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THE STATE COMMITTEE OF COMMUNICATION AND INFORMATION OF UKRAINE

The ODESSA NATIONAL ACADEMY of COMMUNICATION named after А.S. POPOV

Methodical instructions and the task for course work on discipline «data transmission systems»

For students 3 courses

Odessa 2010

1. THE GENERAL REMARKS

Course work on the discipline “Data transmission systems” is devoted designing of modern system of the data transmission using standard procedure of channel level.

2. VARIANT CHOICE

The task for the work is made for 100 variants. Values of set parameters get out depending on two last figures of the record book. Some parameters are the general for all variants.

3. REQUIREMENTS TO TYPOGRAPHY

The course work is desirable for performing on a white paper of format А4, being guided by degree project typography rules.

4. THE LITERATURE LIST

1. Transfer of discrete messages: the Textbook for high schools/century P.Shuvalov, N.V.Zaharchenko, etc.; under the editorship of V.P.Shuvalov. М: Radio and communication, -990.

2. Studying of principles of construction of codecs of a cyclic code

3. Unilateral systems of transfer

4. Studying of principles of construction of shots of channel level of a link of data transmission. (Procedure HDLC, report Х.25 МКТТ); the Method. A management, Odessa; Изд. ОЭИС, 1992.

5. Studying of process of transfer of shots of channel level of a link of data transmission (Procedure HDLC, report Х.25 МКТТ). A method. A management, Odessa, Изд. ОЭИС, 1993.

6. Algorithms of DEWS

7. The book green

5. The task for course work

It is necessary:

To provide the specified fidelity by using DT system with a solving feedback on the basis of procedure HDLC. For detection of errors use a cascade code, and for correction – repetition of incorrectly accepted information in a mode with expectation.

It is required:

1. To calculate key parameters of a cyclic code, this will be used in course work as an internal code of a cascade code. To synthesise a code combination of the CC according to the calculated parameters. To check up correctness of reception code combination in the binary form.

2. To code the received sequence by external code in which quality to use not regular convolution code (7, 5). To calculate the redundancy brought by a cascade code, and also frequency rate of errors which it can find out and correct. To check up correction of double errors by entering of errors into sequence (numbers of erroneous elements correspond to two last figures of the record book)

3. To make an information frame according to following data: the station-addressee address – 2 last figures of the record book in the binary form; number of a transferred information frame – group number; information sequence – the sequence received in item 2; a serial number of an expected information frame – 0.

4. To construct block diagram DT with SF and its time diagram of work in scale. To calculate key parameters of the specified transmission system.

5. To generate service frames on procedure HDLC, which are necessary for information transfer process on a communication channel.

6. To show realisation of systems DT with SF, using procedure HDLC. To use the basic format of transfer of frames in case last figure of the record book is even, and expanded – otherwise. Erroneous to consider bytes with numbers corresponding to two last figures of the record book.