JPH07273826A - Modulation multilevel number information transmitting method - Google Patents

Modulation multilevel number information transmitting method

Info

Publication number
JPH07273826A
JPH07273826A JP6059208A JP5920894A JPH07273826A JP H07273826 A JPH07273826 A JP H07273826A JP 6059208 A JP6059208 A JP 6059208A JP 5920894 A JP5920894 A JP 5920894A JP H07273826 A JPH07273826 A JP H07273826A
Authority
JP
Japan
Prior art keywords
modulation
signal
number information
information
transmission
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.)
Granted
Application number
JP6059208A
Other languages
Japanese (ja)
Other versions
JP3301462B2 (en
Inventor
Takashi Okada
岡田  隆
Tadashi Shirato
正 白土
Toshiaki Takao
俊明 高尾
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.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
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Filing date
Publication date
Application filed by Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP05920894A priority Critical patent/JP3301462B2/en
Publication of JPH07273826A publication Critical patent/JPH07273826A/en
Application granted granted Critical
Publication of JP3301462B2 publication Critical patent/JP3301462B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Abstract

PURPOSE:To suppress the transmission error of modulation multilevel number information to a minimum and to reduce the malfunction of a demodulator and the fluctuation of communication quality by transmitting the modulation multilevel number information by inserting the information in the highest order or the prescribed signal series of a transmission signal. CONSTITUTION:A transmission signal (serial signal) to be inputted in a modulator 2 is converted into a one-side (n) series signal (parallel signal) according to a modulation multilevel number (n) and a signal frame for performing an error correction coding, etc., is generated. At this time, because the order of the signal series is established, modulation multilevel number information can be inserted into a highest order or a prescribed signal series. In the modulator 2, after the processing of the frame in which this modulation multilevel number information is inserted is finished, the switching to this modulation multilevel number is performed. In a demodulator 5, modulation multilevel number information is extracted from the highest order or the prescribed signal series and the switching to this modulation multilevel value is performed after the processing of the frame in which the modulation multilevel number information is inserted is finished in the same way as the modulator 2.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、無線信号の変調多値数
を変化させて伝送容量を制御する可変容量伝送方式にお
いて、送信側(変調側)から受信側(復調側)に変調多
値数情報を伝送する変調多値数情報伝送方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable-capacity transmission system in which the transmission capacity is controlled by changing the modulation multi-value number of a radio signal, and the modulation multi-value is transmitted from the transmission side (modulation side) to the reception side (demodulation side). The present invention relates to a modulation multi-level number information transmission method for transmitting number information.

【0002】[0002]

【従来の技術】可変容量伝送方式は、通信回線のトラヒ
ックの変動、無線信号の受信レベルの低下、フェージン
グその他の要因による異常伝搬に応じて伝送容量を制御
するものである。この可変容量伝送方式において変調多
値数を変化させて伝送容量を制御する場合には、送信側
から受信側に変調多値数情報が伝送される。
2. Description of the Related Art A variable capacity transmission system controls a transmission capacity according to fluctuations in traffic of a communication line, reduction in reception level of radio signals, abnormal propagation due to fading and other factors. When controlling the transmission capacity by changing the modulation multilevel number in this variable capacity transmission system, the modulation multilevel number information is transmitted from the transmitting side to the receiving side.

【0003】図4および図5は、従来の変調多値数情報
伝送方法を説明する図である(大内他,“ATM網に対
する無線可変容量伝送方式適用の検討”,電子情報通信
学会論文集B-II,J76-B-II,No.8,pp.661-668, 第4
章)。
FIG. 4 and FIG. 5 are diagrams for explaining a conventional modulation multilevel information transmission method (Ouchi et al., "Study on application of wireless variable capacity transmission method to ATM network", IEICE Transactions). B-II, J76-B-II, No.8, pp.661-668, 4th
chapter).

