# The method of discrete information transmission

The invention relates to the field of radiocommunications, telecommunications and computing, and more particularly to methods and devices for data transmission in computer networks. The invention consists in the conversion of the input message signal at the transmitting end of a communication line into a sequence of code combinations consisting of n information bits, are added to each code combination of information bits k - control bit, the combination of which is determined depending on the combination of n information bits, and on the receiving end of the communication line restoring messages from received code combinations and applying it to the target device, and the transmitting end of a communication line combination of k control bits are selected in accordance with the symbol_{i}determined by summing modulo P=2^{k}_{i}corresponding to the combination of k - selected information bit symbol_{i-1}appropriate combinations of k - control bit of the previous code messages_{i}=_{i-1}+^{*}_{i}for the selected combination of k information bits by adding modulo P=2^{k}_{i}corresponding to the received combination of the control bits, with the dual symbol^{c}_{i-1}corresponding to the combination of the control bits of the previous code messages^{*}_{i}=_{i}+^{c}_{i-1}(mod P), where^{c}_{i-1}=P-_{i-1}compare the generated corrective characters^{*}_{i}with characters_{i}appropriate combinations of k - selected and received data bits, in this case, if there is no distortion in two adjacent matching symbols replace all distorted combination of k - selected information bits_{i}in combination, appropriate corrective characters_{i}for the combination of k - selected data bits, and if there are differences in the two adjacent comparison ^{*}_{ii+1}then correct the distorted adjacent combinations of k - selected and received information bits only for the case when the combination of the control bits is not distorted. Technical result achieved in the implementation of the invention is to increase the noise immunity of discrete information transmission 2 C.p. f-crystals, 1 Il.

The invention relates to the field of radiocommunications, telecommunications and computing, and more particularly to methods and devices for data transmission in computer networks.

Known methods of discrete information transmission (see, for example, [1] pages 357-369, [2] pages 200-231, the application for invention No. 99120097/09 from 17.12.1998 [3]).

In the known methods the transmission of discrete information is carried out by converting the message into a sequence of perceptible signals (code combinations, which change so that they have the ability to detect and correct errors in reception caused by interference, and to recover messages from received code combinations.

Known methods provide a robust connection, but have a large excess is appropriated method is a method, described in [1] page 358. The method includes transmitting end of a communication line conversion of the input message signal into a sequence of code combinations consisting of n information bits, is added to each code combination of information bits k - control bit, the combination of which is determined depending on the combination of n information bits, and on the receiving end of the communication line is carried out restoration messages from received code combinations and feeds it to the target device.

However, the prototype method has a drawback. With increasing noise in the communication line and active intrusion reduced immunity because correcting capability of the code is limited to input redundancy.

Thus, the invention solves the problem of increasing noise immunity due to noise conditions.

This is achieved by the known method of transmitting digital data, which consists in the conversion of the input message signal at the transmitting end of a communication line into a sequence of code combinations consisting of n information bits, are added to each code combination of information bits k - control bit, the combination of which is determined in zavisimost for the adopted code combinations and applying it to the target device according to the invention on the sending end of the line, a combination of k - the control bits are selected in accordance with the symbol_{i}determined by summing modulo P=2^{k}symbol a_{i}corresponding to the combination of k - selected information bit symbol_{i-1}appropriate combinations of k - control bit of the previous code messages_{i}_{}_{i-1}+a_{i}(mod P), and on the receiving end of the communication line for each code combination form a corrective character and^{*}_{i}for the selected combination of k information bits by adding modulo P=2^{k}_{i}corresponding to the received combination of the control bits, with the dual symbol^{with}_{i-1}corresponding to the combination of the control bits of the previous code combination of the message and^{*}_{i}_{}_{i}+^{c}_{i-1}(mod P), where^{c}_{i-1}=P-_{i-1}compare SFOR is selected and received information bits, if there is no distortion in two adjacent matching symbols replace all distorted combination of k - selected data bits and_{i}in combination, appropriate corrective symbols a^{*}_{i}for the combination of k - selected data bits, and if there are distortions in two adjacent matching symbols and_{i}and^{*}_{i}and and_{i+1}and^{*}_{i+1}then form a corrective characters^{*}_{i}for combinations of control bits by adding modulo P=2^{k}symbol and_{i}corresponding to the combination of k - selected and received information bits with all the previous characters corresponding to the combinations of k - selected and received data bits of this message^{*}_{i}_{}a_{i}+^{*}_{i-1}(mod P), compare them with the symbols_{i}appropriate combinations of k - adopted control bit and correct distorted adjacent combinations of k - selected and received information bits if there are any discrepancies in the following two combinations of control

