JPS5986945A - Data transmitting modem - Google Patents
Data transmitting modemInfo
- Publication number
- JPS5986945A JPS5986945A JP57198109A JP19810982A JPS5986945A JP S5986945 A JPS5986945 A JP S5986945A JP 57198109 A JP57198109 A JP 57198109A JP 19810982 A JP19810982 A JP 19810982A JP S5986945 A JPS5986945 A JP S5986945A
- Authority
- JP
- Japan
- Prior art keywords
- output
- data
- band
- frequency
- multiplier
- 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
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/32—Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は多重データ伝送用度調器及び復調器に関するも
のである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to modulators and demodulators for multiplex data transmission.
従来例の、構成とその問題点
近年、情報化社会の要請により有線無線を問わずデータ
伝送ネットワークが急速に発展して来ており、多くの種
類のデータを効率良く伝送する事が必要となって来た。Conventional configurations and their problems In recent years, data transmission networks, both wired and wireless, have been rapidly developing due to the demands of the information society, and it has become necessary to efficiently transmit many types of data. I came.
例えば同軸ケーブルを使用するデータ回線では、同軸ケ
ープＩしの帯域によりチャネル数が制限される。また無
線の場合には割りあて帯域によりチャネル数が制限され
る。更にチャネル数が増加すると、受信側ではその数だ
け帯域Ｐ波器が必要となる。よって、データ伝送用変復
調器としては構成が簡単で、周波数効率（ｂｉｔ／Ｈｚ
）がよく、雑音に強いものが望まれる。For example, in a data line using a coaxial cable, the number of channels is limited by the band of the coaxial cable. Furthermore, in the case of wireless communication, the number of channels is limited by the allocated band. If the number of channels further increases, the number of band P-wave devices corresponding to that number will be required on the receiving side. Therefore, as a data transmission modulator/demodulator, the configuration is simple and the frequency efficiency (bit/Hz
) and is resistant to noise.
次に、従来から使用されている変復調器について第１図
（ａ） ＜ｂ）を用いて説明する。２相位相変調器の一
例を第１図に示す。第１１１（ａ）は２相位相変調器、
第１図（ｂ）は２相復調器であり、（１）は低域；Ｐ波
器、（２）α０は掛算器、（３）は搬送波発振器、（４
） （５） （７）は帯域ろ波器、ζ６）は２乗器、（
６）はＰＬＬ 、 （９）は分局器、（ロ）は低域Ｐ波
器、（２）は比較器である。第１図（”）の送信側では
、データはまず低域Ｐ波器（１）でスペクトラムの高域
分を落とされ、搬送波発振器（３）からの搬送波と掛算
をされ、２相位相変調波となる。Next, a conventionally used modulator/demodulator will be explained using FIG. 1(a) <b). An example of a two-phase phase modulator is shown in FIG. No. 111(a) is a two-phase phase modulator;
Figure 1(b) shows a two-phase demodulator, where (1) is a low-frequency P-wave unit, (2) α0 is a multiplier, (3) is a carrier wave oscillator, and (4) is a multiplier.
) (5) (7) is a bandpass filter, ζ6) is a squarer, (
6) is a PLL, (9) is a branching unit, (b) is a low-frequency P-wave device, and (2) is a comparator. On the transmitting side of Figure 1 (''), the data is first filtered out by the low-band P-wave generator (1), which drops the high-frequency part of the spectrum, and then multiplied by the carrier wave from the carrier wave oscillator (3), which generates a two-phase phase modulated wave. becomes.
この変調波は帯域Ｐ波器（４）により帯域制限され、次
に伝送路に出力される。実際の掛算器が理想的でない為
低域Ｐ波器（１）及び帯域Ｐ波器（４）が必要である。This modulated wave is band-limited by a band P-wave device (4) and then output to a transmission path. Since the actual multiplier is not ideal, a low-band P-wave generator (1) and a band P-wave generator (4) are required.
