JP2830612B2 - Call control system - Google Patents

Call control system

Info

Publication number
JP2830612B2
JP2830612B2 JP4134516A JP13451692A JP2830612B2 JP 2830612 B2 JP2830612 B2 JP 2830612B2 JP 4134516 A JP4134516 A JP 4134516A JP 13451692 A JP13451692 A JP 13451692A JP 2830612 B2 JP2830612 B2 JP 2830612B2
Authority
JP
Japan
Prior art keywords
slave station
station
circuit
master station
signal
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
Application number
JP4134516A
Other languages
Japanese (ja)
Other versions
JPH05308314A (en
Inventor
雅彦 辻
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
Nippon Electric 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 Nippon Electric Co Ltd filed Critical Nippon Electric Co Ltd
Priority to JP4134516A priority Critical patent/JP2830612B2/en
Publication of JPH05308314A publication Critical patent/JPH05308314A/en
Application granted granted Critical
Publication of JP2830612B2 publication Critical patent/JP2830612B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02DCLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00Reducing energy consumption in communication networks
    • Y02D30/70Reducing energy consumption in communication networks in wireless communication networks

Landscapes

  • Mobile Radio Communication Systems (AREA)
  • Power Sources (AREA)

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION 【産業上の利用分野】[Industrial applications]

【0001】本発明は一つの親局と、複数の子局とから
構成される無線通信システムの親局用送受信装置及び子
局用送受信装置に関する。
The present invention relates to a master station transmitting / receiving apparatus and a slave station transmitting / receiving apparatus of a wireless communication system including one master station and a plurality of slave stations.

【0002】[0002]

【従来の技術】従来例について図3及び図4を参照して
説明する。図3は、従来の無線通信システムの子局用送
受信装置の一例を示すブロック図である。同図に示すよ
うにソーラーパネル111をその電源とする子局用送受
信装置は、ソーラーパネル111によって発電された電
力を一時バッテリー110に充電し、更に各回路に電力
を供給しており、子局はこれらバッテリー110とソー
ラーパネル111で構成されるソーラーバッテリーから
の電力を使用して親局と通信を行う。
2. Description of the Related Art A conventional example will be described with reference to FIGS. FIG. 3 is a block diagram illustrating an example of a transmitting / receiving device for a slave station in a conventional wireless communication system. As shown in the figure, the slave station transmitting / receiving apparatus using the solar panel 111 as a power source temporarily charges the battery 110 with the power generated by the solar panel 111 and further supplies power to each circuit. Communicates with the master station using power from a solar battery composed of the battery 110 and the solar panel 111.

【0003】親局から送出された下り無線周波数信号1
1を子局用無線受信回路101により受信し、子局用無
線受信回路101より得られた第一の子局用受信信号1
2は、子局用受信信号処理回路103により子局用受信
データ32に変換される。子局用受信データ32は子局
用端末インターフェース回路104を介して各端末へ伝
達される。又、各端末より送出されたデータは子局用端
末インターフェース回路104により収集され、子局用
送信データ42となる。子局用送信データ42は子局用
送信信号処理回路105により子局用処理信号52に変
換され、子局用処理信号52は子局用無線送信回路10
6により上り無線周波数信号21として親局に送出され
る様になっている。
[0003] Downlink radio frequency signal 1 transmitted from the master station
1 is received by the slave station wireless receiving circuit 101, and the first slave station reception signal 1 obtained from the slave station wireless receiving circuit 101.
2 is converted by the slave station received signal processing circuit 103 into slave station received data 32. The slave station reception data 32 is transmitted to each terminal via the slave station terminal interface circuit 104. The data transmitted from each terminal is collected by the terminal interface circuit for child station 104 and becomes the transmission data for child station. The slave station transmission data 42 is converted into a slave station processing signal 52 by the slave station transmission signal processing circuit 105, and the slave station processing signal 52 is converted into the slave station radio transmission circuit 10.
6 is transmitted to the master station as an uplink radio frequency signal 21.

