User Guide (Version 2.2) of the
SiRad Simple® Evaluation Kit
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4.2.4 How does the Auto Gain Control (AGC)-Mode work?
The AGC algorithm uses the first two ramps of each measurement to elaborate the highest gain
setting without saturating the ADC or the baseband amplifier. In each of the two ramps the
controller samples two gain stages while switching on an attenuation network during the first ramp.
After that, the controller has 4 gain settings to choose from for the subsequent measurement.
4.2.5 Can I trigger the SiRad Simple® manually?
Yes. Please read Section 3.2.3.1 about the triggering options.
4.2.6 Can I use multiple SiRad Simple® sensors in parallel?
Yes. You can synchronize the sensors using the pre-trigger feature. We suggest either driving them
in different frequency ranges so they do not interfere, or you trigger them manually to measure
alternately. Please read Section 3.2.3.1 about the triggering options.
4.2.7 The LED goes off when I connect to the WebGUI.
This is because the WebGUI sends a different configuration to the sensor when it is connected.
The LED will light again when the proper serial port (SER1 for the SiRad Simple®) is set in the
‘System Configuration’ tab and the LED mode is changed from off to 1
st
target rainbow.
4.2.8 The RF Parameters tab does not show the min / max frequencies properly.
You can try a manual min / max frequency scan by clicking the ‘fscan’ button three times.
4.2.9 How do I choose a base-frequency?
The base frequency should be at least 100 MHz above the minimum frequency and far away from
the maximum frequency. For small bandwidths, you may choose the base frequency 500 MHz or
more above the minimum frequency for an improved signal quality.
Please be aware, that in most
countries the base frequency has to bet set between 122 GHz and 123 GHz for production
purposes by law. Please check your local regulations.
4.2.10
How do I set the maximum bandwidth in the RF Parameters tab?
Click the ‘max BW’ button three times to set the maximum possible bandwidth for the frontend.
4.2.11
How do I choose a bandwidth?
The smaller the bandwidth, the greater will the range of the sensor become. However, with larger
bandwidths the accuracy will decrease.
Please be aware, that in most countries the bandwidth
is limited to 1 GHz between 122 GHz and 123 GHz for production purposes by law. Please
check your local regulations.
4.2.12
How can I choose the ramp time?
The ramp time can only be set indirectly by adjusting the ADC clock divider and the number of
samples, please read Section 3.2.5.
4.2.13
What is the MTI-Mode?
The Moving Target Indicator mode. When activated, the sensor displays the difference between the
current measurement and the average of the previous measurements (set by ‘Average n’ slider).