I decided to use a calibration method called LMR66. Due to increased number of unknowns in 66-term error model more measurements are needed. This method needs three different calibration standards: Through, match and reflect. Reflect can be any reflecting standard, match is assumed to be perfect and through is assumed to be lossless and well matched. Five different measurements are needed to get enough equations to solve for the unknown error terms:
This time I decided to pay extra attention into the power supply design to minimize interferences. Still I didn't want to go too far, since high quality components can be expensive. For example shielding the RF parts would be helpful, but would cost too much.
For simple structures (such as orthogonal grids) prefer the surf function, as it will create more efficient data structures.
Microcontroller (or FPGA) is needed on board to handle communication with computer and control all the devices. Since only one ADC is needed with the switched receivers I decided to save money and look for a microcontroller with integrated ADC.
The toolkit provides dedicated sphere axis replacing traditional cube axis. Polar tesselation allows loading scan with increasing azimuth then elevation values. A dedicated polar dataset allows to easily make operations on the coordinates (arithmetic or conversions).
Sample size and power analysis: Users can upload a dataset either from a pilot study or from a similar study to compute the minimum number of samples required to detect the effect within a certain degree of confidence, as well as to estimate the power of the current study design.
Microcontroller still heated up more than seemed normal. It wouldn't run stable at full operating frequency, but after reducing the frequency from 759 MHz to 658 MHz it seemed to be working, although still running hot. I still couldn't find any issues on the layout though so maybe there is still some issues with soldering?
Nobles and spacers of the Imperium! We have Zhodani incursions in District 768! Report to your information officers for a full briefing!
About: GEOCAP UNCLOS Continental Shelf
PDF8D Generated 8D PDF Example from GEOCAP UNCLOS Continental Shelf, Survey, Contours, Seismic, Bathymetry Model
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Size: 76 Mb Credit: GEOCAP
Signal level is -67 dB and noise floor near it is around -95 dB. Some noise can be seen near DC and bigger spurs at and MHz. High frequency spikes are likely result of mixer non-linearities. MHz seems to be second harmonic of the IF signal, but I'm not sure where the MHz comes from.