【0004】又、図4は、従来の無線通信システムの親
局用送受信装置の一例を示すブロック図である。同図に
示すように親局用送受信装置は、子局から送出された上
り無線周波数信号21を親局用無線受信回路201によ
り受信し、親局用無線受信回路201より得られた親局
用受信信号13は親局用受信信号処理回路203により
親局用受信データ33に変換される。親局用受信データ
33は親局用端末インターフェース回路204を介して
各端末へ伝達される。又、各端末より送出されたデータ
は親局用端末インターフェース回路204により収集さ
れ、親局用送信データ43となる。親局用送信データ4
3は親局用送信信号処理回路205により親局用処理信
号53に変換され、親局用処理信号53は親局用無線送
信回路206により下り無線周波数信号11として子局
に送出される様になっている。
FIG. 4 is a block diagram showing an example of a master station transmitting / receiving apparatus in a conventional radio communication system. As shown in the figure, the master station transmission / reception apparatus receives the uplink radio frequency signal 21 transmitted from the slave station by the master station radio reception circuit 201, and obtains the master station radio reception circuit 201 obtained from the master station radio reception circuit 201. The received signal 13 is converted into the received data 33 for the master station by the received signal processing circuit 203 for the master station. The master station reception data 33 is transmitted to each terminal via the master station terminal interface circuit 204. The data transmitted from each terminal is collected by the parent station terminal interface circuit 204 and becomes transmission data 43 for the parent station. Master station transmission data 4
3 is converted by the master station transmission signal processing circuit 205 into the master station processing signal 53, and the master station processing signal 53 is transmitted to the slave station as the downlink radio frequency signal 11 by the master station wireless transmission circuit 206. Has become.

【0005】[0005]

【発明が解決しようとする課題】上述した従来の無線通
信システムにおいて、ソーラーバッテリーを電源とする
子局用送受信装置では、気象状況や回線の使用状況など
の要因により電源電力が過剰に低下することがある。こ
のようなときに、子局の発着信を無制限に行うと電力が
過剰に低下され、子局用送受信装置を作動させる事が出
来なくなり、これにより回線断やシステムの停止などの
障害や、バッテリー交換などの保守完了までにかかる長
時間にわたるシステムの停止などの障害を発生するとい
う問題がある。本発明の目的は、ソーラーバッテリの電
力低下に応じて発着信数を制限し、子局用送受信装置の
作動不能による回線断等を未然に防止する発着信制御シ
ステムを提供することにある。
In the above-mentioned conventional radio communication system, the power transmitting / receiving device for a slave station using a solar battery as a power source has a problem that the power source power is excessively reduced due to factors such as weather conditions and line usage conditions. There is. In such a case, if the transmission / reception of the slave station is performed unlimitedly, the power will be excessively reduced and the transmission / reception device for the slave station will not be able to operate. There is a problem that a failure such as a long system stoppage required for completion of maintenance such as replacement occurs. An object of the present invention is to provide a transmission / reception control system that limits the number of transmissions / receptions according to a decrease in the power of a solar battery, and prevents a line disconnection or the like due to an inability to operate a slave station transmission / reception device.

【0006】[0006]

【課題を解決するための手段】本発明は、ソーラーバッ
テリを電源とする子局には、ソーラーバッテリーの電力
低下を検出して親局に対してアラーム信号を出力する手
段を有し、親局には、このアラーム信号により子局の発
着信数を可変的に制御する信号を出力する手段を有し、
更に子局には、この制御信号により発着信数の制御を行
う手段を備える。
According to the present invention, a slave station powered by a solar battery has means for detecting a decrease in the power of the solar battery and outputting an alarm signal to the master station. Has means for outputting a signal for variably controlling the number of incoming and outgoing calls of the slave station by this alarm signal,
Further, the slave station is provided with a means for controlling the number of outgoing and incoming calls based on the control signal.

