May 2014
Doc: IEEE 802.15-14-0245-00-0008
Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [Proposal Outline of Completely Distributed Power Control Mechanism for Peer-Aware
Communications ]
Date Submitted: [May 2nd, 2014]
Source: [David Smith †, Nicole Sawyer †, Siyu Zhou †, Marco Hernandez, Huan-Bang Li, Igor Dotlić, Ryu
Miura]
Company: [NICTA† Australia, NICT Japan]
Address: [Tower A, 7 London Circuit, Canberra ACT 2601, Australia]
Voice:[+61 2 62676200] Fax: [+61 2 62676220] E-Mail:[[email protected]]
Re: [In response to call for technical contributions to TG8]
Abstract: [ ]
Purpose: [Material for discussion in 802.15.8 TG]
Notice: This document has been prepared to assist the IEEE P802.15. 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 P802.15.
†NICTA is funded by the Australian Government through the Department of Communications and the Australian Research Council
through the ICT Centre of Excellence Program.
Submission
Slide 1
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Introduction
• Completely distributed transmit power control, including
prioritized communications (at PHY layer), for any
number of Tx/Rx, source/destination pairs (single-hop) or
source/relays/destination pairs (multi-hop).
• This is based on research work by David Smith, Nicole
Sawyer and Siyu Zhou, NICTA Australia, and presented as
a joint proposal with NICT Japan to TG8.
• Accompanying specification for this mechanism is given in
DCN-???
Submission
Slide 2
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Introduction
• The power control mechanism is a refinement of
distributed discrete SINR balancing, by incorporating
game-theoretic utility maximization, in order to obtain
Pareto optimal outcomes.
• It rapidly converges to acceptable packet delivery ratio
(PDR) for high priority communications, faster than
conventional power control techniques
• Moreover, the proposal reduces power consumption across
all sources, significantly, compared to conventional power
control techniques
Submission
Slide 3
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Packet Delivery Ratio (PDR) – Modeling
• PDR=1−PER , where PER=Packet Error Rate.
• The PDR, Pd, can be accurately modeled with a two-parameter
compressed exponential function [Smith2013] of inverse signalto-interference-plus-noise ratio as:
  1
Pd  exp   
  ac





– where γ = SINR, ac and bc are constant parameters that depend of the
modulation and coding scheme.
– The above expression is restated in the following equivalent form, with
two parameters, for later analysis :
 
Pd  exp a b
Submission



bc
bc
1
, where a     and b  bc
 ac 
Slide 4
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Packet Delivery Ratio (PDR) – Modeling
• Assuming interference as aggregate Gaussian noise, the
metric Es/N0 described in the TGD and contribution DCN
13-169r1 can be expressed as
 Tsym 
Es
  SINR |dB 4.77 dB
 SINR |dB 10 log 
N0
T
 s 
–where Tsym is symbol time and Ts is sampling time.
–Hence, SINR=Es/N0−4.77 dB = γ
– For convolutional code rate and modulation type, table on next page
Submission
Slide 5
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Packet Delivery Ratio (PDR) – Modeling
Table 1
Modulation and Coding Rate
BPSK rate 1/2
BPSK rate 3/4
QPSK rate 1/2
QPSK rate 3/4
16-QAM rate 1/2
16-QAM rate 3/4
64-QAM rate 2/3
64-QAM rate 3/4
64-QAM rate 5/6
•
•
bc
8.85
9.48
9.02
9.29
8.31
8.45
8.34
7.81
8.034
Please note the parameters ac and bc are for 150 packet size.
For any packet size Mp, the PDR is given by
– where
Submission
ac
3.891
2.13
1.95
1.066
0.62
0.275
0.125
0.085
0.06
 
