JPH08163063A - Method for synchronized broadcast - Google Patents
Method for synchronized broadcastInfo
- Publication number
- JPH08163063A JPH08163063A JP6296308A JP29630894A JPH08163063A JP H08163063 A JPH08163063 A JP H08163063A JP 6296308 A JP6296308 A JP 6296308A JP 29630894 A JP29630894 A JP 29630894A JP H08163063 A JPH08163063 A JP H08163063A
- Authority
- JP
- Japan
- Prior art keywords
- transmission
- optical fiber
- broadcasting
- station
- broadcast
- 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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Abstract
Description
【0001】[0001]
【産業上の利用分野】この発明は、テレビジョン信号ま
たは音声信号の同期放送方法に係り、特にこれら信号で
変調された送信周波数を隣接または極く接近した複数の
送信所に光ファイバケーブルを使用して同時に伝送する
とともに、送信周波数、変調度および遅延時間の同一な
放送電波を前記複数の送信所から輻射させる同期放送方
法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for synchronously broadcasting a television signal or an audio signal, and more particularly to the use of an optical fiber cable at a plurality of transmitting stations whose transmission frequencies modulated by these signals are adjacent to or very close to each other. The present invention relates to a synchronous broadcasting method in which broadcast radio waves having the same transmission frequency, modulation degree and delay time are radiated from the plurality of transmitting stations while being transmitted simultaneously.
【0002】[0002]
【従来の技術】従来、同期放送については種々検討され
てはいるが、未だに統一された技術の見解や手法は実証
されていない。また、変調された高周波信号を光ファイ
バケーブルで伝送する技術は周知であるが、例えば、極
く特定のテレビジョン中継局における受信所〜送信所間
での中間周波数(19.5±3MHz)のみの伝送手法
に使用されたものがある。これは、受信所〜送信所間に
敷設する同軸線への落雷防止対策として開発されたもの
であり、伝送に使用する周波数が低く、伝送する高周波
信号を直接送信周波数として使用する目的で開発された
ものではない。また、この場合、光ファイバケーブル伝
送回線を自己保有する為に、経済的に普及することは困
難であった。2. Description of the Related Art Conventionally, various studies have been made on synchronous broadcasting, but a unified technical view and method have not yet been proved. Further, although a technique of transmitting a modulated high frequency signal through an optical fiber cable is well known, for example, only an intermediate frequency (19.5 ± 3 MHz) between a receiving station and a transmitting station in a very specific television relay station. Have been used for the transmission method. This was developed as a measure to prevent lightning strikes on the coaxial line laid between the receiving station and the transmitting station.The frequency used for transmission is low, and it was developed for the purpose of directly using the high frequency signal to be transmitted as the transmission frequency. Not a thing. Further, in this case, since the optical fiber cable transmission line is owned by itself, it is difficult to spread economically.
【0003】光ファイバを使用した高周波信号の伝送技
術の発表文献としては、藤原伸一、岡野哲弥:「テレビ
中継放送所IF光多重伝送システム」,電子情報通信学
会技報OCS90−66(1991年3月)がある。[0003] As publications on high-frequency signal transmission technology using optical fibers, Shinichi Fujiwara and Tetsuya Okano: "TV relay broadcasting station IF optical multiplex transmission system", IEICE Technical Report OCS 90-66 (March 1991) There is a month.
【0004】[0004]
【発明が解決しようとする課題】従来、同期放送につい
ての最も一般的な手法として、親局送信所から伝送され
る放送電波を受信し、その受信した信号の中から親局の
送信周波数及び変調信号の成分を検出して、子局の送信
周波数及び変調信号成分にその検出成分を再添加するこ
とで同期を図ることが検討されてきた。また、同期制御
信号を別の回線で伝送する例も見られる。しかしこれら
の方法で同期放送を実施することを考えれば非常に複雑
な装置や制御信号の伝送回線が別途必要であること、ま
た技術的にも同期放送実施に必要な条件が総て整わず、
同期放送の利用価値が重要視されていなかった。Conventionally, as the most general method for synchronous broadcasting, a broadcast radio wave transmitted from a master station transmitting station is received, and the transmission frequency and modulation of the master station are selected from the received signals. It has been considered to detect a signal component and re-add the detected component to the transmission frequency of the slave station and the modulated signal component to achieve synchronization. There is also an example in which the synchronization control signal is transmitted on another line. However, considering that synchronous broadcasting is carried out by these methods, a very complicated device and a control signal transmission line are separately required, and technically, all the conditions necessary for carrying out synchronous broadcasting cannot be set up.