【0007】[0007]

【実施例】次に、本発明について図面を参照して説明す
る。図1は本発明の子局用送受信装置の一実施例のブロ
ック図である。同図において、子局用送受信装置はソー
ラーパネル111によって発電された電力を一時バッテ
リー110に充電し、更に各回路に電力を供給してお
り、子局はこれらで構成されるソーラーバッテリーから
の電力を使用して親局と通信を行う。
Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an embodiment of a transmitting / receiving apparatus for a slave station according to the present invention. In the figure, the slave station transmission / reception device temporarily charges the battery 110 with the power generated by the solar panel 111, and further supplies power to each circuit. Use to communicate with the master station.

【0008】子局用無線受信回路101は親局から受信
した下り無線周波数信号11を受信する。制御信号検出
回路102はこの受信した子局用受信信号12から子局
用制御信号62を検出する。子局用受信信号処理回路1
03は制御信号検出回路102からの子局用受信信号2
2を子局用受信データ32に変換する。子局用端末イン
ターフェース回路104は子局用受信データ32を各端
末と接続し、かつ各端末からのデータは、子局用端末イ
ンターフェース回路104に収集され子局用送信データ
42となる。子局用発着信数制御回路107は子局用制
御信号62に対応した発着信制御信号72を子局用端末
インターフェース回路104に対して出力する。
[0008] The slave station radio receiving circuit 101 receives the downlink radio frequency signal 11 received from the master station. The control signal detection circuit 102 detects the slave station control signal 62 from the slave station reception signal 12 thus received. Slave station received signal processing circuit 1
03 is a slave station reception signal 2 from the control signal detection circuit 102.
2 is converted into the slave station reception data 32. The slave station terminal interface circuit 104 connects the slave station reception data 32 to each terminal, and data from each terminal is collected by the slave station terminal interface circuit 104 to become slave station transmission data. The slave station transmission / reception number control circuit 107 outputs a transmission / reception control signal 72 corresponding to the slave station control signal 62 to the slave station terminal interface circuit 104.

【0009】子局用送信信号処理回路105は子局用送
信データ42とアラーム信号発生回路109から送出さ
れる子局用アラーム信号92を子局用処理信号52に変
換する。子局用無線送信回路106は子局用処理信号5
2を上り無線周波数信号21として親局に送信する。電
源電力低下検出回路108はソーラーパネル11で発電
されてバッテリー110から供給される電力が予め設定
された基準値よりも下回った場合にその度合いに応じた
電力低下検出信号82を出力する。アラーム信号発生回
路109は電力低下検出信号82を親局に対する子局用
アラーム信号92に変換する。
The slave station transmission signal processing circuit 105 converts the slave station transmission data 42 and the slave station alarm signal 92 sent from the alarm signal generation circuit 109 into the slave station processing signal 52. The slave station wireless transmission circuit 106 outputs the slave station processing signal 5
2 is transmitted to the master station as an uplink radio frequency signal 21. When the power generated by the solar panel 11 and the power supplied from the battery 110 falls below a preset reference value, the power supply power drop detection circuit 108 outputs a power drop detection signal 82 corresponding to the degree. The alarm signal generation circuit 109 converts the power drop detection signal 82 into a slave station alarm signal 92 for the master station.

【0010】図2は本発明の親局用送受信装置の一実施
例のブロック図である。同図において親局用送受信装置
は、無線周波数信号を用いて子局に対して通信を行う。
親局用無線受信回路201は子局から受信した上り無線
周波数信号21を受信する。アラーム信号検出回路20
2はその受信した親局用受信信号13から親局用アラー
ム信号63を検出する。親局用受信信号処理回路203
はアラーム信号検出回路202で受信した親局用受信信
号23を親局用受信データ33に変換する。親局用端末
インターフェース回路204は親局用受信データ33を
各端末と接続し、かつ各端末からのデータは、親局用端
末インターフェース回路204に収集され親局用送信デ
ータ43となる。
FIG. 2 is a block diagram of an embodiment of the transmission / reception apparatus for a master station according to the present invention. In the figure, the master station transmission / reception device communicates with the slave station using a radio frequency signal.
The master station radio receiving circuit 201 receives the uplink radio frequency signal 21 received from the slave station. Alarm signal detection circuit 20
2 detects a master station alarm signal 63 from the received master station reception signal 13. Master station received signal processing circuit 203
Converts the master station reception signal 23 received by the alarm signal detection circuit 202 into master station reception data 33. The master station terminal interface circuit 204 connects the master station reception data 33 to each terminal, and data from each terminal is collected by the master station terminal interface circuit 204 to become master station transmission data 43.