Pd  exp a  b
Mp  1 
 
a 
150  ac 
bc
and b   bc
Slide 6
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Packet Delivery Ratio (PDR) – Modeling
1
0.9
0.8
PDR = (1-PER)
0.7
0.6
0.5
0.4
BPSK(1/2) - PDR approx.
BPSK(1/2) - PDR [Park2013]
QPSK(3/4) - PDR approx.
QPSK (3/4) - PDR [Park2013]
16QAM (3/4) - PDR approx.
16QAM (3/4) - PDR [Park2013]
0.3
0.2
0.1
0
-10
-5
0
5
10
SINR = E s /N0 - 4.77 (dB)
15
20
Pd compared with curves, 3 examples from DCN 13-169r1, shows
a very good approximation (across all 9 fits from Table 1,
root-mean-square error ≤ 0.0021)
Submission
Slide 7
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Distributed Power Control - Scenario
• Single hop with N source-destination pairs
– All non-paired sources act as hidden terminals (e.g., non-coordinated at MAC
layer in terms of scheduling, undiscovered etc.)
– Aim to minimize Tx power and obtain target PDR (equivalently target SINR)
– Prioritized communications at PHY level, i.e., priority levels low, medium,
high can implement three different target PDRs for any source/destination pair.
Submission
Slide 8
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Distributed Power Control - Scenario
• Multi-hop
s1
r1,1
r1,m
d1
s2
r2
r2,m
d2
s3
r3
r3,m
d3
– Completely decentralized, no coordination of interfering pairs.
– Prioritized communications at PHY level, i.e., priority levels low,
medium, high can implement three different target PDRs for any
source/destination pair.
– This scenario is feasible for proposed power control if decodeand-forward (or alternatively detect-and-forward) communications
is implemented.
Submission
Slide 9
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control Mechanism
• Assume any Tx power from a discrete available transmit
power levels vector:
– Pvec ϵ (0, 1W] for the 2.4 GHz and 5.7 GHz bands
– Pvec ϵ (0, 1mW] band A,D, (0, 20 mW] band B, (0, 250 mW] band C
of sub-1GHz band for Japan.
• Assume power control finitely repeated for T stages in
contiguous frames.
– In order to ensure Pareto optimality (Tx power is minimized and
target PDR is at least reached).
Submission
Slide 10
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control Algorithm - Initialization
• At time t = 0; In the initiation of the mechanism: according to communications
priority obtain target PDR, typical values are pdt,i =0.99 (high), or 0.95 (medium) or
0.9 (low).
• Then compute equivalent target SINR, γt,i, (also for Decode-and-Forward, Dec-F, and
Detect-and-Forward, Det-F, cg coding gain)
𝛾𝑡,𝑖,𝐷𝑒𝑐−𝐹 = 𝛾𝑡,𝑖,
ln 𝑝𝑑𝑡,𝑖
=
𝑎
1
𝑏
𝛾𝑡,𝑖,𝐷𝑒𝑡−𝐹,𝑚∈{1,2 = 10
𝑐𝑔
10
ln 𝑝𝑑𝑡,𝑖
𝑎
1
𝑏
• Initial transmission powers for any source node i, t = 0, Pt,i(0), can be chosen
randomly from possible Pvec values, or alternately suitably according to priorities of
communications.
∀𝑖 At t = 0;
Set flagi= 0.
Submission
Slide 11
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control Algorithm (cont.) - Inputs
•
∀𝑖 From time t = 0,…,T-1,
 i t  
PS ,i t 
Pi , Noise Interference t 
2
ℎ𝑖,𝑖
𝜏 =
 vec 
𝑃𝑆,𝑖 𝜏
𝑃𝑡,𝑖 (τ)
where in estimate denominator of received interference + noise power;
Pi , Noise Interference t  and received target signal power PS ,i t 
using common methods for SINR estimation (references in DCN??)
where 𝑃𝑡,𝑖 τ is the known transmit power of node i.
;
Pvec hi2,i t 
Pi ,NoiseInterference t 

PD  exp aγ bvec

t = t+1;
Submission
Slide 12
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control (cont.) 1st step –with conditions
if t ≥ 3  γi(τ-1)≈ γi(τ-2)  Pi(τ-1)= Pi(τ-2)  flagi = 1,
flagi = 2;
elseif t ≥ 2  γi(τ-1)≈ γi(τ-2)  Pi(τ-1)= Pi(τ-2)  flagi = 0,
flagi = 1;
end if
If flagi = 0,
 t ,i


