1. 6 July, 2009
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: FPP SUN Simulation Results – Redpine Signals
Date Submitted: 6 July, 2009
Source: Partha Murali Company: Redpine Signals Inc.
Address: 2107 N First Street, Suite #680, San Jose, USA
Voice: ,
Re: IEEE Task Group 4g Call for Proposals (CFP) on 22 January, 2009
Abstract: This presentation summarizes the performance results of the “Future-Proof” OFDM PHY Merged proposal for Option-2 and Option-3
Purpose: Simulation Results demonstrating the performance of the Merged OFDM proposal for g PHY
Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P
Partha Murali, Redpine Signals Inc.

2. Future Proof Platform for SUN: Simulation Results – Redpine Signals
6 July, 2009
Future Proof Platform for SUN:
Simulation Results – Redpine Signals
Partha Murali
IEEE 802 Plenary Session
San Francisco
July 2009
Contributors: Rishi Mohindra [MAXIM], Emmanuel Monerie [Landis & Gyr], Steve Shearer [Independent], Shusaku Shimada [Yokogawa Electric Co.], Bob Fishette [Trilliant], Sangsung Choi, [ETRI], Roberto Aiello [Independent], Kendall Smith [Aclara], David Howard [On-Ramp]
Partha Murali, Redpine Signals Inc.

3. Outline Future Proof OFDM PHY overview of modes simulated
6 July, 2009
Outline
Future Proof OFDM PHY overview of modes simulated
Tx Model for Scalable OFDM PHY
Channel Model Used
Simulation Results - AWGN
Simulation Results - Multipath
Sensitivity and Link Margin Calculations
Summary
References
Partha Murali, Redpine Signals Inc.

4. Future-Proof OFDM PHY – Modes simulated are highlighted
6 July, 2009
Future-Proof OFDM PHY –
Modes simulated are highlighted
OFDM Option 1
OFDM Option 2
OFDM Option 3
OFDM Option 4
OFDM Option 5
Unit
FFT size
128 64 32 16 8
Active Tones
108 52 26 14 6
# Pilots tones 4 2
# Data Tones
100 48 22 12
Approximate Signal BW
1064
518
264
146 68
kHz
BPSK 1/2 rate coded and 4x repetition 98
kbps
BPSK 1/2 rate coded and 2x repetition
195 94 43
BPSK 1/2 rate coded
391
187 86 47
BPSK 3/4 rate coded
586
281
129 70
QPSK 1/2 rate coded
781
375
172
QPSK 3/4 rate coded
562
258
141
16-QAM 1/2 rate coded
750
344 62
16-QAM 3/4 rate coded
516
For details on the proposed OFDM-PHY please refer to
g-FPP-SUN-Detailed-Proposal.doc
Partha Murali, Redpine Signals Inc.

5. Tx Model for Scalable OFDM PHY
6 July, 2009
Tx Model for Scalable OFDM PHY
Partha Murali, Redpine Signals Inc.

6. Multipath Channel Model used
6 July, 2009
Multipath Channel Model used
SUN Multipath Channels
Channel Type
Tap Number
Tap Relative Delay (us)
Channel Sampling Rate (KHz)
Tap Sample Number
Average relative power (dB)
Typical Urban 1
3125
amp1 2 5 16
-22.3
amp2
Bad Urban -3
Hilly Terrain 15 47
-8.6
Partha Murali, Redpine Signals Inc.

7. Multipath Channel Matlab Code (for Reference)
6 July, 2009
Multipath Channel Matlab Code (for Reference)
function [y]=two_ray_multipath_channel(x,amp1,amp2,n_FsDelay)
% x is the input to the Multipath channel
% y is the output of the Multipath channel
%amp1 = Average amplitude of 1'st path in dB
%amp2 = Average amplitude of 2'nd path in dB
%n_FsDelay = Delay in Number of Samples at the sampling rate of x.
% If x is sampled at 3125KHz (5x) and n_FsDelay=16 then sample delay of second tap is 5us.
RV1=(randn(1,1)+j*randn(1,1))/sqrt(2)*10^(amp1/20);
RV2=(randn(1,1)+j*randn(1,1))/sqrt(2)*10^(amp2/20);
y=(x*RV1 + [zeros(1,n_FsDelay) x(1:(length(x)-n_FsDelay))]*RV2)/sqrt(10^(amp1/20) + 10^(amp2/20));
Partha Murali, Redpine Signals Inc.

8. 6 July, 2009
Notes on Simulation
Channel Models used are from: ETSI EN v3.2.1 which are chosen for SUN simulations
Channel was Sampled at 5x sampling rate of signal (625Khz * 5 = 3125Khz)
The Multipath Fading channel output should “not” be normalized for each packet. The Multipath Fading channel has “unit-normalized” gain in the “ensemble” sense over multiple packets.
All PER plots are with respect to Ensemble SNR (dB) = Tx Signal Power – Path-Loss – 20*log10(k*T*B).
SNR at Receiver input was varied by varying the Path Loss
500 channel realizations were simulated for each Path loss (each SNR point) to estimate the PER at that SNR
Partha Murali, Redpine Signals Inc.

