What is "TWO-TONE SFDR" meaning?

[ermai]

https://www.analog.com/media/en/technical-documentation/data-sheets/AD9461.pdf

In the ADC datasheet , it depicts that

=======================================
TWO-TONE SFDR
fIN = 169.6 MHz @ 7dBFS, 170.6 MHz @ 7dBFS
=======================================

what is it meaning here?what is the explanation?

 

[pancho_hideboo]

In the ADC datasheet , it depicts that
=======================================
TWO-TONE SFDR
fIN = 169.6 MHz @ 7dBFS, 170.6 MHz @ 7dBFS
=======================================

Wrong.
Surely read data sheet before posting.

See Figure-23.
Spurious_Level<=-89dBFS for f1=169.6MHz@-7dBFS and f2=170.6MHz@-7dBFS.

Fs=130MHz
UnderSampling.

 

[ermai]

Wrong.
Surely read data sheet before posting.

See Figure-23.
Spurious_Level<=-89dBFS for f1=169.6MHz@-7dBFS and f2=170.6MHz@-7dBFS.

Fs=130MHz
UnderSampling.

Thanks.So it deduces that the f1=169.6MHz@-7dBFS and f2=170.6MHz@-7dBFS. produce the noise pattern in figure 23 under Fs=130MHz?
But if the Fs=130MHz, then the image should be located at 2x130Mhz -170.6Mhz=89.4Mhz, however in figure 23 , the -7dB is at between 31.250 - 46.875Mhz, I can't figure it out.

here is illustration of my comprehension
https://i.imgur.com/xSnYi1t.png

 

[pancho_hideboo]

Can you understand undersampling or subsampling ?

 

[ermai]

Can you understand undersampling or subsampling ?

https://imgur.com/a/08deP
I figured it out !!!It is from the image of negative fs !!!

 

[pancho_hideboo]

I figured it out !!!It is from the image of negative fs !!!

Before posting, learn very basic things surely.