DE2225426A1 - ARRANGEMENT OF THE GENERATION OF CARRIER FREQUENCIES AND THE CONTROL OF THE FREQUENCY ACCURACY OF THE TRANSMITTED SIGNALS FOR THE TRANSMISSION OF COMBINED INFORMATION, IN PARTICULAR ABOUT HIGH VOLTAGE OVERHEAD LINES WITH CARRIER FREQUENCIES - Google Patents

Description

D ';; - tricj'uc- riaiid

Or.-1, -, g. Feces "g

- Di ^ i.-inc ,. Bergan Our file: 27 498 May 24, 1972

DUSSELDORF.

Cecillenallee 76. /./. /.Ό Η Δ.Ό

ISICRA-ZAVOD ZA AVTOMATIZACIJO ν Zdruzenem podjetju Iskra Kranj,

IJTJBLJANA / Yugoslavia

Arranging the generation of carrier frequencies and controlling the frequency accuracy of the transmitted Signals for the transmission of combined information, in particular via high-voltage overhead lines with carrier frequencies with single sideband transmission for. Bidirectional traffic on canals that stick together

The subject of the invention is an arrangement of the generation of carrier frequencies and the control of the frequency accuracy the transmitted signals for the transmission of combined information, namely conversation and telemechanics, by means of carrier frequencies, in particular over high-voltage overhead lines in such a way that in every transmitting station all required frequencies a single known precision frequency generator and in the case of bidirectional transmission, two adjacent channels are used, which are polarized in this way are that the higher! frequencies at the merger of the two channels come to rest.

For the transmission of information via high-voltage overhead lines, amplitude modulation with kinematic sideband transmission is predominantly used. For this purpose, a high frequency range of approximately 40 to 440 kHz is available, with two frequency bands being available for transmission between different stations connected to the power network in one direction and the other in the opposite direction. For such a single sideband transmission of the information in the high frequency range mentioned, at least two modulations are required to move the primary low frequency channel of 4 kHz (actually from 500 to 3720 Hz) out of its natural position

309808 / 1U1

-ί-

I 222F.426

according to desire to be able to convert anywhere in the anticipated high-frequency range, or to move the low-frequency channel from the HF range back to its natural position using an analog process using two demodulations. / ¹ The usual modulators and demodulators, which are fed from carrier frequency generators of corresponding frequencies, are used for the two modulations or demodulations required for this.

For the mentioned two modulations and deruodulations we want to agree on the following expressions and terms:

The fodulator for the first transmission modulation is to be called the channel transmission modulator, which is fed from the generator Sl _{Q of the carrier frequency fiX.}

The modulator for the second transmission modulation is to be a line transmission modulator, which consists of the generator Xl ^ dor the carrier frequency ίΛ. fed is called.

The line receiving demodulator is fed from the generator • Λο the carrier frequency fii _2. -

The channel receiving de-modulator is fed from the generator ^ of the carrier frequency --ft- '(in the case of a "reduced carrier"). In the "sovereign carrier" system, the channel demodulator is fed from the same carrier frequency generator JX ₀ as the channel modulator.

For the individual bidirectional connections for the transmission of information, a channel and line transmission modulator as well as a line and channel reception demodulator are available in both indications, for which the carrier frequencies fJI _Q , f-fl. ^, ΊΛ> 2 be and f fl- _os required.

Two arrangements for the generation of carrier frequencies are known, which differ in where it comes from Signal for the generator Π the carrier frequency fA for the

OS OS

Line receiving demodulator is obtained.

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3 2225496

The arrangement with "sovereign carrier frequencies used for feeding the channel sensor modulator and dec j.-anal-3nipfanr, sderaoäulators the same generator Λ., And. Also contains two independent crystal-controlled generators SL and IV, all of which have such a good frequency operation must be that the sum of the frequency errors of all four generators that contribute to the transmission of the information in a sighting of the connection, that is Λ and Λ in the 3-end section of one device, as well as Λ-> and SL _r _ in the receiving section of the second device permissible frequency ^{error 1 of} the transmission signals of the basic channel does not exceed.

In the case of the arrangement with "reduced carrier frequencies ¹¹ , the greatest disadvantage is that rinn has to transmit an additional signal for the transmission of the information via the overhead line, namely the signal of the reduced carrier frequency, which in certain cases (abnormal conditions the overhead line or the need for reliable transmission of important information even if the automatic control has not yet been fully established) the transmission of important information is made difficult or even prevented.

