3. Approbation of the received results
1. To control fold over distortion appearance phenomenon for sine wave with the frequency of 1 kHz changing discretized sampling frequency. To repeat experiment, changing the sine wave frequency. To convince on Kotelnikov’s theory correctness.
2. Transforming quantization level quantity to convenience on which more bites are used for quantization then quantization interval and consequence less quantization error. To build dependence graph. To make conclusions.
4.Test questions
1. Discretization and quantization.
2. The theorem of Kotelnikov. Frequency of Nyquist.
3. Fourier discrete transform. Fourier fast transform.
4. The phenomenon of false frequency.
5.List of References
Дмитриев В.И. Прикладная теория информации: Учебник для вузов. - М.: Высшая школа, 1989.
Тревис Дж. LabVIEW для всех. М.:LVR Пресс, 2004, - 544с.
Пейч Л.И., Точилин Д.А., Поллак Б.П. LabVIEW для новичков и специалистов. М.: Горячая линия – Телеком, 2004, - 384с.
Laboratory work 5
Information characteristics of sources of messages and communication channels
The Purpose: Studying of information characteristics of sources of messages and communication channels
1.Short theoretical data
Redundancy of a source is estimated by redundancy factor
(1)
Productivity of source - this quantity of the information in the message for one second
(2)
Where
- average duration of one message;
- average speed of creation of the message a source.
Unit of measure of productivity of 1 bits per second.
Speed of information transfer on channel - this quantity of the information on an exit for one second,
(3)
Where
- average speed of transfer of the message on the channel;
- average duration of the message in a communication channel.
The major characteristic of channel - is bandwidth. It is defined as the greatest possible speed of information transfer on a communication channel
[Bin.unit./s] or [bit/s]. (4)
Bandwidth of the discrete channel without hindrances
[Bit per second]. (5)
Bandwidth of a binary symmetric communication channel c a channel matrix
Where p0 - the probability of an error, is defined by expression
(6)
According
to the theorem of Shannon of coding for the discrete channel with
noises: if the source has entropy H (X), and communication channel -
bandwidth C the source message always can be coded so that speed of
their transfer
will
be close to value
, (7)
and the probability of an error will be less the than set size.
For the continuous channel with hindrances bandwidth is defined by expression:
(8)
Where
;
- entropy of a noise; fk
- boundary frequency пропускания
the channel; Pxk
- the average capacity of a signal supposed in the channel;
- average capacity of a hindrance in the channel;
- the relation a signal - hindrance.
The maximum quantity of the information which it is possible to transfer on a communication channel during Tk,
(9)