pam_gray

sionna.phy.mapping.pam_gray(b: numpy.ndarray) → int

Maps a vector of bits to a PAM constellation point with Gray labeling.

This recursive function maps a binary vector to Gray-labelled PAM constellation points. It can be used to generate QAM constellations. The constellation is not normalized.

Parameters:

b (numpy.ndarray) – Array with binary entries of shape [n].

Outputs:

point – int. PAM constellation point taking values in \(\{\pm 1,\pm 3,\dots,\pm (2^n-1)\}\).

Notes

This algorithm is a recursive implementation of the expressions found in Section 5.1 of [3GPPTS38211]. It is used in the 5G standard.

Examples

import numpy as np
from sionna.phy.mapping import pam_gray

b = np.array([1, 0])
print(pam_gray(b))
# -1