AWR1243: Fc meaning in SNR calculation formula

Wesley He

Part Number: AWR1243

Hi team,

My customer is curious about Fc meaning in SNR calculation formula from document: Programming Chirp Parameters in TI Radar Devices

Could anyone point out the meaning of this value?

Thanks.

Regards,

Wesley

over 6 years ago

0 Anand Gadiyar over 6 years ago

TI__Genius 14815 points

This formula is derived from the Friis transmission equation (en.wikipedia.org/.../Friis_transmission_equation).

Fc is the transmitted wave frequency.

(Alternatively, you can consider ((c^2)/(Fc^2)) in the above formula as the square of the RF wavelength.)

0 rongjiang liu over 6 years ago in reply to Anand Gadiyar

Expert 1275 points

For a chirp, the start and end frequency of the chirp may be quite different,

so Fc means the start frequency or the end frequency, or Fc =(the start frequency + the end frequency) /2?

In other words, what's the value of Fc when I calculate the parameter?

Regards

0 rongjiang liu over 6 years ago in reply to Anand Gadiyar

Expert 1275 points

In reply to Anand Gadiyar:

For a chirp, the start and end frequency of the chirp may be quite different,

so Fc means the start frequency or the end frequency, or Fc =(the start frequency + the end frequency) /2?

In other words, what's the value of Fc when I calculate the parameter?

Regards

0 rongjiang liu over 6 years ago in reply to Anand Gadiyar

Expert 1275 points

hi, Anand, can you answer the question?

0 Anand Gadiyar over 6 years ago in reply to rongjiang liu

TI__Genius 14815 points

Hi,

You can use the center frequency of the chirp as a good approximation. So Fc = (start frequency + end frequency) /2 is okay to use.

Best Regards,
Anand

0 rongjiang liu over 6 years ago in reply to Anand Gadiyar

Expert 1275 points

thanks
good reply

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AWR1243: Fc meaning in SNR calculation formula