【0004】図4において、(1) に示す送信装置は、送
信端局装置1,変調器2,送信器3および遅延回路7に
より構成され、(2) に示す受信装置は、受信器4,復調
器5,受信端局装置6および遅延回路7により構成され
る。ここで、図5に示すように、次のフレームの変調方
式に対応する変調多値数情報が送信端局装置1でSDH
フレームの先頭に挿入される。なお、送信装置では、こ
の変調多値数情報は次のフレームの変調処理に用いるの
で、1フレーム相当の遅延τを与える遅延回路7を介し
て変調器2に与えられる。一方、受信端局装置6では受
信信号から変調多値数情報を抽出し、次のフレームの復
調処理に用いるために同様の遅延回路7を介して復調器
5に与える。これにより、変調多値数の切り替えが行わ
れ、伝送容量の制御が行われる。
In FIG. 4, the transmitting device shown in (1) is composed of a transmitting terminal device 1, a modulator 2, a transmitter 3 and a delay circuit 7, and the receiving device shown in (2) is a receiver 4, It is composed of a demodulator 5, a receiving terminal device 6 and a delay circuit 7. Here, as shown in FIG. 5, the modulation multi-value number information corresponding to the modulation method of the next frame is transmitted to the transmitting terminal station device 1 by SDH.
It is inserted at the beginning of the frame. In the transmitting device, this modulation multi-valued information is used for the modulation process of the next frame, and therefore is given to the modulator 2 via the delay circuit 7 which gives a delay τ corresponding to one frame. On the other hand, the receiving terminal device 6 extracts the modulation multi-level information from the received signal and supplies it to the demodulator 5 via the same delay circuit 7 for use in the demodulation processing of the next frame. Thereby, the modulation multi-value number is switched and the transmission capacity is controlled.

【0005】[0005]

【発明が解決しようとする課題】従来の変調多値数情報
伝送方法では、変調多値数情報が無線信号に重畳されて
伝送されるので、変調多値数情報に伝送誤りが生じる可
能性がある。変調多値数情報に伝送誤りが生じた場合に
は、復調器5が誤動作して通信品質が劣化する。
In the conventional method of transmitting modulation multi-level number information, since the modulation multi-level number information is transmitted while being superimposed on the radio signal, a transmission error may occur in the modulation multi-level number information. is there. When a transmission error occurs in the modulated multi-level information, the demodulator 5 malfunctions and communication quality deteriorates.

【0006】一方、多値変調方式における入力信号D1
は、変調多値数をn、各系列信号をa1 〜an とする
と、 D1 =a1・2n-1+a2・2n-2+ … +an・20 と表される。この式からわかるように、第1系列信号
(最上位系列信号)は入力信号の極性を表しており信号
識別は正負判定のみである。したがって、第1系列信号
の誤り率は他の系列信号に比べて低い。また、各系列信
号の誤り率は異なり下位の系列信号ほど誤り率は高くな
る。
On the other hand, the input signal D 1 in the multilevel modulation system
, When the modulation level n, each sequence signal and a 1 ~a n, is expressed as D 1 = a 1 · 2 n -1 + a 2 · 2 n-2 + ... + a n · 2 0. As can be seen from this equation, the first series signal (the highest order series signal) represents the polarity of the input signal, and the signal discrimination is only positive / negative judgment. Therefore, the error rate of the first sequence signal is lower than that of other sequence signals. Moreover, the error rate of each sequence signal is different, and the error rate becomes higher for the lower sequence signals.