第１図（ｂ）の受信側では、受信変調波は帯域Ｐ波器（
５）により選択され、２乗器（６）、帯域Ｐ波器（７）
、ＰＬＬ （ｓ）、分局器（９）により搬送波が再生さ
れ、この再生搬送波と変調入力波は掛算器αＱによって
掛算され、低域Ｐ波器αη、比較器（２）を通す事に誹
りデータが再生される。位相変調は相の数を増す毎に周
波数効率がＬがるが回路規模もより複雑になる。On the receiving side in Fig. 1(b), the received modulated wave is transmitted by a band P-wave filter (
5), squarer (6), band P-wave generator (7)
, PLL (s), the carrier wave is regenerated by the splitter (9), this regenerated carrier wave and the modulated input wave are multiplied by the multiplier αQ, and the slandered data is passed through the low-frequency P-wave unit αη and the comparator (2). is played. In phase modulation, the frequency efficiency decreases as the number of phases increases, but the circuit scale also becomes more complex.
位相変調方式はりｋと誤り率の関係が振幅変調方式より
すぐれており、また搬送周波数を適当に選ぶ事により周
波数多重化が可能である。しかし、チャネル数が増すと
、送受信側の帯域Ｐ波器（４） （５）もチャネルの数
だけ必要となり、チャネル間隔が狭くなると、帯域Ｐ波
器の実現も困難になる。伝送路の帯域は有限である為、
帯域沖波器の実現の困難度、データレートによりチャネ
ル数（幅）が決められる。The phase modulation method has a better relationship between beam k and error rate than the amplitude modulation method, and frequency multiplexing is possible by appropriately selecting the carrier frequency. However, as the number of channels increases, the number of band P-wave devices (4) and (5) on the transmitting and receiving sides becomes equal to the number of channels, and as the channel spacing becomes narrower, it becomes difficult to realize a band P-wave device. Since the bandwidth of the transmission path is limited,
The number of channels (width) is determined by the degree of difficulty in realizing a band-pass transducer and the data rate.
一方周波数変調方式もデータ伝送にしばしば使用される
が、多重化の場合には前記位相変調方式と同様多重化の
数だけ送受信帯域Ｐ波器が必要となる。これが装置全体
のコスト高の大きな要因になっている。On the other hand, the frequency modulation method is often used for data transmission, but in the case of multiplexing, as in the case of the phase modulation method, as many transmitting/receiving band P-wave devices as there are for multiplexing are required. This is a major factor contributing to the high cost of the entire device.
発明の目的
本発明は以を述べた従来例の欠点を除去し、受信Ｐ波器
を従来の半数ですませ、従来と同等の特性を持つデータ
伝送変復調装置を実現することを目的とするものである
。Purpose of the Invention The object of the present invention is to eliminate the drawbacks of the conventional example described below, reduce the number of receiving P-wave devices to half of the conventional one, and realize a data transmission modulation/demodulation device having characteristics equivalent to the conventional one. be.
