cpp

Code based PPP (CPP)

When the strategy is set to CPP, navigation is based on pseudo range once again, but combined on two separate frequencies.

In order for this method to work, you need to present PR observations on more than L1.
This allows accurate Ionosphere delay compensation: we obtain similar results as to SPP without the need to model the ionosphere impact.

CPP versus PPP

• Similar Ionosphere bias cancellation
• No phase observation required: less signal observations required
• Troposphere is modeled and currently impossible to add to the Kalman filter, even when Filter is set to Kalman
• Reach advanced SPP results easier but still limited to metric solutions

Examples

(1) GPS metric positioning

Even though Ionosphere modeling is now turned off, we still obtain similar results to our best SPP examples:

cat conf.json

rinex-cli \
    -f test_resources/CRNX/V3/ESBC00DNK_R_20201770000_01D_30S_MO.crx.gz \
    -f test_resources/CLK/V3/GRG0MGXFIN_20201770000_01D_30S_CLK.CLK.gz \
    -f test_resources/NAV/V3/ESBC00DNK_R_20201770000_01D_MN.rnx.gz \
    -f test_resources/SP3/GRG0MGXFIN_20201770000_01D_15M_ORB.SP3.gz \
    -P GPS \
    -p -c rinex-cli/config/rtk/gpst_cpp_basic.json \
    | tee logs.txt

What's next

• Move on to PPP
• Learn how to resolve CGGTTS solutions for timing applications