torchsar.calibration package

Submodules

torchsar.calibration.channel_process module

torchsar.calibration.channel_process.iq_correct(Sr)

IQ Correction performs the I Q data correction

IQ Correction performs the I Q data correction

  • I/Q bias removal

  • I/Q gain imbalance correction

  • I/Q non-orthogonality correction

see “Sentinel-1-Level-1-Detailed-Algorithm-Definition”.

Parameters

Sr (Tensor) – SAR raw data matrix \({\bm S}_r \in {\mathbb R}^{N_a×N_r×2}\)

Returns

Corrected SAR raw data. Flag : dict

Return type

Sr (Tensor)

torchsar.calibration.gain_compensation module

torchsar.calibration.gain_compensation.vga_gain_compensation(S, V, mod='linear', fact=1.0)

vga gain compensation

vga gain compensation

\[\begin{aligned} {\bm F} &= (λ 10^{{\bm V}/20})\\ {\bm S}_{c} &= {\bm F} \odot {\bm S} \end{aligned} \]
Parameters
  • S (torch tensor) – S is an \(N_a×N_r×2\) array, where, \(S[:,:,0]\) is the I signal and \(S[:,:,1]\) is the Q signal.

  • V (torch tensor) – S is an \(N_a×N_r\) or \(N_a×1\) VGA gain array, the gain values are in dB unit.

  • mod (str, optional) – compensation mode (the default is ‘linear’)

  • fact (number, optional) – fact is the factor \(\lambda\) (the default is 1.0)

Returns

compensated signal, \(N_a×N_r×2\) array.

Return type

torch tensor

torchsar.calibration.multilook_process module

torchsar.calibration.multilook_process.multilook_spatial(Sslc, nlooks)

spatial multilook processing

spatial averaging in azimuth or range direction.

Parameters
  • Sslc (Tensor) – Processed single look complex (or intensity) sar data tensor with size \(N_a×N_r\).

  • nlooks (tuple or list) – The number of looks in azimuth and range direction, [na, nr] or (na, nr).

Returns

Processed multi-look complex tensor.

Return type

Smlc (Tensor)

Module contents