CN-0507

Hi Sunnymaster,

Looking at other CN0507 inquiries, does this answer your question:

https://ez.analog.com/circuits_from_the_lab/f/q-a/542388/cn0507-vna-frequency-range

?

The serial protocol is described here:

https://wiki.analog.com/resources/eval/user-guides/circuits-from-the-lab/cn0507

This should give you a starting point for creating a new application.

-Mark

Hi，mthoren_adi,

The Return Values of cmd_normal in the Command List is ADC code. What does Reference voltage ADC code mean? How to process In-phase voltage ADC code, Quadrature voltage and Reference voltage ADC code into S-parameters or the same data format as other vector network analyzers?

Thanks

Hi Sunnymaster,

We've contacted the engineers that support this board for assistance.

-Mark

Hi sunnymaster,

The ADC codes are the unsigned integer measurements from the internal ADC of the ADuCM3029. The ADC has been configured to use an internal 2.5V as reference. To convert the ADC codes into the correct in-phase and quadrature voltages, follow the steps below:

1. Convert the ADC code into voltage:

   V_inphase = (Reference_inphase_ADC_Code) * 2.5 volts / (2^12)

   V_reference = (Reference_voltage_ADC_Code) * 2.5 volts / (2^12)

2. Remove the reference voltage from the measurement

   V_inphase_final = V_inphase - V_reference

The s-parameters could then be computed from the V_inphase_final and the V_quadrature_final as discussed here https://www.analog.com/media/en/reference-design-documentation/reference-designs/cn0507.pdf.

Regards,

edwinu

Hi sunnymaster,

The ADC codes are the unsigned integer measurements from the internal ADC of the ADuCM3029. The ADC has been configured to use an internal 2.5V as reference. To convert the ADC codes into the correct in-phase and quadrature voltages, follow the steps below:

1. Convert the ADC code into voltage:

   V_inphase = (Reference_inphase_ADC_Code) * 2.5 volts / (2^12)

   V_reference = (Reference_voltage_ADC_Code) * 2.5 volts / (2^12)

2. Remove the reference voltage from the measurement

   V_inphase_final = V_inphase - V_reference

The s-parameters could then be computed from the V_inphase_final and the V_quadrature_final as discussed here https://www.analog.com/media/en/reference-design-documentation/reference-designs/cn0507.pdf.

Regards,

edwinu

should be  V_inphase = (Inphase_voltage_ADC_Code) * 2.5 volts / (2^12)

Hi edwinu,

Thank you for your reply.I can get the V_inphase_final  and V_inphase_final V_quadrature_final, to get S11 I should do further processing. From https://www.analog.com/media/en/reference-design-documentation/reference-designs/cn0507.pdf. the S11 function can be writen as

S11=(Port1_receive_V_inphase_final + j Port1_receive_V_quadrature_final)/(Port1_forward_V_inphase_final + j Port1_forward_V_quadrature_final)

Is my understanding correct?

Thanks，

sunnymaster

By definition, it should be 

S11=(Port1_reverse_V_inphase_final + j Port1_reverse_V_quadrature_final)/(Port1_forward_V_inphase_final + j Port1_forward_V_quadrature_final)