Low Latency C&C and Video Streaming with the Nvidia Jetson Nano: Smart Radio Configuration

Low Latency C&C and Video Streaming with the Nvidia Jetson Nano: Smart Radio Configuration

Smart Radio Configuration

In this section, we describe simple steps to setup the Smart Radio for video streaming. If you are not sure how to make any of these configuration settings, then please consult the Smart Radio Configuration Guide.

IP Configuration

The Jetson Nano is pre-configured as a DHCP client. However, by default, the Smart Radio does not have the DHCP server enabled. So, we will simply enable the DHCP server on one of the Smart Radios. The DHCP server should be enabled on the WAN2 interface. In the GUI, navigate to Network → Interfaces and EDIT the WAN2 interface. Wait for the configuration page to load, then scroll to the bottom and click Setup DHCP Server. The default settings are ok, so just click Save & Apply. At this point you should make sure all nodes on the network are setup as DHCP clients. This is true by default for the Smart Radio which are DHCP clients, but also have a fixed IP address.

Figure 3 – DHCP Configuratoin

You can find the IP addresses of all nodes on the network by logging into the Smart Radio over SSH and using the address resolution protocol. You can identify connected devices by their hardware address.

root@smartradio-301a4e2006:~# arp
IP address       HW type   Flags   HW address            Mask     Device     0x1       0x0     b0:25:aa:2d:d3:8e     *        br-lan     0x1       0x2     00:04:4b:e6:b4:76     *        br-wan     0x1       0x2     b0:25:aa:2d:d3:8e     *        br-wan     0x1       0x2     00:30:1a:4e:20:0a     *        br-wan      0x1       0x0     b0:25:aa:2d:d3:8e     *        br-wan

Note that the above steps apply for both WDS AP/Client and Mesh modes.


Setup Steps

1.       Switch to WDS AP/Client Mode. This is the recommended mode for point-to-point or star networks. The AP should be at the center of the star network, but in a point-to-point network, you may find it more convenient having the AP as the remote device. Note that all traffic must pass through the AP. The easiest way to switch to WDS AP/Client mode is using the simpleconfig menu in the web GUI.

2.      In the AP, turn on the DHCP server on WAN2.

3.      Non WiFi-Compliant Mode. This step only applies to RM-2450 model to avoid the interference from other WiFi nodes in the area. You can switch to any channel bandwidth other than 20/40 MHz to avoid WiFi compliance. This mode tends to lead to a more stable latency.

4.      In the Xtreme models, reduce the distance setting to the maximum required in your application. This setting is found in the advanced tab of the wireless configuration.

5.      Keep the TX Power in Auto mode. This provides the best range.

6.      Make sure that the Smart Radio link is able to support the required throughput for the desired video resolution. Iperf can be used to measure throughput. We suggest to keep an extra 50% headroom for the interference margin. Refer to Table 1 for throughput requirements.

7.       In the differentiated services UI page, enable video optimization, and add a new rule to send packets originating from the IP address of the IP camera to the video queue (screenshot below). In our example, we are simply putting all traffic coming from the IP camera in the video queue. It is possible to filter traffic by the IP addresses, protocol, or port number. This is described in more detail in the last section.

8.      Note that Doodle Labs Mesh Rider uses special radio parameters for this queue to optimize the video transmission over wireless medium in high interference areas.