discrete information are messages or data written in binary code and represented by the signal as a sequence of zeros and a single bit;

the symbol is a number, for example, and recorded in the form of digits of the binary number system and is represented as a sequence (combination) of zero and a single bit, if we assume that the position of each bit_{i}corresponds to the binary digit a=2^{0}^{}_{0}+2^{1}^{}_{1}+2^{2}^{}_{2}+... +2^{n-1}^{}_{n-1};

- the ratio of comparability (a=b(mod p)) and comparable to b modulo p: two numbers a and b are called comparable modulo p, if you divide both numbers by R residues are equal;

- addition of numbers a and b modulo p means that two numbers are added in the usual way, and their sum is translated into a nite set by comparing modulo R.

These distinctive features in comparison with the prototype allows to make a conclusion on the conformity of the proposed technical solution the criterion of "novelty".

In the proposed method provides higher noise immunity due in relation to the prototype, because the combination of the control bit added to the code combination of the message is determined not only by the combination of the information bits of a given code combination, and combinations of information bits of all the previous code combinations of messages. For the used encoding combinations of control bits for the distortion of a single coded combinations of control bits error when decoding this combination extends to neighboring decoded combination, and when distorted one combination of data bits in the encoding process control bit error applies to all subsequent coded combination. These properties are used by the code allows not only to detect distorted when receiving a combination of k - selected data bits and to correct any distorted bits of these code combinations on the receiving end of the communication line. Due to this increased the number of corrected bits in all of the transmitted message, which increases the robustness of the connection.

It is a new property set of features, leading to increased noise due to interference conditions and active intrusion, allows to conclude with the transmission of discrete information tested in laboratory conditions. An example implementation of this method using the device shown in the drawing, where:

unit 1 - the signal source;

unit 2 - the encoder;

block 3 - transmitter;

unit 4 - the receiver.

unit 5 - decoding device;

unit 6 - the target device.

Signal as a sequence of zeros and a single bit {1110000010000110001010011110100011100100101101110110} in unit 2 is converted into a sequence of code combinations{1110, 0000, 1000, 0110, 0010, 1001, 1110, 1000, 1110, 0100, 1011, 0111, 0110}, which corresponds to the sequence of characters{14, 0, 8, 6, 2, 9, 14, 8, 14, 4, 11, 7, 6}.

For ease of description of the operation of the device will assume that for each combination of the 4 data bits (n=4) add 3 control bits (k=3). In this case, P=2^{k}=8. In each code combination choose 3 information bits, the combination of which will be subject to adjustment in the event of incorrect reception of bits. Selected sequences of combinations of information bits{110, 000, 000, 110, 010, 001, 110, 000, 110, 100, 011, 111, 110} match a sequence of characters and={6, 0, 0, 6, 2, 1, 6, 0, 6, 4, 3, 7, 6} and is determined by the formula_{i}_{}_{i-1}+a_{i}(mod P), the sequence solidautoeject combinations of control bits {110, 110, 110, 100, 110, 111, 101, 101, 011, 111, 010, 001, 111}. The control bits are added to information bits and the message in coded form{1110110, 0000110, 1000110, 0110100, 0010110, 1001111, 1110101, 1000101, 1110011, 0100111, 1011010, 0111001, 0110111} transfer devices 3 and 4 on the receiving end of the communication line. In a decoding device 5 adopted a distorted combination of correct data bits and the recovered message serves on the target device 6.

