPH02249326A/en active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5930333A (en) * | 1982-08-13 | 1984-02-17 | Nippon Telegr & Teleph Corp <Ntt> | Method for setting radio line |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH046919A (en) * | 1990-04-24 | 1992-01-10 | Nec Corp | Cordless telephone system |
JPH0420023A (en) * | 1990-05-14 | 1992-01-23 | Tamura Electric Works Ltd | Cordless telephone set |
JPH04293325A (en) * | 1991-03-22 | 1992-10-16 | Nec Corp | Radio telephone set |
US6157837A (en) * | 1996-01-23 | 2000-12-05 | Ntt Mobile Communications Network Inc. | Mobile communication system, network and mobile station |
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