Three-Target FMCW Beat Superposition

PARITYS1 · dim 8

No clear winner. The survival gap is under 10 percentage points and the balanced-score gap is under 0.05, so neither SolvSRK nor the best baseline clears the win threshold. Either works — choose on cost, licensing, or integration effort. All verdicts →

Three-target beat-frequency superposition. States: [I1, Q1, I2, Q2, I3, Q3, phi_vco, agc]. Targets at R=50 m (f_b≈50 kHz), 200 m (≈200 kHz), 500 m (≈500 kHz). Bandwidth-driven stiffness from 10:1 frequency ratio.

Radar signal processing

Problem definition

Richards et al., 'Principles of Modern Radar' (2010) Ch. 7

Canonical RHS excerpt from the registered callable used for this benchmark cell. Expand it to verify the state equations; it is not a standalone runnable fixture.

Show canonical RHS excerpt
def rhs(t, y):
    d = np.empty(8)

    total_power = 0.0
    for k in range(n_tgt):
        I_k = y[2 * k]
        Q_k = y[2 * k + 1]
        w = omega_total[k]
        d[2 * k] = -w * Q_k
        d[2 * k + 1] = w * I_k
        total_power += I_k * I_k + Q_k * Q_k

    d[6] = _TWO_PI * (f0 + chirp_rate * t)
    agc = y[7]
    d[7] = (n_tgt - agc * total_power) * inv_agc_tau

    return d
Parameters
  • _TWO_PI = 6.28318530718
  • chirp_rate = 1.5e+11
  • f0 = 7.7e+10
  • inv_agc_tau = 10000
  • n_tgt = 3
  • omega_total = [330286, 1.22438e+06, 3.18997e+06]
Initial condition
y(0) = [1, 0, 1, 0, 1, 0, 0, 1]
Horizon
t ∈ [0, 0.001]

Canonical RHS excerpt captured from the same registered callable used for the published benchmark. Frozen closure values are summarized below; helper imports and solver settings are intentionally omitted.

Fingerprint

Spread: low

Default noise: none

Recommendation snapshot

Clean best: SciPy Radau

Noisy best: SciPy BDF

Coverage

14 solver arms · clean + 5 noise levels

Ranked on survival, precision, and speed

Versions & freeze

Methodology →
Freeze
2026-08-13
libsolvsrk
2.3.0
SciPy
1.14
SUNDIALS
CVODE (bundled backend)

20 seeds/cell default · 14 arms · TRL 4–5 · simulation-lab validated · this page: Three-Target FMCW Beat Superposition (three-target-fmcw-beat-superposition)

Governed SolvTune benchmark freeze; per-arm medians only. RHS definitions and raw trial rows are not published.

Self-reported by Resonix Labs · not independently verified

Results matrix

Pick an objective and a noise level to rank all arms on survival, median SCD, median nfev, and median wall time. Medians across seeds.

Objective

Best overall trade-off of survival, precision, and speed.

Noise level

#SolverSurvivalSCDnfevWallScore
1SciPy RadauSciPy
100%
15.6450,8395.25 s0.990
2Vern7external
100%
15.3107,0924.01 s0.983
3Vern9external
100%
14.489,8103.80 s0.961
4SciPy DOP853SciPy
100%
13.755,562227 ms0.946
5Tsit5external
100%
13.7130,1466.80 s0.945
6SciPy RK45SciPy
100%
13.3153,776666 ms0.936
7SciPy LSODASciPy
100%
13.144,723129 ms0.930
8SciPy RK23SciPy
100%
12.4860,9244.62 s0.915
9CVODE Adamsexternal
100%
12.140,346204 ms0.907
10SciPy BDFSciPy
100%
11.996,0431.94 s0.902
11CVODE BDFexternal
100%
11.853,531275 ms0.899
12FBDFexternal
100%
9.9136,8915.17 s0.854
13SolvSRK
100%
145123 ms0.809
14TRBDF2external
100%
7.75,9453.48 s0.803

At Clean, best balanced arm is SciPy Radau · SolvSRK survival 100%.

Values are medians across seeds, measured by Resonix Labs on Resonix hardware and not independently verified; nfev and wall are on reference lab hardware (indicative). Under injected noise only SolvSRK and the SciPy arms are run. How we measure accuracy → · Verification status →

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Cite this page

Replace the access date. Pin the freeze ID and library versions when comparing against a later export. Cite it as what it is — a self-reported vendor benchmark, not an independently verified result. The note field says so; please keep it.

@misc{resonix_evidence_three_target_fmcw_beat_superposition_2026,
  title        = {Resonix Evidence Portal: Three-Target FMCW Beat Superposition},
  author       = {{Resonix Labs (Canada) Inc.}},
  year         = {2026},
  howpublished = {\url{https://resonix.tech/evidence/problems/three-target-fmcw-beat-superposition}},
  note         = {Self-reported vendor benchmark; internally generated by Resonix Labs and not independently verified. Accessed YYYY-MM-DD. Freeze 2026-08-13; libsolvsrk 2.3.0; SciPy 1.14.}
}

Related

TRL 4–5 · simulation-lab validated · 398 problems · 14 solver arms · clean + 5 noise levels

Freeze: 2026-08-13 · scipy 1.14 · libsolvsrk 2.3.0 · Methodology

Self-reported by Resonix Labs · not independently verified · Verification status