tag:blogger.com,1999:blog-5679825113811261335.post3666758869133431049..comments2023-09-19T23:57:37.836-07:00Comments on Michele's GNSS blog: Is SiRF really bringing back carrier phase?Michelehttp://www.blogger.com/profile/03657889163945060210noreply@blogger.comBlogger20125tag:blogger.com,1999:blog-5679825113811261335.post-91875910160275692892014-03-06T22:59:25.168-08:002014-03-06T22:59:25.168-08:00Hi Michele
look at this link... I have do post p...Hi Michele <br /><br />look at this link... I have do post processing with Leica Geo Office, it can increase accuracy by sub meter. I think enough for GIS not realtime<br /><br />http://www.leica-geosystems.com/en/Product-News_934.htm?id=4933adhityohttps://www.blogger.com/profile/01742186200517482977noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-86110602128468404672014-03-04T01:34:01.918-08:002014-03-04T01:34:01.918-08:00Hello Adhityo,
Interesting, could you please prov...Hello Adhityo,<br /><br />Interesting, could you please provide references backing up your statement?<br /><br />In my tests, carrier phase out of a standard SS4 was not good. Of course pseudoranges, although heavily smoothed, might still be useful for DGPS.<br /><br />Michele<br />Michelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-55546692256353285142014-03-04T01:21:23.987-08:002014-03-04T01:21:23.987-08:00Hi Michele Bavaro,
Sirfstar IV definitely can bein...Hi Michele Bavaro,<br />Sirfstar IV definitely can being post processing. Leica-Geosystems GS05 use SIRF chipset and new update software can log raw data to incrase accuracy adhityohttps://www.blogger.com/profile/01742186200517482977noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-61779790956105103652012-08-18T01:36:00.238-07:002012-08-18T01:36:00.238-07:00Hello Jens,
In my experience, the GPS chipsets in...Hello Jens,<br /><br />In my experience, the GPS chipsets in smartphones are shipped with a bespoke FW which is usually quite limited compared to OEM units. It may or not be the case with your Samsung.<br />Anyway -if you manage to have a reliable serial connection to the chip - enabling raw data is as easy as sending a binary message (MID128, "Initialise Data Shource") to it where BIT4 ("Enable Nav Lib Data") is set.<br />Please mind that nav lib data are usually a lot of data, so 4800 and 9600 bps are not likely to be enough to sustain all the data coming through.<br /><br /><br />I have not managed to use successfully SiRF carrier phase yet, but I have a lot of scattered C code to parse raw observations.<br />A common pitfall is in the representation of double precision floating point values which changes in different versions of the baseband.<br /><br />It'd be very untidy to post it here so please contact me on OneTalent email for that.<br /><br />Cheers,<br />Michele<br />Michelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-42396211211384817272012-08-17T23:57:23.053-07:002012-08-17T23:57:23.053-07:00Hi,
i am a student of the ruhr university in Boch...Hi,<br /><br />i am a student of the ruhr university in Bochum, Germany, and currently I am working on my master thesis. I am trying to get the raw GPS data from the SiRFstar IV in the Samsung Galaxy S2 smartphone, but I am still at the beginning. Can you perhaps help me? I am looking for some code (in best case C) how to get the data from the chip. My aim is to modify the c-code on the sgs2 to get this data from the chip and try to implement some anti gps spoofing techniques on the smartphone. If you can help me with that, here is my email adress: jens.jakobi (at) ruhr-uni-bochum.de<br /><br />cheers<br />JensJenshttps://www.blogger.com/profile/00444784205207671667noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-45560278827260832852012-03-04T15:40:15.083-08:002012-03-04T15:40:15.083-08:00Hi Michele Bavaro,
Thank you for answer my questi...Hi Michele Bavaro,<br /><br />Thank you for answer my questions.<br /><br />I put, on the same link, some pictures of yours data signals, C1,L1,D1,S1,<br />they look very good, very cleam, no cycle slip. With antenna model have you worked with ? It looks great for me !<br /><br />cheers !<br /><br />julio menezesyjmenezeshttps://www.blogger.com/profile/17267438109139967140noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-34581336126768708072012-03-04T06:32:27.762-08:002012-03-04T06:32:27.762-08:00Dear Julio,