The utility value of synchronous broadcasting was not emphasized.
【0005】近年、光ファイバケーブルを使用する技術
的条件は整ってきている。唯、光ファイバケーブルを使
用することによる距離的な条件が憂慮されるが、同期放
送を実施しなければならない条件は、複数の隣接した送
信場所からの同一送信周波数で放送を行う場合のみに限
られることから、光ファイバケーブル使用の距離的な経
費増の条件は無視できる。In recent years, the technical conditions for using an optical fiber cable have been established. However, although there are concerns over the distance condition due to the use of optical fiber cables, the condition that synchronous broadcasting must be carried out is limited to when broadcasting at the same transmission frequency from multiple adjacent transmission locations. As a result, the condition of the cost increase due to the use of the optical fiber cable can be ignored.
【0006】また、近年における情報伝送システムは、
一般電気通信事業者やCATV事業者が情報通信網を保
有している場合が非常に多く、近隣する複数の送信所近
傍にその端末を探すことが可能であり、自己による光フ
ァイバケーブルの保有の理由はなく、その回線を借用す
ることで経費的には非常に安価で済む。これらの事柄を
基礎にして、狭い地域における同期放送のシステム構築
は、高性能、高安定、高信頼で且つ、安価に達成可能の
条件が整ってきた。The information transmission system in recent years is
In many cases, general telecommunications carriers and CATV carriers own information and communication networks, and it is possible to search for the terminal in the vicinity of a plurality of nearby transmitting stations, and it is possible for them to own their own optical fiber cables. There is no reason, and borrowing the line makes the cost very cheap. On the basis of these matters, the construction of a system for synchronous broadcasting in a narrow area has been established with high performance, high stability, high reliability, and low cost.
【0007】本発明は、光ファイバケーブルを使用した
伝送技術の進歩、前述の経済的効果に対する考察に立脚
してなした発明で、その目的は複雑な装置を使用しなく
てもすみ、安価にシステムの構築できる同期放送方法を
提供せんとするものである。The present invention was made on the basis of the advancement of transmission technology using optical fiber cables and the consideration of the above-mentioned economic effect. The purpose of the invention is not to use a complicated device and to be inexpensive. It is intended to provide a synchronous broadcasting method capable of constructing a system.
【0008】[0008]
【課題を解決するための手段】この目的を達成する本発
明同期放送方法は、隣接または極く接近した複数の送信
所から送信周波数、変調度および遅延時間の同一な放送
電波を輻射させるため、放送演奏所内で変調された送信
周波数の高周波信号を、低レベルで、前記複数の送信所
に光ファイバケーブルを使用して同時に伝送するととも
に、前記複数の送信所への前記演奏所からの路程差は、
別に設けた中央センタ内で光ファイバケーブルの長さを
調節して同一としたことを特徴とするものである。The synchronous broadcasting method of the present invention which achieves this object radiates broadcast radio waves having the same transmission frequency, modulation factor and delay time from a plurality of adjacent or very close transmitting stations. A high-frequency signal of a transmission frequency modulated in a broadcasting station is simultaneously transmitted at a low level to the plurality of transmitting stations by using an optical fiber cable, and a path difference from the playing station to the plurality of transmitting stations is transmitted. Is
It is characterized in that the lengths of the optical fiber cables are adjusted to be the same in a separately provided central center.
