RU2460211C1 - Method of transmitting information signals and apparatus for realising said method - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: information unit of five pulses is encoded in form of a sequence of one positive pulse, one positive pulse magnified N times, one positive pulse, one negative pulse and one positive pulse, and an information zero of five pulses is encoded in form of a sequence of one negative pulse, one negative pulse magnified N times, one negative pulse, one positive pulse and one negative pulse; the obtained sequences are transmitted to a data transmission medium, and at the receiving side, the received signal is compared with reference signals through cross-correlation. At the transmitting side, the apparatus includes an amplifier whose input is connected to a stage which generates the second pulse of the five-pulse signal, the output is connected to an adder, and at the receiving side, there is a similar amplifier whose input is connected to the output of a delay line, corresponding to the second pulse of the five-pulse signal, the output of the amplifier is connected to an adder.

EFFECT: improved noise immunity.

2 cl, 9 dwg

Description

The invention relates to methods for encoding, decoding and code conversion for error detection and correction, namely, to improve noise immunity.

A known method of encoding using Barker sequences (Theory of electrical communications. A textbook for higher education institutions under the editorship of Prof. D. D. Klovsky - M .: Radio and communications, 1998 - S.362-365), including the encoding of an information unit and zero a three- and five-element sequence with the subsequent transfer of these sequences to the data transmission medium. The received signals are compared with the reference intercorrelation path, the signal acceptance is made from the intercorrelation function, the received signal is evaluated based on the ratio of the main peak and side lobes in the cross correlation function.

The disadvantage of this method is the inability to detect an information signal with a high level of interference.

The agreed filter is known (Theory of electrical communications. A textbook for higher education institutions under the editorship of Prof. D. D. Klovsky - M .: Radio and communications, 1998 - S.362-365), which includes a delay line, phase-saving and phase-inverting cascades summing device. The disadvantage of this device is the inability to detect an information signal with a high level of interference.

The aim of the invention is to obtain a clear signal with a high level of interference.

This goal is achieved by the fact that pulses with doubled (or N) energy level are introduced into the Barker sequence.

The invention according to claim 1 is that the coding of an information unit of five pulses is performed in the form of a sequence of one positive, N times increased one positive, one positive, one negative and one positive pulses, and the coding of information zero of five pulses is performed in in the form of a sequence of one negative, increased N times one negative, one negative, one positive and one negative impulses, and N before is any positive number greater than unity, the received sequences are transmitted to the data transmission medium, and on the receiving side, the received signal is compared with the standard way of their correlation, and the essence of the invention according to p. to the cascade forming the second pulse of the five-pulse signal, the output to the summing device connected via the data transmission medium to the receiving side, and a similar one is introduced on the receiving side the same amplifier, the input of which is connected to the output of the delay line corresponding to the second pulse of the five-pulse signal, the output of the amplifier is connected to a summing device.

Figures 1 and 3 show diagrams of a method for transmitting an information unit and information zero using Barker five-element sequences; Figures 2 and 4 show the correlation functions of these sequences in the form of a main peak and side lobes.

Figure 1 shows the information unit in the form of a five-element Barker signal, consisting of four positive 1, 2, 3, 5 and one negative impulses 4, and figure 2 shows the autocorrelation function of this sequence in the form of the main peak 1 and side lobes.

Figure 3 shows the information zero in the form of a five-element Barker signal, consisting of four negative 1, 2, 3, 5 and one positive pulse 4, and figure 4 shows the autocorrelation function of this sequence in the form of the main peak 1 and side lobes.

Figure 5 shows the information unit in the form of the proposed five-element sequence, consisting of three positive 1, 3, 5, one doubled positive pulse 2 and one negative pulse 4, and Fig. 6 shows the inter-correlation function of this sequence in the form of the main peak 1 and side lobes.

