JP3156972B2 - FM rebroadcast system - Google Patents
FM rebroadcast systemInfo
- Publication number
- JP3156972B2 JP3156972B2 JP03455691A JP3455691A JP3156972B2 JP 3156972 B2 JP3156972 B2 JP 3156972B2 JP 03455691 A JP03455691 A JP 03455691A JP 3455691 A JP3455691 A JP 3455691A JP 3156972 B2 JP3156972 B2 JP 3156972B2
- Authority
- JP
- Japan
- Prior art keywords
- signal
- monaural
- channels
- frequency
- rebroadcasting
- 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
- 230000005236 sound signal Effects 0.000 claims description 10
- 230000005540 biological transmission Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000012423 maintenance Methods 0.000 description 3
- 230000005684 electric field Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/02—Arrangements for relaying broadcast information
- H04H20/06—Arrangements for relaying broadcast information among broadcast stations
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04H—BROADCAST COMMUNICATION
- H04H20/00—Arrangements for broadcast or for distribution combined with broadcast
- H04H20/53—Arrangements specially adapted for specific applications, e.g. for traffic information or for mobile receivers
- H04H20/59—Arrangements specially adapted for specific applications, e.g. for traffic information or for mobile receivers for emergency or urgency
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Near-Field Transmission Systems (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、例えば自動車トンネル
内などにＦＭ放送を再放送するＦＭ再放送システムに関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FM rebroadcasting system for rebroadcasting FM broadcasts, for example, in a car tunnel.
【０００２】[0002]
【従来の技術】従来、この種のシステムは、到来したＦ
Ｍ電波を受信アンテナおよびＦＭ受信装置によって受信
し、ＦＭ復調を行って音声信号を得る。この音声信号は
再放送装置に与えられ、この再放送装置でＦＭ変調され
る。そして音声信号をＦＭ変調して得られたＦＭ変調信
号を、トンネルなどの再放送対象に設置した送信アンテ
ナに供給し、送信アンテナからＦＭ電波として空中に放
出する。2. Description of the Related Art Conventionally, this type of system has been developed with the F
The M radio wave is received by the receiving antenna and the FM receiver, and FM demodulation is performed to obtain an audio signal. This audio signal is provided to the rebroadcasting apparatus, and FM-modulated by the rebroadcasting apparatus. Then, an FM signal obtained by FM-modulating the audio signal is supplied to a transmission antenna installed at a rebroadcasting target such as a tunnel, and emitted from the transmission antenna into the air as FM radio waves.
【０００３】図２は従来の再放送装置の構成例を示すブ
ロック図である。図中、ＩＮ１，ＩＮ２…，ＩＮｎはそ
れぞれ音声信号の入力端子であり、再放送の対象となる
各チャネルの受信音声信号がＦＭ受信装置から与えられ
る。この入力端子ＩＮ１，ＩＮ２…，ＩＮｎから入力さ
れた音声信号は、リレー接点ｋ1-1 ，ｋ1-2 …，ｋ1-n
のそれぞれを介してステレオ変調器20-1，20-2…，20-n
のそれぞれに入力される。FIG. 2 is a block diagram showing a configuration example of a conventional rebroadcasting apparatus. In the drawing, IN1, IN2,..., INn are input terminals of audio signals, respectively, and receive audio signals of respective channels to be rebroadcast are supplied from the FM receiver. The audio signals input from the input terminals IN1, IN2,..., INn are relay contacts k1-1, k1-2,.
Through each of the stereo modulators 20-1, 20-2 ..., 20-n
Is input to each of.
【０００４】ステレオ変調器20-1〜20-nは、それぞれ対
応するチャネルの周波数ｆ１，ｆ２…，ｆｎの搬送波を
入力された音声信号でＦＭステレオ変調する。ステレオ
変調器20-1〜20-nは、ＦＭステレオ変調を行って得たＦ
Ｍ信号を電力増幅器２１に与える。電力増幅器２１は与
えられたＦＭ信号を電波として放出するのに必要なレベ
ルまで増幅するとともに、各チャネルｆ１〜ｆｎのそれ
ぞれの混合を行い、送信アンテナへと供給する。The stereo modulators 20-1 to 20-n perform FM stereo modulation of carrier waves having frequencies f1, f2,..., Fn of the corresponding channels with the input audio signal. The stereo modulators 20-1 to 20-n perform FM stereo modulation.