発明の構成
を記目的を達成するために、本発明は周波数変調器と第
１の掛算器と＠ｌの帯域Ｐ波器を含めて成るデータ伝送
変調器と、第２の帯域Ｐ波器と二乗演算器と周波数復調
器と平方根演算器と遅延回路と第２の掛算器と低域Ｐ波
器と比較器を含めて＼ 成るデータ伝送復調器とを具
備し、第１番目のデータは前記周波数変調器に入力され
、周波数変調器の出力と第２番目のデータは前記第１の
掛算器に入力され、第１の掛算器の出力は前記第１の帯
域Ｐ波器に入力され、第１の帯域Ｐ波器の出力端子はデ
ータ伝送変調器出力端子に接続され、前記データ伝送復
誓器入力端子は前記第２の帯域Ｐ波器に接続され、第２
の帯域Ｐ波器出力は前記二乗演算器と遅延回路に入力さ
れ、二乗演算器の出力は平方根演算器と周波数復調回路
に入力され、平方根演算器の出力と遅延回路の出力は掛
算器に入力され、掛算器の出力は前記低域Ｐ波器に入力
され、低域Ｐ波器の出力は比較器に入力され、第１番目
のデータと第２番目のデータを多重して伝送し、前記周
波数復調器出力に前記第１番目のデータを出力し、前記
比較器出力に前記第２番目のデータを出力するように構
成し、第１番目のデータを周波数変調器に入力して、こ
の周波数変調器の出力信号を搬送波とし、こ°れを帯域
制限された第２番目のデータにより位相変調し、伝送信
号波形（変調信号出力）の周波数と位相にそれぞれ第１
番目のデータ信号、第２番目のデータ信号を乗せること
によって、ひとつの周波数帯域により２チヤネルのデー
タを同時に伝送可能としたものである。DETAILED DESCRIPTION OF THE INVENTION To achieve the object, the present invention provides a data transmission modulator including a frequency modulator, a first multiplier, and a @l band P-wave device, and a second band P-wave device. It is equipped with a data transmission demodulator including a square operator, a frequency demodulator, a square root operator, a delay circuit, a second multiplier, a low-frequency P-wave unit, and a comparator, and the first data is The output of the frequency modulator and the second data are input to the first multiplier, the output of the first multiplier is input to the first band P-wave generator, and the output of the frequency modulator and the second data are input to the first multiplier. The output terminal of the first band P-wave device is connected to the data transmission modulator output terminal, the data transmission reviser input terminal is connected to the second band P-wave device, and the second
The output of the band P-wave device is input to the square operator and the delay circuit, the output of the square operator is input to the square root operator and the frequency demodulation circuit, and the output of the square root operator and the output of the delay circuit are input to the multiplier. The output of the multiplier is input to the low-pass P-wave unit, and the output of the low-pass P-wave unit is input to the comparator, and the first data and the second data are multiplexed and transmitted. The first data is output to the frequency demodulator output, the second data is output to the comparator output, the first data is input to the frequency modulator, and the frequency The output signal of the modulator is used as a carrier wave, and this is phase-modulated by band-limited second data, and the frequency and phase of the transmission signal waveform (modulated signal output) are
By adding the first data signal and the second data signal, two channels of data can be transmitted simultaneously using one frequency band.
これにより、２種類のデータを側帯域で伝送した時と比
べて送受信帯域Ｐ波器の数が半分ですみ、かつ帯域幅と
しては２種類のデータ帯域の和と等しくなる為帯域Ｐ波
器の実現が非常に容易となる。As a result, the number of transmitting/receiving band P-wave devices is halved compared to when two types of data are transmitted in the side bands, and the bandwidth is equal to the sum of the two types of data bands, so the number of band P-wave devices is reduced by half. Realization becomes very easy.
実施例の説明
以下本発明の一実施例を図面に基づいて説明する。始２
図において、に）は周波数変調器、σ嗜は低域Ｐ波器、
（至）は掛算器、ＯＱ（ロ）は帯域Ｐ波器、（ト）は二
乗器、αりは周波数弁別器、■は平方根演算器、ｅηは
遅延回路、（財）は掛算器、に）は低域Ｐ波器、弼は比
較器である。送信側では第１番目のデータは周波数変調
器−に入力され、第２番目のデータは低域Ｐ波器θ◆に
