design op• Data kinds: none → table (an op determined by its arguments alone — it takes no image or data input)
• Call: import rangedoppler; rangedoppler.fmcw_design(n_samples=64, n_chirps=32, sample_rate_hz=10000000.0, slope_hz_per_s=20000000000000.0, chirp_period_s=5e-05, wavelength_m=0.0038934, n_antennas=1, element_spacing_m=None) (or opsrangedoppler.get("fmcw_design"))
Bin widths, resolutions and aliasing limits of an FMCW configuration.
The paper answer to "will this waveform see what I care about?", with no data
and no simulation — the stance :mod:visiondesign takes for optics. Every
number is closed form:
============================== ============================================
quantity formula
============================== ============================================
swept bandwidth `B = S * N_s / f_s`
range bin / resolution `dR = c / (2B) = c*f_s / (2*S*N_s)`
max unambiguous range `R_max = c*f_s / (2S) (= N_s * dR`)
beat frequency per metre `2S/c`
velocity bin / resolution `dv = lambda / (2*N_c*T_c)`
max unambiguous velocity `v_max = lambda / (4*T_c) (= N_c*dv/2`)
Doppler phase per (m/s) `4*pi*T_c / lambda` rad per chirp
coherent processing interval `N_c * T_c`
max unambiguous angle `asin(lambda / (2d))`
angular resolution (boresight) `0.886 * lambda / (N_a * d)`
============================== ============================================
The two "max" figures are hard aliasing limits, and they are the same
numbers :func:fmcw_beat_simulate refuses to cross. The angular resolution
is the 3 dB beamwidth of a uniform linear array at boresight (Van Trees 2002,
§2.4); it widens as `1/cos(theta)` off boresight, which this does not report
because it is a function, not a number.
`cube_elements and cube_mebibytes` are included because "small input,
huge allocation" is the failure mode of this family: the cube grows as
`N_a * N_c * N_s` and complex128 is 16 bytes a sample.
Returns a `dict. Raises ValueError` on a non-positive or non-finite
parameter, a wavelength over :data:MAX_WAVELENGTH_M, or a count outside its
cap.
>>> d = fmcw_design()
>>> round(d["range_bin_m"], 6), round(d["max_unambiguous_velocity_ms"], 6)
(1.171064, 19.467)
• fmcw_range_doppler family guide
• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).
• Operator provenance and references — the sources of the research/methods this op family came from.
• The canonical algorithm (author, year) and its uses are named in the family usage guide above.
• fmcw_range_doppler — py -3.11 examples/fmcw_range_doppler.py
table as input)—
design)—
*Provenance: rangedoppler.py — RANGEDOPPLER operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.