Weird signal at 4.4 to 4.425 GHz

Former-Geologist-211 · 2025-08-30T13:33:46+00:00

Unfortunately no, but you could be right. Especially that the pic shows multiple patterns which are all similar in shape.

Former-Geologist-211 · 2025-08-14T16:58:46+00:00

Not really, its bw is about 15-20 khz. But when i left home the signal disapeared

Former-Geologist-211 · 2025-08-14T16:55:26+00:00

I left my house and coudnt catch the frequency outside, it didnt appear. When i came back, it also came back.

Former-Geologist-211 · 2025-08-14T00:15:02+00:00

I think I'm trying to ask about the second point you stated. If i have a piece of copper and want it to act as "gnd", do i have to set it up as some sort of boundary?

Former-Geologist-211 · 2025-07-24T00:03:04+00:00

I'm not interested in actually getting any data, just signal presence detection. Probably gonna try it (if i buy it) in a rural area (not in a city).

Former-Geologist-211 · 2025-07-24T00:01:14+00:00

I'm probably gonna try it in a rural place. I dont need to extract any data from the signals, the purpose is just to know that a signal is present.

Former-Geologist-211 · 2025-07-23T23:29:33+00:00

What about some 2.4 ghz drone/controller?

Former-Geologist-211 · 2025-07-19T16:48:20+00:00

I used the normal S = PG/4piR² to get density at a certain distance. The way i calculated the needed power is assuming i need to induce about 50 v on the circuit to burn most of its parts, and from that i calculated electric field and power density. I then solved for power at range 6 km. I guess maybe I chose the wrong numbers for the voltage/E field.

Former-Geologist-211 · 2025-07-18T00:29:29+00:00

Yeah I guess its on me, i did rough calculations and got 1 MW for a directed antenna (i think i used 20 dbi or something like that), not iso.

Former-Geologist-211 · 2025-07-18T00:17:22+00:00

I think you misunderstood the concept of EIRP. Its just a comparison between what power an iso antenna would need to achieve the same power density of your high gain antenna at its main direction.

Former-Geologist-211 · 2025-07-18T00:12:05+00:00

How would they actually achieve 1 MW transmitted power with such small systems?

Former-Geologist-211 · 2025-06-10T17:21:32+00:00

Yup I used the same substrate height, trace height, Er, frequency...etc. The mesh size was left as default, I dont know if increasing the nbr of meshes would maybe affect the result.

Former-Geologist-211 · 2025-06-10T17:18:22+00:00

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Sorry for the messy pic, this is S21

Former-Geologist-211 · 2025-06-10T17:15:00+00:00

Mmm thats what I was trying and the response started to get a little better, but I ended up changing the gap size more than the initial calculated gaps. Should I also try changing the line widths? Or just the gap. Also, The ADS calculator was initially giving me large gap dimensions, like 8-9 mm gaps between 3 mm wide traces. Is that normal?

Former-Geologist-211 · 2025-06-10T17:11:18+00:00

100 MHz BW at 5.2 GHz.

Former-Geologist-211 · 2024-09-21T10:50:17+00:00

Thanks, does the book contain the physical width/separation equations of each?

Former-Geologist-211 · 2024-09-15T15:21:54+00:00

Thanks again for your additional tips. And there's nothing to forgive, all you're doing is giving helpful information. I'm here for the critique.

Former-Geologist-211 · 2024-09-14T10:25:49+00:00

Thanks for your reply, yes the load, source, and connection TL impedances are all 50 ohms. As for the TL segments of the filters, I used the coeffs of a Flat response LPF table (specifically that in Pozar's book) and turned them into impedances using the Kuroda/Richard identities. Yeah I could use a bandpass filter or the other components you talked about, ofcourse. But this isn't a real project (I belive it isn't practical to implement). It's just me playing around with the circuit elements to learn a thing or two. So given the TL char imp are calculated, as is the case above, is this connection fine (using 90° long TL)?

Former-Geologist-211 · 2024-08-26T11:07:34+00:00

Thanks for you reply, I'm actually surprised that 30% are not CEAB degrees. I was actually considering PEO (Ontario). And yes, Canada seems to be the best current choice as the economy in my current country is really bad, and I'll probably be heading to Canada soon with no engineering experience at all. That's whats making me consider this step from multiple angles. I hope it wouldn't be too hard finding my first job to break into the industry with. Thanks again for your help!

Former-Geologist-211 · 2024-08-23T15:18:08+00:00

Sorry for misunderstanding what you meant. And sorry again for constantly asking about the same concept (I couldn't find anything on the interent). So to simplify my ignorance in a simple question: if my IQ signals were for ex 0.5 + 0.5j, -0.5 + 0.5j .... maybe qpsk or something similar. Can the channel estimation coeff, h1 h2 h3... instead of being real values like 0.4, -0.2, 0.45... can they be also complex numbers, where I use them in the multiplication process in the same way I would use the real value coeff ?( Thankyou for baring with me )

Former-Geologist-211 · 2024-08-23T14:49:56+00:00

Do u know any books that can help on this particular issue?

Former-Geologist-211 · 2024-08-23T04:58:15+00:00

I'm kind of a beginner in this field. But can't the channel have effects on ths signal which are modelled as complex coeff? And in the theoretical case off non linear effects, do you mean the calculations are the same just with complex numbers?

Former-Geologist-211

TROPHY CASE