[SOLVED] Noiise figure degradation while using Sensitivity Time control ( In RADAR receiver)

[shashy.br]

Hi all,

I am designing an X band receiver and i am going to implement STC (using Digital Attenuators),

I needed to know if the Noise figure should be maintained at a better level even when when applying the STC.

Because when i apply 30dB STC attenuation my receiver noise figure is degraded to abount 25 dB.

I thought that i need to decrease the power level of the nearby sources of reflection only ,

is this the way to implement STC ?

should i distribute my 30 dB attenuation over three different Digital attenuators to improve my noise figure?

:?:

 

[vfone]

Because STC in radar is used to avoid the saturation of the receiver by close in reflected signals (ground or nearby objects), the attenuators should be place to the front-end. The system automatically reduce this attenuation when receive long distance signals.

 

[shashy.br]

Thank you for the reply