Figure 9
From: Multiplexed Millimeter Wave Communication with Dual Orbital Angular Momentum (OAM) Mode Antennas

The signals are monitored by a digital communication analyzer. The data A (blue solid line) are the signals when the modulated signal is launched into to the l = +3 port of the transmitting antenna, the data B (red dash line) are the signals A when the modulated signal is launched into the l = –3 port of the transmitting antenna.