Who is using frequency band around 3.043GHz ? - Page 1
Forum section: electronics / projects

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 06, 2015, 05:56:49 pm
content: Hi everybody, I hope there are some people on thins forum who can help me to resolve a mystery. I noticed, almost by accident, that periodically there is a lot of activity around 3.043 in area where I live - it is 26 floor (hight above ground) in downtown, Vancouver. It happens in periods and signal looks like a bunch of spikes from radar (weather radar?), but when I looked at databases and other sites likehttp://www.spectrumwiki.com/there is nothing that falls into the range from 3.001 to 3.099 GHz where I see the signals - centered around 3.043GHz. There are few things that I may expect to show up above 3.1GHz and right below 3.0 but no references to band from 3.0 to 3.1GHz. Who actually is using it? Is this a natural phenomena? radar? something else?I found this:NEXRADWeather Radar In the United States, NEXt-generation weather RADars (NEXRAD) operate in the band 2700-3000MHz.and this:SPY-1 Shipborne Air Surveillance Radar. Tuning range:3100-3500 MHzbut nothing in betweenSomeone told me that emergency services "see through the wall" scanners could be using it. Hmmmm, which models?

author: PA0PBZ
author_rank: Super Contributor
timestamp: May 06, 2015, 06:46:35 pm
content: Googling 3.043GHz shows some candidates like processors, T&M equipment and such.

author: ConKbot
author_rank: Super Contributor
timestamp: May 06, 2015, 06:53:23 pm
content: FCC freq allocation chart says marine navigation and radiolocation. I see a lot of licenses for the same too. And I also found a license to furuno, which lead me to thishttp://www.furunousa.com/ProductDocuments/FR2135S%20Brochure.pdf3.050 GHz +- 30 MHz, 30 / 60 kw.What kind of gear do you have? Could you put a spec-an in zero-span and get the pulse repetition and length?Might try Canada's equivalent of the FCC to see who's licensed around you.

author: LaserSteve
author_rank: Super Contributor
timestamp: May 06, 2015, 07:56:07 pm
content: OH! Canada...Your spectral chart is here:https://www.ic.gc.ca/eic/site/smt-gst.nsf/vwapj/CTFA2014EditionEN.pdf/$file/CTFA2014EditionEN.pdfSteve

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 06, 2015, 09:57:02 pm
content: Quote from: ConKbot on May 06, 2015, 06:53:23 pmYes Canadian FCC equivalent is called Industry of Canada or something like that. They have just generic 2 900 - 3 100 - "RADIOLOCATION" and "RADIONAVIGATION".The link to the radar info actually looks like a hit - thanks a lot! I was looking for something more specific like that. I can see a bay filled with boats and ships of all sizes from my window, but I never "heard" anything but few AIS signals.I was using small PCB log-periodic antenna, also small vivaldi antenna (2-11GHz or so) and R&S FSL6 Spectrum analyser. I was looking for WiMAX signals but entered 3.05 instead of 3.5GHz, I realized my mistake but then I just got curious. It looks almost impossible to zero-span on it I think because spikes are appearing plus minus 50MHz at random. This is why I guessed that it is a radar.

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 07, 2015, 05:18:37 am
content: Zero span workedI think the max hold trace has only 2 overlapping passes. First pass shows signal that is stronger. It showed up again for 2-3 min and then just disappeared.

author: LaserSteve
author_rank: Super Contributor
timestamp: May 07, 2015, 04:46:51 pm
content: Actually its assigned to "RadioNavigation(OR)" which is Aviation Radio Nav, Aviation Telemetry, or Radar.Steve

author: Alexei.Polkhanov
author_rank: Frequent Contributor
timestamp: May 10, 2015, 05:49:49 am
content: She is back. I think I know which boat it isThey just party there as far as I can see, spinning their radar cuz it has cool looking LEDs on it.

author: ConKbot
author_rank: Super Contributor
timestamp: May 15, 2015, 02:12:07 am
content: Interesting captures, if thats the rotation period you caught there, whatever radar that is, is spinning pretty quick!

author: Asim
author_rank: Regular Contributor
timestamp: May 15, 2015, 09:19:40 am
content: I am guessing you are having a lot of fun , I remember one time i was playing with a transmitter that uses 433 Mhz ( as i recall). Suddenly my brother opens my door shouting at me, asking me "what are you doing?" my car key is not working. I was laughing so hard yet excited that i was jamming the signal for him. ( the funny part for me was him assuming i was the problem)

author: numloxx
author_rank: Contributor
timestamp: May 15, 2015, 12:09:50 pm
content: Anything in that area is either Dept of Defence of ESSO Australia, who use 3.05Ghz.http://web.acma.gov.au/pls/radcom/assignment_range.range_lookuphttps://www.dropbox.com/s/osqtenin83440q2/2015-05-15%2020_08_17-Australian%20Communications%20and%20Media%20Authority_%20Register%20of%20Radiocommunication%20Li.png?dl=0

author: Monkeh
author_rank: Super Contributor
timestamp: May 15, 2015, 12:37:45 pm
content: Quote from: numloxx on May 15, 2015, 12:09:50 pmExcept he's not even near Australia.

author: dom0
author_rank: Super Contributor
timestamp: May 15, 2015, 01:07:40 pm
content: Quote from: Monkeh on May 15, 2015, 12:37:45 pmSame planet anyway.

author: numloxx
author_rank: Contributor
timestamp: May 15, 2015, 01:21:15 pm
content: Oh sorry, didn't realise.As you were

author: LaserSteve
author_rank: Super Contributor
timestamp: May 15, 2015, 03:06:52 pm
content: Keep in mind the Earth is divided into three regions for spectrum by international treaty:Each region gets a different spectrum assignment, and each nation somewhat tweeks the International Agreement to its own uses. It gets fun when you have small countries next to each other who have to share allocations.Some things such as Aviation, Marine Radio and Radar , Defense, and Amateur radio share some standards world wide.For example, by treaty, North of Line "A" which is within ~70 miles of the US-Canadian Border, I loose 420-432 Mhz from my Ham Radio Privileges. Canada uses that spectrum for business and local government land mobile radio. Drive from my home 20 miles, and I can use it. There is a buffer zone along the borderAnother example: In the US we have no Longwave broadcast radio, ie below 500 Khz.. Whereas Europe does.Here is an older map of the three International Telecommunications Regions. Each one has a massively different spectrum, allocation above 30 Mhz.http://www.itu.int/ITU-R/information/docs/emergency-regions.jpgIt looks like 2900 to 3100 is an older marine radar allocation.Steve