LMX2572LP: Can both RF outputs be utilized at the same time for a doppler ranging application?

Andrew Loblaw

Part Number: LMX2572LP
Other Parts Discussed in Thread: LMX2572

I would like to use the LMX2572LP with a ramp profile for a doppler ranging application. Basically send a chirp signal out on a transmitter antenna, then demodulate the reflected/received signal with the original signal from the transmitter.

I can of course use a power splitter to do this, but there are already 2 channels on the LMX2572 (RFOUTA, RFOUTB) so I shouldn't need to split the power. Is there anything preventing me from using one of these channels for the transmit, and the other for the LO of a demodulator input?

Thank you in advance!

over 2 years ago

+1 Noel Fung over 2 years ago

TI__Guru* 81490 points

Hi Andrew,

Both outputs share the same input source - VCO. So if the VCO is ramping, both output signals are ramping. Frequency and phase of both outputs are also identical. Basically speaking, you can enable both outputs to get two identical copies.

0 Andrew Loblaw over 2 years ago in reply to Noel Fung

Prodigy 50 points

Ok great, thank you! Follow-on question still related to this - are there any caveats to using both outputs? e.g. Does it cause increased noise, spurs, or sidebands?

+1 Noel Fung over 2 years ago in reply to Andrew Loblaw

TI__Guru* 81490 points

Hi Andrew,

As far as I can remember, there is no performance degradation when both outputs are enabled.

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LMX2572LP: Can both RF outputs be utilized at the same time for a doppler ranging application?