入力され、上記周波数変調器（ハ）の出力と低域Ｐ波器
α◆の出力は掛算器＠に入力され、掛算器αθの出力は
帯域Ｐ波器ａｅＩにより帯域制限され、伝送路へ送出さ
れる。受信側では、まず帯域Ｐ波器ａηにより選択され
、その出力は二乗器（財）と遅延回路Ｑ０に入力される
。二乗器（７）の出力は周波数弁別器αりと平方根演算
器（イ）べ入力される。を記周波数弁別器α呻により第
１番目のデータが再生される。また、を記遅延回路Ｑカ
と平方根演算器曽の出力は掛算器（イ）に入力され、掛
算器に）の出力は低域−波器−、比Ｖ器（ハ）に入力さ
れる。比較器（ハ）の出力が第２番目の再生データであ
る。DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. beginning 2
In the figure, ) is a frequency modulator, σ is a low-frequency P wave generator,
(to) is a multiplier, OQ (b) is a band P-wave unit, (g) is a squarer, α is a frequency discriminator, ■ is a square root operator, eη is a delay circuit, (goods) is a multiplier, ) is a low-frequency P-wave device, and 弼 is a comparator. On the transmitting side, the first data is input to the frequency modulator -, the second data is input to the low-band P-wave generator θ◆, and the output of the frequency modulator (c) and the low-band P-wave generator α The output of ◆ is input to the multiplier @, and the output of the multiplier αθ is band-limited by the band P-wave unit aeI and sent to the transmission path. On the receiving side, the signal is first selected by a band P wave generator aη, and its output is input to a squarer and a delay circuit Q0. The output of the squarer (7) is input to the frequency discriminator (alpha) and the square root calculator (a). The first data is reproduced by the frequency discriminator α. In addition, the outputs of the delay circuit Q and the square root calculator are input to a multiplier (A), and the outputs of the multiplier are input to a low-frequency waveformer and a ratio V unit (C). The output of the comparator (c) is the second reproduction data.
第３図（ａ） ’ｂ） （Ｃ）に第１番目と第２番目の
データ信号および掛算器（至）の出力時間軸信号を示す
。第１低域Ｐ波器α◆の出力波形をｓ ’ （ｔ）とす
ると、第２図（Ｂ）の出力信号ｇ （ｔ）は（１）式の
様に表わす事ができる。FIG. 3(a)'b)(C) shows the first and second data signals and the output time axis signal of the multiplier (to). Assuming that the output waveform of the first low-pass P-wave device α◆ is s' (t), the output signal g (t) in FIG. 2(B) can be expressed as in equation (1).
ｇ（ｔ） ＝ ａｓ’（ｔ） ｃｏｓ （ｒ（ｔ） −
ｔ Ｊ −−−−・・−・・（１）ここでａは
定数である５ ｇ’（ｔ）は１又は−１の値のみを取る
から（１）式は（ｌｆ式の様に書く事ができる。g(t) = as'(t) cos (r(t) −
t J ------・・・・(1) Here, a is a constant 5 g'(t) takes only the value of 1 or -1, so equation (1) can be written as (lf equation) I can do things.
ｇ（ｔ） −ａ ｃｏｓ （ｒ（ｔ）ｔ＋φ（ｔ）Ｊ
−曲・＜１）′π ｓ’（ｔ） ＝ −１
（１）′式の信号が伝送路を通り受信器に入力される。g(t) −a cos (r(t)t+φ(t)J
-Song・<1)'π s'(t) = -1 A signal of the formula (1)' is input to the receiver through the transmission path.
二乗器（至）の出力ｘ （ｔ）は
ｘ（ｔ）＝ ［ｇ（ｔ））２ ＝ ａ２ｃｏｓ”
（ｒ（ｔ）−ｔ 十−（ｔ） ）−（２）２
＝ 、 （、ｃｏｓ ［２ｒ（ｔ）・ｔ ＋２１１（を
月＋１］の様になる。φ（１）は０又はπであるから、
二乗する事により位相情報ｓ （ｔ）がなくなり、周波
数変調器０の出力波形を二乗した波形になっている。（
２）式の波形を周波数弁別器−に通す事により８（ｔ）
を再生する事ができる。一方、（２）式の２巣器（至）
の出力は平方根演算器に）により（３）式の様になる。The output x (t) of the squarer (to) is x(t) = [g(t))2 = a2cos”
(r(t)-t 10-(t))-(2)2 = , (, cos [2r(t)・t+211(month+1]). φ(1) is 0 or π. because there is,
By squaring, phase information s (t) is eliminated, and the waveform becomes the square of the output waveform of frequency modulator 0. (
2) By passing the waveform of the equation through a frequency discriminator -8(t)
can be played. On the other hand, the two nests (to) of equation (2)
The output of is given by the square root calculator) as shown in equation (3).
