01-27-2013 11:55 PM
I'm trying use NI PXI-5650 RF Signal Generator to generate on-off-keying modulated signal on 1090 MHz. But, as described on Page 14 of NI PXI-5650/5651/5652 Specifications I can operate from –9.5 to 10 dBm when using this modulation type. I'm looking for the most rational and affordable way to achieve amplitude range down to -100 dBm. Attenuator maybe? Or some third-party generator? For PXI, not PXI-e.
01-28-2013 02:17 PM - edited 01-28-2013 02:17 PM
Jrbn,
Typically you would send the signal to an external attenuator like the PXI 5695
http://sine.ni.com/nips/cds/view/p/lang/en/nid/207936
As you can probably see, this offers 60dB of attentuation. To achieve 100dBm you would need two. 100dB is a lot of attentuation. Keep in mind, at these levels, you are entering the realm where noise may pose a lot of challenges. What exactly are you trying to accomplish?
(I can't speak for 3rd party products, I'm not familiar with their capablilies.)
Regards,
01-29-2013 09:09 PM
Just what I thought.
I'm trying to simulate ADS-B signals to test sensitivity of a receiver. Currently I use High-Speed Digital I/O and some big old RF generator for modulation and attenuation. I think I'll keep using this configuration then. Thanks anyway.