Thank you very much for spotting the ...Dear Julio,<br /><br />Thank you very much for spotting the error, it is now fixed!<br /><br />Yes data are collected using a splitter.<br /><br />I think that -in theory- it should be possible to flash your S1315F with a RAW data firmware file... as long as you can get hold of it!<br /><br />Cheers,<br />MicheleMichelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-26189389857475558382012-03-04T06:20:42.711-08:002012-03-04T06:20:42.711-08:00Dear Michele Bavaro,
Nice to see onetalent-gnss. ...Dear Michele Bavaro,<br /><br />Nice to see onetalent-gnss. <br /><br />I am interested in FOSS-GPS and I took your data <br /><br />120218_lowcostrtkperformance.7z<br /><br />Looking in Rinex Header I realize a minor mistake on XYZ APPROX POSITION.<br />I fixed it and processed under GNU/LINUX with:<br />a) RTKLIB rtkpos<br />b) GPSTK DDBase<br /><br />I supose you have collected static data with an antenna splitter as both receivers produced the same final position.<br />Am I right ? If not, please give me more details, I am trying to learn how to use both softwares.<br /><br />best regards,<br /><br />julio menezes<br /><br />I put my results here, if you would like to see:<br />http://gpl2.com.br/mb_test<br /><br />Please, If it is not an abuse<br />I bought an Venus634FLPx, here in my country I could not find S1315F or U-bloxLEA T ( time serie ).<br />Do you think if It would be possible to replace the firmware to get raw carrier phase from this FLPx ? ( let say replacing with SkyTraq: Venus S1315F firmware, as both are Venus)? <br /><br />thx again !yjmenezeshttps://www.blogger.com/profile/17267438109139967140noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-2405003142349180052011-11-29T06:19:45.019-08:002011-11-29T06:19:45.019-08:00I don't have Sirf software but if you give me ...I don't have Sirf software but if you give me a RINEX file, I can sure have a look! I have a few matlab routine that could be interesting to run. One of the thing I was thinking was to collect data with your Dual GSD4e, with antenna spaced by a meter (measured precisely) and aligned to the north (in order to have a known baseline). If you have data of a close reference station, it would also be interesting to see if RTKlib can perform reliable RTK with a reasonable time to fix.. I'll be glad to have a look!<br />Best regards!<br />SébastienSebastienhttps://www.blogger.com/profile/01311668189452551607noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-58359938098426730592011-11-29T02:47:45.874-08:002011-11-29T02:47:45.874-08:00Hi Sebastien,
I didn't yet. I am waiting to h...Hi Sebastien,<br /><br />I didn't yet. I am waiting to have GPS+Glonass measurements now.<br />Would you have time to process the data if I collect them for you?<br /><br />Bests,<br />MicheleMichelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-33568809635868865382011-11-29T02:35:24.298-08:002011-11-29T02:35:24.298-08:00Hello Michele,
Did you have time to have a look at...Hello Michele,<br />Did you have time to have a look at the quality of the Sirf carrier phase measurements?Sebastienhttps://www.blogger.com/profile/01311668189452551607noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-88055839931893889512011-09-22T08:07:42.141-07:002011-09-22T08:07:42.141-07:00Guys,
I suppose you know, but if not that's g...Guys,<br /><br />I suppose you know, but if not that's great small program to obtain RINEX data from receivers with SirfSTAR chipset.<br /><br />http://rapidshare.com/files/459582957/kinematic-release-0.11.rar<br /><br />I tested it with Navibe GB732 and works. I don't know if is possible to connect that receiver to RTKlib. <br /><br />Best regards,<br />LukaszLukaszhttps://www.blogger.com/profile/16723125598056595227noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-17174279629222867282011-09-11T01:41:04.852-07:002011-09-11T01:41:04.852-07:00Hi Svenn,
