TTMER5: Equalization of digital line section
Control questions
You must give an answer to 5 questions at the beginning of the laboratory exercise. One
wrong answer will make the mark given to the measuring with one grade worse. Two or more
wrong answers will result a supplementary measuring!
- What kind of transmission characteristic has the network, which has a weight
function containing a late or hurrying echo?
- Draw the block diagram of the T-filter, review its principle!
- Review the build-up of the baseband connection model, and the role of its elements
- What speed of data transmission connection can be equalized with a T unit delayed
T-filter, and in which band can it be applied, as a broadband equalizer?
- Draw the weight function of an N=4-es ideal T-filter, which can provide a near
constant amplitude characteristic!
- What is the amplitude- and phase characteristic of the T-filter, if cn << c0 ?
- Make the approximation of an ideal low-pass filter with a linear phase
characteristic with help of a T-filter having 600-Hz of cut-off frequency and
specifications of 1/2T=1200Hz, N=4. The coefficients to be set must be determined
with a Fourier-serial method. The biggest coefficient value must be 1.
This task can be made at home in advance, and given in with the name of the
student written on it.
- Make the correspondence between the elements of the data transmission connection
and the tools of the measuring place.
- What is the criterion of the distortionless transmssion?
- Draw the amplitude and group delay characteristics of a telecommunication channel!
Draw a characteristic of a line equalizing amplitude and group delay to it, that
if the channel and the equalizer are connected into a cascade, then the resultant
transmission characteristic could fulfill the criterion of the distortionless
transmission in the operation domain of the telecommunication channel.
- On what principle can happen the measurement of the group delay in the EP2 measuring tool?
- Why should we switch the DT10 interface tester to a synchronous operation mode
(FRAMING SYNC) for the record of the eye pattern during the measurement?
- Can we forward the clock signal on the data transmission connection model?
- Wny should we switch the DT10 interface tester to an asynchronous operation mode
(FRAMING ASYNC) for the measurement of the bit error rate?
- What is the eye pattern? How can we display an eye pattern? What conclusions can
we draw from the eye pattern relating to the quality of the transmission?