Presentation is loading. Please wait.

Presentation is loading. Please wait.

Doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Time-Correlated Packet Errors in MAC Simulations.

Published byArthur Stokes Modified over 8 years ago

Similar presentations

Presentation on theme: "Doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Time-Correlated Packet Errors in MAC Simulations."— Presentation transcript:

1 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Time-Correlated Packet Errors in MAC Simulations Angelo Poloni and StefanoValle STMicroelectronics Gianluca Villa Politecnico di Milano (angelo.poloni@st.com, stefano.valle@st.com, gvilla@elet.polimi.it)

2 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 2 Introduction MAC simulations require time-correlated packet errors in order to emulate PHYs in a realistic way. Simple Markov chains (Good/Bad channel), proposed so far, seem to be a rough approximation of the channel behavior [1]. Information Theory provides the “Channel Capacity” (CC) concept; CC is a suitable metric to predict PHY performances [2]. The “instantaneous” value of the CC can be used to predict the “instantaneous” packet error probability.

3 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 3 Basic idea “Instantaneous” CC at time is a function of the channel transfer function and of the average SNR; The “instantaneous” CC can be considered a stochastic process. It can be proved experimentally that, once the PHY is defined, the instantaneous PER is a function of CC If PER versus CC is available from link-level simulations (e.g. as a Look-Up-Table[LUT]), it is sufficient to generate the stochastic process that represents the CC versus time in the MAC simulator. Its instantaneous value can be used to read the PER LUT.

4 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 4 CC for frequency selective SISO channel Assumption: channel flat in each OFDM sub- carrier (SC) bandwidth Capacity on k-th OFDM sub-carrier is given by CC can be considered as the sum of the Capacities on each SC

5 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 5 Simulation conditions u 802.11a standard u Rate 6 Mbps u Channel model “B” (as defined by 802.11n standard) u E s /N 0 = 8 dB Instantaneous PER versus instantaneous CC Erroneous packets are in correspondence of low CC

6 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 6 PER versus CC 802.11a Rate 6 Mbps Channel model “B” (802.11n standard) E s /N 0 [0:4:20] dB

7 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 7 CC stochastic process In order to simulate the CC stochastic process in MAC simulators it is necessary to have its statistical characterization. This is done in the next two slides. After that an approach to reproduce such process in a MAC simulator is proposed.

8 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 8 Characterization of CC: pdf Channel model “B” (802.11n standard)

9 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 9 Characterization of CC: mean and standard deviation 8101214161820 10 20 30 40 50 60 70 80 90 100 110 Es/N 0 Capacity [Mbps] mean std

10 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 10 Generation of CC stochastic process Emulate the stochastic process with a Birth-Death Markov process [3] Pros : –easy to implement; –low loading of MAC simulator. Cons : –Relative high number of LUTs. 0 Mbps5 Mbps# Mbps …

11 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 11 Characterization of Markov chain 1/2 Transition probabilities are given by the following matrix (4 state Markov chain is assumed for simplicity) Matrix can be estimated form a discrete version of the CC versus time curve.

12 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 12 Characterization of Markov chain 2/2 Only contiguous states transitions are allowed Contiguous states are uniformly spaced; capacity step is  C. The assumption of transitions towards contiguous states only is not obvious. In order to guarantee that such assumption is correct, it is necessary that Markov chain time clock (  t) is sufficiently small. A conservative condition is obtained through the following considerations: –Assume the capacity process to be a sinusoid with frequency f D (Doppler Spread); –The condition for having a capacity step less than  C in a time step  t is

13 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 13 Example of Markov chain characterization 1/2   C = 15 Mbps   t = 1 ms  Channel: IEEE B  SNR = 0,4,8,12,16,20,24 dB  Transition probabilities for each SNR are plotted in the next slide

14 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 14 020406080100120140160180200 10 -0.07 10 -0.04 10 -0.01 capacity [Mbps]  i i 020406080100120140160180200 10 -3 10 -2 10 capacity [Mbps]  i,i-1 020406080100120140160180200 10 -4 10 -2 10 0 capacity [Mbps]  i,i+1 SNR = 0 4 8 12 16 20 24 Example of Markov chain characterization 2/2  i,i  i,i-1  i,i+1

15 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 15 Markov chain in MAC simulator Channel Capacity Emulation (Markov Chain) Erroneous Packet Rando m draw Packet OK Mean SNR Shadowing Propagation Law LUT: Markov chain transition probabilities LUT: PER vs SNR vs CC Distanc e

16 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 16 Erroneous packet event: drawing methods Random draw methods: –draw for erroneous packet event every new packet (Method 1); –draw for erroneous packet event every new capacity state (Method 2).