I am afraid I don't know at the mom...Hi Svenn,<br /><br />I am afraid I don't know at the moment if the MaestroWireless and the Wi2Wi module support raw data. I think you'd better stick to uBlox if your intention is to use RTKLIB. uBlox itself has an online shop where you can buy LEA-4/5/6T, or your could try Chinese wholesale:<br />http://www.dhgate.com/ublox-lea-4t/p-ff80808129d93e870129ee82838a43d2.html<br /><br />Cheers,<br />MicheleMichelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-69594921213297409802011-09-10T14:30:30.340-07:002011-09-10T14:30:30.340-07:00I want to shop some parts for DIY RTK and found th...I want to shop some parts for DIY RTK and found this blog helpful, but before I take the risk of ordering modules I cannot use, I allow myself to ask if the modules Maestro A2100-A or Wi2Wi W2SG0084i, which both use sirf IV, can provide the necessary data output needed for further experiments with RTK. I can't find any support for Sirf IV on RTKLIB, but I can also not find Ublox 4/5/6-T on Mouser, where I am going to place my order. I want to pair the GPS for the rover with a Beagleboard, also from Mouser.Svennhttps://www.blogger.com/profile/09587784598151862536noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-52977271340975228802011-09-06T02:29:19.158-07:002011-09-06T02:29:19.158-07:00This is a great opportunity for cheap RTK at last....This is a great opportunity for cheap RTK at last.<br />What would be interesting to check:<br />- Is the carrier phase of good quality i.e. is the half ambiguity resolved? One way to check it is a zero-baseline test with a good receiver (that as its half ambiguities resolved), plotting double difference and checking if residuals are centered on integer values.<br />-Zero baseline test using code and doppler measurements, to have an idea of the level of noise and multipath on the different tracking loop. If it is too high, RTK might be difficult.<br />-Is CN0 also recorded and output by the receiver? It can be useful for weighting measurements in the processing.<br />Cheers,<br />SébastienSebastienhttps://www.blogger.com/profile/01311668189452551607noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-7254037816791609172011-09-01T07:15:51.271-07:002011-09-01T07:15:51.271-07:00Hi Mirko,
Beautiful. Unk4002 is MID64.2 (0x40=64 ...Hi Mirko,<br /><br />Beautiful. Unk4002 is MID64.2 (0x40=64 0x02=2)!<br />So, ORG4472 outputs everything we need and it's cheap :D<br /><br />I don't think we need MID7 <i>for the clock bias</i> as that can be calculated by the PVT and SiRF guarantees that it's not too big so that PVT starts in a good convergence region (sats are evaluated close to their real position).<br />MID7 is useful for the week number though. <br /><br />MID30 is not important as the sat. positions are calculated inside the PVT too. MID41 is not raw data AFAIK. MID8 and/or MID15 are useful if we want to generate Rinex NAV too.<br /><br />Summarising:<br />(I think) MID28, MID7, MID8 is all we need for standalone, differential, and RTK position calculation. <br /><br />I have SiRFLive from a previous project, but it can be found on dodgy chinese websites..<br /><br />If you post the raw data somewhere we can definitely give them a go: I already have a simple parser that generates Rinex3.0 OBS from the SiRFdemo (or SiRFlive) log.<br /><br />Cheers!<br />MicheleMichelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-79481678064235788982011-09-01T07:00:09.283-07:002011-09-01T07:00:09.283-07:00Hi Michele,
Inventek should launch soon a new ver...Hi Michele,<br /><br />Inventek should launch soon a new version of ISM480 with external antenna. This comes from ISM480:<br /><br />28,0,145953764,7,1.4867360054310077e+005,2.0472250788286384e+007,1.8310977e+004,2.0472265440004222e+007,8440,191,40,40,40,40,40,40,40,40,40,40,200,100,0,0,0 <br />28,1,145953764,19,1.4867360054310077e+005,2.0705526380466010e+007,1.8679297e+004,2.0705529234693255e+007,8440,191,42,42,42,42,42,42,42,42,42,42,200,100,-1,0,0 <br />28,2,145953764,8,1.4867360054310077e+005,2.1572945108205695e+007,1.7925490e+004,2.1572951958368298e+007,8440,191,41,41,41,41,41,41,41,41,41,41,200,100,-1,0,0 <br /><br />Instead, this comes from ORG4472:<br /><br /><br />28,6,648932673,2,3.06293000301797e+005,2.4040936854e+007,1.8650136719e+004,2.4040939899e+007,30000,255,33,33,33,33,33,33,33,33,33,33,1000,500,-4,1,0<br />28,7,648932673,5,3.06293000301797e+005,2.4562170887e+007,1.7849621094e+004,2.4562176215e+007,30000,253,29,29,29,29,29,29,29,29,29,29,13,500,0,11,0<br />Unk: 40021D14020026AE1C82570E409BAF9D6A030BFAF78C0002000D00E9AED6000000300000A6B1000019000117058A00C7000002C0004500E9ADE0000200000000000001<br />Unk: 