Eei two known arrangements are in each terminal "odulatoren and two disassembly.: _R: odulatoren, but in the case of" carrier frequency generators and their corresponding Lristall resonant circuits for the supply of two!. Must be sovereign 'TragerfrenueriZen "extraordinarily frequency accuracy and stability required. It ₁ case of "reduced carrier frequency" is indeed such a large stability is not necessary, but v / ith an additional i'ristallfilter needed to signal the "reduced Trägerfreouenz" on the "reception se to filtering out e it.

■ 'for transferring direction in technology zuüaan.erxkleender "Dander, where the channels for both Umübungsrichtuiif / on are immediately next to each other, is the iinseiüenp. '. uid transmission with the same frequency polarization IL -'- liuiensoitig known, as shown in Fig. 2B under a) and b). Such a lolarization is particularly important during transmission

3098G8 / 11A1 BAD ORIGINAL

combined information (i.e. conversation + remote measurement) severe overhearing noticeable.

The solution according to the invention eliminates or reduces the disadvantages mentioned in that all carrier frequencies fJil, f-Ah, ίΛρ are obtained from a single quartz crystal-controlled generator. According to a further idea of the invention, this arrangement is so constructed that one can obtain in the frequency range 40 ^to 1440 kHz from one and the same basic generator any 4 kHz channel. The arrangement uses a quartz crystal controlled basic generator for the frequency of 32 kHz. This frequency is brought to 32 kHz / 2 = 4 kHz by three frequency dividers connected in series. The 4 kHz signal obtained is converted into a narrow pulse, which serves as a frequency multiplier (η χ 4) "IdHz, in order to obtain multiples of 4 kHz. With relatively simple filters, each consisting of three coils, one can use a sift out any multiple of the frequency. The third harmonic frequency, ie 3x4 kHz = 12 kHz, is the carrier frequency fil for the channel modulator and demodulator. The other multiple frequencies, ie the fourth to the seventh harmonic (16, 20, 24, 28 kHz), are used to generate the carrier frequencies fA and in · additional modulators.

For this purpose, the 32 kHz signal is multiplied in the multiplier and the auxiliary frequencies f <u and £ co are filtered out, which represent one of the multiple frequencies of 32 kHz, ie (η χ 32) kHz and are used as auxiliary and carrier frequency generators < * L and LJ ~ feed the ring modulators together with one of the frequencies 16, 20, 24 or 28 IcHz, whereby the sum and the difference of both frequencies is obtained. The desired frequencies fA and fA .. are filtered out by appropriate filters in order to be used as carrier frequency generators.il ,. and / I ^ to feed the line modulator and demodulator.

, Instead of three quartz crystal controlled oscillators in each apparatus, two of which are for the carrier frequencies

309808/1 VA1

f-

. executed for the corresponding channel in the high frequency range have to be, we only have a quartz crystal controlled oscillator that works regardless of the Transition channel is always the same, namely for the frequency of 32 kHz, which is an advantage for the production (the same Crystal for all apparatus) as well as for entertainment (a crystal or a quartz crystal controlled oscillator as common reserve for all apparatus e, ·.). Since the frequency error in signal transmission only depends on the frequency accuracy a single oscillator is dependent, it is economically justified to choose such a design with which one achieves the greatest possible stability or frequency stability. An extremely important property of the invention Arrangement in which all carrier frequencies are obtained from one oscillator, however, lies in the fact that the frequency error is the same for both transmission directions. It follows, that the frequency control is sufficient for one direction (for which the auxiliary signal F with the frequency (η χ 4 ·) IcHz is used). That means that you can get all connections coming from a node Regarding frequency accuracy can control and also adjust from the mentioned node, without being forced to find the other end of the lines with their equipment to have to.

Another idea of the invention is based on the fact that which was determined by investigations that - namely at oppositely directed polarization of the transmission channels lying next to one another with a width of 4 kHz for combined transmission of conversation and remote measurement in the Ginne of FIG. 2A with single sideband transmission, the overhearing from the transmitter into the receiver (this is the so-called para-listening) because of the non-linearity the built-in quadrupole is smaller than in all three polarization cases according to FIG. 2B. This difference in favor the polarization case of FIG. 2A was determined by the ratio of the conversation level to the level of one of the signals in the telemetry channel certainly.

309808/1141

Hit consideration for the weaker para-overhearing can the two channels via a common filter on the transmission line connect. Due to the double width of the deo passband, the losses in the! Filter are smaller and the Sensitivity to linear distortion also gets smaller.

