doc.: IEEE 11-14/0112r1
Mar. 2014
Wi-Fi interference measurements
in Korea (Part II)
Date: 2014-03-17
Authors:
Name
Affiliations Address
Phone
email
Minho Cheong
NEWRACOM
193 Moonjiro,
Yuseong-Gu, Daejeon,
Korea
+82-42-860-5635
[email protected]
Hyoung Jin Kwon
NEWRACOM
193 Moonjiro,
Yuseong-Gu, Daejeon,
Korea
+82-42-860-1698
[email protected]
Jae Seung Lee
ETRI
Submission
[email protected]
Slide 1
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
Abstract
• This presentation gives set of additional measurement
results of Wi-Fi interferences in Seoul metropolitan
area, especially depending on the deployment density of
Wi-Fi devices, which will be helpful for problem setting
of HEW.
Submission
Slide 2
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
Additional Path-loss due to
Human Body Blockage [1]
• In super-dense scenarios, in addition to general indoor (from
802.11n/ac channel model) or outdoor (from WINNER or ITU
model), we need to consider the following environments as well
AP
My STA
(smart phone)
Submission
Slide 3
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
Measurement Campaign
• Measurement schedule & Measurement spot
– Seoul Express Bus Terminal (indoor) in Seoul in January 2014
• Equipment
– AirMagent Wi-Fi Analyzer Pro, Mobile AP, Jperf 2.0.2 Server
• Measurement done on 2.4GHz (channel 9) by 802.11g
– Measured DL PHY data rate from Laptop to mobile AP
– Measured & analyzed DL MAC packets from Laptop to mobile AP
Laptop
Jperf server (wired)
Mobile AP
Submission
Slide 4
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
Measurement Campaign (2)
• Limitations on Measurements
– So many moving people at all times
– Not able to measure for a long time
– because mobile AP used cannot hold large traffics
• “AirMagnet Wi-Fi Analyzer”
– can gather all the Wi-Fi data
– Overall or per specific SSID or MAC address
– can analyze all the statistics of Wi-Fi signals
Submission
Slide 5
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
PHY Measurement results of DL traffic
• Measured DL packets from mobile AP to Laptop
– Distance between them is 10m (in the middle of many people)
Laptop
Jperf server (wired)
Mobile AP
• 3 conditions tried per population density
– all the other conditions same
– 0.05 people/m2 (very few), 0.25 people/m2(some people), 0.5 people/1m2 (crowded)
Average Rate
Submission
0.05 people/m2
0.25 people/m2
0.5 people/m2
PHY rate (Mbps)
15.045
6.281
1.391
# of packets/sec.
1496.18
1384.01
296.25
Slide 6
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
MAC Measurement results of DL traffic
• 3 conditions tried per population density
– all the other conditions same
– 0.05 people/m2 (very few), 0.25 people/m2(some people), 0.5 people/1m2 (crowded)
Packet types
0.05 people/m2
0.25 people/m2
0.5 people/m2
Control frame, ACK
36 %
57 %
63 %
Probe req./response
4%
6%
8%
Data frame
55 %
31 %
23 %
Beacon & others
5%
6%
6%
Retry rate
Retry rate
0.05 people/m2
11 %
0.25 people/m2
12 %
0.5 people/m2
24 %
– The higher population density, the more controls & the less data frames
– In addition, retry rate is highly sensitive due to different level of contentions
Submission
Slide 7
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
Conclusions
• Measurements and analysis are done on dense Wi-Fi
environments according to different level of population
density
• As population density goes high, performance of Wi-Fi
goes extremely degraded
– Due to much more contentions with devices near by
– Due to additional path loss by human-body blockage for my signal
• Solutions to dense Wi-Fi environments are strongly
required so that we could also manage to use Wi-Fi in
the future (explosion of number of Wi-Fi devices)
Submission
Slide 8
Minho Cheong (NEWRACOM)
doc.: IEEE 11-14/0112r1
Mar. 2014
References
• [1] 11-13-1113-00-0hew-channel-modeling-for-denseWi-Fi-environments
Submission
Slide 9
Minho Cheong (NEWRACOM)