The M signal is given to the power amplifier 21. The power amplifier 21 amplifies the given FM signal to a level necessary to emit the signal as a radio wave, mixes each of the channels f1 to fn, and supplies it to the transmitting antenna.
【０００５】ところで、例えば自動車トンネルなどにお
けるＦＭ再放送では、事故情報などの緊急放送が行える
システムとなっている。すなわち図２中において、端子
２２から緊急放送のための割込音声を入力し、この割込
音声を割込音声増幅器２３で増幅する。そして割込音声
増幅器２３で増幅された割込音声をリレー接点ｋ1-1〜
ｋ1-n のそれぞれを介してステレオ変調器20-1〜20-nの
それぞれに入力する。以降、前述した通常の音声の場合
と同様に、ＦＭステレオ変調および電力増幅等を行って
送信アンテナに供される。なお、リレー接点ｋ1-1 〜ｋ
1-n の切り換えは、端子２４を介して外部からなされる
割込制御によりリレーＫ１を駆動して行われる。By the way, for example, in FM rebroadcasting in a car tunnel or the like, an emergency broadcast such as accident information is provided. That is, in FIG. 2, an interrupt sound for an emergency broadcast is input from a terminal 22, and the interrupt sound is amplified by an interrupt sound amplifier 23. Then, the interrupt sound amplified by the interrupt sound amplifier 23 is transferred to the relay contacts k1-1 to k1-1.
Input to each of the stereo modulators 20-1 to 20-n via each of k1-n. Thereafter, as in the case of the above-described normal voice, FM stereo modulation, power amplification, and the like are performed, and the resultant is provided to the transmission antenna. The relay contacts k1-1 to k
The switching of 1-n is performed by driving the relay K1 under interrupt control externally performed via the terminal 24.
【０００６】以上のように従来の再放送装置は、ステレ
オ変調器20-1〜20-nを有している。ここでステレオ変調
器20-1〜20-nは、周波数特性など諸特性をそれぞれの対
応するチャネルの放送局に設置された変調器と一致させ
なければならない等の理由から、非常に高価かつ複雑な
構成である。As described above, the conventional rebroadcasting apparatus has the stereo modulators 20-1 to 20-n. Here, the stereo modulators 20-1 to 20-n are very expensive and complicated because various characteristics such as frequency characteristics have to be matched with the modulators installed in the broadcasting stations of the corresponding channels. Configuration.
【０００７】[0007]
【発明が解決しようとする課題】以上のように従来のＦ
Ｍ再放送システムでは、到来したＦＭ電波は受信アンテ
ナおよび受信装置で受信して音声信号に復調を行ってか
ら再送信装置に入力される。そして、再送信装置ではＦ
Ｍステレオ変調を行って再放送を行っている。このた
め、構成が大型で高価となる復調器や、構成が複雑で高
価なステレオ変調器が、受信装置および再送信装置に必
要となるため、システムが高価となり、またメンテナン
スにも手間および費用がかかるという不具合があった。As described above, the conventional F
In the M rebroadcast system, an incoming FM radio wave is received by a receiving antenna and a receiving device, demodulated into an audio signal, and then input to a retransmitting device. Then, in the retransmission device, F
Rebroadcasting is performed by performing M stereo modulation. For this reason, a large-sized and expensive demodulator and a complicated and expensive stereo modulator are required for the receiving device and the re-transmitting device, so that the system becomes expensive and maintenance is troublesome and costly. There was such a problem.