For example, if you receive a message each second code combination has distorted all the selected data bits, then the sequence of symbols received combinations would be a={1, 0, 7, 6, 5, 1, 1, 0, 1, 4, 4, 7, 1}, and calculated according to the formula and^{*}_{i}_{}_{i}+^{c}_{i-1}(mod P), where^{c}_{i-1}=P-_{i-1}the sequence of corrective characters and^{*}={6, 0, 0, 6, 2, 1, 6, 0, 6, 4, 3, 7, 6} will be different from that adopted in each of the second code combination. If the message control bits are not distorted, because otherwise there was divergence of the compared characters a and a^{*}in two adjacent code combinations.following up on corrective symbols {6, 0, 2, 6, 6, 3, 6}, which corresponds to the bit combination{110, 000, 010, 110, 110, 011, 110}.

If distorted all the selected data bits in two adjacent combinations, for example in the third and fourth, and instead of code combinations {000, 110}, which correspond to the symbols {0, 6}, accepted combinations of {111, 001, which correspond to the symbols {7, 1}, then the sequence adopted is not distorted combinations of control bits, which corresponds to a sequence of characters={6, 6, 6, 4, 6, 7, 5, 5, 3, 7, 2, 1, 7}, will differ from that calculated by the formula^{*}_{i}_{}and_{i}+^{*}_{i-1}{mod P) sequence of corrective control characters{6, 6, 5, 6, 0, 1, 7, 7, 5, 1, 4, 3, 1} in all subsequent compare the characters. In this case, the only correct distorted information bits in two adjacent code combinations.

If the message is distorted all control bits, for example in the third combination, and instead of the code combinations of {110} will be adopted by the combination of {001}, and the information bits of the message is not distorted, then the sequence of characters for the combination of the received control bit^{*}_{i}_{}a_{i}+^{*}_{i-1}(mod P) sequence of corrective control characters^{*}={6, 6, 4, 4, 6, 7, 5, 5, 3, 7, 2, 1, 7} only one-third code combination and the sequence of characters for combinations of the received data bits and={6, 0, 0, 6, 2, 1, 6, 0, 6, 4, 3, 7, 6} will differ from the calculated sequence of corrective information symbols a=^{*}{6, 0, 0, 3, 3, 1, 6, 0, 6, 4, 3, 7, 6} in the third and fourth code combinations. In this case, adjusted only all distorted control bits in the third code combinations.

For the considered example of the method of discrete information transmission when transmitting messages containing 30 code combinations using 4 white and 3 control bits can be corrected to 60 information bits that can be distorted in 20 code combinations. At the same time prototype method, in which control bits are chosen optimally to adjust one code combination, allows under the same conditions to correct one bit in the code combination, and considered the message to be adjusted up to 30 inform the years of the prototype method to the number of control bits in one code combination to increase to six. Only in this case, the message can be corrected 60 information bits.

If instead of the 3 control bits in the above example will be used 4 bits, the proposed method allows to correct up to 80 data bits in the message, while the efficiency of the prototype method will not change and will be 30 corrected bits in the message, since the optimal number of control bits k to adjust the r bit in the code combination is determined by the expression

Thus, the proposed method compared to the prototype provides better interference resistance of the connection.

If each code combination of data bits which must be corrected will choose depending on their importance, that reduces the damage caused by interference and active intrusion in the process of information transfer.

When determining combinations of control bits, and when computing information and control characters in the proposed method, instead of adding characters modulo P can be used in the operation bits bitwise addition modulo two.

Implementation of the proposed method is straightforward, since all the re.

Sources of information

1. Bychkov, S. I. Space radio systems. - M.: Soviet radio, 1967.

2. D. D. Klovsky Theory of signal transmission. - M.: Communication, 1973.

3. Device for encoding/decoding N-bit source words into corresponding M-bit channel words, and Vice versa. Application for invention No. 99120097/09 from 07.12.1998 - IPC 7 H 03 M 7/00.

