Gps Software Sirf
GlobalSat has released an update of their popular BU-353 USB GPS receiver. The new device looks and operates just like the.The only difference in appearance is the old model has 'GPS' on a white translucent strip on the top and the new one has G-STAR IV on a translucent black strip on the top.The model number is now BU-353 S4.The S4 in the model name is an indicator of the one significant change between the old and new models. The old model has a SirfStar III GPS chip in it. The new model has a SirfStar IV GPS chip in it.While that's the only obvious difference between the two - operationally they appear to be identical - it's a really big difference in performance.
I just got a new notebook computer a few days ago so I set it up on the kitchen table to test the new receiver. I downloaded and installed the driver from GlobalSat's web site because I don't have a DVD drive on the new computer. I also downloaded and installed GlobalSat's little GPSInfo test utility which is always handy for configuring and monitoring a new receiver (works with any generic NMEA device, not just GlobalSat's).Next I downloaded and installed Franson's GPSGate Express. I find it a handy tool to use whenever I have a new GPS receiver to test. I connected the S4 to the computer about the same time as I started downloading GPSGate. By the time GPSGate was installed and running, the brand new S4 already had a location fix.That's impressive because it was just sitting on the kitchen table beside the notebook.
A brand new GPS fresh out of the box needs to do a complete cold start to figure out where it is. This can usually take quite awhile and almost always needs to be done outdoors or it will take even longer or won't happen at all.I already had Streets & Trips installed. It had no problem finding and using the S4.I installed Street Atlas and it also found the S4 and started using it right away.I haven't had a chance to try it in a vehicle yet but if it works that well inside the house I have no concerns about its performance in a vehicle. I've attached a screenshot comparing the performance of the S3 and S4 versions of the BU-353. I didn't have a program that would allow two instances to run with a different receiver connected to each. So the S3 is running in nRoute and the S4 is running in GPSInfo.They both have similar satellite displays so you can see which satellites are being used and the signal strengths of them.This is with the notebook sitting on the kitchen table and the two receivers connected to opposite sides of the computer.As you can see, the S4 is doing much better than the S3.It should be pointed out that even the S3 version is doing very well for being indoors.ken.
Qualcomm Gnss
In the above test, the red represents the old BU-353 S3 unit, and the blue is the new BU-353 S4.The test was performed in downtown Toronto. The area was chosen because of its traditionally difficult environment for GPS navigation due to very tall buildings surrounding narrow streets.Both receivers were placed on the roof of the vehicle, approximately 30 cm (1 ft) apart, and the testing of both units was performed simultaneously.Notice that the blue line (the new S4) tracks the road more closely than the red line (the old S3). This difference can really be only observed in very difficult environments.The new BU-353 S4 had a fix on one or two more satellites during the test than the S3 version. Quote: Electrical Characteristics (Receiver)GPS Chipset: SiRF STAR IV GSD4eFrequency: L1, 1575.42 MHZC/A Code: 1.023 MHz chip rateChannels: 48Sensitivity: -163dBmAccuracyPosition Horizontal: position, velocity, altitude, status and controlNMEA 0183 MEA0183 V3.0 protocol, and supportsGPS Output Data: command GGA, GSA, GSV, RMC, VTG, GLL v2.2 (VTG and GLL are optional)GPS transfer rate: Software command setting (Default: 4800,n,8,1 for NMEA )Dynamic ConditionAcceleration: Limit Less than 4gAltitude Limit: 18,000 meters (60,000 feet) max.Velocity Limit: 515 meters/sec. (1,000 knots) max.Jerk Limit: 20 m/sec.3TemperatureOperating: -40° 80°CStorage: -40° 85°CHumidity: Up to 95% non-condensingPowerVoltage: 5V ±5%Current: 60mA typicalPhysical CharacteristicsDimension: 2.32' x 1.65' x 0.82' (59mm x 47mm x 21mm)USB Cable Length: 60' (152 cm)Low Noise AmpAmplifier Gain w/out cable: 27 dB TypicalFiltering: -25dB (+100 MHz)Output VSWR: 2.0 Max.Voltage: DC 3 5.0VCurrent: 15mA max @ 5VDCSeveral users of the new S4 version of this unit have commented on the faster start up time. This may be due to the following new implementation. First SiRFstar III based GPS receivers started to ship in 2005 (the GlobalSat 353 was one of the very first ones), so my guess is that the SiRF4 chip itself is unlikely more expensive now than the SiRF3 was years ago.
If anything, it is likely less expensive (again, only a guess). So we are just seeing discounted price of the old stock, and a higher price of a brand new product. Those who cannot wait for the latest and greatest will pay a price premium.
Those who are patient to wait a few months for the price to drop will save a bit.EDIT I just found some historical info from December of 2007. At that time the old S3 version sold for Regular price: $79.99 Sale price: $45.99. I note that you got the GPSinfo program working. Even though the GPS is registering in Streets and Trips, GPSinfo does not detect the BU-353S4 when I try to conduct a scan. Any idea what I am doing wrong?Mine just worked.
I didn't even have to tell it to scan. It already had the correct settings selected so I just had to poke the 'Start GPS' button and the sentences started to scroll.Oh. Memory is starting to trickle back.
I first tried to download GPSInfo from their website when I downloaded the drivers (no DVD drive on the notebook). But the file seemed to be broken. The drivers worked fine but the GPSInfo download was really short and when I tried to open it it tossed an error that it was an invalid file. I tried downloading it three times with the same results.So I broke down and dug out my portable DVD drive and installed GPSInfo from the mini CD that came with the device. Installation was clean and it ran first try as described above.ken. I've attached a screenshot comparing the performance of the S3 and S4 versions of the BU-353. I didn't have a program that would allow two instances to run with a different receiver connected to each.
Csrg0530
So the S3 is running in nRoute and the S4 is running in GPSInfo.They both have similar satellite displays so you can see which satellites are being used and the signal strengths of them.This is with the notebook sitting on the kitchen table and the two receivers connected to opposite sides of the computer.As you can see, the S4 is doing much better than the S3.It should be pointed out that even the S3 version is doing very well for being indoors.ken.Hi. Am I seeing those images correctly? Does the S4 put you in the middle of the northern Pacific? My S4 arrived today so I put it to the test against a BU-353 (S3) on a computer running Win 7 64.
A couple of things I noted;1)You don't need the CD as the appropriate drivers will be downloaded from Windows.2)The copy of GPS Info on my CD is old and won't work with Win 7 64. It can't find any COM ports at all.I downloaded the version at GlobalSat support and it worked great.The S4 was considerably better than the S3 in the location I tested. I also tried the Cold Start button in GPS Info with the S4 and had lock in 45 seconds at this location. For easy comparison, I just opened 2 instances of GPS Info and pointed each at the appropriate COM port (7 and 9 in my setup).I wiill test it against a MTK I bluetooth GPS later and expect it will at least equal the performance of that chip.Terry.