Multi-functional wireless link monitor
A wireless link monitor is configured to operate as an active client that can send and/or receive wireless traffic to and/or from wireless devices-under-test (DUTs) in the network. When the wireless link monitor operates as an active client, the DUTs can send respective wireless traffic to the wireless link monitor. This ensures that the wireless link monitor receives the wireless traffic even when the DUTs transmit their wireless signals narrowly (e.g., in adaptive beamforming technologies).
1. A test instrument for a wireless device-under-test (DUT), comprising:
a processor;
a radio in electrical communication with the processor;
non-volatile memory in electrical communication with the processor, the non-volatile memory storing computer-readable instructions that, when executed by the processor, cause the processor to:
configure the test instrument to function simultaneously as an active client that uses the radio to transmit and receive wireless traffic to and from the DUT and as an inline wireless link monitor that monitors wireless traffic by capturing wireless packets sent between the active client and the DUT;
establish a wireless communication link between the active client and the DUT; and
wherein the inline wireless link monitor captures and streams the wireless packets in packet capture (PCAP) or other packet format that captures packet headers and payload and applies timestamps, and
wherein each test instrument has an internal clock, and the internal clocks are time-synchronized according to a time synchronization protocol;
merge the streams of the wireless packets using the timestamps applied by the synchronized internal clocks;
generate a plot of a wireless communication link characteristic for the DUT using the synchronized merged streams of wireless packets.
2. The test instrument of claim 1 , wherein the active client comprises a wireless access point (AP).
3. The test instrument of claim 1 , wherein the active client comprises a wireless station.
4. The test instrument of claim 1 , wherein the computer-readable instructions further cause the processor to generate a plot of a wireless communication link characteristic.
5. The test instrument of claim 4 , wherein the wireless communication link characteristic includes a received signal strength indicator (RSSI), a data rate, a number of spatial streams, or a channel width.
6. The test instrument of claim 5 , wherein the computer-readable instructions further cause the processor to generate a plot of a physical layer characteristic of the wireless packets.
7. The test instrument of claim 1 , wherein the wireless communication link comprises a Wi-Fi wireless communication link that is compliant with IEEE 802.11.
8. The test instrument of claim 7 , wherein the Wi-Fi wireless communication link is compliant with IEEE 802.11 ax.
9. The test instrument of claim 1 , further comprising a common housing, wherein the processor, the radio, and the non-volatile memory are disposed in the common housing.
10. A system for testing wireless devices, comprising:
a plurality of RF-isolated chambers; and
a plurality of test instruments, in network communication with each other, each test instrument disposed to monitor a respective RF-isolated chamber and comprising:
a processor;
a radio in electrical communication with the processor; and
non-volatile memory in electrical communication with the processor, the non-volatile memory storing computer-readable instructions that, when executed by the processor, cause the processor to:
configure the test instrument to function simultaneously as an active client that uses the radio to transmit and receive wireless traffic to and from a device-under-test (DUT) in the respective RF-isolated chamber and as an inline wireless link monitor that monitors wireless traffic by capturing wireless packets sent between the active client and the DUT;
establish a wireless communication link between the active client and the DUT in the respective RF-isolated chamber; and
wherein the inline wireless link monitor captures and streams the wireless packets in packet capture (PCAP) or other packet format that captures packet headers and payload and applies time stamps, and
wherein each test instrument has an internal clock, and the internal clocks are time-synchronized according to a time synchronization protocol;
merge the streams of the wireless packets using the timestamps applied by the synchronized internal clocks;
generate a plot of a wireless communication link characteristic for the DUT using the synchronized merged streams of wireless packets.
11. The system of claim 10 , wherein the internal clocks of the test instruments are synchronized to an internal clock of the computer.
12. The system of claim 10 , wherein the wireless communication link characteristic includes a received signal strength indicator (RSSI), a data rate, a number of spatial streams, a channel width, or a modulation and coding scheme (MCS) index value.
13. The system of claim 12 , wherein the plot indicates a resource unit allocated for each DUT.
14. The system of claim 10 , wherein each test instrument further comprises a respective common housing and the processor, radio, and non-volatile memory of each test instrument is disposed in the respective common housing.
15. The system of claim 10 , wherein the active client of each test instrument comprises a wireless access point (AP) or a wireless station.
16. The system of claim 10 , wherein the time synchronization protocol comprises a clock synchronization protocol.
17. The system of claim 16 , wherein the clock synchronization protocol comprises a Network Time Protocol or a Precision Time Protocol.
18. A test instrument for a wireless device-under-test (DUT), comprising:
a processor;
a radio in electrical communication with the processor; and non-volatile memory in electrical communication with the processor, the non-volatile memory storing computer-readable instructions that, when executed by the processor, cause the processor to:
configure the test instrument to function simultaneously as an active client that uses the radio to transmit and receive wireless traffic to and from the DUT and as an inline wireless link monitor that monitors wireless traffic by capturing wireless packets sent between the active client and the DUT;
establish a wireless communication link between the active client and the DUT, wherein the inline wireless link monitor captures and streams the wireless packets in packet capture (PCAP) or other packet format that captures packet headers and payload and applies time stamps,
wherein each test instrument has an internal clock, and the internal clocks are time-synchronized according to a time synchronization protocol;
merge the streams of the wireless packets using the timestamps applied by the synchronized internal clocks to provide a synchronized merged stream of wireless packets;
generate a plot of a wireless communication link characteristic; and
when a user selects a data point on the plot, automatically display wireless packet data that corresponds to the data point.
19. The test instrument of claim 18 , wherein the computer-readable instructions further cause the processor to automatically display the wireless packet data in a new window.
20. The test instrument of claim 18 , wherein the active client comprises a wireless access point (AP).
21. The test instrument of claim 18 , wherein the active client comprises a wireless station.
22. The test instrument of claim 18 , wherein the computer-readable instructions further cause the processor to generate a plot of a wireless communication link characteristic.
23. The test instrument of claim 22 , wherein the wireless communication link characteristic includes a received signal strength indicator (RSSI), a data rate, a number of spatial streams, or a channel width.
24. The test instrument of claim 23 , wherein the computer-readable instructions further cause the processor to generate a plot of a physical layer characteristic of the wireless packets.