【０００８】本発明はこのような事情を考慮してなされ
たものであり、その目的とするところは、システムの構
成を簡略化し、これによりシステムのコスト、メンテナ
ンスの手間および費用を低減することができるＦＭ再放
送システムを提供することにある。The present invention has been made in view of such circumstances, and an object of the present invention is to simplify the system configuration, thereby reducing the cost of the system, the time and effort for maintenance, and the cost. It is to provide a possible FM rebroadcast system.
【０００９】[0009]
【議題を解決するための手段】本発明は、到来する複数
チャネルのＦＭ電波を受信して高周波のＦＭ信号に変換
して復調を行わずに送出する受信手段と、前記複数のチ
ャネルのそれぞれに対応して設けられ、外部から入力さ
れる音声信号を前記複数のチャネルのそれぞれに対応さ
せてＦＭモノラル変調して各チャネル周波数に対応した
ＦＭモノラル信号を生成する複数のＦＭモノラル変調手
段と、前記受信手段で得られた前記高周波のＦＭ信号お
よび前記ＦＭモノラル変調手段で生成された前記ＦＭモ
ノラル信号とを外部からの指示に応じて択一的に選択す
る選択手段と、この選択手段で選択された前記高周波の
ＦＭ信号または前記ＦＭモノラル信号をＦＭ電波として
空中に放出する送信手段とから構成した。SUMMARY OF THE INVENTION The present invention relates to a receiving means for receiving incoming FM radio waves of a plurality of channels, converting them into high-frequency FM signals, and transmitting them without demodulation; A plurality of FM monaural modulation means provided to correspond to each of the plurality of channels to generate an FM monaural signal corresponding to each channel frequency by performing FM monaural modulation on an audio signal input from the outside in correspondence with each of the plurality of channels; Selecting means for selectively selecting the high-frequency FM signal obtained by the receiving means and the FM monaural signal generated by the FM monaural modulating means in accordance with an instruction from the outside; Transmitting means for emitting the high-frequency FM signal or the FM monaural signal into the air as FM radio waves.
【００１０】[0010]
【作用】このような手段を講じたことにより、本発明で
は到来するＦＭ電波を変換して得られた高周波のＦＭ信
号は音声信号に復調されることなく、再送信装置に伝送
される。そして、再送信装置では、各チャネル毎に分離
された高周波のＦＭ信号と、各チャネルに対応したモノ
ラル変調された外部信号とを切り替えて送信手段に与え
られ、ＦＭ電波として空中に送出する。このため、比較
的構成が簡単で安価なモノラル変調器の数は増えるもの
の、構成が複雑で高価な復調手段とステレオ復調手段が
不要となり、低コストでメンテナンスが容易になるＦＭ
再放送システムを提供できる。According to the present invention, a high frequency FM signal obtained by converting an incoming FM radio wave is transmitted to the retransmitting device without being demodulated into a voice signal. Then, the retransmitting device switches between a high frequency FM signal separated for each channel and a monaurally modulated external signal corresponding to each channel, which is provided to the transmitting means, and sends out to the air as FM radio waves. For this reason, although the number of inexpensive monaural modulators having a relatively simple configuration is increased, an expensive demodulation means and a stereo demodulation means having a complicated configuration are not required, and the FM can be easily maintained at low cost.
A rebroadcast system can be provided.
【００１１】[0011]
【実施例】以下、図面を参照して本発明の一実施例に付
き説明する。図１は本実施例に係るＦＭ再放送システム
の構成を示す図である。なお、図２と同一部分には同一
符号を付し、その詳細な説明は省略する。An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating the configuration of the FM rebroadcast system according to the present embodiment. The same parts as those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof will be omitted.
【００１２】図中、１は到来したＦＭ電波を高周波のＦ
Ｍ信号に変換する受信アンテナである。この受信アンテ
ナ１で得られたＦＭ信号はチューナ２へと与えられる。
チューナ２は、与えられたＦＭ信号中からｆ１〜ｆｎの
それぞれのチャネルの信号を抽出し、これらの信号をパ
ラレルにＦＭ再放送装置３に与える。In FIG. 1, reference numeral 1 denotes a high-frequency F
This is a receiving antenna for converting into an M signal. The FM signal obtained by the receiving antenna 1 is provided to the tuner 2.