【0011】親局用送信信号処理回路205は親局用送
信データ43と制御信号発生回路208から送出される
制御信号83を親局用処理信号53に変換する。親局用
無線送信回路206は親局用処理信号53を下り無線周
波数信号11として子局に送信する。親局用発着信数制
御回路207は親局用アラーム信号63に対応して子局
の発着信数を可変的に制御し、親局用制御信号73を出
力する。制御信号発生回路208は親局用制御信号73
を子局を制御するための制御信号83に変換する。
The transmission signal processing circuit 205 for the master station converts the transmission data 43 for the master station and the control signal 83 sent from the control signal generation circuit 208 into the processing signal 53 for the master station. The master station wireless transmission circuit 206 transmits the master station processing signal 53 to the slave station as the downlink radio frequency signal 11. The master station outgoing / incoming number control circuit 207 variably controls the outgoing / incoming number of the slave station in response to the master station alarm signal 63, and outputs the master station control signal 73. The control signal generating circuit 208 controls the master station control signal 73.
Is converted into a control signal 83 for controlling the slave station.

【0012】続いて本実施例の動作について図1及び図
2を参照して説明する。図1の子局において、電源電力
低下検出回路108はバッテリー110から供給される
電力が予め設定された基準値よりも下回った場合に、そ
の度合いに応じた電力低下検出信号82をアラーム信号
発生回路109に対して出力する。アラーム信号発生回
路109は電力低下検出信号82に対応した子局用アラ
ーム信号92を子局用送信信号処理回路105に出力す
る。そして子局の供給電力低下の情報は子局用送信信号
処理回路105及び子局用無線送信回路106を経て、
上り無線周波数信号21として親局に伝達される。
Next, the operation of this embodiment will be described with reference to FIGS. In the slave station shown in FIG. 1, when the power supplied from the battery 110 falls below a preset reference value, the power supply drop detection circuit 108 outputs a power drop detection signal 82 corresponding to the degree thereof to an alarm signal generation circuit. 109 is output. The alarm signal generation circuit 109 outputs the slave station alarm signal 92 corresponding to the power drop detection signal 82 to the slave station transmission signal processing circuit 105. Then, the information of the supply power reduction of the slave station passes through the slave station transmission signal processing circuit 105 and the slave station wireless transmission circuit 106,
It is transmitted to the master station as an uplink radio frequency signal 21.

【0013】図2の親局において、子局の供給電力低下
の情報は、アラーム信号検出回路202により検出され
親局用アラーム信号63として出力される。親局用発着
信数制御回路207は親局用アラーム信号63から子局
の発着信数をどの程度制限するかを判断し親局用制御信
号73を出力する。制御信号発生回路208は親局用制
御信号73を子局を制御するための制御信号83に変換
する。そして子局に対する発着信数の制御情報は親局用
送信信号処理回路205及び親局用無線送信回路206
を経て、下り無線周波数信号11として子局に伝達され
る。
In the master station shown in FIG. 2, information on a decrease in power supplied to the slave station is detected by an alarm signal detection circuit 202 and output as an alarm signal 63 for the master station. The master station transmission / reception number control circuit 207 determines from the master station alarm signal 63 how much the number of transmission / reception of the slave station should be limited, and outputs a master station control signal 73. The control signal generation circuit 208 converts the master station control signal 73 into a control signal 83 for controlling the slave station. The control information of the number of transmissions and receptions for the slave station is transmitted to the master station transmission signal processing circuit 205 and the master station wireless transmission circuit 206
And transmitted to the slave station as a downlink radio frequency signal 11.

