GPS World, January 2011

Vehicle Navigation RECEIVER DESIGN FIGURE 7 Percentage of solutions computed exhibiting redundancy redundant solutions are computed are considered here since nonredundant solutions lead to residuals with values of zero As discussed above the analysis of these residuals gives an estimate of the quality of the measurements generated FIGURE 8 shows the histograms of the residuals from all GPS GLONASS processing strategies Once again it is important to emphasize that only residuals from solutions with redundancy are considered In addition the results presented are limited to those epochs during which the vehicle was in the downtown portion of the test For the purposes of this presentation an upper GDOP threshold of 10 was set It is interesting to note that in all cases assisted HS standard wide correlator and commercial surveygrade processing the relative RMS values of the GPS and GLONASS residuals are about the same These results indicate that irrespective of the signal processing strategy employed the GLONASS measurements are of a similar quality to the GPS measurements The number of residuals available is however different between the standard and HS solutions as the latter produce more measurements and more redundant solutions hence more residuals The processing strategy obviously had a signifi cant impact on the availability of redundant solutions as discussed in the previous section a b c FIGURE 8 GPS GLONASS range residuals comparison a Assisted HS GPS GLONASS b Standard wide correlator c Surveygrade receiver RMS values and the percentage of solutions used in the histogram are also shown FIGURE 9 shows the histograms of the range residuals from GPSonly processing In this case the navigation solution is a GPS only navigation solution though in the case of the assisted HS receiver the measurements used are identical to those used in Figure 8 Clearly the assisted HS receiver has a greater availability of redundant solutions compared to the standalone receiver which is to be expected Also the assisted HS GPS receiver residuals have a slighter lower RMS than when a GPS GLONASS Dynamic Capture Ricoh G700SE Geo Data New Imaging Solution Camera Features Extremely rugged Waterproof dustproof 12 MP Resolution with 5 x Zoom High Definition 720p video Wireless ready Bluetooth WIFI Read barcodes directly thru lens Populate data while in the field Capture up to 20 memo fields Embed data in image header Store sound in image header Streamlines workflow Password security WORM SD card compatible Connects to Laser Range Finders GPS data ready Optional GPS mounts on camera Store GPS data directly in image Print GPS data directly on image Customizable firmware Recognized Industries Automotive Disaster Recovery Education Event Marketing Government Healthcare Housing Insurance Law Enforcement Military Manufacturing Police Fire Real Estate Security Utilities And much more Dynamic Storage Cloud Imaging Management Index Store Manage Search Retrieve User Friendly Interface Versatile Scalable Disaster Protection Remote Collaboration Secure File Access 24 x 7 Contact us for your 90 Day Trial of Dynamic Storage dynamic capture@ ricoh usa com www RicohDC com 19098909039 www gpsworld com January 2011 GPS World 55