The tuner 2 extracts signals of the respective channels f1 to fn from the applied FM signal, and supplies these signals to the FM rebroadcasting apparatus 3 in parallel.
【００１３】ＦＭ再放送装置３では、チューナ２より与
えられた各チャネルｆ１〜ｆｎのそれぞれの信号をリレ
ー接点ｋ1-1 〜ｋ1-n のそれぞれを介して電力増幅器
（混合器）２１へと入力する。In the FM rebroadcasting apparatus 3, the signals of the respective channels f1 to fn given from the tuner 2 are input to the power amplifier (mixer) 21 via the relay contacts k1-1 to k1-n. I do.
【００１４】チューナ２より与えられる各チャネルｆ１
〜ｆｎの信号の入力端ＩＮ１〜ＩＮｎはリレー接点ｋ1-
1 〜ｋ1-n の常閉接点に接続されているが、リレー接点
ｋ1-1 〜ｋ1-n の常開接点には、それぞれモノラル変調
器31-1，31-2…，31-nが接続されている。モノラル変調
器31-1〜31-nは、割込音声増幅器２３で増幅された割込
音声がそれぞれ入力されている。モノラル変調器31-1〜
31-nは、それぞれ対応するチャネルの周波数ｆ１，ｆ２
…，ｆｎの搬送波を発生させるとともに、割込音声でＦ
Ｍモノラル変調する。このモノラル変調器31-1〜31-nで
得られたＦＭ信号も、リレー接点ｋ1-1 〜ｋ1-n を介し
て電力増幅器２１に与えられる。Each channel f1 provided by the tuner 2
Signal input terminals IN1 to INn are connected to a relay contact k1-
1 to k1-n are connected to normally closed contacts, while the normally open contacts of relay contacts k1-1 to k1-n are connected to monaural modulators 31-1, 31-2 ..., 31-n, respectively. Have been. Each of the monaural modulators 31-1 to 31-n receives the interrupt audio amplified by the interrupt audio amplifier 23, respectively. Monaural modulator 31-1 ~
31-n are the frequencies f1 and f2 of the corresponding channels, respectively.
.., Fn and generate F.
M monaural modulation. The FM signals obtained by the monaural modulators 31-1 to 31-n are also supplied to the power amplifier 21 via relay contacts k1-1 to k1-n.
【００１５】電力増幅器２１から出力されるＦＭ信号
は、出力端子ＯＵＴを介して、トンネルＴＮに布設され
た漏洩同軸ケーブル（ＬＣＸ：leaky-coaxial-cable ）
４に供給される。ＬＣＸ４はその終端に終端抵抗器５が
接続されており、送信アンテナとして機能する。The FM signal output from the power amplifier 21 is transmitted via an output terminal OUT to a leaky-coaxial-cable (LCX) laid in the tunnel TN.
4 is supplied. The LCX 4 has a terminating resistor 5 connected to its end, and functions as a transmitting antenna.
【００１６】かくして本ＦＭ再放送システムは、到来し
たＦＭ電波を受信して得たＦＭ信号は復調せずにそのま
ま電力増幅器２１に与え、再放送に供する。また割込音
声は、モノラル変調器31-1〜31-nでＦＭモノラル変調す
る。そしてモノラル変調器31-1〜31-nで得られたＦＭ信
号を電力増幅器２１に与え、放送に供する。従って、再
送信装置３はステレオ変調器は不必要で、ステレオ変調
器より簡易な構成で安価なモノラル変調器を備えていれ
ば良く、システムの構成が簡易かつ安価となる。また到
来したＦＭ電波を受信して得たＦＭ信号の復調を行わな
いから、復調器が不要であり、この点においてもシステ
ムの構成が簡易かつ安価となる。Thus, the present FM rebroadcasting system receives the arriving FM radio wave and gives the FM signal to the power amplifier 21 without demodulation, to provide it for rebroadcasting. The interrupted voice is FM-monaural-modulated by the monaural modulators 31-1 to 31-n. Then, the FM signals obtained by the monaural modulators 31-1 to 31-n are supplied to the power amplifier 21 and used for broadcasting. Therefore, the retransmitting device 3 does not need a stereo modulator, and it is sufficient that the retransmitting device 3 includes a monaural modulator that is simpler in configuration than the stereo modulator and is inexpensive. Also, since the FM signal obtained by receiving the arriving FM radio wave is not demodulated, a demodulator is not required, and in this regard, the system configuration is simple and inexpensive.
