Fig. 4From: Residual energy maximization for NOMA-enabled UAV-assisted data collection network: trajectory optimization and resource allocationa NOMA grouping results at t = 10ms. b NOMA grouping results at t = 20ms. Square—group1—the location of IoTDs within NOMA group 1; diamond—group2—the location of IoTDs within NOMA group 2; left triangle—group3—the location of IoTDs within NOMA group 3 and right triangle—group4—the location of IoTDs within NOMA group 4 star—UAV—the location of UAVBack to article page