https://devzone.nordicsemi.com/f/nordic-q-a/41430/i-need-help-developing-a-gatewayHi. I am developing a gateway using SDK15 and nRF52840. I&#39;m advertising 4 devices every 20ms. Theoretically, it should be scanned 50 times each, but in reality it is scanned from 6 to 12. At this time, the gateway is set up as follows. /** en-USTelligent Community 13Mon, 10 Dec 2018 22:13:58 GMThttps://devzone.nordicsemi.com/thread/161086?ContentTypeID=1Mon, 10 Dec 2018 22:13:58 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9cf1ee1a-5335-4e0e-805f-8d3385ef0fe8David Edwin<p>I ran a simulator test for 4 nodes to gateway, it appears that each node needs to transmit a packet about 5 times (worst case) before it is detected. This means your assumption of gateway detecting 50 packets of each node is optimistic.&nbsp;&nbsp;<img alt="Sim for 4 nodes to gw at 20ms advertising" src="https://devzone.nordicsemi.com/resized-image/__size/320x240/__key/communityserver-discussions-components-files/4/sim_5F00_4_5F00_nodes_5F00_5_5F00_packets_5F00_needed_5F00_per_5F00_data.PNG" /></p> <p>Improvements possible:</p> <p>Use passive scanning in the gateway and non-connectable advertising in the nodes, this should improve the scanner performance a bit.</p><div style="clear:both;"></div>