【0007】変調器2では、入力されるシリアル信号が
変調方式に応じてシリアル−パラレル(S−P)変換さ
れ、無線回線用の複数のデータ信号系列が生成される。
このとき、SDHフレームとの同期を行わずにS−P変
換されるので、送信端局装置1で挿入された変調多値数
情報がのる信号系列は不確定となる。すなわち、従来の
変調多値数情報伝送方法では、変調多値数情報が下位の
信号系列に挿入されて伝送されることがある。この場合
には変調多値数情報の誤り率が高まり、復調器5の誤動
作が増加して通信品質が著しく劣化する。しかも、変調
多値数情報が挿入される信号系列が不確定であるので通
信品質が変動する要因にもなる。
In the modulator 2, the input serial signal is subjected to serial-parallel (SP) conversion according to the modulation system, and a plurality of data signal sequences for wireless lines are generated.
At this time, since the SP conversion is performed without synchronizing with the SDH frame, the signal sequence carrying the modulation multi-level number information inserted in the transmitting terminal station device 1 becomes indefinite. That is, in the conventional modulation multi-level number information transmission method, the modulation multi-level number information may be inserted into a lower signal sequence and transmitted. In this case, the error rate of the modulation multilevel information increases, the malfunction of the demodulator 5 increases, and the communication quality deteriorates significantly. Moreover, since the signal sequence in which the modulation multi-level information is inserted is uncertain, it also causes a change in communication quality.

【0008】本発明は、変調多値数情報の伝送誤りを最
小限に抑え、復調器の誤動作および通信品質の変動を低
減することができる変調多値数情報伝送方法を提供する
ことを目的とする。
It is an object of the present invention to provide a modulation multilevel information transmission method capable of minimizing the transmission error of the modulation multilevel information and reducing the malfunction of the demodulator and the fluctuation of the communication quality. To do.

【0009】[0009]

【課題を解決するための手段】本発明は、変調多値数情
報を伝送信号の最上位または所定の信号系列中に挿入し
て伝送する。
According to the present invention, modulated multi-valued number information is inserted by being inserted into the most significant or predetermined signal sequence of a transmission signal and transmitted.

【0010】また、伝送信号を多値変調方式に応じてシ
リアル−パラレル変換し、生成された複数の信号系列ご
とにフレーム生成する際に、最上位または所定の信号系
列に変調多値数情報を挿入する。
Further, when the transmission signal is subjected to serial-parallel conversion according to the multi-level modulation method and a frame is generated for each of a plurality of generated signal series, the modulation multi-level number information is added to the highest or a predetermined signal series. insert.

【0011】[0011]

【作用】変調器に入力される伝送信号(シリアル信号)
は、変調多値数nに応じて片チャネルn系列信号(パラ
レル信号)に変換され、誤り訂正符号化等を行うための
信号フレームが生成される。このとき、信号系列の順位
は確定しているので、変調多値数情報を最上位または所
定の信号系列に挿入することができる。なお、変調器で
は、この変調多値数情報が挿入されたフレームの処理が
終わった後に、この変調多値数への切り替えが行われ
る。
[Operation] Transmission signal (serial signal) input to modulator
Is converted into a one-channel n-series signal (parallel signal) according to the modulation multi-value number n, and a signal frame for performing error correction coding and the like is generated. At this time, since the order of the signal sequence is fixed, the modulation multi-level information can be inserted into the highest order or a predetermined signal sequence. In the modulator, switching to the modulation multi-level number is performed after the processing of the frame in which the modulation multi-level number information is inserted is completed.

【0012】一方、復調器では、最上位または所定の信
号系列から変調多値数情報を抽出し、変調器と同様に変
調多値数情報が挿入されたフレームの処理が終わった後
に、この変調多値数への切り替えが行われる。
On the other hand, in the demodulator, the modulation multi-level information is extracted from the highest order or a predetermined signal sequence, and after the processing of the frame in which the modulation multi-level information is inserted is finished like the modulator, this modulation is performed. Switching to multi-valued numbers is done.