Claims

1. The method of discrete information transmission in systems with feedback, including on the sending end of the line dividing the input signal into blocks of length n-bits, the sequence of blocks of length n-bits remember, form the message and transmit the generated message on the communication line, and on the receiving end of the line, remember the message, pass it through the feedback channel on the transmitting end of the line, take the message on the sending end of the line and compare the transmitted and received messages, pass on the receiving end of the communication line follow-up messages, if the comparison of the transmitted and received messages are the same, pass on the receiving end of the communication line commands for erasing messages if you compare the messages do not match, and re-transmit the generated message is mnom end of the line received message code each symbol in the message is determined in accordance with the formula

_{i}=_{i-1}+_{i}(mod P),

where P=2^{n};

the characters,are numbers written as digits in the binary number system and is represented as a sequence (combination) of zero and a single bit;

_{i},_{i}the symbol and the encoded symbol generated messages;

_{i-1}- previous encoded symbol generated message

and on the sending end of the line, the transmitted message code similarly as on the receiving end of the communication line, compare transmitted and received coded messages and transmit to the receiving end of the line commands for erasing messages if you compare the transmitted and the received encoded messages are differences in two or more adjacent characters.

2. The method according to p. 1, characterized in that the coding of messages at the receiving and transmitting ends of the link is performed by a bitwise slorenia.

3. The method according to p. 1 or 2, characterized in that the symbols of the transmitted message code on the transmitting end of the communication line correcting code that corrects single errors, and on the receiving end of the communication line perform decoding of the received symbols and their adjustment.

**Same patents:**

FIELD: Witterby algorithm applications.

SUBSTANCE: system has first memory element for storing metrics of basic states, multiplexer, capable of selection between first and second operating routes on basis of even and odd time step, adding/comparing/selecting mechanism, which calculates metrics of end states for each state metric. Second memory element, connected to adding/comparing/selecting mechanism and multiplexer is used for temporary storage of end states metrics. Multiplexer selects first operating route during even time steps and provides basic states metrics, extracted from first memory element, to said mechanism to form end state metrics. During odd cycles multiplexer picks second operating route for access to second memory element and use of previously calculated end state metrics as metrics of intermediate source states.

EFFECT: higher efficiency.

2 cl, 9 dwg

**FIELD: communications engineering.**

**SUBSTANCE: proposed device and method for mobile code-division multiple access communication system including device for transferring channel of backward-link transmission speed indicator afford generation of optimal code words ensuring optimal coding for all types of coding procedures from optimal type (24.1) up to optimal coding procedure 24.7 and supporting all optimal-coding devices.**

**EFFECT: optimized capacity.**

**74 cl, 21 dwg, 44 tbl**

FIELD: communications engineering; network remote measuring and control systems.

SUBSTANCE: proposed noise-immune cyclic code codec designed for data transfer without pre-phasing has on sending end code-word information section shaper incorporating shift-register memory elements, units for computing verifying parts of noise-immune code of code-word information section, and modulo two adder of code-word information section shaper; code-word synchronizing section shaper and modulo two adder of code-word synchronizing section; on receiving end it has binary filter incorporating binary-filter shift register memory elements, computing units for verifying parts of binary-filter noise-immune code, and binary-filter modulo two adder; shift register of code word information section; decoder; accumulator; error correction unit; unit for shaping synchronizing section of code word; and modulo two adder units.

EFFECT: enhanced speed of device.

1 cl, 1 dwg

FIELD: communications engineering; network remote measuring and control systems.

SUBSTANCE: proposed noise-immune cyclic code codec designed for data transfer without pre-phasing has on sending end code-word information section shaper incorporating shift-register memory elements, units for computing verifying parts of noise-immune code of code-word information section, and modulo two adder of code-word information section shaper; code-word synchronizing section shaper and modulo two adder of code-word synchronizing section; on receiving end it has binary filter incorporating binary-filter shift register memory elements, computing units for verifying parts of binary-filter noise-immune code, and binary-filter modulo two adder; shift register of code word information section; decoder; accumulator; error correction unit; unit for shaping synchronizing section of code word; and modulo two adder units.

EFFECT: enhanced speed of device.

1 cl, 1 dwg

FIELD: communication systems.