【0014】図1の子局において、発着信数の制御情報
は制御信号検出回路102より検出され子局用制御信号
62として出力される。子局用発着信数制御回路107
は子局用制御信号62から発着信数をどの程度制限する
かを認識し、それに対応した発着信制御信号72を子局
用端末インターフェース回路104に対して出力する。
子局用端末インターフェース回路104は発着信制御信
号72を受け、この信号に対応して子局用端末インター
フェース回路104に接続されている各端末に対する発
着信数を可変的に制限する事が出来る。
In the slave station shown in FIG. 1, the control information of the number of incoming and outgoing calls is detected by the control signal detection circuit 102 and output as a slave station control signal 62. Outgoing / incoming call number control circuit 107 for slave station
Recognizes how much the number of outgoing / incoming calls is restricted from the slave station control signal 62, and outputs a corresponding incoming / outgoing call control signal 72 to the slave station terminal interface circuit 104.
The slave station terminal interface circuit 104 receives the transmission / reception control signal 72, and can variably limit the number of calls to / from each terminal connected to the slave station terminal interface circuit 104 in response to this signal.

【0015】[0015]

【発明の効果】以上説明したように本発明は、電源電力
低下検出回路、アラーム信号発生回路を用いて子局のバ
ッテリーの電力供給状況を監視させ、この情報を親局に
伝達し、親局の持つ親局用発着信数制御回路及び制御信
号発生回路の制御により、子局に接続されている各端末
に対する発着信数を可変的に制限する事により、バッテ
リーからの供給電力の過剰な低下による回線断やシステ
ムの停止などの障害や、バッテリー交換などの保守完了
までにかかる長時間にわたるシステムの停止などの障害
を防止する事ができ、更に親局に於いて子局の電力供給
状況が把握出来る事により保守管理の面に於いても効率
化を計る事が出来るという効果が得られる。
As described above, according to the present invention, the power supply state of the battery of the slave station is monitored by using the power supply drop detection circuit and the alarm signal generation circuit, and this information is transmitted to the master station. The power supply from the battery is excessively reduced by variably limiting the number of transmissions / receptions for each terminal connected to the slave station by controlling the number of transmission / reception number control circuit for the master station and the control signal generation circuit. It can prevent failures such as line disconnection and system stoppage due to power failure and system stoppage for a long time until maintenance is completed, such as battery replacement, and the power supply status of the slave station at the master station can be prevented. By being able to grasp, it is possible to obtain the effect that efficiency can be improved in the aspect of maintenance management.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明の子局用送受信装置の一実施例のブロッ
ク図である。
FIG. 1 is a block diagram of an embodiment of a transmitting / receiving device for a slave station according to the present invention.

【図2】本発明の親局用送受信装置の一実施例のブロッ
ク図である。
FIG. 2 is a block diagram of an embodiment of a transmission / reception device for a master station according to the present invention.

【図3】従来の子局用送受信装置の一例のブロック図で
ある。
FIG. 3 is a block diagram of an example of a conventional transmission / reception device for a slave station.

【図4】従来の親局用送受信装置の一例のブロック図で
ある。
FIG. 4 is a block diagram of an example of a conventional master station transmitting / receiving apparatus.

【符号の説明】[Explanation of symbols]

101 子局用無線受信回路 102 制御信号検出回路 103 子局用受信信号処理回路 104 子局用端末インターフェース回路 105 子局用送信信号処理回路 106 子局用無線送信回路 107 子局用発着信数制御回路 108 電源電力低下検出回路 109 アラーム信号発生回路 110 バッテリー 111 ソーラーパネル 201 親局用無線受信回路 202 アラーム信号検出回路 203 親局用受信信号処理回路 204 親局用端末インターフェース回路 205 親局用送信信号処理回路 206 親局用無線送信回路 207 親局用発着信数制御回路 208 制御信号発生回路 Reference Signs List 101 wireless reception circuit for slave station 102 control signal detection circuit 103 reception signal processing circuit for slave station 104 terminal interface circuit for slave station 105 transmission signal processing circuit for slave station 106 wireless transmission circuit for slave station 107 control of transmission / reception number for slave station Circuit 108 Power drop detection circuit 109 Alarm signal generation circuit 110 Battery 111 Solar panel 201 Master station wireless reception circuit 202 Alarm signal detection circuit 203 Master station reception signal processing circuit 204 Master station terminal interface circuit 205 Master station transmission signal Processing circuit 206 Master station wireless transmission circuit 207 Master station transmission / reception number control circuit 208 Control signal generation circuit

