3 ms·

Fun facts, you can build your own VNA from scratch using open source GNU Radio toolkit with any off-the-shelf SDR platform for example using the low-cost ADALM-

Fun facts, you can build your own VNA from scratch using open source GNU Radio toolkit with any off-the-shelf SDR platform for example using the low-cost ADALM-Pluto or you can go fully gung ho with the more capable RFSoC platform [1],[2],[3],[4]: [1] Lab notebook of experiments in GNURadio: http://www.swigerco.com/gnuradio/ http://www.swigerco.com/gnuradio/ [2] Off-the-Shelf Reconfigurable Software Define Radio Approach for Vector Network Analyzer: https://jati.apu.edu.my/files/2018/12/2018_Issue2_Paper1.pdf https://jati.apu.edu.my/files/2018/12/2018_Issue2_Paper1.pdf [3] ADALM-PLUTO: Software-Defined Radio Active Learning Module (USD230): https://www.analog.com/en/resources/evaluation-hardware-and-software/evaluation-boards-kits/adalm-pluto.html https://www.analog.com/en/resources/evaluation-hardware-and-... [4] RFSoC 4x2 Development Kit Overview (USD2K): https://news.ycombinator.com/item?id=39427825 https://news.ycombinator.com/item?id=39427825

megous 3y ago
> or you can go fully gung ho with the more capable RFSoC platform You can't: > The RFSOC 4x2 is currently only available to staff at accredited Universities and Research Institutes.
- haneefmubarak 3y ago
  If you go to the Real Digital site (vendor that makes the board), they appear to also sell it commercially, albeit at the higher price of ~$4k (compared to their academic pricing of ~$2k).
stephen_g 3y ago
Wow, that RFSoC board is incredibly cheap - ours cost $12K or so, and we needed special approval too under defence regulations.
jdewerd 3y ago
VNAs are fundamentally narrow-band instruments. This: > The RFsoC 4x2 board has 4x RF ADCs (5 GSPS) and 2x RF DACs (9.85 GSPS) is like chasing after a fly with a sledgehammer. It wildly over-specs something that is almost completely useless for the task at hand (real time bandwidth, mass of hammer) while it wildly under-specs the important parts (frequency range, directivity, agility of hammer).
- teleforce 3y ago
  If you have the RFSoC the VNA is the low hanging fruit. If you're doing modern wireless systems measurement and testing (4G/5G) most likely you will need spectrum analyzer (SA), vector signal analyzer (VSA) and vector signal generator (VSG). The cost of all the disparate systems namely VNA + SA + VSA + VSG will easily cost north of USD100K for the used ones and multiple times more for the new ones. With the low cost RFSoC platform together with the standard RF test kit (attenuater, pre-amp, multiplexer, switch, etc) you are pretty good to go. It's really perplexing that no one including the Chinese are trying to disrupt this industry, Keysight and R&S are currently charging arms and legs for their equipments even the basic one like VNA.
  - bsder 3y ago
    > It's really perplexing that no one including the Chinese are trying to disrupt this industry No point. 1) Low volumes These things never really go obsolete and the replacement rates are abysmal. 2) Race to the bottom Once you disrupt it, everybody sees that you disrupted it, and everybody clones you and piles in. Customer support is the only differentiator. To fund that, you have to charge north of $10K per unit--generally north of $25K. Tektronix found this out the hard way with their real time spectrum analyzers. It was a nice disruption at the $5K point. Lots of people bought them. Then demand dropped like a rock because everybody who needed one bought one. And because the revenue crashed Tektronix laid off the development group--who are also the same people you need for advanced customer support.
  - sitzkrieg 3y ago
    siglent is moving in on VNAs a bit but i absolutely agree. as a ham i could do with all of above :-)
rasz 3y ago
>low-cost ADALM-Pluto ~$250, meanwhile Chinese nanoVNA clones are ~$25-40, add prescaler and you can reach 6GHz. Anecdotally I have seen nanoVNAs being used with directional antennas in Ukraine as crude drone finders. https://www.reddit.com/r/CombatFootage/comments/1afspa8/combat_work_of_antiaircraft_guns_of_the_47th/ https://www.reddit.com/r/CombatFootage/comments/1afspa8/comb...
- blackfawn 3y ago
  Very late reply but that is most likely a tinySA, a compact and inexpensive spectrum analyzer that uses the same case as many nanoVNAs: https://www.tinysa.org/ https://www.tinysa.org/

megous 3y ago

> or you can go fully gung ho with the more capable RFSoC platform You can't: > The RFSOC 4x2 is currently only available to staff at accredited Universities and Research Institutes.

haneefmubarak 3y ago
If you go to the Real Digital site (vendor that makes the board), they appear to also sell it commercially, albeit at the higher price of ~$4k (compared to their academic pricing of ~$2k).

stephen_g 3y ago

Wow, that RFSoC board is incredibly cheap - ours cost $12K or so, and we needed special approval too under defence regulations.

jdewerd 3y ago

VNAs are fundamentally narrow-band instruments. This: > The RFsoC 4x2 board has 4x RF ADCs (5 GSPS) and 2x RF DACs (9.85 GSPS) is like chasing after a fly with a sledgehammer. It wildly over-specs something that is almost completely useless for the task at hand (real time bandwidth, mass of hammer) while it wildly under-specs the important parts (frequency range, directivity, agility of hammer).

teleforce 3y ago
If you have the RFSoC the VNA is the low hanging fruit. If you're doing modern wireless systems measurement and testing (4G/5G) most likely you will need spectrum analyzer (SA), vector signal analyzer (VSA) and vector signal generator (VSG). The cost of all the disparate systems namely VNA + SA + VSA + VSG will easily cost north of USD100K for the used ones and multiple times more for the new ones. With the low cost RFSoC platform together with the standard RF test kit (attenuater, pre-amp, multiplexer, switch, etc) you are pretty good to go. It's really perplexing that no one including the Chinese are trying to disrupt this industry, Keysight and R&S are currently charging arms and legs for their equipments even the basic one like VNA.
- bsder 3y ago
  > It's really perplexing that no one including the Chinese are trying to disrupt this industry No point. 1) Low volumes These things never really go obsolete and the replacement rates are abysmal. 2) Race to the bottom Once you disrupt it, everybody sees that you disrupted it, and everybody clones you and piles in. Customer support is the only differentiator. To fund that, you have to charge north of $10K per unit--generally north of $25K. Tektronix found this out the hard way with their real time spectrum analyzers. It was a nice disruption at the $5K point. Lots of people bought them. Then demand dropped like a rock because everybody who needed one bought one. And because the revenue crashed Tektronix laid off the development group--who are also the same people you need for advanced customer support.
- sitzkrieg 3y ago
  siglent is moving in on VNAs a bit but i absolutely agree. as a ham i could do with all of above :-)

rasz 3y ago

>low-cost ADALM-Pluto ~$250, meanwhile Chinese nanoVNA clones are ~$25-40, add prescaler and you can reach 6GHz. Anecdotally I have seen nanoVNAs being used with directional antennas in Ukraine as crude drone finders. https://www.reddit.com/r/CombatFootage/comments/1afspa8/combat_work_of_antiaircraft_guns_of_the_47th/ https://www.reddit.com/r/CombatFootage/comments/1afspa8/comb...

blackfawn 3y ago
Very late reply but that is most likely a tinySA, a compact and inexpensive spectrum analyzer that uses the same case as many nanoVNAs: https://www.tinysa.org/ https://www.tinysa.org/