9. Approximate Signal Bandwidth
6 July, 2009
Simulation Results: AWGN – Summary
Future Proof OFDM Proposal Option-2
Sampling Rate
Approximate Signal Bandwidth
In-Band Thermal Noise Floor k*T*B (dBm) assuming 625KHz Noise bandwidth
FFT Points
Modulation
Code Rate
Data-Rate (Kbps)
AWGN 10Byte (dB)
AWGN 100Byte (dB)
AWGN 1KByte (dB)
625KHz
518KHz
-116 64
16-QAM
1/2
750 8
9.5
10.5
QPSK
3/4
562.5
5.5
6.5
7.4
375 3
4.1
4.9
BPSK
187.5
1.5
1.8
Notes 1
Receiver Used had an implementation loss of <0.5dB 2
The numbers in green are the SNRs for 1% Packet Error Rate
Partha Murali, Redpine Signals Inc.

10. Simulation Results: AWGN – Summary
6 July, 2009
Simulation Results: AWGN – Summary
Future Proof OFDM Proposal Option-3
Sampling Rate
Approximate Signal Bandwidth
In-Band Thermal Noise Floor k*T*B (dBm) assuming 312.5KHz Noise BW
FFT Points
Modulation
Code Rate
Data-Rate (Kbps)
AWGN 10Byte (dB)
AWGN 100Byte (dB)
AWGN 1KByte (dB)
312.5KHz
264KHz
-119 32
16-QAM
3/4
516
11.6
13.3
14.2
1/2
344
7.9
9.3
10.2
QPSK
258
5.5
6.3
7.1
172
2.9 4
4.7
BPSK 86
1.4
1.5
1.8
Notes 1
Receiver Used had an implementation loss of <0.5dB 2
The numbers in green are the SNRs for 1% Packet Error Rate
Partha Murali, Redpine Signals Inc.

11. 6 July, 2009
Partha Murali, Redpine Signals Inc.

12. Simulation Results: Multipath – Summary
6 July, 2009
Simulation Results: Multipath – Summary
Sampling Rate
Approximate Signal Bandwidth
In-Band Thermal Noise Floor k*T*B (dBm) assuming 625KHz Noise BW
FFT Points
Modulation
Code Rate
Data-Rate (Kbps)
Typical Urban 100 Byte (dB)
Bad Urban 100 Byte (dB)
Hilly Terrain 100 Byte (dB)
625KHz
518KHz
-116 64
16-QAM
1/2
750 19
18.6 18
QPSK
3/4
562.5
16.4
17.5
375 13 9
10.4
BPSK
187.5
8.5 7 8
Notes 1
Receiver Used had an implementation loss of <0.5dB 2
The numbers in green are the SNRs for 10% Packet Error Rate
Partha Murali, Redpine Signals Inc.

13. 6 July, 2009
Partha Murali, Redpine Signals Inc.

14. Sensitivity and Link Budget Calculations (Bandwidth Option-2)
6 July, 2009
Sensitivity and Link Budget Calculations (Bandwidth Option-2)
Mode
Option-2 1KByte, BPSK ½,
187.5Kbps
Option-2 1KByte, 16-QAM ½,
750Kbps
Transmit Power (example)
30dBm
Transmit & Receive Antenna Gains (combined)
0dBi
Fading Channel Model
No Fading (AWGN)
Bad Urban Fading
Required Rx SNR
1.8 7
18.6
In-band Noise Floor k*T*B (dBm)
-116
RF Transceiver Noise Figure (including RF Front-end) (dB) 4
Digital Implementation Loss (dB) 1
Receive Sensitivity at Antenna for 187.5Kbps Mode (dBm)
-109.2
-104
-92.4
“REAL” Link Margin (dB)
139.2
134
122.4
Partha Murali, Redpine Signals Inc.

15. Summary, Conclusions and Discussion
6 July, 2009
“Multipath Fade Margin” Reduces Considerably with BICM (Bit-Interleaved Coded Modulation) OFDM Systems
The difference in performance between AWGN and Fading results is about 7dB for Option-2
Dummy repeater nodes would be minimal in most deployments (even sub-urban & rural) => easy to approach 100% regional coverage for AMI & Smart-grid
Excess link-margin can be traded OFF for lesser Tx Power (simpler PA => low-cost, low-power)
Future-Proof OFDM provides scalable bandwidth Options
Fits all regulatory domains – 1x, 2x, 4x, 8x and 16x bandwidth options
Bandwidth options 2 and 3 are simulated in this document
Future-Proof OFDM provides scalable data-rates in each bandwidth option
94-750Kbps for Option-2 (>15dB range in SNR of operation)
43-516Kbps for Option-3 (>20dB range in SNR of operation)
All the above is achieved in a coherent fashion with a simple symbol structure to enable single chipset implementations for multiple bandwidth options
Partha Murali, Redpine Signals Inc.

16. 6 July, 2009
THANK YOU
Partha Murali, Redpine Signals Inc.