gnss-rtk 0.8.0

GNSS position solver
Documentation 
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use crate::prelude::{Candidate, Carrier, Epoch, Observation, SV};

#[test]
fn best_snr_pseudorange() {
    {
        let (observations, prefered) = (
            vec![
                Observation {
                    snr_dbhz: Some(20.0),
                    phase_range_m: None,
                    pseudo_range_m: Some(1.0),
                    ambiguity: None,
                    doppler: None,
                    carrier: Carrier::L1,
                },
                Observation {
                    snr_dbhz: Some(30.0),
                    phase_range_m: None,
                    pseudo_range_m: Some(2.0),
                    ambiguity: None,
                    doppler: None,
                    carrier: Carrier::L2,
                },
            ],
            Observation {
                snr_dbhz: Some(30.0),
                phase_range_m: None,
                pseudo_range_m: Some(2.0),
                ambiguity: None,
                doppler: None,
                carrier: Carrier::L2,
            },
        );
        let cd = Candidate::new(SV::default(), Epoch::default(), observations);
        assert_eq!(cd.best_snr_observation(), Some(prefered));
    }
}

#[test]
fn l1_l2_narrowlane() {
    let codes = vec![
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            ambiguity: None,
            pseudo_range_m: Some(64.0),
            carrier: Carrier::L1,
        },
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            ambiguity: None,
            pseudo_range_m: Some(128.0),
            carrier: Carrier::L2,
        },
    ];
    let cd = Candidate::new(SV::default(), Epoch::default(), codes);
    let cn = cd.code_nl_combination();
    assert!(cn.is_some(), "failed to form Cn_narrow combination");
    let cn = cn.unwrap();
    assert_eq!(cn.rhs, Carrier::L1);
    assert_eq!(
        cn.value,
        (Carrier::L1.frequency_hz() * 64.0 + Carrier::L2.frequency_hz() * 128.0)
            / (Carrier::L1.frequency_hz() + Carrier::L2.frequency_hz())
    );

    let codes = vec![Observation {
        snr_dbhz: None,
        phase_range_m: None,
        doppler: None,
        ambiguity: None,
        pseudo_range_m: Some(64.0),
        carrier: Carrier::L1,
    }];
    let cd = Candidate::new(SV::default(), Epoch::default(), codes);

    assert!(
        cd.code_nl_combination().is_none(),
        "Cn_narrow should not be feasible!"
    );
}

#[test]
fn l1_l5_narrowlane() {
    let obs = vec![
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            pseudo_range_m: Some(64.0),
            ambiguity: None,
            carrier: Carrier::L1,
        },
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            pseudo_range_m: Some(128.0),
            ambiguity: None,
            carrier: Carrier::L5,
        },
    ];
    let cd = Candidate::new(SV::default(), Epoch::default(), obs);
    let cn = cd.code_nl_combination();
    assert!(cn.is_some(), "failed to form Cn_narrow combination");
    let cn = cn.unwrap();

    assert_eq!(cn.rhs, Carrier::L1);

    assert_eq!(
        cn.value,
        (Carrier::L1.frequency_hz() * 64.0 + Carrier::L5.frequency_hz() * 128.0)
            / (Carrier::L1.frequency_hz() + Carrier::L5.frequency_hz())
    );
}

#[test]
fn l1_l5_code_if() {
    let obs = vec![
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            pseudo_range_m: Some(64.0),
            ambiguity: None,
            carrier: Carrier::L1,
        },
        Observation {
            snr_dbhz: None,
            phase_range_m: None,
            doppler: None,
            pseudo_range_m: Some(128.0),
            ambiguity: None,
            carrier: Carrier::L5,
        },
    ];

    let cd = Candidate::new(SV::default(), Epoch::default(), obs);

    let c_if = cd.code_if_combination().unwrap_or_else(|| {
        panic!("Failed to form C_if combination");
    });

    assert_eq!(c_if.lhs, Carrier::L5);
    assert_eq!(c_if.rhs, Carrier::L1);

    let (f1, f2) = (Carrier::L1.frequency_hz(), Carrier::L5.frequency_hz());
    let (f1pow, f2pow) = (f1.powi(2), f2.powi(2));

    assert_eq!(c_if.value, (f1pow * 64.0 - f2pow * 128.0) / (f1pow - f2pow));
}