【0013】このように、変調多値数情報を挿入する信
号系列を固定することにより変調多値数情報の誤り率が
安定し、復調器の誤動作に伴う通信品質の変動を最小限
に抑えることができる。さらに、変調多値数情報を最上
位の信号系列に挿入することにより変調多値数情報の誤
り率が小さくなり、復調器の誤動作を最小限に抑えて通
信品質の向上を図ることができる。
In this way, by fixing the signal sequence into which the modulation multi-level information is inserted, the error rate of the modulation multi-level information is stabilized, and fluctuations in communication quality due to malfunction of the demodulator are minimized. You can Furthermore, by inserting the modulation multi-level number information into the highest-order signal sequence, the error rate of the modulation multi-level number information is reduced, and the malfunction of the demodulator can be minimized to improve the communication quality.

【0014】[0014]

【実施例】図1は、本発明の変調多値数情報伝送方法を
実現する変調器および復調器の実施例構成を示す。(1)
は変調器2を含む送信装置の構成であり、(2) は復調器
5を含む受信装置の構成である。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment of a modulator and a demodulator for realizing the modulated multilevel information transmission method of the present invention. (1)
Is the configuration of the transmitter including the modulator 2, and (2) is the configuration of the receiver including the demodulator 5.

【0015】図において、送信端局装置1から変調器2
に入力された信号は、シリアル−パラレル変換回路(S
−P)21で片チャネルn系列のパラレル信号に変換さ
れ、誤り訂正符号化のためのフレーム生成を行うフレー
ム生成回路22に入力される。また、通信回線の状況に
応じて設定される変調多値数情報は、フレーム生成回路
22およびフリップフロップ25に直接入力される。フ
レーム生成回路22では、最上位の信号系列(第1信号
系列)または所定の信号系列(例えば第2信号系列)
で、かつ図2に示すように例えば誤り訂正符号化用に生
成されたフレームの所定の位置(制御ビット)に変調多
値数情報を挿入する。なお、図3では最上位の信号系列
に次のフレームにおける変調多値数情報が挿入される様
子を示す。
In the figure, from the transmitting terminal device 1 to the modulator 2
The signal input to the serial-parallel conversion circuit (S
-P) 21 is converted into a parallel signal of one channel n series, and is input to the frame generation circuit 22 that performs frame generation for error correction coding. Further, the modulation multi-level number information set according to the state of the communication line is directly input to the frame generation circuit 22 and the flip-flop 25. In the frame generation circuit 22, the highest-order signal sequence (first signal sequence) or a predetermined signal sequence (for example, second signal sequence)
Then, as shown in FIG. 2, the modulation multi-level information is inserted at a predetermined position (control bit) of the frame generated for error correction coding, for example. Note that FIG. 3 shows a state in which the modulation multi-level number information in the next frame is inserted in the highest-order signal sequence.

【0016】フレーム生成回路22の出力信号は多値数
制御回路23に入力され、変調多値数に応じたドリフト
および利得調整を行って直交変調回路24に送出され
る。直交変調回路24で変調された信号は、送信器3で
無線信号に変換されて送信される。ここで、シリアル/
パラレル変換回路21および多値数制御回路23におけ
る変調多値数の切り替えは、フレーム生成回路22のフ
レーム処理に同期して出力されるパルスに同期して行わ
れる。フリップフロップ25はこのタイミング制御に用
いられる。
The output signal of the frame generation circuit 22 is input to the multi-level number control circuit 23, the drift and gain are adjusted according to the modulation multi-level number, and the quadrature modulation circuit 24 is sent out. The signal modulated by the quadrature modulation circuit 24 is converted into a radio signal by the transmitter 3 and transmitted. Where serial /
Switching of the modulation multi-value number in the parallel conversion circuit 21 and the multi-value number control circuit 23 is performed in synchronization with the pulse output in synchronization with the frame processing of the frame generation circuit 22. The flip-flop 25 is used for this timing control.