SUBSTANCE: method includes generating sets of sub-codes of quasi-additional turbo-codes with given encoding speeds, and given sub-codes are reorganized as a set of sub-codes with another encoding speed for use in next transfer of sub-code with given encoding speed.

EFFECT: higher efficiency.

9 cl, 13 dwg

FIELD: data transfer technologies.

SUBSTANCE: method includes segmentation of length N of quasi-complementary turbo-codes on preset amount of sections, determining identifiers of sub-code packets appropriate for segmented portions, setting of said packets separated for initial transfer of sub-code, calculation of number of remaining symbols in form N-Fs, where N - length of quasi-complementary turbo-codes, and Fs - position of start symbol of sub-code of quasi-complementary turbo-codes, determining position of symbol of remaining symbols in amount equal to sub-codes amount, which have to be sent and serial transfer of sub-code symbols from position of starting symbol Fs to position of last symbol Ls.

EFFECT: higher efficiency.

5 cl, 17 dwg

FIELD: communications engineering.

SUBSTANCE: method includes selecting one combination among given combinations, appropriate for several or every generated symbols of code word to transmit generated symbols of code word with length of sub-packet, determined in accordance to data transfer speed, information, appropriate for data transfer speed, is read, also based on length of sub-packet and chosen combination, from a table, wherein identification information, pointing at data transfer speed, sub-packet length and selected combination, is, is previously displayed for given information, and generated code word symbols are transmitted in accordance to read information and in accordance to selected combination.

EFFECT: possible check transmission of information by means of hybrid automatic repeat query for increasing carrying capacity during high-speed information transfer.

4 cl, 16 dwg, 6 tbl

FIELD: communications engineering; simulating digital communication channels with separate and grouping errors.

SUBSTANCE: proposed method includes evaluation of set of communication channel states S_{0},S_{1}, ..., S_{m - 1} and calculation of conditional error probabilities P(e/s) in each state s" i = 0, ..., m - 1 of communication channel, and error acquisition in communication channel in compliance with conditional error probability for current state of communication channel; in the process probability of error-free interval p(0^{i}) of i bits is found, and conditional probabilities p(0^{i}1/11), p(0^{i}1/01) of error-free intervals of i bits are calculated with respect to them basing on probabilities p(0^{i}) and using recurrent rules during each current time interval and preceding one on condition that for error generation use is made of two states of communication channel corresponding to combination of errors 11 or 01; random number p uniformly distributed within interval between 0 and 1 is generated; conditional probabilities p(0^{i}1/11), p(0^{i}1/01) are summed up starting from i = 0 resulting in sequence 0^{k}1 that constitutes bit-by-bit stream of communication channel errors.

EFFECT: enhanced speed.

1 cl, 1 tbl

FIELD: communications engineering; data transfer, telemetering, and telecontrol systems.

SUBSTANCE: proposed codec has on sending end code-word data part shaper whose output and that of code-word synchronizing part shaper are connected to modulo two adder input; on receiving end it has binary filter whose code-word data part shaper output is connected to accumulator connected to synchronizing sequence decoder and to error connection unit whose outputs are connected to respective inverting inputs of code-word data part shaper; output of the latter functions as data output of device; output of binary-filter code-word synchronizing part is connected through switching unit to input of code-word data part shaping unit; synchronizing sequence decoder output is connected to control input of switching unit and to error correction unit input; on receiving end accumulator outputs are connected to inputs of code-word data part shift decoder whose output is connected to input of delay circuit whose output functions as second control input of switching unit and as synchronizing output of device.

EFFECT: enhanced noise immunity.

1 cl, 1 dwg

FIELD: coding in communication systems.

SUBSTANCE: proposed partial reverse bit-order interleaver (P-RBO) functions to sequentially column-by-column configure input data stream of size N in matrix that has 2^{m} lines and (J - 1) columns, as well as R lines in J column, to interleave configured data, and to read out interleaved data from lines.

EFFECT: optimized interleaving parameters complying with interleaver size.

4 cl, 7 dwg, 3 tbl