Figure 7 shows the information zero in the form of the proposed five-element sequence, consisting of three negative 1, 3, 5, one doubled negative pulse 2 and one positive pulse 4, and Fig. 8 shows the inter-correlation function of this sequence in the form of the main peak 1 and side lobes.

Figure 9 presents a diagram of a device for implementing a method of transmitting information signals, including a transmitting side 6 and a receiving side 7, consisting of delay lines, respectively, 8 and 9 with phase-saving and phase-inverting cascades 10, 11, 12, 13 and 14, while an amplifier 15 is connected in the transmitting part to the cascade 13, and a similar amplifier 22 is also connected in the receiving part 7 to the same cascade 20, the outputs of the amplifiers 15 and 20 being connected to the inputs of the summing devices 16 and 23.

The proposed method of transmitting information is as follows.

On the transmitting side, the information unit and zero are encoded by a five-element signal, which is a modified Barker signal, in which the second pulse 2 has a doubled energy level (Figure 5) or a level increased by N times, and on the receiving side, the received signals are mutually correlated with the reference signals . According to the inter-correlation function, a conclusion is made about the presence or absence of the received information signal, which is determined by the ratio of the central peak 1 and the side lobes in the inter-correlation function (Fig. 6).

When the proposed sequence of pulses is mutually correlated, the difference between the central peak 1 and the side lobes is significant, and this difference is significantly larger than the increased energy of the transmitted information signal.

If we increase the energy of all pulses of the five-element Barker sequence (Figs. 1, 3), that is, the entire information signal, for example, twice, then the magnitude of the main peak (Figs. 2, 4) doubles. However, the energy consumption for transmission also doubles.

In the proposed sequence, an increase in the energy of only one pulse twice (Fig. 5, 7) leads to an increase in the main peak by 1.6 times (Fig. 6, 8), and the energy consumption for transmission increases only by 1.2 times.

The proposed device operates as follows.

On the transmitting side 6, the input signal enters the delay line 8, from which it enters the phase-saving and phase-inverting stages, where a signal is generated with pulses of the necessary positive or negative polarity. The pulse from the output 13 is supplied to the amplifier 15, then these pulses are summed in the adder 16 and sent to the data medium. On the receiving side 7, the pulses arrive at the delay line 9, and the pulse from the output 20 enters the amplifier 22, from the outputs of the delay line 17, 18, 19, 21 and the amplifier 22, the pulses arrive at the adder 23, forming an output signal.

Thus, the proposed method and device for transmitting information signals allows you to get a significantly higher peak cross-correlation function with increasing energy of only one pulse from five, but not all five pulses. A higher main peak of the inter-correlation function of the received signal makes it easier to identify it among the interference.

Claims (2)

1. A method of transmitting information signals, including encoding an information unit of five pulses in the form of a sequence of three positive, one negative, one positive impulses, encoding an information zero of five pulses in the form of a sequence of three negative, one positive, one negative impulses, transmitting the received sequences in the data transmission medium, and on the receiving side, the received signal is compared with the reference ones by their mutual correlation and, characterized in that the coding of an information unit of five pulses is performed as a sequence of one positive, N times increased one positive, one positive, one negative and one positive pulses, and the coding of information zero of five pulses is performed as a sequence of one negative, increased by N times one negative, one negative, one positive and one negative impulses, and N represents any positive integer greater than one, is transmitted in the received sequence of data transmission medium, and on the receiving side the received signal is compared with the reference by the correlation between them. 2. A device for transmitting information signals, including the transmitting and receiving sides, delay lines, phase-inverse and phase-saving cascades, summing devices, data transmission medium, characterized in that an amplifier is inputted on the transmitting side, the input of which is connected to the cascade forming the second pulse of the five-pulse signal , output - to a summing device connected via a data transmission medium to the receiving side, and on the receiving side a similar amplifier is introduced, the input of which is connected to the output lag delay corresponding to the second pulse of the five-pulse signal, the output of the amplifier is connected to the adder.

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