The other advantages and details of the inventive Arrangements are from the description of the exemplary embodiment can be seen on the basis of the accompanying drawing. It shows:

SPig. 1 a frequency plan of the channels for transmission the information in a range from 40 to 44G kHz;

2A shows a frequency plan of two channels in normal or shifted execution with mutually directed polarization of the two frequency bands;

2B shows the frequency plans of two / one channels with three other types of polarization; ~

3 shows a block diagram of the arrangement for the generation the carrier frequencies for the transmission of information;

4 shows the course of the generation of carrier frequencies in the arrangement according to the invention;

Fig. 5 shows an example of the modulation of carrier frequencies and the allocation of carrier frequencies in normal and shifted execution of the inventive arrangement.

The arrangement of the generation of carrier frequencies for the transmission of spoken information over high voltage ::; - overhead lines by means of the transmission of a Sinseitenbandec is based on the inventive idea that all are necessary Carrier frequencies f-fL, fA and filp from a single ouar · ..-, - crystal-controlled Oscillator that works for all apparatus at the same time is identical regardless of which channel they used is obtained. The channels have a width of 4 kK :: and their distribution in the high frequency range from 40 to 440 ic! ζ i.; t

309808 / 1U1

changed according to input

received5n on ... ^. «.. ΓΙλ.λ ... 9 9 9 R / 9 R

shown in the frequency plan of FIG. On this frequency plan are the frequencies "starting with 40 IdIζ and around each." 4 MIz ascending, registered. The frequency values are indicated 40, 60, 80 etc. to 440 ItTTz. On the line n that the Frequency lines that intersect at right angles are the ongoing ones Take care of the channels inscribed, starting with the No. 1, for the channel from 4 to 8 kHz, so that i: r. the aforementioned high frequency area the first channel from 40 to 44 kHz with the number 10 and the last (from 436 to "44C kHz) with the sorrow is designated.

For the individual connections, neighboring channels are used for both call directions. In the normal version (designation "N") the first pair combines the channels 10 and 11, whereby the frequency of 44 MIz is used as the carrier frequency, - in this way fifty possible connections - numbered 1, 2,. 3. · .., 50-designated are obtained. The shifted version with the designation "P" starts with channels 11 and 12, whereby the carrier frequency F between the two channels is the frequency of 43 käz. 2 ', 3 ¹ . In this case, the term "remote" channels (designation "R") is used in which four alternatives are possible with regard to the mutual polarization of the frequency channels, which are shown in the left part of FIG. 1 and denoted by a, b, c, d are.

2A shows the frequency diagram of a bidirectional link in normal "N" or shifted execution ("P"). In the latter case is the distance between the frequency bands of the two canals much larger. Lie connection X consists of two adjacent channels η and (n + 1) and recorded in Gruizwi SOCC "Hz = 8 kHz. The transmitted call frequencies bese ^ sr.

SAD OfKGJNAIL

09808/1141

in both channels the frequencies from 0.3 to 5.7 kHz. In the middle between the two channels is the frequency "?

the,, ,

is transferred from an apparatus that is used for control- *. gänglicher is, as a ILontrollsignal for TJberwachung "the accuracy of the carrier frequency and manner of their engagement £ _f '". ~

The block scheme of an arrangement of the generation "carrier * frequencies according to the invention is shown in FIG. 3 shown. quartz-controlled crystal oscillator 0 10 generates the frequency ν

32 kHz, which is divided into three successive frequency dividers into 16, 8 and finally 4 kHz. The 4 kHz signal is formed into a narrow pulse and multiplied in this way so that a mixture of the frequency multiples (η χ 4) kHz (with η = 1, 2, 3. ··) is obtained. The frequency of 32 klfz is also formed into a narrow pulse, so that a Q® mix of the frequency multiples (η χ 32) kHz is obtained in the multiplier *

From the mixture of the 4 kHz frequency multiples, the frequency of 12 kHz = fi ^ is sifted out with the filter F 10, the to feed the channel modulator and ICanaldemodulator det is, while with the filters F 11 and F 12 ge a voü Frequencies 16, 20, 24 and 28 IcHz is screened out. Hit the tern F 13 and F 14 is the required frequency multiple of 32 kHz for fu>. and-fwu sifted out.

