- •Contents
- •Introduction
- •General direction to carrying out of laboratory work and technical safety rules
- •A rules of laboratory work decoration
- •Laboratory work 1 Study of the determined signals characteristics
- •1.The Procedure.
- •3. Approbation of the received results
- •Test questions
- •List of references
- •Laboratory work 2 Spectral representation of periodic and acyclic signals
- •Short theoretical data
- •2.The procedure.
- •3.Test Questions
- •List of References
- •Laboratory work 3 Characteristics of random processes (signals, noises)
- •Short theoretical data.
- •The Procedure.
- •Approbation of the received results
- •4.Test Questions
- •Laboratory work 4 Methods of quantization and discretization of signals
- •1. Short theoretical data
- •1.1. Discretization
- •1.2. Fourier Fast transform.
- •1.3. Quantization
- •2.Study of processes of discretization and quantization
- •2.1. Discretization.
- •2.2. Quantization
- •3. Approbation of the received results
- •4.Test questions
- •5.List of References
- •Laboratory work 5
- •Information characteristics of sources of messages and communication channels
- •1.Short theoretical data
- •2.Solution of standard examples
- •3. Tasks for independent work
- •4.Approbation of the received results
- •5.Test questions
- •Laboratory work 6 Effective coding of messages. Codes of Shannon – Fano, Haffman.
- •1.Short theoretical data.
- •2. The procedure.
- •3. Approbation of the received results
- •4. Test questions
- •Laboratory work 7 Noiseproof coding. HAmming Code
- •2. The procedure.
- •2. Approbation of the received results
- •3.Test questions
- •Laboratory work 8 Cyclic codes
- •1.Short theoretical data
- •Coding with the using of cyclic codes
- •2.The Procedure.
- •2.1. Research of data transform with binary symmetric channel and bch code with fixing length of coding combination..
- •2.2. Research of a data transmission system with the bch codes when using the Gaussian channel
- •3.Approbation of the received results
- •4.Test questions
- •Laboratory practical work for the discipline “the applied theory of information”
2.The procedure.
1. Research of the spectrum differentiating ability.
a) to choose frequency of the basic tone f1, amplitudes of both signals of the two - tone generator - equal each other. Number of readout N 1000.
Changing frequency of the second tone f2, to define the minimum difference of frequencies ∆f = |f1−f2 | at which both tones differ in a signal spectrum (to consider that they differ if between them there is at least one harmonic smaller on size). To spend these measurements at increasing number of readout N and to construct dependence of the spectrum analyzer differentiating ability of a ∆f from N. To construct some characteristic spectrograms.
b) to spend specified in point (a) measurements for a mix of a signal with small noise. To construct the given dependences for different number of averaging’s: M=1, 10, 100.
2. Research of a spreading spectrum phenomenon.
a) to give on an input of the analyzer of a spectrum an one - voice - frequency harmonious signal (amplitude of the second tone to establish equal to zero). To choose amplitude and frequency of a signal. Changing number of readout N to watch change of the form of spectra. To construct some characteristic spectrograms.
To define a set of values N at which the spectrum is ideal (doesn't contain additional harmonics). To construct dependences of the relation of size of the basic harmonic to next (in decibels) from N. To construct the schedule of dependence of width of a spectrum at level −20 dB from N.
b)To give on an input of the analyzer of a spectrum a two - tone signal. To choose amplitude of the second tone small in comparison with amplitude of the core. To find the minimum difference of frequencies for which the harmonic of the second tone can be distinguished against the first. To spend these measurements for different forms of a time window and to define, what window is better for you - Divisions of weak signals. To construct characteristic spectrograms.
3. Research of influence of averaging on quality of a spectrum of capacity of random signals.
a) to give on an input of the analyzer a noise signal. To construct a number of spectrograms, consistently increasing number of averaging’s at calculation of a spectrum of capacity. To construct dependence of statistical stability on number of averaging’s and to compare to the theoretical. To spend measurements for several values of number of readout N. How statistical stability depends from N?
b) to choose any frequency. To construct for this frequency of 20 −30 values of size of a harmonic on the chosen frequency in the absence of averaging. To estimate average value and a root - mean - square deviation. To spend the same measurements at M=10 and to compare results.
c) the tax on an input of the spectrum analyzer of a mix of an one - voice - frequency harmonious signal with noise. To define the relation a signal/noise, as the relation of size of the basic peak corresponding to a regular signal to average size of a noise pedestal (in dB). To construct dependence of this relation on number of averaging’s M.