tb_beamform_delay_sum — 2D typed op

数据种类:beatcubesignal

调用:fullseye.apply(img, "tb_beamform_delay_sum", a=0.5, b=0.5)(2-D 的模型是一张图 + 两个标量旋钮 a,b∈[0,1])

tb_beamform_delay_sum: input → output

*图为在 128×128 合成输入上实际运行的输出。左为输入,右为输出。点云以俯视散点显示(亮度 = z),一维序列为折线,体数据为沿 z 的最大值投影,视频为中间帧,复数图像为幅值;无法成像的返回值直接显示数值。*

扫描旋钮 a(0.1 / 0.5 / 0.9,另一旋钮取默认):

tb_beamform_delay_sum: knob a sweep (docs site)

*旋钮 b 不改变输出(实测: 0.1 / 0.5 / 0.9 相同)。*

阶段(前置算子 → 本算子,从左到右):

tb_beamform_delay_sum: stages (docs site)

换别的图像(合成场景 / 照片 / 硬币。上排为输入,下排为对应输出。旋钮取默认):

tb_beamform_delay_sum: other inputs (docs site)

用法

针对单个距离-多普勒单元的延迟求和(Bartlett)角度谱。

> 以下的详细说明为原文 —— 摘要与标题已翻译。

Takes the per-antenna complex value at a single range-Doppler cell — by

default the strongest one — and for each steering angle removes the expected

inter-element phase and sums:

`P(theta) = |sum_k conj(exp(1j*2*pi*d*k*sin(theta)/lambda)) * x_k|^2`

which peaks at the true arrival angle with value `(N_a * |a|)^2`: the

aperture gives `N_a in amplitude, N_a^2` in power. That is the exact

ground truth the tests pin. Measured with 8 elements: the peak power is

bit-exactly `(N_a*N_c*N_s)^2 = 268435456` (relative error 0.0), and

sweeping the true angle from -80 to +80 degrees in 5-degree steps (33 cases)

the reported angle matches the truth with a maximum error of 0.0 degrees.

The steering grid defaults to `arange(-90, 90.5, 1.0). normalize=True`

divides by `N_a^2 * N_c^2 * N_s^2` so that a unit-amplitude bin-centred

target peaks at 1.0.

Returns a 1-D float64 array of powers, one per grid angle — a plain signal,

so :mod:dsp's `find_peaks and :mod:funct1d`'s smoothing apply to it.

Use :func:beamform_doa if you want the angles themselves.

*range_bin* is a plain `0..N_s-1` index; *doppler_bin* is the signed

velocity bin, the same convention :func:range_doppler_peaks reports, so a

detection can be handed straight back in. Both or neither — half a cell

address raises rather than quietly beamforming the strongest cell instead.

Raises `ValueError`: no aperture — either a single element, or many

elements packed into under ~0.28 wavelengths. In both cases the spectrum is

flat to within float noise and `argmax` returns the first grid angle, i.e.

a confident report of -90 degrees that is pure tie-breaking (measured: 8

elements at 1e-12 m spacing gave a peak-to-trough spread of exactly 0.0 and

reported -90.0). Also: an all-zero cube or an all-zero selected cell; only

one of *range_bin* / *doppler_bin*; an out-of-bounds bin index; an angle grid

outside `[-90, 90]`; an FFT that overflows to NaN; plus the usual cube and

scalar refusals.

Typed bridge of the rangedoppler op `beamform_delay_sum into the 2-D evolution registry: the same implementation, called under the op(v, a, b) convention. a drives wavelength_m (default 0.0038934); b` is unused.

参考(示例数据・文献)

• 示例数据目录(下载 URL / 许可证) —— 2-D 用 skimage.data(BSD/公有领域)加合成图,3-D 给出真实数据源(Stanford/PDS 等)的下载 URL。

• 算子来历与参考文献 —— 该算子族所依据的研究/方法出处。

在 Studio 中试试

下面的程序已确认可以运行(与图相同的输入)。在 Studio 帮助中,此块会变成按钮,可当场加载并运行。

img_to_beatcube 0.50 0.50
tb_beamform_delay_sum 0.50 0.50

▸ Load this pipeline  ·  Load & run

可运行的示例(实际调用该算子并已验证的样例)

下面的示例调用的是底层账本算子 beamform_delay_sum。此桥接算子只是把同一实现适配为 fn(v, a, b) 约定,行为完全相同(只是调用形式不同)。

fmcw_range_dopplerpy -3.11 examples/fmcw_range_doppler.py

poc_multibeam_bathymetrypy -3.11 examples/poc_multibeam_bathymetry.py

类型可衔接的下一个算子(可接受 signal 作为输入)

identity · tb_create_funct_1d_array · tb_smooth_funct_1d_gauss · tb_smooth_funct_1d_mean · tb_derivate_funct_1d · tb_integrate_funct_1d · tb_zero_crossings_funct_1d · tb_abs_funct_1d

同类别(typed)

tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal · tb_voxel_grid_downsample


*Provenance: ops.py — 2D 算子登记表。本条目由 tools/opdocs.py md 自动生成(请勿手工编辑)。*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.