r/rfelectronics 17h ago

question Designing a Waveguide Adapter

Post image
8 Upvotes

Hi, I'm currently working on a hobby project with a large prime focus satellite dish, that I can't get a feedhorn for. Making the feedhorn isn't a problem but connecting it to the LNB is a bit more difficult. I need to make an adapter to go from an odd diametre to a WR-75 compatible mount for the Ku-Band LNB.

I drew two versions of the same adapter in CAD and I'm wondering which one would be better? The top one uses tangential swep-blend avoiding discontinuity, and the other one is much simpler using just a linear transition. The linear one is of cause much easier to manufacture than the tangential one.

Which one should I go for? Would they perform the same or would this create impedance problems or reflactions or high attenuation? I'm a mechanical engineer, not a RF engineer so this is more like magic to me at this point to be honest.


r/rfelectronics 1h ago

PhD in Phased Arrays, stuck in an RF Frontend role. Am I pigeonholing myself away from Antenna Design?

Upvotes

Hi everyone,

I’m facing a bit of a career dilemma and would love some perspective from senior engineers in the industry.

To give you some background, I finished my PhD 3 years ago at a European university. My dissertation focused on developing large phased array antennas—mostly EM simulation, radiator design, and that side of things. During my PhD, I closely collaborated with a local defense contractor, and I really wanted to join them as an employee after graduating. My supervisors from the company even recommended me to the head of the antenna group. However, despite holding Western European citizenship, my non-EU birth and early childhood background triggered strict security clearance roadblocks, so they couldn't offer me a position.

Right after my PhD, I joined a commercial satellite company where I have been working for the last 3 years. I'm currently a Senior RF Engineer, working on a massive project developing a multi-thousand-element phased array. Despite my PhD focusing on antenna radiators, I also had a solid grasp of RF electronics fundamentals and a strong interest in the field. Because of that, my manager put me on the RF frontend design team so I could bridge the hardware and antenna domains. We already have a dedicated, veteran antenna engineer handling the radiator design, and because the project is in full swing, management won't move me to a different role in the middle of it. In my current role, I work as a frontend design engineer while also supervising, mentoring, and guiding two junior RF engineers.

While the work is interesting, my day-to-day is almost entirely RF electronics. I really miss the core EM and radiator design work I did during my PhD, which is what I actually find fulfilling. My manager has promised to consider transitioning me to an antenna role once this current project phase wraps up in next 3-4 years, but I'm starting to worry about my long-term positioning.

A few specific things are on my mind:

First, if I stay here working on the frontend for another 3-4 years, am I going to get permanently pigeonholed as an "RF Engineer"? I'm worried it will get harder and harder to pivot back to core antenna array design the longer I stay away from it.

Second, does system scale matter more than the exact role type? Is it better for my resume to stay on a highly complex, massive array project even if I'm on the frontend side, or should I jump ship to a company designing smaller, simpler antennas just to get back into core EM design?

Third, given my current title, if I try to move over to a pure antenna role at a new company, will I be forced to take a step back to a mid-level or junior role because my recent industry experience is on the frontend? Or does the combination of a phased-array PhD and senior system-level experience carry over to a senior antenna position?

Finally, the European market feels a bit restrictive. Because of my security clearance limitations, I have to stick entirely to the civil/commercial sector (commercial aerospace, satcom, or telecom).

Are there any specific companies or commercial hubs you would recommend targeting in Europe that work on ultra-large phased array designs but operate purely in the civil domain? And for anyone who has made a similar pivot—how do hiring managers view frontend work on a massive phased array versus basic radiator design for smaller antennas?

Thanks in advance for any insights or advice you can share!

(Note: This post was written by me with the help of AI to protect anonymity and organize my thoughts clearly.)


r/rfelectronics 18h ago

[update] In a previous post I asked what is wrong with my circuit, I listened and changed some things.

Thumbnail
gallery
5 Upvotes

It no works, not sure exactly why? And why the frequency is way off than what it should be (around 2 MHz) but hey something is always better than nothing.

Edit: I think I flipped c1 and c2 in the diagram.


r/rfelectronics 7h ago

CST Student to Commercial

3 Upvotes

so i made my antenna in student license but while simulating i got hit by the mesh limit, so i wanted to simulate it in a licensed version in my college desktops but apparently student version files cannot be opened in the commercial version. Any workaround to convert or do i just have to recreate again in the commercial version??


r/rfelectronics 7h ago

RF Engineering Channel

Thumbnail
0 Upvotes

r/rfelectronics 16h ago

5G tower concern.

0 Upvotes

Thinking about moving to a property. Upon inspecting it, there was a 5G tower nearby. Measuring the distance- it is abut 125 meters to edge of property and about 135 to the building. Looking at some case reports, someone had health problems living 125 meters away.

https://ehtrust.org/7-scientific-case-reports-on-5g-cell-tower-health-impacts/

I measured the RF exposure, walking around with a GQ EMF-390 3-in-1 EMF/ELF/RF Meter. There was nothing from the distance of 200 meters, there was nothing as I approached it and nothing underneath it. (Nothing as in higher than 200 uW/m2. Once, it peaked to 6000 uW/m2 but swiftly disappeared. This was 10 yards away from the 5G tower. The tower looks like a cylinder mounted to the top of the pole with a few "small cells" boxes. I am thinking now, that the tower operates above 10Ghz. My device can only see up to 10Ghz. I can measure "regular" 4G towers hundreds of meters away.

What do you all think about this?

How prevalent are the above 10Ghz towers at this time? I understand the higher the frequency, the lower the range of the signal. The property is also semi-blocked by some heavy trees. That should block some of that off as well, right?

I traveled to another tower and almost the same thing happened. Now, it seems that the device picked up the "3 brown boxes" towers on the top of the poles, though. Perhaps, they are still operating in the lower frequencies.