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Calibrating TR-398 Issue-2 and Mesh on a 4-Chamber Setup

Goal: Setup and run a TR-398 Issue 2 test for an AP using a 6-radio version of the LANforge CT523c or similar system in order to test how well the AP can handle the various test cases specified in the TR-398 Issue 2 test document.

In this test scenario, a LANforge cluster (of a 1 523c and 3 521as) is used to emulate different station and AP scenarios and generate and receive traffic with an AP. This example assumes user has some experience with Chamber View, and has an appropriate LANforge system (fit for TR-398 Issue 2), programmable attenuators like the CT714 and some isolation chambers like the CT820a and CT840a. Please contact for assistance in setting up the TR-398 testbed.

  1. Configure Chamber View for TR-398 and Similar Tests.
    1. Open Chamber View by clicking on the 'Chamber View' button in the LANforge-GUI. If you have an appropriate scenario already created, please skip to the next section, otherwise you will need to build a scenario that matches your system. You can right-click in Chamber View to create various objects. This cookbook will use the Chamber View scenario seen below. screenshot
    2. Create a Device Under Test (DUT) Profile that matches your AP. The BSSID is important to configure so that LANforge knows when it is connected to the correct AP. In a mesh scenario, you will create 3 DUT objects, one for each of the mesh AP chambers. screenshot
    3. Create a chamber object to hold the DUT, and add the DUT to that chamber. If you have no chambers, you can create a fake chamber, but your test will not be isolated and may not function as desired. The turntable configuration is different for different models of chambers, this example (bare IP address) is for the CT840a chamber. screenshot
    4. Create a chamber object to hold the LANforge system, and add the LANforge to it. Add connections from this chamber to the DUT chamber, specifying the proper Attenuator modules. Please note we use the 'OTA' attenuation floor since we have OTA connection between DUT and antennas inside the DUT chamber. Please view our other cookbook on setting up attenuator connections in LANforge. screenshot
    5. Configure a Chamber View Scenario and add the STA profile (mapped to desired wiphyX radio and DUT). Add an upstream profile mapped to DUT LAN side (or possibly WAN side if that is more appropriate for your DUT). screenshot
  2. For TR398 tests, the DUT AP's front should face the antennas for the Group-1 stations. Or, optionally, one can use the Advanced configuration tab to specify the default turntable angle for non rotational tests.
  3. Open Chamber View by clicking on the 'Chamber View' button in the LANforge-GUI. Load appropriate scenario. Apply the Scenario, then Build the scenario. screenshot
  4. Select the TR-398-Issue-2 test from Tests dropdown in the right panel. Then click Run Test. The following window below should pop up. In the Settings tab, set slots 'Selected DUT 5G', 'Selected DUT 2G', and 'Selected DUT 6G' the according BSSIDs found in the 'Root' Chamber. Also set the upstream port. In this example, the upstream port is the eth2 port on the LANforge in Mobile Stations chamber. screenshot
  5. Configure the Virtual Sta Radio Settings tab.
    1. Select the Virtual Sta Radio Settings tab. This tab is for radios that can have virtual stations on them (either AC, N, some AX). Notice that there are 3 groups here, this will be the 3 slots of radios (Slots 2, 3, 4) in the Mobile Clients Chamber. Visit the pictures in the next 2 steps to see close ups of the attenuator diagram that has the slots. Slot 2 (Group 0) has W0 ad W1 (wiphy0 and wiphy1). Slot 3(Group 1) has W2 and W3 (wiphy2 and wiphy3). Slot 4 (Group 2) has W4 and W5 (wiphy4 and wiphy5). Leave the '2.4Ghz RSSI 0 Atten' and '5Ghz RSSI 0 Atten' blank, those will be auto calculated when we calibrate the attenuators. Lastly, fill out the attenuator modules column (with the correct serial numbers that relate to each group). All these attenuators will be the TR-398 section of the attenuator stack. In this case, those are attenuators T1, T2 and T3. These attenuators are also all connecting the Node 3/Root chamber to the Mobile Clients chamber. Match the according attenuator to each group on the attenuator diagram. Fill out all the dropdowns under 'Attenuator Modules' for ports 0-3 on the matching attenuator. Select the 'Use Virtual AX Stations' checkbox. screenshot
    2. Below is the attenuator diagram of the 4-chamber setup in the example. Another name for the Node-3 Chamber is the Root chamber. screenshot
    3. Below is a closer look at the bottom right box of the attenuator diagram in the step above. screenshot
    4. Below are the serial numbers of the attenuator stack. They are stacked in the same order as the attenuator diagram. screenshot
  6. Configure the 802.11 AX Settings (1 & 2) tabs. Please contact for assistance in filling out these tabs. These settings only apply to AX capable radios that do not support virtual stations.
  7. Configure the Mesh Settings and Mesh Settings 2 tabs. If the test bed being setup has no need for Mesh, please skip this step.
    1. Select the Mesh Settings tab. The picture below is a final version of the calibrated mesh setup. In an un-calibrated version (yours), all the rows in the 'RSSI 0 Atten' columns will be empty. Fill out select the 2.4Ghz and 5Ghz BSSIDs for both Node 1 and Node 2 Chambers in the top section. Fill out the 'Atten Modules' column for each group (using ports 0-3 for each attenuator). To find out the correct attenuator, trace the attenuator diagram to find out which attenuator connects which 2 Chambers. In Group 1 (in this section), use the attenuator and radios used in 'Group 2' of the Virtual Sta Radio Settings tab. This attenuator is both TR398 and Access (A3/T1), so it belongs in both Virtual Sta Radio Settings and Mesh Settings screenshot
    2. Fill out the Mesh Settings 2 tab similarly to Mesh Settings 1 screenshot
  8. Click on the Advanced Configuration tab. Set 2.4GHz channel and 5GHz channel to '-1'/ AUTO. AUTO won't work for all cases (like the ap-coex test), but will work for most of them. screenshot
  9. Calibrate Zero Attenuation RSSI for all chamber to chamber connections. This also verifies attenuators are connected and functioning as expected.
    1. Start by setting the LANforge in the center of all the chambers, with all the antennae pointing directly to the LANforge. We are calculating 0 atten against the LANforge.
    2. Calibrate the 802.11AC attenuators. Only select this checkbox to ensure that the calibration goes OK. screenshot
    3. In the image below, run each of the checkboxed boxes one at a time, until all are run. screenshot
  10. At this point, all the 0 Atten values should be filled out (In Virtual Sta Radio Settings and Mesh Settings 1 & 2 tabs).
  11. Run a TR-398 Issue 2 throughput test. Select the 6.2.2 Maxiumum Throughput checkbox to run the test. After verifying the throughput test is working as expected, select and run other tests as desired. screenshot
  12. When the test is complete, click the Save HTML button to save an HTML report and generate the PDF. The PDF file will be linked from the HTML page. Another option is to click 'Save PDF' and the browser will be directed to open the pdf file directly. Please see this passing example TR-398 Issue 2 Maximum Throughput Test Report .

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