Tuning

Tuning Options

In below, there are some tuning options listed, you can adjust the settings of the SiRad evolution kit according to your measurement interest.

How to increase SNR

• Increase number of ramps
• Setting a higher gain

How to increase update rate

There are several steps that you can follow to increase the update rate. Please see the protocol description[1] for detailed information.

• AGC mode disable:

When AGC mode is selected, the kit drives 2 additional ramps in order to determine the suitable gain settings according to the environment.

• Reduce the data transmission time:

Disabling the data frames that you do not need will result in lower transmission time.
Secondly, you might also decrease the transmitted data length (FFT size or number of samples).
Select only one of SER. Therefore the evaluation kit will transfer the data through only one SER.
Activate Binary protocol, due to less size of transmitted data the update rate will increase

• Reduce the number of ramps

Reducing the number of ramps decreases the time or ramping. Reducing the number of ramp affects SNR, you might need to adjust according to your application.

• Reduce the ADC Clk Divider

Smaller ADC Clk divider settings results higher sampling frequencies and therefore shorter sampling time.

• Assign 0 to Self Trigger delay
• Disable unnecessary processing

In order to shorten processing time, unnecessary processing steps can be disabled. Switching off processing steps will depend on your application.
Secondly, reducing the FFT size results shorter processing time however smaller FFT size causes lower accuracy.
Reducing number of samples results shorter measurement time and shorter processing time. However changing number of samples affects accuracy and maximum range of the system.

Example Configuration:

Product	Configuration Description	Script
SiRad Easy® r4	AGC OFF, Gain 4, TL, ST and ERR 1, Protocol WebGUI ADC clk div set 1, number of samples 512, DC and WIN set 1, downsampling 0, FFT size 512	{!S11022F02} {!BA452C021}
SiRad Easy®	AGC OFF, Gain 3, TL, ST and ERR 1, Protocol WebGUI, ADC clk div 0, Number of samples 512, DC cancel, Window ON, Number of ramps 1, FFT size 512	{!BA452C020} {!S0100EE02}
SiRad Simple®	AGC OFF, Gain 3, TL, ST and ERR 1, Protocol WebGUI, ADC clk div 0, Number of samples 512, DC cancel, Window ON, Number of ramps 1, FFT size 512	{!BA452C020} {!S0100DE02}

How to adjust target detection

To improve your target detection, you can try the following:

• Make sure your target is inside of the maximum range of range spectrum
• See if your target is above the CFAR line, if not choose suitable CFAR and CFAR settings
• check if the target list is already full with the other 16 targets

How to increase accuracy

• Increase FFT size

Increasing FFT size increases the accuracy however, lowers the update rate.

• Decrease number of samples

Decreasing the number of samples increases the accuracy however, lowers the maximum range.

• Enable downsampling
• Increase bandwidth

Example Configuration:

Product	Configuration Description	Script
SiRad Easy® r4	Bandwidth: set maximum ADC clk div 2, Number of samples 256, Number of ramps16, down sampling 0, FFT size 2048, WIN and DC ON	{!BA452E11A}
SiRad Easy®	ADC clk div 5, Number of samples 256, Number of ramps16, down sampling 0, FFT size 2048, WIN and DC ON	{!BA452E11D}
SiRad Simple®	ADC clk div 5, Number of samples 256, Number of ramps16, down sampling 0, FFT size 2048, WIN and DC ON	{!BA452E11D}