srx-10 Performance

OPEN-SKY, STATIC, GPS STANDALONE PERFORMANCE

The figure below shows the srx-10 accuracy in the following conditions:

  • Open sky, static

  • GPS only

  • Front-end bandwidth: 18 MHz

  • Front-end sampling frequency: 32.736 Msps

  • Host computer computation power equivalent to 20% of standard Dual-Core Pentium

  • Unaugmented (no SBAS corrections applied)

 

srx-10: Open sky, static, GPS standalone performance

SBAS AUGMENTATION

The srx-10 can track SBAS GEO satellites and process GPS wide area corrections to improve the positioning accuracy down to the meter level. The following figures show the accuracy improvement obtained processing with srx-10 the EGNOS corrections freely available over Europe. The standard GPS standalone positioning errors are also shown for comparison below.

srx-10 positioning errors using EGNOS corrections
srx-10 positioning errors using GPS only

GPS L1 SINGLE-FREQUENCY RTK

The following figure shows the positioning errors of the srx-10, used as a rover performing L1 single-frequency RTK with integer ambiguity resolution. It can be observed that the positioning errors are in the order of millimeters.

srx-10 positioning errors performing L1 single-frequency RTK

PERFORMANCE IN DEEP URBAN SCENARIO

srx-10 has been validated through exhaustive experimental campaigns in most-demanding urban scenarios, in order to test the receiver capabilities in terms of navigation continuity and resistance against the main expected threads, namely: poor visibility and strong multipath (LoS and, mainly, NLoS).

In these scenarios, the srx-10 can work in assisted mode using the A-GNSS data stream generated by GMV's magicGNSSservice. GPS clock and ephemeris prediction intervals spanning from 1 to 7 days have been tested.

The figures below show the percentile curve of the estimated horizontal positioning error and some examples of horizontal trajectories obtained during an thorough experimental test campaign with srx-10 and a commercial mass-market GPS-L1 HW receiver, in the following conditions:

  • Deep urban environment (Madrid downtown)

  • Host computer computation power around 200 MIPS, roughly equivalent to:
    • 40% of PXA-270 (low-cost embedded processor, even without Floating Point Unit)
    • 3% of standard Dual-Core Pentium

  • Front-end bandwidth: 2.5 MHz

  • Front-end sampling frequency: 4.092 Msps

  • Low-cost patch antenna

  • PVT based on Kalman filtering

  • srx-10 working in assisted mode

 

srx-10: Urban Environment
srx-10: Urban Environment
srx-10: Comparison