40021E14020026AE11845708C185425F756C0C0D03730002000D00E9AED60000001100002FCE00001900FFFE002F00C1000002AE004800E9ADE0000100000000000001<br />Unk: 40021914020026AE0E70570737A5AA306FF50C1536030001000B00E9AED600000011000034CF00001900005C06BD00B2000001C6003600E9ADE0000000000000000001<br />Unk: 40021F14020026ADFF8C56FFC593A134762B0BD361F80005000900E9AED60000002C00009EEE00001900FFBA04DE00C0000002AC004700E9ADE0000100000000000001<br />Unk: 40021514020026ADEDAD56F6D61C56D647440B8B46840005000400E9AED60000005D00015B700000190000D400C900A800000232005E00E9ADE0000100000000000001<br />Unk: 40020C14020026AE1664570B31DB8D3B1DCE0C3FE98AFFFF000300E9AED6000000020000080000001900FE98F92100660000018A004D00E9ADE0000000000000000001<br />Unk: 40020214020026AE25FA5712FCD47CCCCB0D0C437D440000000100E9AED60000001000000EDA0000190000D1062E00B500000209003F00E9ADE0000200000000000001<br />Unk: 40020514020026AE1544570AA1CA9B085D820BBCB9BFFFF5001300E9AED50000001C000066000000190001B211AB0081000002D3006500E9ADE0000100000000000001<br />30,29,3.06293000000e+005,1.5785849135e+007,4.3501820427e+006,2.0972327451e+007,-1.7224569988e+003,2.0124431913e+003,8.8621226066e+002,2.3582913136e-004,3.7699630744e-012,1,0.0000000000e+000,0.0000000000e+000,1.5271326303e+000<br />30,30,3.06293000000e+005,1.7839796923e+007,1.1121673794e+007,1.5879575868e+007,7.1931816948e+002,1.9687881175e+003,-2.1360135443e+003,9.0749511809e-005,-5.9895404608e-012,1,0.0000000000e+000,0.0000000000e+000,1.5699721575e+000<br /><br /><br />As you can see, I have some Unk strings in the middle; however the other messages looks fine. Do you have a justification of that? I am using Sirfdemo; I would like to try with Sirflife. I have a long (1 hour - 12 MByte) .gps file. Do you want try to process those data? I can post the file somewhere. <br /><br />MID64.2 looks interesting. It could help to built the covariance matrix... I will try to also capture this message.<br /><br />I saw that MID 7 is also important, because it has the clock bias. <br />So we will need:<br />MID 7<br />MID 28<br />MID 30<br />Maybe MID 41<br />Maybe 64.2<br /><br />Any other?<br /><br />Cheers<br /><br />MirkoMirkohttps://www.blogger.com/profile/00646072378561792800noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-84025199208628317932011-08-30T05:41:45.455-07:002011-08-30T05:41:45.455-07:00Hi Mirko,
Yes we will always need to re-start the...Hi Mirko,<br /><br />Yes we will always need to re-start the chip with Nav Data Lib enabled (as it used to be with older SiRF III). <br /><br />The only thing I don't like of the Inventek ISM480 is the passive patch antenna built-in, which is no good for RTK. If it would be possible to have the same on the ISM420 though..<br /><br />Mirko have you seen the MID64.2? Those pseudorange, Doppler, and carrier phase accuracy "estimators" are very interesting for developing a custom PVT, don't you agree?<br /><br />Cheers.<br />MicheleMichelehttps://www.blogger.com/profile/03657889163945060210noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-68470252253446159092011-08-30T05:31:31.647-07:002011-08-30T05:31:31.647-07:00Hi again,
I am having some discussion with the te...Hi again,<br /><br />I am having some discussion with the technical support people of Inventek. ISM480F1 looks to be a raw data enabled 5Hz SIRF IV module... wow! Firmware GSD4e_4.1.0-P1 12/20/2010. It could be the choice... coming soon with updated info.<br /><br />Cheers<br /><br />MirkoMirkohttps://www.blogger.com/profile/00646072378561792800noreply@blogger.comtag:blogger.com,1999:blog-5679825113811261335.post-48953511154204069322011-08-29T04:19:07.718-07:002011-08-29T04:19:07.718-07:00Hi Michele,
thanks for this post. I think we coul...Hi Michele,<br /><br />thanks for this post. I think we could also try to write a list of all gps modules that provide raw data measurements and cost less than 250$. Another important requirement is to be "in production". Most of popular raw data chipset are discontinued (Sirf II, AC-12, Garmin OEMs, etc.) and then not suitable for new designs. Do you know any (low cost) raw data receiver compatible with Galileo?<br /><br />Cheers<br /><br />Ps: remember for everyone is willing to try Sirf raw data output (MID 28) that it is NOT enabled by default! Use MID 128 to enable MID 28.Mirkohttps://www.blogger.com/profile/00646072378561792800noreply@blogger.com