Loading... Please wait...

Blog

NS-HP-GL Performance

Posted by

Short Baseline 15 Hour Testing 

Accuracy: CEP 50% 0.33cm, R95 0.69cm, SEP 50% 0.63cm

.

Short Baseline Recycle Power Time to RTK Fix Testing, 75 Trials

Average time to RTK Fix 22.5 sec

.

Longer Baseline Time to RTK Fix Testing, 5 Trials Each

.

11 Km Baseline Drive Test (Blue: RTK Fix, Green: RTK Float)

Using HX-CSX601A Antenna

Using TW2710 Antenna

At this farther than 10Km baseline testing, survey grade HX-CSX601A antenna, generating higher quality measurement signal, performs better than the TW2710 antenna resulting in all RTK Fix solutions.

.

National Chiao Tung University Running Track Walking 7 Laps Short Baseline Test

On outer tracks, although at some places there are trees and building nearby blocking partial sky, the result tracks run in parallel without any jumps. 

Number of Satellites in Use for the 7 Laps

HDOP for the 7 Laps

Some single-frequency RTK receivers list 10sec RTK initialization time without specifying under what special condition it's being tested, which generally is not true for other usage cases. NS-HP-GL too can also demonstrate near 10sec RTK initialization time for constrained moving base application. NS-HP-GL is S2525F8-GL-RTK module in breakout board form; below video is S2525F8-GL-RTK module in evaluation board form showing an average of 11sec RTK initialization time. 

Compared with RTK receivers running RTKLIB, NS-HP-GL has simpler setup and better optimization for commercial realtime RTK applications. For those interested in post-processing using RTKLIB, NS-HP-GL's raw measurement output is also RTKLIB compatible with version 2.4.3 b28

Comparing single-frequency NS-HP-GL with more expensive dual-frequency GPS/GLONASS RTK receivers, the latter has faster RTK initialization time (< 10 sec @ < 10Km baseline) and could work over 50Km baseline. NS-H-GL works under 10Km baseline and has 10sec ~ couple minutes RTK initialization time depending on baseline length.

Nearly all dual-frequency GPS/GLONASS RTK recivers use GPS L1 C/A + GPS L2 P + GLONAS L1/L2 C/A codes; totaling 11 ~ 17 usable dual frequency satellites above 15 degree elevation angle. There is a new "Multi-Band, Multi-Constellation Centimeter-Accurate GNSS" that claims to support GPS L1/L2 and is hardware-ready for GLONASS G1/G2, BeiDou B1/B2, Galileo E1/E5b, QZSS L1/L2 and SBAS. "hardware-ready" in plain English means no such capability yet. Its GPS L2 capability is not the typical L2 P but the new L2C which is not fully operational yet. The untold truth is this "Multi-Constellation Centimeter-Accurate GNSS" currently only has 3 ~ 7 dual frequency satellites of single GPS constellation overhead to work with, far less in number than existing dual-frequency RTK receivers on the market that has 11 ~ 17 dual-frequency GPS and GLONASS satellites to use. 

.

GPS L1/L2C Capable Satellites

.

GPS L1/L2P Capable Satellites

.

GPS L1/L2P + GLONASS L1/L2 Capable Satellites

.

View Comments


What's Moving Base RTK For?

GPS receiver output correct course over ground (COG) information when in motion. It represent movement direction. Without movement, the output COG information may be incorrect.Some applications, such as marine vessel autopilot, require knowledge of accurate heading direction regardless of movement direction.  Two NS-HP or NS-HP-GL configured in moving base RTK mode gives precise heading in the direction [...]

Read More »


NAVIC (IRNSS) Signal Reception

We are excited to show live signal cold starting of a new under-development GNSS receiver capable of receiving India's NAVIC signal (formerly called IRNSS) and GPS signal.

Read More »


NS-HP or NS-HP-GL ?

NS-HP or NS-HP-GL are single frequency RTK receivers. For reliable consistent RTK operation, they require 12 or more usable satellite signals above 15 degree elevation angle with SNR no less than 38dB/Hz. With 10 or 11 usable satellite signals, we've seen less than 0.1% rate of getting incorrect RTK Fix off by centimeters ~ decimeters (no [...]

Read More »