Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Is it possible to recover a 1pWatt signal?

Status
Not open for further replies.

Mr.Cool

Advanced Member level 2
Joined
Jun 20, 2001
Messages
664
Helped
87
Reputation
178
Reaction score
60
Trophy points
1,308
Activity points
7,113
boselec.com/products/siglimwhat.shtml

Does anyone know how, or can point to useful reading material, to recover a signal that has at most 1pWatt of power?

at this low of a level i expect the signal (from a CCD camera) to be burried in noise. any suggestion would be helpful

regards

Mr.Cool
 

Mr.Cool

Advanced Member level 2
Joined
Jun 20, 2001
Messages
664
Helped
87
Reputation
178
Reaction score
60
Trophy points
1,308
Activity points
7,113
could use an amplifier and filter , amplifier and filter, etc. to get the signal up to a useable level.

but it would still be lost in noise...

Mr.Cool
 

FANT

Advanced Member level 1
Joined
Feb 27, 2002
Messages
415
Helped
52
Reputation
104
Reaction score
37
Trophy points
1,308
Location
Italy
Activity points
3,652
Difficult

Consider a bandwidth of 5 MHz, this means a noise at the input of the amplifier of -100dBm ( - 174 + [( 20log(10) BW ( 5 MHZ)=74 dB] this with an amplifier with no imput noise figure ( 0dB); 1 pW means - 90 dBm and at the end this means you have only 10 dB S/N at the input of the amplifier.
Considering a noise figure of the amplifier of 2 dB you have at the output of the amplifier a S/N of merely 8 dB, to my experience not enough to view nothing but noise.

Mandi
 

Mr.Cool

Advanced Member level 2
Joined
Jun 20, 2001
Messages
664
Helped
87
Reputation
178
Reaction score
60
Trophy points
1,308
Activity points
7,113
unfortunately i need to know if its possible by today! because i must make a decision weither to accept this project or not.

can we take a poll... all in favour?
 

RegUser_2

Full Member level 2
Joined
Dec 24, 2001
Messages
125
Helped
11
Reputation
22
Reaction score
9
Trophy points
1,298
Activity points
1,507
Depend on the sensor and on the signal bandwidth. For instance the modern bolometric receivers have noise equivalent power of 1E-17 watt/RtHz and signal bandwidth several khz. Of corse you need to cool this thing to 0.3K though, but the 1 pW will be resolved with a signal to noise ratio of 1000 ;)
 

FANT

Advanced Member level 1
Joined
Feb 27, 2002
Messages
415
Helped
52
Reputation
104
Reaction score
37
Trophy points
1,308
Location
Italy
Activity points
3,652
recovered signal

Yes, looks that with an amplifier cooled is possible to obtain a very low noise figure, but to me seems that the person needs a video amplifier for a video signal ( 5 MHz bandwidth ) and not some tens of KHz, probably it has not to cost too much and possible to build with normal components ( possibly RS for the prototype ); this is the real world.
On the other side if you need a very special amplifier with such characteristics seem to me that an engineer needs more than some days to say if he can accept or not the project and on the other side, before the decision, there is for sure ( unless someone don't want to suicide ) a study for the possibility to build such amplifier or even all the system.
Nobody is so crazy to accept a so complicated project without a preliminary study about feasibility.
 

Mr.Cool

Advanced Member level 2
Joined
Jun 20, 2001
Messages
664
Helped
87
Reputation
178
Reaction score
60
Trophy points
1,308
Activity points
7,113
agreed. i had only 3 days to decide. in the end i did not feel confident that it could be accomplished easily (even with a big $ budget and lots of time). i have decided to persue a venture in renewable energy instead.

thanks for all your advice

Mr.Cool
 

Jackal

Member level 2
Joined
Sep 25, 2002
Messages
45
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Location
Russia, Krasnodar
Activity points
288
Hi!

I think you may to try SHF components from Mini-Circuits it's very low noise... Also i think that correct recovery of 5Mhz bandwidth signal with this power, are really but only with digital video processing.

Regards, Jackal.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top