【0017】受信装置に受信された信号は、受信器4で
周波数変換された後に直交復調回路51で復調され、多
値数制御回路52に入力される。多値数制御回路52で
は、変調多値数に応じて直交復調回路51における復調
処理のための信号を生成して直交復調回路51に出力す
る。また、多値数制御回路52から出力される復調信号
は、誤り訂正を行うフレーム同期回路53に入力され
る。フレーム同期回路53は、図3に示すように最上位
の信号系列でかつフレームの所定の位置に挿入されてい
る変調多値数情報を抽出してフリップフロップ55に送
出する。フレーム同期回路53で誤り訂正された復調信
号は、パラレル−シリアル変換回路(P−S)54でシ
リアル信号に変換されて受信端局装置6に送出される。
ここで、多値数制御回路52およびパラレル−シリアル
変換回路54における変調多値数の切り替えは、フレー
ム同期回路53のフレーム処理に同期して出力されるパ
ルスに同期して行われる。フリップフロップ55はこの
タイミング制御に用いられる。
The signal received by the receiver is frequency-converted by the receiver 4, demodulated by the quadrature demodulation circuit 51, and input to the multilevel control circuit 52. The multilevel control circuit 52 generates a signal for demodulation processing in the orthogonal demodulation circuit 51 according to the modulation multilevel number and outputs the signal to the orthogonal demodulation circuit 51. The demodulated signal output from the multi-level number control circuit 52 is input to the frame synchronization circuit 53 that performs error correction. As shown in FIG. 3, the frame synchronization circuit 53 extracts the modulation multi-level number information inserted in a predetermined position of the frame in the highest order signal sequence and sends it to the flip-flop 55. The demodulated signal error-corrected by the frame synchronization circuit 53 is converted into a serial signal by the parallel-serial conversion circuit (PS) 54 and sent to the receiving terminal station device 6.
Here, the switching of the modulation multi-value number in the multi-value number control circuit 52 and the parallel-serial conversion circuit 54 is performed in synchronization with the pulse output in synchronization with the frame processing of the frame synchronization circuit 53. The flip-flop 55 is used for this timing control.

【0018】[0018]

【発明の効果】以上説明したように、本発明の変調多値
数情報伝送方法では、変調多値数情報を最も誤りにくい
最上位の信号系列に挿入して伝送することにより、変調
多値数情報の伝送誤りを最小限に抑え、復調器の誤動作
を低減して通信品質の向上を図ることができる。
As described above, according to the modulation multi-value number information transmission method of the present invention, the modulation multi-value number information is inserted into the most significant error-prone signal sequence and transmitted, whereby the modulation multi-value number information is transmitted. It is possible to minimize the information transmission error, reduce the malfunction of the demodulator, and improve the communication quality.

【0019】また、変調多値数情報を所定の信号系列に
挿入して伝送することにより、変調多値数情報の誤り率
が安定し、復調器の誤動作に伴う通信品質の変動を最小
限に抑えることができる。
Further, by inserting the modulation multi-level number information into a predetermined signal sequence and transmitting it, the error rate of the modulation multi-level number information becomes stable, and the fluctuation of the communication quality due to the malfunction of the demodulator is minimized. Can be suppressed.

【0020】なお、本発明の変調多値数情報伝送方法
は、変調器および復調器の内部で処理することができる
ので、高速切り替え動作にも対応することができる。
Since the modulated multilevel information transmission method of the present invention can be processed inside the modulator and the demodulator, it can be applied to a high-speed switching operation.

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

【図1】本発明の変調多値数情報伝送方法を実現する変
調器および復調器の実施例構成を示すブロック図。
FIG. 1 is a block diagram showing a configuration of an embodiment of a modulator and a demodulator that realizes a modulation multilevel information transmission method of the present invention.

【図2】本発明の変調多値数情報伝送方法に用いる信号
フレームの構成例を示す図。
FIG. 2 is a diagram showing a configuration example of a signal frame used in the modulation multi-level number information transmission method of the present invention.

【図3】本発明の変調多値数情報伝送方法の動作原理を
説明する図。
FIG. 3 is a diagram for explaining the operation principle of the modulation multilevel information transmission method of the present invention.