17 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 17 Preliminary Model validation Validation metrics are: –average PER; –Average Burst Error Length (ABEL); –Standard Deviation of Burst Error Length (STDBEL).

18 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 18 Validation results 1/3   C = 15 Mbps   t = 1 ms  Channel: IEEE B  Random draw: method 1

19 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 19   C = 15 Mbps   t = 1 ms  Channel: IEEE B  Random draw: method 2 Validation results 2/3 PER ABEL STDBEL SNR

20 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 20 Validation results 3/3 PER ABEL STDBEL 8101214161820 10 -4 10 -2 10 0 8 1214161820 0 5 10 15 8101214161820 0 10 20 30 SNR PHY behavior Markov model PHY behavior Markov model PHY behavior Markov model   C = 2 Mbps   t = 1 ms  Channel: IEEE B  Random draw: method 2

21 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 21 Comments on model validation PER matches the PHY behavior. Matching ABEL and STDBEL is the most critical aspect: –in the special case here presented, promising results have been obtained by shortening the Capacity Step of the Markov Chain and by using the Draw method number 2; –a general rule for calibrating the Capacity Step is still unknown.

22 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 22 Summary of the simulation method Link level simulator PER versus SNR CC Channel only simulator (SNR, channel model) CC versus TIME versus SNR CC MARKOV CHAIN (transition probabilities) Statistical analysis MAC simulator N.B., Channel only simulator, Link level simulator and MAC simulator run separately

23 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 23 Some comments Channel state is condensed in a single number (CC versus time): overloading of MAC simulators is avoided. CC versus time can be easily reproduced by other parties and thus it can be easily standardized. PHY behaviors (PER versus time) can be easily included and updated with LUTs (PER versus CC). A method for including the effects of interferers will be investigated in the near future. The same approach is applicable to MIMO channels and PHYs.

24 doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 24 References 1.J. M. McDougall, “Low Complexity Channel Models for Approximating Flat Rayleigh Fading in Network Simulations”, PhD Dissertation, Texas A&M University, August 2003. 2.IST- FITNESS D4.3, “Simulation Platform Structure and System Level Performance Evaluation” (http://www.telecom.ntua.gr/fitness/ ) 3.Hong Shen Wang, Moayeri, N., “Finite-state Markov Channel-a Useful Model for Radio Communication Channels”, IEEE Transactions on Vehicular Technology, Feb. 1995 Volume 44 Number 1.

Download ppt "Doc.: IEEE 802.11-04-0064-00-000n Submission January 2004 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Time-Correlated Packet Errors in MAC Simulations."

Similar presentations

PHY Abstraction for TGax System Level Simulations

PHY Abstraction for TGax System Level Simulations
Doc.: IEEE 802.11-04/0015r2 Submission January 2004 Yang-Seok Choi et al., ViVATOSlide 1 Comments on Ergodic and Outage Capacity Yang-Seok Choi,

Doc.: IEEE /0015r2 Submission January 2004 Yang-Seok Choi et al., ViVATOSlide 1 Comments on Ergodic and Outage Capacity Yang-Seok Choi,
Doc.: IEEE 802.19-04/0018r0 Submission May 2004 Steve Shellhammer, Intel CorporationSlide 1 IEEE 802.19 Wireless Coexistence TAG Steve Shellhammer

Doc.: IEEE /0018r0 Submission May 2004 Steve Shellhammer, Intel CorporationSlide 1 IEEE Wireless Coexistence TAG Steve Shellhammer
Channel Estimation for Mobile OFDM

Channel Estimation for Mobile OFDM
Doc.: IEEE 802.11-03/0682-00-000k Submission September 2003 Brian Johnson, Nortel Networks 802.11a Performance Over Various Channels 9 September 2003 Presenter:

Doc.: IEEE / k Submission September 2003 Brian Johnson, Nortel Networks a Performance Over Various Channels 9 September 2003 Presenter:
Doc.: IEEE 802.11-11/0436r0 Submission February 2011 Mediatek Path Loss and Delay Spread Models for 11ah Date: 2011-03-14 Authors: Slide 1.

Doc.: IEEE /0436r0 Submission February 2011 Mediatek Path Loss and Delay Spread Models for 11ah Date: Authors: Slide 1.
Doc.: IEEE 802.11-03/839r1 Submission November 2003 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Bell-Spike Power Doppler Spectrum Model Angelo Poloni.

