SU1594707A1 - Device for regenerating bi-pulse signals - Google Patents

Abstract

The invention relates to telecommunications. The aim of the invention is to improve the noise immunity of the device. A device that receives and recovers a bi-pulse signal contains an amplifier 1, a generator of 2 pulses, a synchronizer 3, a block 4 of analog memory, a block 5 of comparison, a trigger 6 and a driver 7 of bi-pulse signals. 8 ill., 1 tab.

Description

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The invention relates to telecommunications and can be used in regenerators of digital transmission systems, as well as in the reproduction of digital information recorded on magnetic media by phase manipulation.

The purpose of the invention is to improve the noise immunity of the device.

FIG. 1 shows a block diagram of a device for regenerating bi-pulse signals; in fig. 2 - diagrams of the bi-pulse signal; FIG. 3 is a graphical representation of a plurality of two-bit code words and their division into regions of correct reception; in fig. 4 - voltage plots for the device operation; in fig. 5 - functional synchronizer circuit; in fig. 6 is a functional block diagram of analog memory; in fig. 7 is a functional block comparison circuit; in fig. 8 is a functional diagram of a bi-pulse signal generator.

The device for regenerating bi-pulse signals contains (Fig. 1) amplifier 1, generator of 2 pulses of a fixed clock frequency, synchronizer 3, block 4 of analog memory, block 5 of comparison, trigger 6, driver 7 of bi-pulse signals, output 8 of amplifier, output 9 of pulse generator The first to sixth outputs 10–15 of the synchronizer, the outputs 16 and 17 of the memory block, the output 18 of the comparison block, the direct and inverse outputs 19 and 20 of the trigger 6, and the output 21 of the device.

The synchronizer contains (figure 5) trigger., Ger 22, elements And 23-28, resistors 29-31, capacitors 32-34, triggers 35 and 36, and element 37 of equivalence.

The analog memory block (Fig. 6) is implemented on a decoder 38 and capacitors 39 and 40. The comparison unit (Fig. 7) is implemented on an operational amplifier 41, an equivalence element 42 and a trigger 43. A bi-pulse driver (Fig. 8) is performed on a multiplexer 44 and a pulse transformer 45.

The bi-pulse signal is represented as a two-dimensional binary code over the alphabet of symbols {1, -1}, the allowed code words are two code words: (1, -1) and (-1.1) (FIG. 2), and prohibited (1,1) and (-1, -1). In order for the decoding of such a code to be complete (and the reception of the pulsed signal is optimal), the set of all codewords is divided into two subsets, each of which is an area of correct reception for the corresponding allowed code word. The boundary between the two areas is at the same distance from the allowed. code words (fig.Z). The signal at the input of the device is mapped to a point on a plane with coordinates (Xo, Yo), which falls into one of two areas of correct reception. The device makes a decision about which of the two half-planes the display of the received bi-pulse signal falls into, and according to the decision, forms the corresponding bi-pulse output

0 signal.

The device works as follows.

The received mixture of signal and noise from the output of the communication channel or the playback unit of the magnetic recording is fed to the input of amplifier 1, in which the bi-pulse signal is amplified. C. The output 8 of the amplifier 1 (Fig. 4) is fed to the input of the generator 2, which from the received signal 0 selects a double clock frequency. From the output 9 of the generator 2, the signal (Fig. 4) is fed to the input of the synchronizer 3 (Fig. 5), in which the control pulses from 25 outputs 10 to 15 (Fig. 4) are formed from the doubled clock frequency.