【００１７】ところで、従来のように一旦復調したのち
に再変調を行ってから再放送を行うと、復調後にフェー
ジング補償等の処理を行うことができるが、受信電界が
強ければこのような処理は必ずしも必要なものではな
く、受信電界が強い等、条件が整う場所において本発明
は極めて効果的である。By the way, if demodulation is performed once, then re-modulated and then re-broadcasted, processing such as fading compensation can be performed after demodulation. However, if the received electric field is strong, such processing is not possible. The present invention is not always necessary, and the present invention is extremely effective in a place where conditions are satisfied, such as a strong reception electric field.
【００１８】なお本発明は上記実施例に限定されるもの
ではない。例えば上記実施例では、自動車トンネル内に
再放送を行うＦＭ再放送システムについて説明している
が、再放送を行う対象は自動車トンネルには限定され
ず、任意の対象であってよい。The present invention is not limited to the above embodiment. For example, in the above embodiment, the FM rebroadcasting system for rebroadcasting in a car tunnel is described. However, the target for rebroadcasting is not limited to a car tunnel, and may be any target.
【００１９】また上記実施例では、ＦＭ信号をチューナ
２で各チャネル毎に分離しているが、分離せずに受信ア
ンテナ１で得たＦＭ信号をそのまま再放送装置３に入力
しても良い。このほか、本発明の要旨を逸脱しない範囲
で種々の変形実施が可能である。In the above embodiment, the FM signal is separated by the tuner 2 for each channel. However, the FM signal obtained by the receiving antenna 1 may be directly input to the rebroadcasting apparatus 3 without separation. In addition, various modifications can be made without departing from the spirit of the present invention.
【００２０】[0020]
【発明の効果】本発明によれば、到来するＦＭ電波をＦ
Ｍ信号に変換する例えば受信アンテナおよびチューナよ
りなる受信手段と、外部から入力される音声信号をＦＭ
モノラル変調してＦＭモノラル信号を生成する例えばモ
ノラル変調器などのＦＭモノラル変調手段と、前記受信
手段で得られた前記ＦＭ信号と前記ＦＭモノラル変調手
段で生成された前記ＦＭモノラル信号とを外部からの指
示に応じて択一的に選択する例えばリレーなどの選択手
段と、この選択手段で選択された前記ＦＭ信号または前
記ＦＭモノラル信号をＦＭ電波として空中に放出する、
例えば電力増幅器および漏洩同軸ケーブルからなる送信
手段とからシステムを構成したので、従来のようにシス
テム内にステレオ変調器を設ける必要がなく、システム
の構成が簡略化する。これによりシステムのコスト、メ
ンテナンスの手間および費用を低減することができるＦ
Ｍ再放送システムとなる。According to the present invention, an incoming FM radio wave is
A receiving means for converting the signal into an M signal, for example, a receiving antenna and a tuner;
FM monaural modulation means such as a monaural modulator for generating an FM monaural signal by monaural modulation, and the FM signal obtained by the reception means and the FM monaural signal generated by the FM monaural modulation means are externally transmitted. a selection means such as alternatively selecting for example a relay in accordance with the instructions, to release the pre-Symbol FM signal or the FM monaural signal selected by the selection means in the air as an FM radio wave,
For example , since the system is constituted by the power amplifier and the transmission means including the leaky coaxial cable , there is no need to provide a stereo modulator in the system as in the conventional case, and the system configuration is simplified. As a result, the cost of the system, the time and effort for maintenance, and the cost can be reduced.