Doc.: IEEE /839r1 Submission November 2003 A. Poloni, S. Valle, STMicroelectronicsSlide 1 Bell-Spike Power Doppler Spectrum Model Angelo Poloni.
Submission May, 2000 Doc: IEEE802.11-00 / 086 Steven Gray, Nokia Slide Brief Overview of Information Theory and Channel Coding Steven D. Gray 1.

Submission May, 2000 Doc: IEEE / 086 Steven Gray, Nokia Slide Brief Overview of Information Theory and Channel Coding Steven D. Gray 1.
Kuang-Hao Liu et al Presented by Xin Che 11/18/09.

Kuang-Hao Liu et al Presented by Xin Che 11/18/09.
Doc.: IEEE 802.11-15/568r0 Submission Frequency Selective Scheduling (FSS) for TGax OFDMA May 2015 Slide 1 Date: 2015-05-11 Authors: Kome Oteri (InterDigital)

Doc.: IEEE /568r0 Submission Frequency Selective Scheduling (FSS) for TGax OFDMA May 2015 Slide 1 Date: Authors: Kome Oteri (InterDigital)
Dynamic Tuning of the IEEE 802.11 Protocol to Achieve a Theoretical Throughput Limit Frederico Calì, Marco Conti, and Enrico Gregori IEEE/ACM TRANSACTIONS.

Dynamic Tuning of the IEEE Protocol to Achieve a Theoretical Throughput Limit Frederico Calì, Marco Conti, and Enrico Gregori IEEE/ACM TRANSACTIONS.
Modeling OFDM Radio Channel Sachin Adlakha EE206A Spring 2001.

Modeling OFDM Radio Channel Sachin Adlakha EE206A Spring 2001.
Simulation.

Simulation.
Doc.: IEEE 802.11-14/1227r3 SubmissionSlide 1 OFDMA Performance Analysis Date: 2014-09-15 Authors: Tianyu Wu etc. MediaTek Sept 2014 NameAffiliationsAddressPhoneEmail.

Doc.: IEEE /1227r3 SubmissionSlide 1 OFDMA Performance Analysis Date: Authors: Tianyu Wu etc. MediaTek Sept 2014 NameAffiliationsAddressPhone .
Doc.:IEEE 802.11-15/0206r0 Submission January 2015 Shiwen He, Haiming Wang Pilot Design for OFDM PHY for 802.11aj(45 GHz) Authors/contributors: Date: 2015-1-21.

Doc.:IEEE /0206r0 Submission January 2015 Shiwen He, Haiming Wang Pilot Design for OFDM PHY for aj(45 GHz) Authors/contributors: Date:
Submission doc.: IEEE 11-14/0803r1 July 2014 Wookbong Lee, LG ElectronicsSlide 1 Packet Length for Box 0 Calibration Date: 2014-07-14 Authors:

Submission doc.: IEEE 11-14/0803r1 July 2014 Wookbong Lee, LG ElectronicsSlide 1 Packet Length for Box 0 Calibration Date: Authors:
Submission doc.: IEEE 802.11-14/1452r0 November 2014 Leif Wilhelmsson, EricssonSlide 1 Frequency selective scheduling in OFDMA Date: 2014-11-03 Authors:

Submission doc.: IEEE /1452r0 November 2014 Leif Wilhelmsson, EricssonSlide 1 Frequency selective scheduling in OFDMA Date: Authors:
Doc.: IEEE 802.11-14/0053r0 Submission Jan. 2014 Zhang Jiayin (Huawei Technologies)Slide 1 Further Considerations on Calibration of System Level Simulation.

Doc.: IEEE /0053r0 Submission Jan Zhang Jiayin (Huawei Technologies)Slide 1 Further Considerations on Calibration of System Level Simulation.
ECE 480 Wireless Systems Lecture 14 Problem Session 26 Apr 2006.

ECE 480 Wireless Systems Lecture 14 Problem Session 26 Apr 2006.
Doc.: IEEE 802.11-13/1391r0 Submission Nov. 2013 Yakun Sun, et. Al.Slide 1 About SINR conversion for PHY Abstraction Date: 2013-11-11 Authors:

Doc.: IEEE /1391r0 Submission Nov Yakun Sun, et. Al.Slide 1 About SINR conversion for PHY Abstraction Date: Authors:

Similar presentations

Ads by Google