From the output of amplifier 1, signals are fed to the information input of block 4 of the analog memory. The control signals received at the control inputs of block 30 4 from the outputs of synchronizer 3, block 4 are recorded and stored until the end of each clock interval (m 1 / fo) readout values of the input bi-pulse signal. From the output of memory block 4, the reading values of the 35 bi-pulse signal are fed to the inputs of the comparison unit 5, to one input 16 from the first output of the memory block 4 receives the reading value of the bi-pulse signal in the first half-cycle, and to the other input 17 from the second output The memory unit 4 receives the readout value of the bi-pulse signal in the second half-cycle (Fig. 4). By gating, it receives a pulse coming from the output 11 of the synchronizer 3, from block 5 of the comparison, the comparison of the two voltages is performed. If the voltage at the first input is greater than the second, then a single level is formed at the output 18 of unit 5. Otherwise - level zero. FIG. 7 shows the implementation of Comparison Unit 5. From the output of block 5, the generated signal is fed to the information input of the driver 7 bi-pulse signals. Trigger 6 divides the doubled frequency in half. The pulses from the inverse 19 and direct 10 outputs of the trigger 6 are fed to the clock inputs of the driver 7 bi-pulse signals. With the appearance of the first gating pulse, a zero permitting is formed at the sixth output 15 of synchronizer 3

the level that enters the control input of the driver 7 bi-pulse signals,

If there is a unit level at the information input of the driver 7, then a bi-pulse signal corresponding to 1 is formed at its output. Otherwise, O. FIG. 8 shows the implementation of the driver 7 of bi-pulse signals.

The probability of correct reception of a bi-pulse signal for the proposed device is equal to

P (e) 1-0, + erf (2Sf00

- / 4-exp (- X) erf (x + 4S) -erf (25) dx.

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dz - integrals calculating P (e) on a computer showed that the probability of an error when receiving a bi-pulse signal with an accuracy of the eighth digit coincides with the expression for the probability of an error Popt (e) when optimally receiving opposite signals:

Popt (e) 0.5 1-erf (B).

The table shows the results of P (e) and Popt (e) as a function of signal-to-noise ratio. A slight discrepancy between P (e) and Popt {e) is explained

the inaccuracy of computer numerical logs caused by the necessity to replace the infinite upper limit in a definite integral with a finite one. Thus, the invention allows

improve the noise immunity of biopulse signal regeneration to the maximum achievable.

FORUMUA AND 3 ABOUT AND

A device for regenerating bi-pulse signals, comprising a pulse generator, whose input is an input of a device, the output of a pulse generator is connected to the synchronizer input, which is so that, in order to improve the noise immunity of the device, a memory block, a comparison block, a trigger and a bi-pulse driver,

the first to sixth inputs of the synchronizer are connected respectively to the trigger input, controlling the input of the comparator unit, the first to the third control inputs of the memory unit and the controlling input of the bi-pulse generator, the information input of the memory unit is connected to the input of the device, the outputs of the memory unit are connected to by the same information inputs of the comparison block,

the output of which, the inverse and direct outputs of the trigger are connected respectively to the informational, first and second clock inputs of the bi-pulse generator, the output of which is

device output

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Claims (2)

A device for regenerating bi-pulse signals, comprising a pulse generator, the input of which is the device input, the output of the pulse generator is connected to the synchronizer input, which means that, in order to increase the noise immunity of the device, a memory block, a block comparisons, trigger and bi-pulse driver, the first - sixth inputs of the synchronizer are connected respectively to the trigger input, the control input of the comparator, the first - third control inputs of the memory block and the control input of the bi-pulse signal generator, the information input of the memory block is connected to the device input, the memory block outputs are connected to the informational inputs of the comparison unit whose output, inverse and direct trigger outputs are connected to the information input of the first and second clock signals of the bi-pulse signal generator, output which is the output of the device. · 2 3 3 . five 6 .7 eight 9 ten eleven Ρορϊ ίθ) 5.62820 Ε-Ό2 3.75062 E-02 2.28785 E-02 1.25009 E-02 5.95385 E-03 2.38827 E-03 7.72655 E-04 1.90884 E-04 3.36170 E-05 3.84450 E-06 2.38419 E-07 R (e) 5.62822 E-02 3.75063 E-02 2.28786 E-02 1.25009 E-02 5.95411 E-03 2.38881 E-03 7.72242 E-04 1.88104 E-04 3.08293 E-05 3.75990 E-06 1.84488 E-07 1594707 1594707 ? π Π Π Π Π Π Π Π Π Π yupppppppppp η π π π π π No. π. ττ— ~ π - cr / to / —ν ΧΣΣ7ΛΖΣΓ α ί— one one I one I one Figm nineteen 21 1594707 Niggle