doc.: IEEE 802.11-13/1081r0

Submission Sayantan Choudhury

HEW Simulation Methodology

Date: Sep 16, 2013Authors:

Name Company Address Phone email Sayantan Choudhury Nokia 2075 Allston Way, Berkeley,

CA +1 510 599 9268 Sayantan.choudhury@nokia.com

Jarkko Kneckt Jarkko.kneckt@nokia.com Klaus Doppler Olli Alanen Esa Tuomaala Chittabrata Ghosh Mika Kasslin Prabodh Varshney Scott Marin Nokia Solutions

and Networks 131 Skyline Drive, Murphy, Texas

+1-469-363-1694

scott.marin@nsn.com

Slide 1

doc.: IEEE 802.11-13/1081r0

Submission

Abstract

• Propose to identify a few well-defined scenarios that can be simulated by multiple companies

• HEW simulations can easily get quite overwhelming. The goodness of the HEW enhancements should be visible in both simple and complicated scenarios.

• Simple scenarios may help to educate how simulators and enhancements operate

September 2013

Sayantan ChoudhurySlide 2

doc.: IEEE 802.11-13/1081r0

Submission

How to get started?

• It has been quite awhile since last simulation results were published...– 802.11n has the last publicly available simulations from 2005

• To ensure simulator operation correctness, the known simulation cases could be run with known PHY and MAC (802.11n and 802.11ac)– This could be fast way of getting all the simulators to the same

page

– 802.11n and 802.11ac radios may have poor performance in HEW scenarios, better to compare these radios in suitable scenarios

– This is good starting point for HEW simulator and then extend to dense deployment scenarios

Sayantan ChoudhurySlide 3

doc.: IEEE 802.11-13/1081r0

Submission

Overview of HEW Simulation Scenarios

• The HEW simulation scenarios should be examples to prove that HEW performance criteria can be fulfilled• They enable benchmarking of the proposed enhancements in dense

deployments

• HEW simulation scenarios should be simple enough and focus on what is essentially required to improve performance– Complicated data generation and network layer operations should be

avoided

• HEW scenarios should provide default simulation parameters to enable easy cooperation between different companies

Sayantan ChoudhurySlide 4

doc.: IEEE 802.11-13/1081r0

Submission

EXAMPLE SIMULATION CASE

Sayantan ChoudhurySlide 5

doc.: IEEE 802.11-13/1081r0

Submission

Recap, Dense Apartment Building Scenario• Multi-floor building

– Important scenario in many countries. Fiber to the home offers >>1Gbps backhaul capacity

– 10 floors, 3 m height in each floor– 2x10 rooms in each floor– Room size:10m x 10m x 3m

• AP locations (assuming 50 APs):– Place 50 APs in the randomly selected rooms at xy-

location (uniform distribution) at 1.5m above floor level

– At maximum one AP per room

• STA locations, 5 STA/AP (=250 STAs):

– In each room that has an AP, place five STAs in random xy-locations (uniform distribution) at 1.5m above the floor level

– Each of the five STAs in a room is associate to the AP in the room

Sayantan ChoudhurySlide 6

doc.: IEEE 802.11-13/1081r0

Submission

Recap, Dense apartment building simulation parameters

• Environment: Apartment building

– 10 floors, 20 rooms per floor 10mx10mx3m

• AP location: 50 (max 1 per room randomly placed)

• Channel model: Indoor

• Wall/Floor Penetration loss: 5/10/20 dB (@5 Ghz),

4 dB between floors

• Transmit power

– Max AP : 23 dBm

– Max STA TxP: 19 dBm

• BW: 11ac/80 MHz (same primary channel)

• Antenna configuration

– AP/STA: 2/2

• Antenna gain

– 0dBi Omni antenna pattern

• Link Adaptation

– Enabled: SNR based

• EDCA parameters

– Default (AC_VI)

– TxOP: 2 msSayantan Choudhury

• RTS/CTS

– Option 1: Off

– Option 2: On

• Aggregation

– MPDU: 64

– MSDU: 2

• Max retries: 4

• Block Acknowledgement

– Enabled

• Constant Bit Rate traffic of DL or UL traffic

– DL or UL traffic is randomly assigned to a STA

– 80% of STA with 50Mbps DL traffic

– 20% of STA with 50Mbps UL traffic

– Packet size 1500B

• Number of iterations: 10

• Simulation Duration: 2 secs

Slide 7

doc.: IEEE 802.11-13/1081r0

Submission

User throughput CDF

Downlink Uplink

Changing one or two parameters gives very different results.

Sayantan Choudhury8

doc.: IEEE 802.11-13/1081r0

Submission

Observations

• Simple scenarios where only 1 or 2 parameters are varied can often provide good insight into system performance

• Higher wall penetration loss results in reduced interference, hence improving throughput

• RTS/CTS helps protect ongoing transmission and reduces collisions resulting in improved uplink performance

• Better mechanisms to deal with increased interference in extremely dense deployment scenarios is needed

Sayantan ChoudhurySlide 9

doc.: IEEE 802.11-13/1081r0

Submission

Summary• Benefitting from simulations requires:

• Well defined scenarios and parameters

• Understanding how features and enhancements operate

• Analysis of the reasons for good or poor performance

• Starting from simple simulations may be more useful in understanding the main performance bottlenecks of existing design and benefits of proposed enhancements

• Need to identify 1 or 2 baseline 11n/ac/HEW scenarios (e.g. residential and enterprise) with default parameters and simplified traffic profiles that can be simulated by multiple companies

Sayantan ChoudhurySlide 10