M rebroadcast system.
【図１】 本発明の一実施例に係るＦＭ再放送システム
の構成を示す図。FIG. 1 is a diagram showing a configuration of an FM rebroadcast system according to one embodiment of the present invention.
【図２】 従来技術を説明する図。FIG. 2 is a diagram illustrating a conventional technique.
１…受信アンテナ、２…チューナ、３…再放送装置、２
１…電力増幅器、２３…割込音声増幅器、31-1〜31-n…
モノラル変調器、Ｋ１…リレー、ｋ1-1 〜ｋ1-n …リレ
ー接点、４…漏洩同軸ケーブル（ＬＣＸ）、５…終端抵
抗器。DESCRIPTION OF SYMBOLS 1 ... Receiving antenna, 2 ... Tuner, 3 ... Rebroadcasting apparatus, 2
1: Power amplifier, 23: Interrupt audio amplifier, 31-1 to 31-n ...
Monaural modulator, K1 relay, k1-1 to k1-n relay contacts, 4 leaky coaxial cable (LCX), 5 termination resistor.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) H04H 1/00 H04B 5/00 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) H04H 1/00 H04B 5/00
Claims (1)
して高周波のＦＭ信号に変換して復調を行わずに送出す
る受信手段と、 前記複数のチャネルのそれぞれに対応して設けられ、外
部から入力される音声信号を前記複数のチャネルのそれ
ぞれに対応させてＦＭモノラル変調して各チャネル周波
数に対応したＦＭモノラル信号を生成する複数のＦＭモ
ノラル変調手段と、 前記受信手段で得られた前記高周波のＦＭ信号および前
記ＦＭモノラル変調手段で生成された前記ＦＭモノラル
信号とを外部からの指示に応じて択一的に選択する選択
手段と、 この選択手段で選択された前記高周波のＦＭ信号または
前記ＦＭモノラル信号をＦＭ電波として空中に放出する
送信手段とを具備したことを特徴とするＦＭ再放送シス
テム。A receiving means for receiving incoming FM radio waves of a plurality of channels, converting the received FM radio waves into high-frequency FM signals and transmitting the demodulated FM signals without demodulation, and provided for each of the plurality of channels; A plurality of FM monaural modulation means for FM-modulating an input audio signal in correspondence with each of the plurality of channels to generate an FM monaural signal corresponding to each channel frequency; and the high-frequency wave obtained by the receiving means. Selecting means for selectively selecting the FM signal and the FM monaural signal generated by the FM monaural modulating means in accordance with an instruction from the outside; and the high-frequency FM signal selected by the selecting means or A retransmission system for transmitting an FM monaural signal into the air as FM radio waves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP03455691A JP3156972B2 (en) | 1991-02-28 | 1991-02-28 | FM rebroadcast system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP03455691A JP3156972B2 (en) | 1991-02-28 | 1991-02-28 | FM rebroadcast system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04273625A JPH04273625A (en) | 1992-09-29 |
| JP3156972B2 true JP3156972B2 (en) | 2001-04-16 |
Family
ID=12417590
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP03455691A Expired - Fee Related JP3156972B2 (en) | 1991-02-28 | 1991-02-28 | FM rebroadcast system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3156972B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007243906A (en) | 2006-02-07 | 2007-09-20 | Toshiba Corp | Broadcasting apparatus for closed space |
| EP2928092A1 (en) * | 2014-04-04 | 2015-10-07 | Institut für Rundfunktechnik GmbH | Transmitter for transmitting an information signal, preferably a warning announcement signal, via substantially all channels of a frequency range |
-
1991
- 1991-02-28 JP JP03455691A patent/JP3156972B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04273625A (en) | 1992-09-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |