Nice I will have to check into that. As soon as you test your LNA let me know what the results are. I am leaning toward building my own receiver for 1.6-1.7 Ghz using this design "antenna -> LNA -> I/Q Demodulator (ADRF2820) -> BPSK Demodulator (FPGA)-> USB controller"
Smallest EMWIN antenna
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Got my LNA today - won't have time to play with it until this afternoon.
Dish wise i think we're ok - same dish as commercial systems. feedhorn / receiver wise is a different story.
I think demodulation / decoding of the signal can be done in GNURADIO.
References:
http://wernerlabsinc.com/files/Antenna assembly.pdf
http://www.goes-r.gov/hrit_emwin/ATR-2010-5482.pdf
Have you tried to get a usable signal out of your antenna yet?
Dish wise i think we're ok - same dish as commercial systems. feedhorn / receiver wise is a different story.
I think demodulation / decoding of the signal can be done in GNURADIO.
References:
http://wernerlabsinc.com/files/Antenna assembly.pdf
http://www.goes-r.gov/hrit_emwin/ATR-2010-5482.pdf
Have you tried to get a usable signal out of your antenna yet?
No, I was not successful. I don't think the RTL-SRD is sensitive enough at that frequency. I have no LNA yet... What LNA did you get?
I got a custom inline deal that was built by a ham. it uses the atf10135 chip
http://www.mrs.bt.co.uk/dubus/9104-5.pdf
This is a document that mentions it.
Ebay has some commercial in-line amps for less than $100.
So far i haven't succeeded in acquiring signal yet either.
I think the dish is fine, feed on these wifi dishes is iffy and I think the RTL2832U most likely does a poor job at receiving these frequencies.
GOES-R team used a Ettus Research USRP as the receiver. I really ideally want this to work on RTL-SDR / RTL2832U but i dunno if this is dooable. We shall see I guess.
http://www.mrs.bt.co.uk/dubus/9104-5.pdf
This is a document that mentions it.
Ebay has some commercial in-line amps for less than $100.
So far i haven't succeeded in acquiring signal yet either.
I think the dish is fine, feed on these wifi dishes is iffy and I think the RTL2832U most likely does a poor job at receiving these frequencies.
GOES-R team used a Ettus Research USRP as the receiver. I really ideally want this to work on RTL-SDR / RTL2832U but i dunno if this is dooable. We shall see I guess.
This is the design I've got so far.(Yes I know I don't have any filtering circuitry, this is just a rough sketch). It still needs the adc, fpga, power supplies and usb micro controller(Probably a cypress chip)
thanks for sharing 
- unfortunately I am not able to report any solid success thus far. I think either my feedhorn, a connector or the dongle ain't cutting the mustard.
with the amp inline the noise floor is higher and when i move the antenna around i get a higher SNR sweeping across the waterfall but I have no way of telling if this is the GOES-13 signal.
When i move / wiggle the N-Female to MCX male pigtail at the MCX end I see the same stuff sweeping back and fourth on the waterfall.
- unfortunately I am not able to report any solid success thus far. I think either my feedhorn, a connector or the dongle ain't cutting the mustard. with the amp inline the noise floor is higher and when i move the antenna around i get a higher SNR sweeping across the waterfall but I have no way of telling if this is the GOES-13 signal.
When i move / wiggle the N-Female to MCX male pigtail at the MCX end I see the same stuff sweeping back and fourth on the waterfall.
Last night I tried the dish again. This time pointing it Inmarsat 4F3. This is what I got, the signals looks fairly strong, it gives me courage to keep trying for the goes 13 signals!
Nice! I've just confirmed that my dish, feed and amp are working! Only thing that should theoretically be stopping me from seeing the GOES-13/ GOES-14 1690 Mhz signal would be LOS issues or tuner sensitivity issues.
Amp and dish / dish feed is actually working down at 856 and 939 mhz when the dish and feed were designed for 2400mhz!!!
Amp and dish / dish feed is actually working down at 856 and 939 mhz when the dish and feed were designed for 2400mhz!!!
Spent the afternoon fiddling around. I know 100% my LNA is good. Dish should be good (1m grid parabolic) I can receive lower frequency stuff with the dish and amp. Thinking LOS issues or that the RTL dongles are deaf up at 1692mhz.
Unless the goes-13 and goes-14 signal is wide (just under 3mhz) and weak (even with an amp). - I can point toward the goes sats and see the noise floor increase. (I'm sampling at 3.2msps so should have about 3mhz bandwidth).
I was expecting to see some peaks on the FFT display - if there is a peak it is wide and flat - not sure if this is what I should be expecting.
Really starting to think the tuners are my issue (tried 2x R820t and 1x e4000)
Unless the goes-13 and goes-14 signal is wide (just under 3mhz) and weak (even with an amp). - I can point toward the goes sats and see the noise floor increase. (I'm sampling at 3.2msps so should have about 3mhz bandwidth).
I was expecting to see some peaks on the FFT display - if there is a peak it is wide and flat - not sure if this is what I should be expecting.
Really starting to think the tuners are my issue (tried 2x R820t and 1x e4000)
Yeah that's the conclusion I'm getting. There is the Hackrf, but I don't need the transmitting....
Found this, look's pretty promising. It's a lot cheaper than the ADRF2820. It has a built in LNA and VCO.
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=155639557&uq=635439602159738791
http://www.digikey.com/scripts/DkSearch/dksus.dll?Detail&itemSeq=155639557&uq=635439602159738791
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