![]() | Only 14 pages are availabe for public view |
Abstract (i) SUMA1ARY Different ua t hersa t.i ca L models for deoigning digital filters have been discussed and revealed that an optimum frequency r e sp onac cha rac t er Ls t.Lc s (i.e., minimum band width with minimum t erminaloscilla ti ons) are obtained wit hl,n the following constraintG :- 1) The filter ui.z e parameter N. could be taken as high as possible to reduce the vzi.d t h of the response function. Although lower values of N cav e the computation time, an undesired inc- rease in the width of t he response function as well as an inc- rease in the ~pl!tude of the terminal oscillations occured which increase the resp onae for frequencies out of the selected band. 2) The best choise of the filter’s cutoff frequency, Pc’ is zero. (11his permi t s a reduction in the wid t h of the response function whi ch r-ea.Li z.e s a sharp cutoff in the frequency respo- nse characterictics. S) The sine-teruination parameter H should be equal or slightly less than I/N. The present analysis revealed that the deviation between the given value of H and the experimen- tal band width h La vanishes for N > 60. On the other hand, a computational system has been designed for the ECLIPSE 3/23U computer to perform the following : 1) The computations of the filter’s response function without the sine-termination effect. 2) Determination of the parameters ef the suggested sine- termination function. 3) Computations of the final reap onae function for both low- and band-pass filters taking into account the consideration of the suggested aine-function. Before applying the developed system on real data, an investigation for the designed computational system took place |