ｙ（ｔ）＝ ｅｏｓ （ｒ（ｔ） −ｔ ）
＝−−曲−（３）よって掛算器に）の出力ｚ （ｔ
３は（４）式の様になる。y(t)=eos(r(t)−t)
=−−song−(3) Therefore, to the multiplier) output z (t
3 becomes as shown in equation (4).
ｚ（ｔ） ＝ ｇ（ｔ） ｘ ｙ（ｔ）＝ ａｓ’（ｔ
）ｃｏｓ ［ｒ（ｔ） ・ｃ ）ｘ ｃｏｓ （ｒ（ｔ
）−ｔ ）＝ −ａｓ’（ｔ） （ｃｏｓ （２ｒ（ｔ
）−ｔ ） ＋ １ ） ＝１４）ここでｇ’（ｔ）は
遅延回路出力である。このｚ（ｔ）を低域Ｐ波器（イ）
を通す事により（４）式の第２項のみを抜き出し、比較
器（ハ）によりｓ （ｔ）を再生する事ができる。遅延
回路ψρは掛算器（財）に入力されるｇ’ （ｔ）とｙ
（１）の位相を合わせる為のものである。z(t) = g(t) x y(t) = as'(t
)cos [r(t) ・c )x cos(r(t)
)-t )=-as'(t) (cos (2r(t
)-t) + 1) = 14) where g'(t) is the delay circuit output. This z(t) is converted into a low-frequency P wave generator (a)
By passing , only the second term of equation (4) can be extracted, and s (t) can be reproduced by the comparator (c). The delay circuit ψρ is input to the multiplier (goods) g' (t) and y
This is to match the phase of (1).
以上述べた様に、本データ変復調装置は、２種類のデー
タ信号を周波数多重して体数する従来例と比較して、２
種のデータ信号を連続な一つの帯域幅で送る事ができ、
従って送・受信帯域Ｐ波器はそれぞれひとつで済みかつ
周波数多重して伝送した時の受信帯域Ｐ波器よりも帯域
幅が広くなる為Ｐ波器を実現しやすく、更に位相変調・
周波数変調と同じ耐雑音性を持ち、また定振幅であるた
め非線形回線（例えば衛生通信に使用されるＴｈＴ等）
にも強い。As mentioned above, this data modulation/demodulation device has two
can send different data signals in one continuous bandwidth,
Therefore, only one transmitting and receiving band P-wave device is required, and the bandwidth is wider than that of the receiving band P-wave device when transmitting by frequency multiplexing, making it easier to realize a P-wave device.
It has the same noise resistance as frequency modulation and has constant amplitude, so it is suitable for nonlinear lines (such as ThT used in satellite communications).
It is also strong.
発明の効果
以を本発明によれば、周波数効率がよく、しかも構成が
簡単で、１雑音性がある大きな効果を有する。Effects of the Invention According to the present invention, the present invention has great effects such as good frequency efficiency, simple structure, and low noise.
第１図（ａ） （ｂ）は従来のデータ伝送変復調装置の
回路構成図、第２図（ａ） （ｂ）は本発明の一実施例
を示す回路構成図、第８図は本発明による信号時間軸波
形図である。
０・・・周波数変調器、α４■・・−低域Ｐ波器、Ｑｌ
ｌに）・・・掛算器、ＤＩ （１７１・・・帯域Ｐ波器
、０樽・・・二乗器、α佛・・・周波数弁別器、に）・
・・平方根演算器、（ハ）・・・遅延回路、（ハ）・・
・比較器
代理人 森 本 義 弘第２図
（ａ）
第３図
出力FIGS. 1(a) and (b) are circuit configuration diagrams of a conventional data transmission modulation/demodulation device, FIGS. 2(a) and (b) are circuit configuration diagrams showing an embodiment of the present invention, and FIG. 8 is a circuit configuration diagram according to the present invention. FIG. 3 is a signal time axis waveform diagram. 0...Frequency modulator, α4■...-Low frequency P wave device, Ql
l)...multiplier, DI (171...band P wave unit, 0 barrel...squarer, α Buddha...frequency discriminator, etc.)
