1. Enhancement on resource utilization in OBSS environment
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Enhancement on resource utilization in OBSS environment
Date:
Authors:
Name
Affiliations
Address
Phone
Giwon Park
LG Electronics
19, Yangjea-daero 11gil, Seocho-gu, Seoul , Korea
Jeongki Kim
Suhwook Kim
Kiseon Ryu
HanGyu Cho
Giwon Park, LG Electronics
John Doe, Some Company

2. Month Year
doc.: IEEE yy/xxxxr0
September 2013
Abstract
Main goal of HEW is to increase spectrum efficiency and area throughput [1].
This presentation introduces efficiency enhancement by resource utilization in OBSS environment.
Slide 2
Giwon Park, LG Electronics
John Doe, Some Company

3. Problem Statement: Legacy NAV Protection
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Problem Statement: Legacy NAV Protection
NAV protection does not allow AP2 to transmit data to the STA2 when AP 2 receiving RTS first and receiving either CTS or the following data.
Slide 3
Giwon Park, LG Electronics
John Doe, Some Company

4. Problem Statement: Legacy NAV Protection
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Problem Statement: Legacy NAV Protection
AP2 is allowed to reset NAV and transmit data when receiving RTS first but receiving neither CTS nor the following data (refer to IEEE section )
Slide 4
Giwon Park, LG Electronics
John Doe, Some Company

5. Consideration on enhancement
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Consideration on enhancement
Legacy NAV protection overkills efficiency
Always when receiving RTS, NAV does not allow transmission
No consideration on topologies and scenarios
Question:
“In which topologies and scenarios, NAV protection can be relaxed to enhance efficiency?”
Slide 5
Giwon Park, LG Electronics
John Doe, Some Company

6. Classification on possible cases
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Classification on possible cases
Scenarios
BSS1 holds a TXOP first, and BSS2 is to reuse the TXOP
BSS2 should not make an impact on the BSS1 hold a TXOP first.
Four Cases
Based on four possible topologies
BSS 1
BSS 2
Case I DL UL
Case II
Case III
Case IV
Slide 6
Giwon Park, LG Electronics
John Doe, Some Company

7. Case I: BSS1 DL / BSS2 UL Un-manageable hidden node problem to BSS1
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Case I: BSS1 DL / BSS2 UL
Un-manageable hidden node problem to BSS1
CTS of AP2 collides with STA1’s receiving data.
Slide 7
Giwon Park, LG Electronics
John Doe, Some Company

8. Case II: BSS1 DL / BSS2 DL Un-manageable hidden node problem to BSS1
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Case II: BSS1 DL / BSS2 DL
Un-manageable hidden node problem to BSS1
RTS of AP2 collides with STA1’s receiving data.
Slide 8
Giwon Park, LG Electronics
John Doe, Some Company

9. Case III: BSS1 UL / BSS2 UL Tolerable interference from BSS1
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Case III: BSS1 UL / BSS2 UL
Tolerable interference from BSS1
BSS2 can reuse TXOP of BSS1 if AP2 receives STA2 RTS
Slide 9
Giwon Park, LG Electronics
John Doe, Some Company

10. Case IV: BSS1 UL / BSS2 DL Tolerable interference from BSS1
Month Year
doc.: IEEE yy/xxxxr0
September 2013
Case IV: BSS1 UL / BSS2 DL
Tolerable interference from BSS1
BSS2 can reuse TXOP of BSS1 if AP2 receives STA2 CTS
Slide 10
Giwon Park, LG Electronics
John Doe, Some Company

11. Month Year
doc.: IEEE yy/xxxxr0
September 2013
Conclusion
This contribution studied on resource utilization in OBSS environment.
Following enhancement points were observed:
one BSS can not reuse TXOP of the other BSS if one yields unmanageable interference to the other (Cases I, II).
one BSS can reuse TXOP of the other BSS if one can endure interference from the other (Cases III, IV).
A possible approach to enhance efficiency
If BSS overhears RTS, not CTS, BSS is allowed to reuse resource
Need to study about detailed procedures and conditions.
Slide 11
Giwon Park, LG Electronics
John Doe, Some Company

12. September 2013
References
[1] wng-high-efficiency-wlan-straw-poll [2] IEEE P REVmcTM/D1.5, June 2013 [3] s-on-hidden-and-exposed-terminal-problems
Giwon Park, LG Electronics