Add taper support and refactor array-factor calculation

[George-Guryev-flxcmp]

Add taper support to RectangularAntennaArrayCalculator; refactor array factor computation for clarity and efficiency.

• Implemented taper integration
• Refactored AF calculation
• Updated tests and docs

[greptile-apps]

_{4 files reviewed, 7 comments}

_{Edit Code Review Bot Settings | Greptile}

[github-actions]

Diff Coverage

Diff: origin/develop...HEAD, staged and unstaged changes

• tidy3d/plugins/microwave/array_factor.py (94.2%): Missing lines 655,704,918,938,958,978,1031,1195

Summary

• Total: 137 lines
• Missing: 8 lines
• Coverage: 94%

tidy3d/plugins/microwave/array_factor.py

  651             amp_z = amp_z[:, None, None]
  652 
  653         # Tapers with non-separable amplitude weights are not supported by this function
  654         else:
! 655             raise ValueError(f"Unsupported taper type {type(self.taper)} was passed.")
  656 
  657         # Calculate individual array factors in x, y, and z directions
  658         af_x = np.sum(
  659             amp_x * exp_x,

---

  700         amps = self.taper.amp_multipliers(self.array_size)
  701 
  702         # ensure amplitude weights are in format tuple[ArrayLike, ]
  703         if len(amps) != 1:
! 704             raise ValueError(
  705                 "Non-cartesian taper was expected. Please ensure a valid taper is used."
  706             )
  707 
  708         # compute array factor: AF(theta,f) = sum_{x,y,z} amp(x,y,z) * exp_x(x,theta,f)*exp_y(y,theta,f)*exp_z(z,theta,f)

---

  914         -------
  915         ArrayLike
  916             1D array of Hamming window weights.
  917         """
! 918         return hamming(N)
  919 
  920 
  921 class BlackmanWindow(AbstractWindow):
  922     """Standard Blackman window for tapering or spectral shaping."""

---

  934         -------
  935         ArrayLike
  936             1D array of Blackman window weights.
  937         """
! 938         return blackman(N)
  939 
  940 
  941 class BlackmanHarrisWindow(AbstractWindow):
  942     """Standard Blackman-Harris window for tapering or spectral shaping."""

---

  954         -------
  955         ArrayLike
  956             1D array of Blackman-Harris window weights.
  957         """
! 958         return blackmanharris(N)
  959 
  960 
  961 class HannWindow(AbstractWindow):
  962     """Hann window with configurable sidelobe suppression and sidelobe count."""

---

  974         -------
  975         ArrayLike
  976             1D array of Hann window weights.
  977         """
! 978         return hann(N)
  979 
  980 
  981 class ChebWindow(AbstractWindow):
  982     """Standard Chebyshev window for tapering with configurable sidelobe attenuation."""

---

  1027         -------
  1028         ArrayLike
  1029             1D array of Kaiser window weights.
  1030         """
! 1031         return kaiser(N, self.beta)
  1032 
  1033 
  1034 class _Taylor1D(AbstractWindow):
  1035     """Taylor window with configurable sidelobe suppression and sidelobe count."""

---

  1191             Weights sampled from the Taylor window.
  1192         """
  1193         if self.mode == "1d":
  1194             if not isinstance(arg, int):
! 1195                 raise TypeError("1D Taylor expects integer size.")
  1196             return _Taylor1D(sll=self.sll, nbar=self.nbar).get_weights(N=arg)
  1197         else:
  1198             locs = np.asarray(arg)
  1199             return _TaylorRadial(sll=self.sll, nbar=self.nbar).get_weights(p_vec=locs)

---

[dbochkov-flexcompute]

Great start! Still not sure about at, sll, nbar, etc vs attenuation, side_lobe_level, num_constant_sidelobes, etc. @yaugenst what's our policy on using pydantic alias feature on frontend?

[weiliangjin2021]

Very nice work!

[weiliangjin2021]

to be removed?

[weiliangjin2021]

one missing "-"?

[weiliangjin2021]

more informative to name the field "attenuation", unless "at" is widely used in the field.

[weiliangjin2021]

maybe isotropic_window for clarity?

[weiliangjin2021]

avoid repetition with a for loop, e.g.

amps = (window.get_weights(effective_size[ind]) if window is not None
            else np.ones(effective_size[ind]) for ind, window in enumerate([self.windows_x, self.windows_y, self.windows_z]))

[weiliangjin2021]

i think we should raise an error if TaylorWindow's mode is not radial, rather than changing it silently.