SOLVED! The 5G Challenge and solutions

The problem has been solved!

B52

Member
Original poster
May 14, 2009
10
5
Asia
In Australia 5G rollout started in August last year at 3650 MHz, the harmonics affected the whole C band spectrum ... the result is pixelation and video dropouts or no signal. Since then a few affordable solutions have come it the market. LNB's with a built in filter at the front end before amplification and downconversion. They are available in single or dual outputs.
5G_LNB.jpg
 
Interference has been expected all along. That's why there has long been a plan to use proceeds from the FCC's C-band spectrum auction to provide free filters to every C-band satellite dish that was registered with the FCC before the 2018 registration cutoff date.
 
Interference has been expected all along. That's why there has long been a plan to use proceeds from the FCC's C-band spectrum auction to provide free filters to every C-band satellite dish that was registered with the FCC before the 2018 registration cutoff date.
If they auction off the spectrum...wouldn't that limit the usability of the dish?.. i guess it depends how much gets shifted to another use
 
If they auction off the spectrum...wouldn't that limit the usability of the dish?.. i guess it depends how much gets shifted to another use
280 MHz of the 500 MHz of spectrum dedicated to C-band satellite downlink in the contiguous United States is being auctioned off (beginning in about 24 hours, incidently).

There will be an additional 20 MHz guard band between the auctioned off spectrum and the spectrum that remains for satellite.

So, when all is said and done, all C-band satellite signals targeted toward the contiguous United States will have 200 MHz of spectrum remaining. This is a sufficient amount to accommodate the existing signals, but new satellites had to be ordered and some video signals have to move to more efficient HEVC compression. The entire process has been several years in the making.

If you're wondering about what's going to happen to the corresponding C-band uplink spectrum, that's being turned over to unlincesed use, including WiFi.
 
If that is what the freq spectrum looks like with 5G, I don't see how a filter would eliminate the interference since the noise would fall within the passband of the filter.
 
kofi133,

I understood that any interference above the alotted specturm would be minimal at best.
Guess I misread..

John

Without a bandpass filter, out of target frequency interference "swamps" the conversion or receiver's front end. The filter attenuation should be -60 to -70dB to allow the bandpass frequencies to be received without interference. Our preproduction sample testing has be highly successful at eliminating the interference within the reduced C-band frequency range with only a 20MHz band edge.

As a side note, we have been distributing filtered PLL LNBFs since 2013. The C1-PLL attenuation level and range was found not to be effective against the recent "5G" terrestrial launch, but the C2-PLL bandpass range and attenuation has been very effective.

We will be introducing several new filtered LNBFs models for the upcoming reduced North American ranges as they are implemented in stages over the next three years. At this time, there is no "5G" interference with the C-band range in North America. Expect this interference source to start to become a potential problem in 2022.
 
I hope these 5G filtered C-band lnbf's aren't going to cost much more than they are now.
 
I hope these 5G filtered C-band lnbf's aren't going to cost much more than they are now.

It will hurt a bit financially to replace 'good' lnbfs when the time comes. Based on past experience, I have confidence that Titanium Satellite will offer a good product at a reasonable price.

Just part of keeping a system working I guess.
 
In Australia 5G rollout started in August last year at 3650 MHz, the harmonics affected the whole C band spectrum ... the result is pixelation and video dropouts or no signal. Since then a few affordable solutions have come it the market. LNB's with a built in filter at the front end before amplification and downconversion. They are available in single or dual outputs.View attachment 149222

Show us more about those 5G scalar rings. I've seen a little discussion on those from a satellite hobby group from Latin America. They apparently have helped improve SNR a little bit without having to change out LNBFs or feedhorns. I looked them up on ebay au but they are pricey with shipping to the states.
 
Without a bandpass filter, out of target frequency interference "swamps" the conversion or receiver's front end. The filter attenuation should be -60 to -70dB to allow the bandpass frequencies to be received without interference. Our preproduction sample testing has be highly successful at eliminating the interference within the reduced C-band frequency range with only a 20MHz band edge.

As a side note, we have been distributing filtered PLL LNBFs since 2013. The C1-PLL attenuation level and range was found not to be effective against the recent "5G" terrestrial launch, but the C2-PLL bandpass range and attenuation has been very effective.

We will be introducing several new filtered LNBFs models for the upcoming reduced North American ranges as they are implemented in stages over the next three years. At this time, there is no "5G" interference with the C-band range in North America. Expect this interference source to start to become a potential problem in 2022.

Thanks for the update how can I if I have a PLL-1 or a PLL -2?
 
I've dealt with a lot of C-band interference problems and out of band signals from marine radar and aircraft altimeter radar will saturate the amplifiers in an LNB or LNA eating up all the available output power and gain causing received signals to be pushed way down in level and the noise floor to go through the roof. 5G has the potential to wreak havoc on existing C-band systems even with older type "radar" filters because 5G is in band and at frequencies that we used to receive off satellites.

The needed effectiveness of a new 5G filter will depend on the proximity and direction of the 5G source to your dish and LNB. One of my companies facilities with lots of C-band dishes was near a major airport and the off the shelf Microwave Associates 3.7 to 4.2GHz wave guide filters were not good enough to reliably keep out aircraft altimeter radar, so very expensive filters were purchased from Apollo Microwave in Canada. I don't remember the exact price but I think they were in the $1.2k range and we got a discount because we purchased a lot of them. They were well over a foot long and caused some mechanical mounting challenges.

When 5G fires up there will be massive problems for naked LNBs with no filters or with existing radar filters and you might purchase a 5G filter now and find a new 5G transmitter site gets built out right in front of your dish later that trashes your reception, requiring a new very elaborate and expensive filter.
 
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Returning back to one of the ways we used to block or attenuate terrestrial interference to C-band systems from the telephone companies in the 80s... Place the dish behind a structure to attenuate the interfering signals. Used to use steel pole barns, garages, homes and even erect checken wite or hardware cloth as effective RF walls to block telco (microwave) PTP interference.

I agree. In North America, do not buy a filter or move the dish, yet. Wait to see if or what interference affects your reception . This way you will know the direction of the signal(s), the frequency of the interferring signal(s) then develop a plan to mitigate. You may decide to purchase an intermediate filtering solution during the frequency transition or wait until all frequency transitions have been completed. The transitions will happen in two phases and transponders may remain active in the two current lower frequency divisions. Some locations will not be affected at all. Wait and see...
 
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Returning back to one of the ways we used to block or attenuate terrestrial interference to C-band systems from the telephone companies in the 80s... Place the dish behind a structure to attenuate the interfering signals. Used to use steel pole barns, garages, homes and even erect checken wite or hardware cloth as effective RF walls to block telco (microwave) PTP interference.

I agree. In North America, do not buy a filter or move the dish, yet. Wait to see if or what interference affects your reception . This way you will know the direction of the signal(s), the frequency of the interferring signal(s) then develop a plan to mitigate. You may decide to purchase an intermediate filtering solution during the frequency transition or wait until all frequency transitions have been completed. The transitions will happen in two phases and transponders may remain active in the two current lower frequency divisions. Some locations will not be affected at all. Wait and see...
Chicken wire would look crummy and I know the wife won't like it and quite possibly the neighbors. Relocating the antenna would be a major issue also. Leave it to the government to screw things up. But, I might be one of the lucky ones that won't have these issues. :rain
 
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