LTE/Wi-Fi Coexistence Testbed for Unlicensed Spectrum Characterization
"Explore the benefits of testing real devices in an Unlicensed LTE/Wi-Fi coexistence testbed to inform decisions on coexistence mechanisms. Learn about the motivations, common test scenarios, and goals of this project for LTE-LAA development units. Discover the importance of fair sharing data and neutrality in testing platforms for both Wi-Fi and Unlicensed LTE technologies."
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
July 2015 doc.: IEEE 802.19-15/0055r3 Unlicensed LTE/WiFi Coexistence Testbed Date: 2015-07-06 Authors: Name Ben Lampert Affiliations Address octoScope Phone 9712182444 email Ben.Lampert@octoScope. com Akhila.Nandgopal@octoS cope.com Akhila Nandgopal octoScope 17745786774 Submission Slide 1 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Abstract Propose an Unlicensed-LTE/Wi-Fi testbed for coexistence characterization. Submission Slide 2 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Common Testbed Motivation Everyone benefits from testing real devices and applications that would be difficult to recreate in a simulation Wi-Fi community will benefit from hands on experience with Unlicensed LTE to evaluate their applications and devices 3GPP will benefit by alleviating concerns about coexistence mechanisms and using data to inform LTE- LAA decisions A neutral test platform can provide fair sharing data for both Wi-Fi and Unlicensed LTE to help inform decisions from both groups Submission Slide 3 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 LTE-LAA Benefits from Participating in Testing Testbed will allow for any early LTE-LAA development units to be tested (ie, rack mounted) Can use existing Wi-Fi/LTE-U devices to help drive LTE-LAA decisions based on real interactions. Best Coexistence Mechanisms Energy detection thresholds Real device traffic patterns and application behavior Channel selection algorithms Good LTE-U Coexistence data already taken [1], input from Wi-Fi community can only help inform decisions Submission Slide 4 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Possible Test Scenarios Testbed to define and validate fairness Wi-Fi/LTE, Wi-Fi/Wi-Fi, LTE/LTE Fairness criteria including VoIP, Packet Jitter, Airtime, Throughput, etc Neutral Testbed for vendors (LTE/Wi-Fi) to test particular scenarios Hidden Nodes High Density Environments Operation in different CCA detection thresholds Application/vendor specific tests Adjacent/Co-Channel Interference Submission Slide 5 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Intro to Unlicensed-LTE Testbed Goal was to design a RF environment that was flexible for testing variety of Unlicensed LTE/LTE-LAA/LTE-U/Wi-Fi scenarios. Based on our understanding the requirements for a wireless contention test bed are: High Isolation from external devices Good control over power levels across devices Multipath Environment to test MIMO STA s Ability to test real applications (VoIP, Video streaming, file transfer, etc) Flexibility to test high channel load environments Repeatability and in a lab environment Focused on simple scenario: Wi-Fi AP-STA baseline with added Wi-Fi or LTE eNB traffic Submission Slide 6 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Coexistence Testbed with multipath Goals: -OTA (Over the air) Coexistence testing -Multi Path Emulation (Can be bypassed) -Wi-Fi traffic to clients benchmarked before and after LTE introduced -Wi-Fi sniffer helps diagnose channel loading/packet timing -Can be used to test real life applications (video streaming, VoIP, etc). -Attenuation helps tune power received on STA/UE. -Can test two 4x4 Wi-Fi AP s or a 4x4 Wi-Fi AP with a 2x2 LTE device. Ethernet, HDMI, USB Ports LTE monitor OTA 8 LTE UEs Wi-Fi STAs Wi-Fi sniffer Multi-Path Emulation 8 802.11 AP Wi-Fi Attenuator Ethernet Ethernet Attenuator LTE LTE eNB / Wi-Fi AP Submission Slide 7 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Coexistence Testbed w/o multipath Goals: -Similar to multipath testbed -AP and eNB couple OTA in top box via antennas. Ethernet, HDMI, USB Ports LTE monitor OTA Attenuator Wi-Fi STAs LTE UEs Wi-Fi sniffer 6-8 802.11 AP Wi-Fi 4 Ethernet Ethernet 2-4 LTE LTE eNB Submission Slide 8 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Hidden Node Scenario One possible test scenario is characterizing how Unlicensed-LTE and Wi-Fi handle hidden nodes When group 1,3 cannot directly observe each other or observe below ED levels how will the detection mechanisms work? AP1/enB1 AP2/enB2 AP3/enB3 Clients2 Clients3 Clients1 Hidden Node problem: Groups 1,2 and 2,3 can observe each other. But groups 1,3 cannot (outside of the Rx sensitivity) Submission Slide 9 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Multiple Nodes/Hidden Node Testbed Client Box 2 Client Box 1 Client Box 3 Attenuator Attenuator Attenuator Wi-Fi/LTE Clients Wi-Fi/LTE Clients Wi-Fi/LTE Clients Wi-Fi Wi-Fi Wi-Fi LTE LTE LTE AP/eNB Box 1 AP/eNB Box 2 AP/eNB Box 3 Submission Slide 10 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Hidden Node Configuration Est. Rx Power (dBm) C1 Tx C2 Tx C3 Tx AP1 Tx AP2 Tx AP3 Tx 5Ghz Path Loss Attenuator Client-Client Attenuator AP-Client Cables OTA Loss Tx Power Rx Threshold 6 6 3 C1 Rx - -65 -111 -25 -71 -117 C2 Rx -65 - -65 -71 -25 -71 C3 Rx -111 -65 - -117 -71 -25 AP1 Rx -25 -71 -117 - -77 -123 AP2 Rx -71 -25 -71 -77 - -77 AP3 Rx -117 -71 -25 -123 -77 - 40 +24dBm >-100dBm Clients and AP/eNB in Box 2 see both C1/AP1 and C3/AP3 Devices in 1 and 3 cannot observed each other (outside of the Rx Sensitivity) Link between 1/3 can be added depending on scenario. Submission Slide 11 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Extra Slides Submission Slide 12 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Rack Mount Testing Ideally would like to put in the chamber to maximize isolation, but this may not be an option. Rackmount RF shielding may also be poor, so may consider putting enB in it s own box to reduce leakage. Ethernet, HDMI, USB Ports LTE monitor OTA Attenuator Wi-Fi STAs LTE UEs Wi-Fi sniffer 6 802.11 AP Wi-Fi 4 2 Ethernet Ethernet Option 2: Rack outside of chamber LTE eNB (Rack mounted) 2 Option 1: Rack inside chamber LTE eNB (Rack mounted) Submission Slide 13 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Multiple Small Cell Testbed LTE-U Indoor Simulation Scenarios (SI5-8) -Based on test scenarios provided by 3GPP (See 2) -Chaining chambers expands wireless loading/environment -Multiple AP s, Small Cells operating co-channel 1 2 3 n Length = 120 m 1 n 2 3 Width = 50 m 15 m Links between nodes control interactions 15 m Operator 1 Small Cell Operator 2 Small Cell Private WiFi AP Submission Slide 14 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 Possible Multiple Small Cell/Enterprise loading configuration RF daisy-chain coupling to emulate space among AP/eNB pairs Submission Slide 15 Ben Lampert, octoScope
July 2015 doc.: IEEE 802.19-15/0055r3 References [1] LTE-U Technology and Coexistence, LTE-U Forum May 28th, 2015 http://www.lteuforum.org/uploads/3/5/6/8/3568127/lte- u_coexistence_mechansim_qualcomm_may_28_2015.p df [2] LTE-LAA 3GPP Document 36.889-011 Submission Slide 16 Ben Lampert, octoScope
