In order to get Phase alignment in a normal fashion, circuitry has to be in place to share the Local oscillator on the RF up and down convert chain. The X410 is able to use a common 10MHz reference for all ADC/DACs which would also be required for a truly phase coherent application. The USRP X410 doesn't have that LO sharing capability built in, The USRP N320 & USRP N321 was built with this circuitry by default.
Depending on the performance you need we actually built a full multi-channel phase coherent reference architecture on the USRP N320/N321, you can learn more about that here. https://www.ni.com/en-us/solutions/aerospace-defense/radar-electronic-warfare-sigint/radar-ew-research-prototyping/build-radar-ew-testbeds.html Back to your X410 question, I believe there is a way to lock each channel on the X410 to the 10MHZ frequency reference such that there is no frequency difference channel to channel on the LO. However, that doesn't guarantee a fixed phase difference channel to channel on each initialization, I believe the SDR Product Engineering team was looking at ways to mitigate that uncertainty through a shared digital reset, I've forwarded this question to our product management team to respond with more details into that research project, which is what I was referring to on the notes you found on Ettus.com 😊 With that said, if you are looking for more than 4 channels (IE more than 1x X410 radio) that might get difficult but we can have that conversation to see what is possible, the USRP N320/N321 is the recommended radio currently for such system configurations currently. Hopefully that helps. Haydn Nelson Principal Solutions Marketing Manager Wireless/Radar/EW & EOIR Test Solutions Aerospace and Defense +1-512-731-7251 | ni.com -----Original Message----- From: Marcus D. Leech <patchvonbr...@gmail.com> Sent: Monday, May 16, 2022 9:11 AM To: usrp-users@lists.ettus.com Subject: [EXTERNAL] [USRP-users] Re: Does X410 support phase-aligned and phase-corent? On 2022-05-16 04:17, Mikio Fukushima wrote: > Hi all, > I'm considering to purchase a USRP X410 for one of research projects. > the objective of this project is MIMO operation, I have some questions. > > Q1. > Does each channel on X410 support phase-aligned and phase-corent > operation? It isn't meaningful to consider phase-coherence and phase-alignment on a single channel. The phase-coherence and alignment is always with respect to other channels. > > Q2. > Does each channel on multi X410s support phase-aligned and > phase-corent operation? > > Q3. > What is "Limited performance"? > > [3] Limited performance four-channel phase-coherent operation within a > single radio is under investigation I'm not sure what "limited performance" means, nor what the schedule for that is, but I know that in initial release, the X410 does NOT support mutual phase-coherence even within a single radio. > > https://urldefense.com/v3/__https://www.ettus.com/all-products/usrp-x410/__;!!FbZ0ZwI3Qg!qK9xBuKBWusDewCqTkeFl1SjAew_36nFIxqesMafqOGheMElwp5DK15Ie-TLiYI6NBKQgznYDfh0DZ1WtHDYug$ > > _______________________________________________ > USRP-users mailing list -- usrp-users@lists.ettus.com > To unsubscribe send an email to usrp-users-le...@lists.ettus.com _______________________________________________ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com INTERNAL - NI CONFIDENTIAL _______________________________________________ USRP-users mailing list -- usrp-users@lists.ettus.com To unsubscribe send an email to usrp-users-le...@lists.ettus.com
