coupling_loss_db#

sionna.sys.coupling_loss_db(path_gain_db, precision: Literal['single', 'double'] | None = None, device: str | None = None) → torch.Tensor[source]#

Computes the coupling loss from a path gain in dB.

The coupling loss \(\mathrm{CL}_{b,u}\) between BS \(b\) and UT \(u\) is the negative path gain,

\[\mathrm{CL}_{b,u}[\mathrm{dB}] = -G_{b,u}[\mathrm{dB}],\]

where \(G_{b,u}\) includes all gains and losses between transmitter and receiver. It is used in the link budget

\[P_{r,b,u}[\mathrm{dBm}] = P_{\mathrm{tx},b}[\mathrm{dBm}] - \mathrm{CL}_{b,u}[\mathrm{dB}].\]

This convention follows the coupling-loss definition used for 3GPP system calibration in Section 7.8 of [TR38901V160100]. Coupling loss is one of the Phase 1 calibration metrics and is also used as input for the geometry SIR, geometry SINR, and wideband SIR metrics.

Parameters:

  • path_gain_db – Path gain [dB].

  • precision (Literal['single', 'double'] | None) – Precision used for internal calculations and outputs. If set to None, precision is used.

  • device (str | None) – Device for computation. If None, device is used.

Outputs:

coupling_loss – Coupling loss [dB].

Examples

from sionna.sys import coupling_loss_db

cl = coupling_loss_db(-120.0)
print(cl)
# tensor(120.)