Submission doc.: IEEE 802.11-12/0329r1 March 2012 Chittabrata Ghosh, Nokia Slide 1 Date: 2012-03-12...
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Submission doc.: IEEE 802.11- 12/0329r1 March 2012 Chittabrata Ghosh, Nokia Slide 1 Date: 2012-03-12 Authors: Group Synchronized DCF N am e A ffiliations A ddress Phone em ail Chittabrata G hosh Nokia 2054 U niversity Ave, Suite 600 Berkeley, CA 94703 +1650200756 6 [email protected] om K lausD oppler Nokia +1510423245 8 [email protected] Taejoon K im Nokia [email protected] Zhong-YiJin Nokia +1650284613 8 [email protected]
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Transcript of Submission doc.: IEEE 802.11-12/0329r1 March 2012 Chittabrata Ghosh, Nokia Slide 1 Date: 2012-03-12...
Submission
doc.: IEEE 802.11-12/0329r1March 2012
Chittabrata Ghosh, NokiaSlide 1
Date: 2012-03-12
Name Affiliations Address Phone email Chittabrata Ghosh
Nokia 2054 University Ave, Suite 600 Berkeley, CA 94703
+16502007566
Klaus Doppler Nokia +15104232458
Taejoon Kim Nokia [email protected]
Zhong-Yi Jin Nokia +16502846138
Authors:
Group Synchronized DCF
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Abstract
• STAs with a group may be allowed to contend for the medium – idea of group synchronized DCF (GS-DCF)
• Medium access window allowed to certain groups and prohibited to other groups
- AP decides on defining the medium access start and end times
• Performance comparison of GS-DCF with DCF
Slide 2
March 2012
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Group Medium Access in Beacon Frame
Slide 3
March 2012
• AP informed of Supported Rates, QoS Capability, QoS Traffic Capability, and Power Capability in Association Request frame from STAs
• AP clusters STAs into groups and informs the group IDs in Association Response frame
• Beacon frame defines the medium access time for each group
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Proposed Information Element
Slide 4
March 2012
• Propose to add an Information Element termed as Group Access Parameter Set (GAPS) element in the Beacon frame
• GAPS element for group ‘n’ shall comprise of:
(i) GID: Group Identification
(ii) Group Access Start Time: Value of T_n
(iii) Group Interval End Time: End time of medium access
Beacon Interval
Time Stamp
Capability Information
SSIDSupported Rates
FHParameter Set
DSParameter Set
CFParameter Set
TIM GrPSParameter Set
Proposed IEBeacon Frame
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Medium Access of STA Groups
Slide 5
March 2012
• Group i’s medium access Start Time is decided by the AP
• Start Time based on number of associated / active STAs per group and priority setting per group
• Group Interval End Time for i-th group is identical to prohibition time for (i+1)-th group
Group 1 Interval Group 2 Interval Group 3 Interval Group 4 Interval Group 5 Interval
T_1 = 0 T_2 T_3 T_4 T_5 T_6
Group Access Start Time for Group 3
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Overlapping Medium Access Times among STA Groups
Slide 6
March 2012
• Overlapping medium access times for efficient medium contention, e.g., Groups 4 and 3 medium access
• Overlapping medium access reduced idle medium time
Group 5 IntervalGroup 2 Interval Group 1 Interval
Group 4 Interval
Group 3 Interval
T_5 = 0 T_2 T_1 T_4 T_3 T_5
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
GS-DCF Medium Access
Slide 7
March 2012
• Beacon frame consists of information on all group synchronized medium access periods until next beacon
• Time not assigned to groups is assigned for regular DCF
Group 5 Interval Group 2 Interval Group 1 Interval Group 4 Interval Group 3 Interval
0 T_5 T_2 T_1 T_4 T_3
Beacon Short Beacon
GAPS
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Simulation Parameters
Slide 8
March 2012
GS-DCF Mechanism ParametersNumber of groups: 5
Group size: 20 STAs
Packet accumulation interval 0-800ms
Group active interval 800-1000ms
Data rate per STA: 5 - 35 kbps
No RTS/CTS
DCF ParametersNumber of STAs: 100 STAs
Active interval 0-1000ms
Data rate per STA: 5 - 35 kbps
No RTS/CTS
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Simulation Parameters
Slide 9
March 2012
Channel Bandwidth 2MHz
TX Power 30dBm
Antenna Gains 3dB
Communication Range 100 Meters
Packet Size 250Bytes
Slot Time/SIFS/DIFS 48µs/160µs/256µs
(CWmin, CWmax) (15, 1023)
MCS BPSK ½
Simulation time 16s
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Throughput Comparison between DCF and GS-DCF
Slide 10
March 2012
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Summary
• GAPS element proposed to be included in the Beacon frame
• Only limited number of groups are allowed to contend during specified medium access window defined in the GAPS element
• GS-DCF outperforms DCF with increasing number of STAs contending for the channel
Slide 11
March 2012
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
References
1. “Power Saving Possibilities for Networks Supporting a Large number of STAs,” doc.: IEEE 802.11-12/0028r1, January 2012, Renesas Mobile Corporation
2. “DCF Enhancements for Large Number of STAs,” doc.: IEEE 802.11-11/1255r0, September 2011, CATR
Slide 12
March 2012
Submission
doc.: IEEE 802.11-12/0329r1
Chittabrata Ghosh, Nokia
Straw Poll
Do you agree to include the GAPS information element in the Beacon frame?
Slide 13
March 2012
