hello eric i was searching for your mode s ads b code in gnu radio so pleas can you send it to me .
cheers doha Eric Cottrell wrote: > > Hello, > > I was emailed by a few people off list that are interested in the > Mode-S/ADS-B code. I am still working on it. > > I got the DPD Productions antenna just before Thanksgiving, but it was too > windy to put up right away. Sitting on the first floor in the middle of a > wood frame house, the antenna was picking up aircraft from 40 to 140 miles > away depending on direction. I could not see low altitude aircraft to the > south of the nearest busy airport, which is eight miles south. 44 feet > above the ground on my roof is a different story and I can see aircraft > from 150 to 210 miles depending on direction. Although the DPD antenna is > higher gain, I do not get the same level of interference as the colinear. > The DPD antenna is suppose to be a narrow bandwidth antenna. I tried the > wideband preamp with the DPD antenna and had the same problem with the > noise floor rising and decreasing range. > > I bought a SBS-1 last week. It is a commercial Mode-S/ADS-B receiver that > is smaller than the USRP. The sensitivity seems slightly better. It > could handle the wideband preamp better with just a slight decrease in > range. I am currently working on providing a port 30003 compatible output > for my receiver. Then I can use Planeplotter and can compare my code to > the SBS-1. > > My nearby major airport has a ASDE-X system for monitoring aircraft and > vehicles on the airport surface. It appears they are installing an ADS-B > Multilateration system as I get a couple of the sensors. They use DF18 > (Non-Transponder Extended Squitter) and just send an ID and > Multilateration status. Two of them ID as STEST123 with the category of > Fixed Ground/Tethered Obstacle. The third recently appeared with an ID of > PTEST123. The SBS-1 also picked up the IDs so it can decode at least some > DF18 formats. > > I want to do a UAT receiver and was planning a trip to Philly to look at > the TIS-B/FIS-B ground segment transmissions. I got a surprise when I > found out the New England area has TIS-B/FIS-B services. Someone did a > demo of a receive only system. The TIS-B service only transmits if there > is a ADS-B aircraft using UAT in the area. Being able to receive TIS-B > would be good because it includes non-ADS-B aircraft. There is also > cross-linking of UAT and Mode-S so ADS-B aircraft on Mode S ADS-B should > show up on UAT. > http://www.youtube.com/watch?v=NmYrUGxRC88 > > It is an iPhone application using a separate UAT receiver costing $1100. > http://www.skyscope.net/ > > I looked at the 978 MHz UAT frequency and think I see the signal but it > does not completely match up with the specifications. The system uses > slightly over 1 megabit per second FSK with a over 600K shift. I see what > looks like the mark frequency, but instead of the space frequency I get > another signal at the center frequency (978.0 MHz). If I use a simple PLL > FM detector flow graph with a scope sink I do see what looks like a > bitstream. The current plan is to get my laptop updated and setup, then > go mobile. I suspect there is a transmitter at a nearby airport. > > 73 Eric > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- View this message in context: http://old.nabble.com/Mode-S-ADS-B-and-UAT-tp30383884p31419411.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