...square root calculator, (c)...delay circuit, (c)...
・Comparator agent Yoshihiro Morimoto Figure 2 (a) Figure 3 output
Claims (1)
含めて成るデータ伝送変調器と、嫡２の帯域Ｐ波器と二
乗演算器と周波数復調器と平方根演算器と遅延回路と第
２の掛算器と低域Ｐ波器と比較器を含めて成るデータ伝
送復調器とを具備し、第１＃目のデータは前記周波数変
調器に入力され、周波数変調器の出力と第２番目のデー
タは前記第１の掛算器に入力され、第１の掛算器の出力
は前記第１の帯域Ｐ波器に入力され、＠１の帯域Ｐ波器
の出力端子はデータ伝送変調器出力端子に接続され、前
記データ伝送復調器入力端子は前記第２の帯域Ｐ波器に
接続され、＠２の帯域Ｐ波器出力は前記二乗演算器と遅
延回路に入力され、二乗演算器の出力は平方根演算器と
周波数復調回路に入力され、・平方根演算器の出力と遅
延１路の出力は掛算器に入力され、掛算器の出力は前記
低域Ｐ波器に入力され、低域ろ波−器の出力は比較器に
入力され、第１番目のデータと第２番目のデータを多重
して伝送し、前記周波数復調器出力に前記第１番目のデ
ータを出力し、前記比較器出力に前記第２番目のデータ
を出力するようにしたデータ伝送変復調装置。1. A data transmission modulator including a frequency modulator, a first multiplier, a first band P-wave unit, a second band P-wave unit, a square operator, a frequency demodulator, a square root operator, and a delay. a data transmission demodulator including a circuit, a second multiplier, a low-frequency P-wave unit, and a comparator, the #1 data is input to the frequency modulator, and the output of the frequency modulator and The second data is input to the first multiplier, the output of the first multiplier is input to the first band P-wave device, and the output terminal of the @1 band P-wave device is used for data transmission modulation. The data transmission demodulator input terminal is connected to the second band P-wave device, and the @2 band P-wave device output is input to the square calculator and the delay circuit, and the data transmission demodulator input terminal is connected to the second band P-wave device. The output of the square root calculator and the output of the delay circuit are input to the multiplier, and the output of the multiplier is input to the low-frequency P-wave generator, The output of the filter is input to a comparator, the first data and the second data are multiplexed and transmitted, the first data is output to the frequency demodulator output, and the comparator A data transmission modulation/demodulation device configured to output the second data as an output.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198109A JPS5986945A (en) | 1982-11-10 | 1982-11-10 | Data transmitting modem |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198109A JPS5986945A (en) | 1982-11-10 | 1982-11-10 | Data transmitting modem |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5986945A true JPS5986945A (en) | 1984-05-19 |
Family
ID=16385624
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57198109A Pending JPS5986945A (en) | 1982-11-10 | 1982-11-10 | Data transmitting modem |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5986945A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20040076501A (en) * | 2003-02-26 | 2004-09-01 | 학교법인 한양학원 | Method and Device for performing PSK-modulation using pulse for communications |
| EP1571817A1 (en) * | 2004-03-02 | 2005-09-07 | Mindspeed Technologies, Inc. | Modem signal detection in a gateway |
-
1982
- 1982-11-10 JP JP57198109A patent/JPS5986945A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20040076501A (en) * | 2003-02-26 | 2004-09-01 | 학교법인 한양학원 | Method and Device for performing PSK-modulation using pulse for communications |
| EP1571817A1 (en) * | 2004-03-02 | 2005-09-07 | Mindspeed Technologies, Inc. | Modem signal detection in a gateway |
| US7411941B2 (en) | 2004-03-02 | 2008-08-12 | Mindspeed Technologies, Inc. | Text telephone modem communications over packet networks |
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