【図4】従来の変調多値数情報伝送方法をとる送信装置
および受信装置の構成を示すブロック図。
FIG. 4 is a block diagram showing a configuration of a transmission device and a reception device adopting a conventional modulation multilevel information transmission method.

【図5】従来の変調多値数情報伝送方法の動作原理を説
明する図。
FIG. 5 is a diagram for explaining the operating principle of a conventional modulated multilevel information transmission method.

【符号の説明】[Explanation of symbols]

1 送信端局装置 2 変調器 3 送信器 4 受信器 5 復調器 6 受信端局装置 7 遅延回路 21 シリアル−パラレル変換回路(S−P) 22 フレーム生成回路 23 多値数制御回路 24 直交変調回路 25 フリップフロップ 51 直交復調回路 52 多値数制御回路 53 フレーム同期回路 54 パラレル−シリアル変換回路(P−S) 55 フリップフロップ DESCRIPTION OF SYMBOLS 1 transmitting end station device 2 modulator 3 transmitter 4 receiver 5 demodulator 6 receiving end station device 7 delay circuit 21 serial-parallel conversion circuit (SP) 22 frame generation circuit 23 multi-valued number control circuit 24 orthogonal modulation circuit 25 flip-flop 51 quadrature demodulation circuit 52 multi-valued number control circuit 53 frame synchronization circuit 54 parallel-serial conversion circuit (P-S) 55 flip-flop

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 通信回線の状況に応じて多値変調方式に
おける変調多値数を変化させて伝送容量を制御する可変
容量伝送システムにおいて、 変調多値数情報を伝送信号の所定の信号系列中に挿入し
て伝送することを特徴とする変調多値数情報伝送方法。
1. A variable capacity transmission system for controlling a transmission capacity by changing a modulation multi-value number in a multi-value modulation method according to a situation of a communication line, wherein modulation multi-value number information is included in a predetermined signal sequence of a transmission signal. A method for transmitting modulated multi-valued information, which is characterized in that it is inserted into a frame and transmitted.
【請求項2】 通信回線の状況に応じて多値変調方式に
おける変調多値数を変化させて伝送容量を制御する可変
容量伝送システムにおいて、 変調多値数情報を伝送信号の最上位の信号系列中に挿入
して伝送することを特徴とする変調多値数情報伝送方
法。
2. A variable-capacity transmission system for controlling transmission capacity by changing the modulation multi-value number in a multi-value modulation method according to the situation of a communication line, wherein the modulation multi-value number information is the highest-order signal sequence of the transmission signal. A method for transmitting multi-valued modulation multi-valued information, which is characterized in that it is inserted inside and transmitted.
【請求項3】 請求項1または請求項2に記載の変調多
値数情報伝送方法において、 伝送信号を多値変調方式に応じてシリアル−パラレル変
換し、生成された複数の信号系列ごとにフレーム生成す
る際に、最上位または所定の信号系列に変調多値数情報
を挿入することを特徴とする変調多値数情報伝送方法。
3. The modulated multilevel information transmission method according to claim 1, wherein the transmission signal is serial-parallel converted according to a multilevel modulation method, and a frame is generated for each of a plurality of generated signal sequences. A modulation multi-level number information transmission method, characterized in that, when generating, the modulation multi-level number information is inserted into the highest level or a predetermined signal sequence.
JP05920894A 1994-03-29 1994-03-29 Modulation multi-level information transmission method Expired - Fee Related JP3301462B2 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007336502A (en) * 2006-06-19 2007-12-27 Ntt Docomo Inc Transmission parameter change control method and wireless base station
JP2012239052A (en) * 2011-05-12 2012-12-06 Nec Corp Wireless communication device and wireless communication method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007336502A (en) * 2006-06-19 2007-12-27 Ntt Docomo Inc Transmission parameter change control method and wireless base station
JP2012239052A (en) * 2011-05-12 2012-12-06 Nec Corp Wireless communication device and wireless communication method

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