| 2,13 → 2,6 |
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| The whole design of the radioastronomic receiver digitization unit is meant to be used in a wide range of applications and tasks related to digitization of a signal. A good illustrating problem for its use is the signal digitization from multiple antenna arrays. Design and implementation of the system is presented in this chapter. |
| |
| \midinsert |
| \clabel[expected-block-schematic]{Expected system block schematic} |
| \picw=\pdfpagewidth \setbox0=\hbox{\inspic ./img/Coherent_UHF_SDR_receiver.png } |
| \par\nobreak \vskip\wd0 \vskip-\ht0 |
| \centerline {\kern\ht0 \pdfsave\pdfrotate{90}\rlap{\box0}\pdfrestore} |
| \caption/f Expected realization of signal digitalisation unit. |
| \endinsert |
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| \sec Required parameters |
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| 58,8 → 51,19 |
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| \sec System description |
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| This section deals with the description of the trial version based on Xilinx ML605 development board, see Figure~\ref[ML605-development-board], available at the workplace. This FPGA parameters are more than sufficient of what we need for the fast data acquisition system being developed. |
| This section deals with the description of the trial version based on Xilinx ML605 development board, see Figure~\ref[ML605-development-board], available at the workplace. This FPGA parameters are more than sufficient of what we need for the fast data acquisition system being developed. Expected system configuration is shown in Figure~\ref[expected-block-schematic]. The system consist antennas equipped by |
| |
| %% dopsat celkovy popis systemu. |
| |
| \midinsert |
| \clabel[expected-block-schematic]{Expected system block schematic} |
| \picw=\pdfpagewidth \setbox0=\hbox{\inspic ./img/Coherent_UHF_SDR_receiver.png } |
| \par\nobreak \vskip\wd0 \vskip-\ht0 |
| \centerline {\kern\ht0 \pdfsave\pdfrotate{90}\rlap{\box0}\pdfrestore} |
| \caption/f Expected realization of signal digitalisation unit. |
| \endinsert |
| |
| |
| \secc Frequency synthesis |
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| We have used a centralized topology as a basis for frequency synthesis. One precise high-frequency and low-jitter digital oscillator (GPSDO\glos{GPSDO}{GPS disciplined oscillator}) has been used \cite[MLAB-GPSDO]. The other working frequencies have been derived from it by the division of its signal. This central oscillator has a software defined GPS\glos{GPS}{Global Positioning System} disciplined control loop for frequency stabilization.\fnote{SDGPSDO design has been developed in parallel to this diploma project as a related project, but it is not explicitly required by the thesis itself and thus it is described in a separate document.} |