This is to be explained with the aid of FIG. The hairy lower carrier frequencies, which are multiples of 4 kHz, can be expressed as the sum (n - 1) 32 + 28 or 24 or 20 and η further as the difference η χ 32 - 1-6 or 20, 24, 28 obtained after which the next lower multiple of 32 kHz, that is "^ (n - 1) 32 IcHz, follows. In this way, 'any carrier frequency'. ' £ SL ^ and f / I _{2 can be obtained} as the sum or difference of a certain multiple of 32 IcHz and a multiple of 4 IcIIz.

BATH

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222R426

If one now refers back to FIG. 3, then the output of the filter F 13 becomes at the frequency fui. as well as the output of one of the filters F "11 or F 12 -sum ring modulator M 11, from whose output the required carrier frequency fAj is filtered out with the filter F 16 and appropriately amplified with the amplifier 0.15. The output of the filter is analogous F 14 · with the frequency fu ^ and the output of the second filter from the group F 11, F 12 to the ring modulator M 15, from the output of which with the filter F 15 the carrier frequency / £. (L · filtered out and in the amplifier 0 14 · accordingly amplified v / ird, directed.

4 shows the entire frequency response in the arrangement according to the invention for generating the carrier frequencies. The frequency of 32 kHz, which is converted to 4 kHz in the frequency dividers 32/4, is generated in the quartz crystal controlled oscillator 0 10 v / ird. In the multiplier 0 12, which is combined with an amplifier, the multiples of the frequency 4 kHz are obtained and in a similar multiplier Ό 13 the multiples of the frequency 32 kHz are obtained. By modulating the corresponding multiples of 32 ItHz and 4 kHz in the ring modulators 1 ″, 11 and M 15, the desired carrier frequencies for the two transmission channels are obtained.

The information with frequencies from 0.3 to 3 »72 kHz are polarized in the two transmission channels in such a way that the frequencies in both channels increase to the point of contact of the channels. That's exactly in the hut between the two canals Auxiliary signal F, from the end station to the start station for the purpose Control of the frequency error is transmitted. Y / ie already mentioned, In the arrangement according to the invention, the frequency error is the same in both directions, so that it is sufficient to determine the frequency error when transmitting in one direction · to measure around the to be able to determine whole frequency errors. So it is very convenient to select a node of the connections for the control, where you can control all the connections that come together in the node without the stations at the other linden of the front

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having to seek out ties. :.: With the same signal F, any alarm from the remote station is also transmitted and the failure of the signal F is indicated.

BATH ORIGINAL 309808 / 11A1

Claims (1)

7225426 Claim Arrangement of the generation of C-rägerfreouenzen and the I. control of the frequency accuracy of the transmitted signals door the transmission of combined information, in particular over high voltage overhead lines with carrier frequencies with single sideband transmission for Zv / one-way traffic on ancaiue-sticking Channels, composed of per se known egg. ments, ie quartz crystal controlled generator C 10, frequency multiplexer 0 12, 0 15, frequency dividers 52/4, frequency filters F 10 to F 16, ring modulators M 11, Ι.Ί 15 and amplifiers 0 14, C 15 »characterized in that each Terminal of the connection with Zv / directional traffic with a ■ single <crystal-controlled generator (0 10) for one Frequency of 52 kHz is equipped, at its output on the one hand a frequency multiplier (0 15) for frequency multiples of | 2 kHz and on the other hand three connected in series Frequency divider (52/4) for generating a frequency of 4 fcHl rait cascaded frequency multiplier for frequency multiples (G 12) of 4 IcHz are connected; that on Friday (O 12) for 4 IcHz a 12 kHz filter (F 10) for di @ (carrier frequency (fQ.) of the channel modulator and demodulator Möwie two filters (F 11 and F 12) for a frequency of 16, 2C, 24 or 28 kHz each for connection to a ring modulator (I. '11, i: 15) i while on the frequency multiplier (0 15) for yd ^: \ ύ \ ζ two filters (F 13, F 14) for filtering out one auxiliary frequency each (ft ** ,, and ft »^,) for connection to one already erv / wires RIn, ^ - nioäuiator (M 11 and 1 '15) screened for generating the carrier frequencies CfAj ^"iJ ^) v ^d ie in each case by a filter (F 15, F 15) and each by an amplifier (0 14, C 15) fed to the output v / ground, connected; that the adjacent additional transmission channels are polarized in opposite directions with the information frequencies, so that the higher Inrorrcaticnsfreouenzen are closer to your point of contact of the channels and that 87114 1 ^BAÖ Help signal (F) for checking the frequency accuracy the transmission and for the alarm transmission due to the failure this signal lies in the middle between the two channels. 309808/1 U1