【0009】[0009]
【実施例】放送電波において、複数の到来電波が共存す
る場所での受信に関する混信妨害発生の条件は、以下の
とおりである。 送信周波数が同一でない。 変調度が同一でない。 送信周波数及び変調周波数の遅延時間が一定値以上で
ある。 選択する電波のD/U値が一定値以下である。 の条件は、放送局を設置する場合、詳細に検討し、D
/U値を一定値以上になるように設計するが、最近の電
波事情からして必ずしもその条件を満たすことは困難で
ある。の条件値がある程度確保される場合(例えば、
FM放送について言えばD/U比は14dB以上であ
る)、,,についてその条件を満たすことによっ
て受信する場所での混信妨害を低減することが可能にな
る。[Embodiment] The conditions for occurrence of interference in reception in a place where a plurality of incoming radio waves coexist in broadcast radio waves are as follows. The transmission frequencies are not the same. The degree of modulation is not the same. The delay time of the transmission frequency and the modulation frequency is a certain value or more. The D / U value of the selected radio wave is below a certain value. Regarding the conditions, when installing a broadcasting station, consider in detail and
Although the / U value is designed to be a certain value or more, it is difficult to satisfy the condition because of recent radio wave conditions. When the condition value of is secured to some extent (for example,
Speaking of FM broadcasting, the D / U ratio is 14 dB or more) ,,, By satisfying the conditions, it is possible to reduce interference in the receiving place.
【0010】およびの条件については、一般的に、
各送信所においての送信周波数及び変調度は独立してい
るので、相互に同期させることは技術的及び経費的にも
困難である。そこで、本発明により、例えば、以下のよ
うなFM送信システムを構築する。 (a)演奏所にてステレオでFM変調された低電力(11
0dBμv程度)の高周波電波(送信周波数)を出力す
る。 (b)伝送系は光ファイバケーブルを使用して、変調され
た高周波を複数の送信所へ分岐し、伝送する。 (c)各送信所では、伝送された高周波信号を規定の出力
まで増幅し送信する。 以上のシステム構築により、送信周波数及び変調度を同
一とする放送電波を各送信所から発射することができ
る。Regarding the conditions of and, in general,
Since the transmission frequency and the modulation factor at each transmitting station are independent, it is technically and costly difficult to synchronize them with each other. Therefore, according to the present invention, for example, the following FM transmission system is constructed. (a) Low power (11) FM-modulated in stereo at the performance room
A high frequency radio wave (transmission frequency) of about 0 dBμv) is output. (b) The transmission system uses an optical fiber cable to branch and transmit the modulated high frequency waves to multiple transmitting stations. (c) At each transmitting station, the transmitted high frequency signal is amplified to the specified output and transmitted. With the above system construction, it is possible to emit broadcast radio waves having the same transmission frequency and modulation degree from each transmitting station.
【0011】次にによる遅延時間差が問題(例えばF
M放送について言えば遅延時間差は20μsec以下が
要求される)となるが、伝送媒体である光ファイバケー
ブルの長さを伝送途中で調整することで一定値以上に押
さえれば、同期放送としては受信に問題の無い評価が得
られる。The delay time difference due to
In the case of M broadcasting, the delay time difference is required to be 20 μsec or less), but if the length of the optical fiber cable that is the transmission medium is adjusted during transmission to keep it above a certain value, it will be received as synchronous broadcasting. A problem-free evaluation can be obtained.
【0012】以下添附図面を参照し実施例により本発明
方法を詳細に説明する。図1に本発明放送方法に係る実
施例の基本系統図を示す。この例ではFMの同期放送を
例に説明するが、伝送される放送波はこの他テレビジョ
ン放送波でもよければラジオ放送波でもよい。Hereinafter, the method of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a basic system diagram of an embodiment according to the broadcasting method of the present invention. In this example, FM synchronous broadcasting will be described as an example, but the broadcast wave to be transmitted may be a television broadcast wave or a radio broadcast wave.