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】 親局と、ソーラーバッテリーを電源とす
る子局とで構成される無線通信システムにおいて、前記
子局には、ソーラーバッテリーの電力低下を検出して前
記親局に対してアラーム信号を出力する手段を有し、前
記親局には、このアラーム信号により前記子局の発着信
数を可変的に制御する信号を出力する手段を有し、更に
前記子局には、この制御信号により発着信数の制御を行
う手段を備えることを特徴とする発着信数制御システ
ム。
1. A wireless communication system comprising a master station and a slave station powered by a solar battery, wherein the slave station detects a decrease in power of the solar battery and issues an alarm signal to the master station. The master station has a means for outputting a signal for variably controlling the number of incoming and outgoing calls of the slave station based on the alarm signal, and the slave station further includes a control signal A means for controlling the number of outgoing / incoming calls according to (1).
JP4134516A 1992-04-28 1992-04-28 Call control system Expired - Fee Related JP2830612B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4134516A JP2830612B2 (en) 1992-04-28 1992-04-28 Call control system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4134516A JP2830612B2 (en) 1992-04-28 1992-04-28 Call control system

Publications (2)

Publication Number Publication Date
JPH05308314A JPH05308314A (en) 1993-11-19
JP2830612B2 true JP2830612B2 (en) 1998-12-02

Family

ID=15130157

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4134516A Expired - Fee Related JP2830612B2 (en) 1992-04-28 1992-04-28 Call control system

Country Status (1)

Country Link
JP (1) JP2830612B2 (en)

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2816781C2 (en) * 1978-04-18 1979-12-20 Siemens Ag, 1000 Berlin Und 8000 Muenchen Device for automatic monitoring of the charge status of mains-independent power supplies
JPS6477231A (en) * 1988-04-06 1989-03-23 Toshiba Corp Radio telephone equipment
JPH01282950A (en) * 1988-05-10 1989-11-14 Canon Inc Communication equipment

Also Published As

Publication number Publication date
JPH05308314A (en) 1993-11-19

Similar Documents

Publication Publication Date Title
US20050163088A1 (en) Radio communication method, radio communication system and wireless terminal
TW346712B (en) Load monitoring and management in a CDMA wireless communication system
US6091527A (en) Communications device having an optical bus, and a method for controlling its operation
US5682417A (en) Power saving mobile data communication system using adaptors
JP2830612B2 (en) Call control system
US5289524A (en) Data transmission method and unit
JPH098676A (en) Radio communication feed system
JP3374712B2 (en) Wireless communication terminal
GB2345213A (en) Half-duplex infra-red transceiver that deactivates its receiver when transmitting
JP2976915B2 (en) Wireless communication device
JPH10290485A (en) Radio metering system
EP0450973A2 (en) Radio communication apparatus
JP2836344B2 (en) Transmitter / receiver for wireless communication system
EP1089466A1 (en) Infra-red link
JPH10285647A (en) Radio communication equipment provided with relay function
JPS6318738A (en) Tdma subscriber radio equipment
KR100472027B1 (en) Alarm apparatus having a alarm switch for portable
EP1089465A1 (en) Infra-red link in power-down mode
JP3020643B2 (en) Communication device for train control
KR19980023323U (en) Power management network management device of subscriber system
JPS58175013A (en) Bidirectional radio remote controller
KR20030014050A (en) System for monitoring repeater using bluetooth
JP4272772B2 (en) Reset control device and control method
JP2005175900A5 (en)
JPH1032870A (en) Radio system

Legal Events

Date Code Title Description
LAPS Cancellation because of no payment of annual fees