SU377972A1 - DESCRIPTION OF THE INVENTION - Google Patents

Description

one

There is a known method of transmitting discrete information with relative phase manipulation with several carriers and combining the Time of the subsequent parcel with the previous one.

The disadvantage of this method is the need to simultaneously transmit a number of carrier frequencies, and consequently, a reduction in the power supplied to each carrier frequency and the complexity of the circuits that convert the frequencies in the transmission and reception.

In order to use high-base codes, the proposed method transmits parcels at one of several frequencies that are in a rational relationship, where the frequency and phase of one parcel, relative to the frequency and phase of the previous parcel, determines the transmitted information, and at the reception after combining in time reproduce on the screen of the cathode-ray tube one of the Lissajous figures of the set corresponding to the alphabet of the message source.

FIG. 1 is a block diagram of the transmitting side of the BOND line illustrating the proposed method; in fig. 2 is a block diagram of the receiving side.

When applying to a cathode tube, two oscillations of the same frequency fi and f, if they are in a rational relation.

stable images are observed, the shape of which depends on the frequency ratio

 t and the angle of phase shift between them AE.

/but

Image STABILITY arises due to the presence of a repetition period T at the beating of two oscillations with frequencies in a rational relation. This period with the frequency ratio

T p

„P

where type is integers, is / - -.

ft / 1

From the relation it follows that the phase shift between oscillations at frequencies f and / 2 can be defined as

BUT

Av (p „

l

where ф1 and ф2 are the phases of oscillations at frequencies / 1 and / 2- At.

Dw P1 - D Consequently, I am AF (when transmitting neighboring parcels at one frequency), A9 (when transmitting neighboring parcels at different frequencies) H is the ratio of frequencies of neighboring parcels t, you can get a large variety of shapes

Lissajous

By assigning each letter of the Russian alphabet to its Lissajous figure, each letter can be transmitted with only one parcel, which allows a five-fold reduction in transmission time as compared to the binary code when each letter is typed out of five parcels (Bodo code).

The transfer of the proposed method is as follows.

Depending on the required code base, i.e., on the required alphabet, the number of frequencies used and the magnitude of the phase shifts between them are selected.

If the transmission is carried out in digits of the decimal number system, then the necessary value of the code is equal to ten (or the alphabet of the message source contains ten different signals).

Select the frequency ratio

A i-J L "2

Choose five values of Af. AF 0 °, 45 °, 90 °, 135 ° and 180 ° and five values of A9. , 60 °, 120 °, 180 °, 240 °.

For each of the ten digits of the alphabet, we fix a certain ratio of the frequencies and phases of the neighboring parcels or a certain Lissajous figure.

The transmission is carried out by the method of relative phase telegraphy (OFT): the carrier frequency and phase of this parcel is chosen so that when comparing it with the frequency and phase of the previous parcel, we obtain the desired Lissajous figure on the screen of the receiving electron-tube.

As with conventional OFT, each parcel carries information about the transmitted sign (selected by comparing it with the previous one) and simultaneously serves as a basic parcel for receiving a subsequent parcel, but at the beginning of a communication session, one parcel is needed, which is auxiliary for receiving the first, informational one. Then, the first parcel serves as a key for receiving a second, a second for receiving a third, and so on.

The block diagram of the transmitting side of the communication line (Fig. 1) contains a frequency generator 1, a frequency multiplier 2 into two, a phase shifter 3, a source of 4 decimal signals, a manipulator 5, and a switch 6.

Each decadele parcel entering the manipulator 5 changes its position

switch 6 according to the algorithm described above.

The manipulator circuit 5 is easily accomplished using proximity switches and logic elements.

At the receiving side (FNG. 2), each data and the previous parcel are combined in time using the delay line 7 (the delay time Tzad is equal to the duration of the elementary parcel) and is sent for comparison to

electron beam tube 8 with two pairs of control plates. Depending on the ratio of the frequencies and phases of the neighboring parcels, one of the Lissajous figures 9 is observed on the screen, corresponding to one or another decimal digit.

Subject invention

A method of transmitting discrete information with relative phase manipulation with several carriers and combining in time the subsequent parcel with the previous one, characterized in that, with the purpose of using PIA codes with high drops, the parcels are transmitted at one of several frequencies that are in a rational ratio, and and the phase of one parcel, with respect to the frequency and phase of the previous burst, determines the transmitted information, and at the reception, after combining in time, is reproduced on the screen of the cathode ray tube and Lissajous figures set corresponding to the source of the messages alphabetically.