【0013】市内に設置するFM放送演奏所1におい
て、放送番組信号11を変調信号給電線12を介してF
M変調部13に入力し、FM変調部13でステレオのF
M変調を行う。次にその出力である高周波信号を高周波
信号給電線14を介してE/Oアダプタ(電気/光変換
器)15に入力するが、この時、E/Oアダプタ入力に
はFM放送波帯域(76MHz〜90MHz)の内指定
された1波の送信周波数で110dBμVの電圧を供給
する。E/Oアダプタ15に供給されたFM放送の高周
波信号(送信周波数)は、演奏所1内に引き込まれてい
る既存のCATV事業者の所有する光ファイバケーブル
16によってCATV事業者の中央センタ2へ先ず伝送
される。At the FM broadcasting performance station 1 installed in the city, the broadcasting program signal 11 is transmitted via the modulation signal power supply line 12 to the F
The signal is input to the M modulation unit 13, and the FM modulation unit 13 outputs the stereo F
Perform M modulation. Next, the output high frequency signal is input to the E / O adapter (electrical / optical converter) 15 via the high frequency signal feeder line 14. At this time, the FM broadcast wave band (76 MHz) is input to the E / O adapter input. The voltage of 110 dBμV is supplied at the designated transmission frequency of one wave within 90 MHz). The high frequency signal (transmission frequency) of the FM broadcast supplied to the E / O adapter 15 is sent to the central center 2 of the CATV operator by the optical fiber cable 16 owned by the existing CATV operator that is pulled into the performance room 1. First transmitted.
【0014】次に、この既存のCATV事業者の市内ネ
ットワーク24,25,26を利用して、複数のFM放
送電波の送信所3,4,5近傍まで分岐配信する。この
時、送信所近傍の端末場所から予定する送信場所まで
は、新たに光ファイバケーブルを新設する必要27,2
8,29があるが、大部分CATV事業者の市内ネット
ワーク24,25,26を利用する為にCATV事業者
負担によって行われ、経費は借用料+αで良いことにな
る。Next, by utilizing the existing local networks 24, 25 and 26 of the CATV business operators, branch distribution is performed to the vicinity of a plurality of FM broadcasting radio wave transmitting stations 3, 4 and 5. At this time, it is necessary to newly install an optical fiber cable from the terminal location near the transmission station to the planned transmission location 27,2
Although there are 8 and 29, most of them are carried out by the CATV business operator in order to use the local networks 24, 25 and 26 of the CATV business, and the expense is good with the borrowing fee + α.
【0015】図1図示系統図から、高周波信号(送信周
波数)の各送信所3,4,5への路程差が同期放送条件
である遅延時間差について問題となるが、光ファイバケ
ーブルは極く細い為、CATV中央センタ2内において
その路程差分の長さを調整し同一長とすることが可能で
ある。即ちCATV中央センタ2において、光信号分配
器21の出力に時間差調整ユニット22,23を挿入す
る。これは例えば、各送信所系統における伝送路のうち
一番長い送信所3を基準に取った場合、送信所4及び5
に対する伝送路長差に関する時間差を調整するためであ
る。時間差調整ユニット22,23は光ファイバケーブ
ルを巻いたドラムであり、例えば、1〜20μsec程
度の時間差を調整する。From the system diagram shown in FIG. 1, the path difference of the high frequency signal (transmission frequency) to each of the transmitting stations 3, 4 and 5 causes a problem with respect to the delay time difference which is a condition for synchronous broadcasting, but the optical fiber cable is extremely thin. Therefore, it is possible to adjust the length of the difference in the path lengths in the CATV central center 2 to make them the same length. That is, in the CATV central center 2, the time difference adjusting units 22 and 23 are inserted into the output of the optical signal distributor 21. For example, when the longest transmission station 3 among the transmission lines in each transmission station system is taken as a reference, the transmission stations 4 and 5 are used.
This is to adjust the time difference related to the transmission path length difference with respect to. The time difference adjusting units 22 and 23 are drums around which optical fiber cables are wound, and adjust the time difference of, for example, about 1 to 20 μsec.
