1. Multi-chamber testbed for Wi-Fi/NR-U coexistence testing
July 17, 2019
Leigh Chinitz, octoScope

2. Both Wi-Fi and NR-U likely to coexist in the 6 GHz band

3. Both Wi-Fi and NR-U likely to coexist in the 6 GHz band

4. Various coexistence scenarios will need to be explored
Simple ones
…and much more complex ones 1
root 2

5. Even simple scenarios will have many possible variations

6. Coexistence testing must be defined in the context of a testbed
Many options are available
Conducted testing
Large anechoic chamber testing
Radiated open air testing
Multi-chamber testing
The testbed must:
Be able to create the test scenarios of interest (EXTENSIBLE)
Be able to produce repeatable results (REPEATABLE)
The testbed should:
Be accessible to anyone who wants to use it (ACCESSIBLE)
For some good work on wireless coexistence, we strongly recommend reading the ANSI C63.27, “American National Standard efor Evaluation of Wireless Coexistence”
It defines “coexistence” as well as other relevant terms, and provides a framework for understanding the probability that two wireless networks can coexist.

7. WFA testbed for coexistence testing of LTE-U and Wi-Fi
A full mesh,
multi-chamber
testbed
See

8. octoScope testbed for Wi-Fi Alliance coexistence testing
Co-existence testbed, as implemented

9. Multi-chamber co-existence testbed
Makes possible the “simple” configurations with one AP/STA and one gNB/UE pair
Full control over “distances” allows for all combinations of that simple topology to be tested, easily
Tests can easily look at more than one topology
Changed via SW
Shielded Enclosure
PA_6 AP
PA_4 UE
PA_1
gNB
PA_2
PA_5
STA
PA_3
Programmable Attenuator

10. Even the complex scenarios can be supported
3-node mesh and STA 1 2
root
gNB and UE

11. Multi-chamber testbed a solid choice for coexistence testing
Extensible
Accessible
Repeatable

12. Boston area headquarters 305 Foster Street Littleton, MA 01460 USA
Tel:
California office 780 Montague Expressway, Building 1 San José, CA 95131  USA
Tel:

13. Backup
Testbed Examples

14. Personal testbed
Traditional testbed
AP testbed devices
DUT
sniffer
STA testbed devices

15. Generic certification testbed
Wireless Sniffer
UCC = universal CAPI control
CAPI = common application programming interface
Sigma
UCC …
WFA
EMT
DUT
RF combiner
Sigma AP
Control Agent
Ethernet Switch
Sigma
PC End Point
RADIUS
Server
Ethernet Switch
Ethernet filters
Control Ethernet
Test Ethernet
Ethernet Switch

16. Example testbed – ax TTG
Testbed APs are cabled in the top chamber
Testbed STAs are cabled in the bottom chamber
DUT and sniffer are OTA coupled in the middle chamber
High gain antennas (log periodic) offer full dynamic range when coupled from on chamber to another via a programmable attenuator
AP testbed devices
DUT
sniffer
STA testbed devices