85,7 → 85,7 |
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% doplnit schema skutecne pouziteho systemu |
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Despite of the schematic diagram proposed at beginning of system description.... |
Despite of the schematic diagram proposed at beginning of system description \ref[expected-block-schematic]. |
We have used two separate oscillators -- one oscillator drives encoded signal to ADCs still through FPGA based divider and the other one drives it to SDRX01B mixer. |
The reason for this modification was an attempt to simplify the frequency tuning during the experiment. A single oscillator may be used only with a proper setting of FPGA divider and this divider may be modified only by recompilation of FPGA code and loading/flashing a new FPGA schema. Due to fact that the FPGA is connected to PCI express and kernel drivers with hardware must be reinitialized, reboot of PC is required every time a FPGA scheme is changed. Instead of this complicated procedure, we set the FPGA divider to a constant division factor of 30 and used another district oscillator for ADCdual01 sampling modules and for SDRX01B receiver. |
We have used ACOUNT02A MLAB instrument for frequency checking of correct setup on both local oscillators. |