【0016】各々分岐配信された高周波信号(送信周波
数)は、各送信所3,4,5に到達し、それぞれのO/
Eアダプタ(光/電気変換器)31,41,51に入力
され、それぞれの出力にはFM放送演奏所1から出力さ
れた高周波信号(送信周波数)が現われる。ここで送信
所3,4,5の各送信部32,42,52には同一条件
の高周波信号(送信周波数)が入力されることになる。
各送信部において、同一遅延時間の規格の機器、即ち入
力フィルタ33,43,53、電力増幅器34,44,
54および出力フィルタ35,45,55を使用すれ
ば、送信部出力すなわち各送信空中線36,46,56
間で送信周波数、変調度、遅延時間の同一な、すなわ
ち、同期のとれたFM放送電波が得られることになる。The high-frequency signals (transmission frequencies) that are branched and distributed reach the transmitting stations 3, 4, and 5 respectively, and the respective O / O
The high frequency signals (transmission frequency) output from the FM broadcasting performance station 1 are input to the E adapters (optical / electrical converters) 31, 41, 51, and output from each of them. Here, a high frequency signal (transmission frequency) of the same condition is input to each of the transmission units 32, 42, 52 of the transmission stations 3, 4, 5.
In each transmitting unit, devices having the same delay time standard, that is, input filters 33, 43, 53, power amplifiers 34, 44,
54 and the output filters 35, 45 and 55, the transmitter output, that is, the respective transmission antennas 36, 46 and 56.
Therefore, FM broadcast radio waves having the same transmission frequency, the same degree of modulation, and the same delay time can be obtained.
【0017】各送信所のサービス・エリア内では、自局
に対して隣接する他の送信所からのFM放送電波が到来
するが(例えば、送信所3のサービス・エリア内に送信
所4,5のFM放送電波が到来する)、自局の電界強度
に対する隣接局の電界強度が約14dB以下である場所
では、FM放送電波として評価の良い受信状況が得られ
ることとなる。この他、テレビジョン放送波やラジオ放
送波についても同様の結果が得られることは明らかであ
る。Within the service area of each transmitting station, FM broadcast waves from other transmitting stations adjacent to the own station arrive (for example, transmitting stations 4, 5 within the service area of transmitting station 3). In the place where the electric field strength of the adjacent station with respect to the electric field strength of the own station is about 14 dB or less, the reception condition evaluated as the FM broadcast wave can be obtained. In addition, it is clear that the same result can be obtained for television broadcast waves and radio broadcast waves.
【0018】光ファイバケーブルは従来は放送局等で、
私設伝送用として架設されてきたが、本発明では一般の
電気通信事業者の所有する光ファイバケーブル伝送回
線、特に、CATV事業者所有の回線を借用することで
経費的に安価な方法を提供している。使用される光ファ
イバケーブルは低損失の伝送特性(伝送損失<0.4d
B/km,接続損失<0.1dB/箇所)を持ち、低出
力レベル遠距離伝送は可能である。The optical fiber cable is conventionally used in broadcasting stations, etc.
Although erected for private transmission, the present invention provides an inexpensive method by renting an optical fiber cable transmission line owned by a general telecommunications carrier, particularly a line owned by a CATV carrier. ing. The optical fiber cable used has low transmission characteristics (transmission loss <0.4d
B / km, connection loss <0.1 dB / location), and low output level long distance transmission is possible.
【0019】以上本発明について、図1図示系統図を参
照し一実施例により詳細に説明してきたが、本発明はこ
の実施例により限定されることなく、本発明の要旨内で
各種の変形、変更の可能なことは当業者に自明であろ
う。Although the present invention has been described in detail with reference to the embodiment shown in FIG. 1, the present invention is not limited to the embodiment, and various modifications can be made within the scope of the present invention. It will be apparent to those skilled in the art that modifications can be made.
【0020】[0020]
【発明の効果】本発明方法を使用すれば複雑な装置を用
いなくても、送信周波数、変調度および遅延時間の同一
な放送電波を複数の送信所から輻射して同期放送を容易
に運用することが可能となり、周波数の有効利用におい
て多大の効果を奏する。また、光ファイバケーブルを自
己保有することが無い為、安価にシステム構築ができ、
さらに、各送信所において、送信装置が簡略化され高信
頼の性能を保つことができ、不要な保守経費支出を低減
できるなどの効果を有する。According to the method of the present invention, synchronous broadcasting can be easily operated by radiating broadcast waves having the same transmission frequency, modulation degree, and delay time from a plurality of transmitting stations without using a complicated device. This makes it possible to achieve a great effect in effective use of frequencies. In addition, because you do not own the optical fiber cable, you can build a system at low cost,
Further, at each transmitting station, the transmitting device can be simplified, highly reliable performance can be maintained, and unnecessary maintenance cost can be reduced.
【図1】本発明同期放送方法に係る実施例の基本系統図
を示す。FIG. 1 shows a basic system diagram of an embodiment according to the synchronous broadcasting method of the present invention.
1 FM放送演奏所 2 中央センタ 3,4,5 送信所 11 放送番組信号 12 変調信号給電線 13 FM変調部 14 高周波信号給電線 15 E/Oアダプタ 16,24,25,26 既設の光ファイバケーブル 21 光信号分配器 22,23 時間差調整ユニット 27,28,29 新設の光ファイバケーブル 31,41,51 O/Eアダプタ 32,42,52 送信部 33,43,53 入力フィルタ 34,44,54 電力増幅器 35,45,55 出力フィルタ 36,46,56 送信空中線 1 FM Broadcasting Theater 2 Central Center 3, 4, 5 Transmitting Station 11 Broadcasting Program Signal 12 Modulation Signal Power Supply Line 13 FM Modulation Section 14 High Frequency Signal Power Supply Line 15 E / O Adapter 16, 24, 25, 26 Existing Fiber Optic Cable 21 Optical signal distributor 22, 23 Time difference adjustment unit 27, 28, 29 Newly installed optical fiber cable 31, 41, 51 O / E adapter 32, 42, 52 Transmitter 33, 43, 53 Input filter 34, 44, 54 Electric power Amplifier 35,45,55 Output filter 36,46,56 Transmission antenna
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鈴木 慎 東京都渋谷区神山町4番14号 株式会社エ ヌエイチケイアイテック内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shin Suzuki 4-14 Kamiyama-cho, Shibuya-ku, Tokyo, N.K.
Claims (1)
(3−5)から送信周波数、変調度および遅延時間の同
一な放送電波を輻射させるため、放送演奏所(1)内で
変調された送信周波数の高周波信号を、低レベルで、前
記複数の送信所に光ファイバケーブルを使用して同時に
伝送するとともに、前記複数の送信所への前記演奏所か
らの路程差は、別に設けた中央センタ(2)内で光ファ
イバケーブルの長さを調節して同一としたことを特徴と
する同期放送方法。1. In order to radiate broadcast radio waves having the same transmission frequency, modulation degree and delay time from a plurality of transmitting stations (3-5) which are adjacent to or very close to each other, they are modulated in the broadcasting station (1). A high-frequency signal having a transmission frequency is simultaneously transmitted at a low level to the plurality of transmitting stations by using an optical fiber cable, and a path difference from the playing place to the plurality of transmitting stations is separately provided in a central center. (2) A synchronized broadcasting method characterized in that the length of the optical fiber cable is adjusted to be the same.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6296308A JPH08163063A (en) | 1994-11-30 | 1994-11-30 | Method for synchronized broadcast |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6296308A JPH08163063A (en) | 1994-11-30 | 1994-11-30 | Method for synchronized broadcast |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH08163063A true JPH08163063A (en) | 1996-06-21 |
Family
ID=17831872
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6296308A Pending JPH08163063A (en) | 1994-11-30 | 1994-11-30 | Method for synchronized broadcast |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH08163063A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006005615A (en) * | 2004-06-17 | 2006-01-05 | Eiden Kk | Single-frequency network digital terrestrial broadcasting system, synchronization system for single-frequency network, and transmitting device |
JP2015091038A (en) * | 2013-11-06 | 2015-05-11 | ホーチキ株式会社 | Relay system for broadcasting |
-
1994
- 1994-11-30 JP JP6296308A patent/JPH08163063A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006005615A (en) * | 2004-06-17 | 2006-01-05 | Eiden Kk | Single-frequency network digital terrestrial broadcasting system, synchronization system for single-frequency network, and transmitting device |
JP2015091038A (en) * | 2013-11-06 | 2015-05-11 | ホーチキ株式会社 | Relay system for broadcasting |
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