Pi (t )est.  max Pvec 
Pi (t  1)
 i (t  1)


else,
;
 t ,i


Pi (t )est.  min Pvec 
Pi (t  1)
 i (t  1)


end if
;
ki ,est .  arg indexPvec  Pi (t ) est . 
Pvec
Submission
 e,i  γ vec (ki ,est. )
Slide 13
and
Pe,i  Pvec ( ki ,est. )
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control 2nd step –Refinement Basis
• According to non-cooperative repeated game with
imperfect information (as PDs act concurrently), a unique
Nash equilibrium is obtained by maximizing for link i:
U i ( Pi (t ))   Pi (t )  d i (t ) ( pd ( Pi ) ) i
– where Ui() is an utility function, di() is a weighting factor, pd (Pi(τ))
is a PDR value as function of Pi(τ) for stage τ, νi=3.
Submission
Slide 14
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Power Control (cont.) 2nd step –Refinement
• The powers Pt,i(τ) for each link i at stage τ is computed as
d iest 
Pe,i

 pdt ,i a b 
b
e ,i
where ν=3.

Ui  Pvec  diest PD
ki  arg index maxU i 
Ui
.
Pt ,i (t )  Pvec (k i )
(A vector of length L of possible utilities ∀i)
(Find the unique Nash equilibrium point for PD i)
Transmit Pt,i(t) from PD i at time slot t ;
End Algorithm at T = t, when flagi = 2, ∀i.
Submission
Slide 15
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation Set-Up
• Considering an square area of 500mx500m, transmitters/sources dropped
randomly with uniform distribution, unicast transmissions
– Paired receivers/destinations dropped with uniform distribution (single-hop)
– Paired relays+destinations dropped with uniform distribution (two-hop)
– Consider N source/destination (or source/relay/destination) pairs from these, which
act as hidden terminals to each other – undiscovered at MAC (or PHY)
• Same for two-hop as single-hop
• Model from DCN 12-459r7 Sec 2.2.6 “Path loss between terminals located
below roof-top for 900 MHz and 2.4 GHz bands” with
– Frequency =2.4 GHz, p=50% and Lurban=6.8 dB
•
Maximum transmit power 20 dBm (Minimum 0-dBm, but effective for lower limits also.)
– Antenna gains are 0 dBi.
– Receivers noise figure 7 dB; implementation losses and fade margin 8 dB
– Discrete power level spacing of 2 dB, with a total of 11 discrete power levels
• Both Static Fading and Slow Rayleigh fading considered
– Slow fading, fading parameter fDTs = 0.002, fD Doppler spread, Ts power sampling period,
generated using Jakes model
Submission
Slide 16
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-1 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation
– Packet size Mp = 512 bytes
– Single-hop with repeated power control mechanism applied on 1000
occasions, with T=40 stages in each occasion.
– Static Fading
– N = 20 links or source/destination pairs with distances chosen at
random with uniform distribution in [10m, 30m].
– N(N−1) interfering links distances having a minimum of 2.5 m and an
average of 270m for interfering source/s to target destination
– AWGN noise variance between 10-10 to 10-11 mW
– Comparison with decentralized SINR balancing, using first-step, with
modification in this outline to completely decentralize that of
[Andersin1998]
Submission
Slide 17
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-1 Results
18
1
Source/s needing most Tx power - propos.
Source/s needing most Tx power - only bal`ing
Sources mean Tx power - propos.
Sources mean Tx power - only bal`ing
16
0.98
High priority target PDR
Packet Delivery Ratio (PDR)
14
Power (dBm)
12
10
8
6
0.96
0.94
Medium priority target PDR
0.92
High priority - propos.
High priority - bal`ing
Medium priority - propos.
Medium priority - bal`ing
Low priority - propos.
Low priority - bal`ing
4
0.9
2
0
0
5
10
15
20
25
Time slots (stages), t
30
35
40
0.88
0
5
Low priority target PDR
10
15
20
25
Time slots (stages), t
30
35
40
Power Saving of 22.2 dBm over the N = 20 links
Submission
Slide 18
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-2 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation
– Packet size Mp = 512 bytes
– Single-hop with repeated power control mechanism applied on 1000
occasions, with T=120 stages in each occasion.
– Slow Rayleigh Fading, fDTs = 0.002
– N = 20 links or source/destination pairs with distances chosen at
random with uniform distribution in [10m, 30m].
– N(N−1) interfering links distances having a minimum of 1.5 m and an
average of 270m for interfering source/s to target destination
– AWGN noise variance between 10-10 and 10-11 mW
– Comparison with decentralized SINR balancing, using first-step, with
modification in this outline to completely decentralize that of
[Andersin1998]
Submission
Slide 19
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-2 Results
1
18
16
0.98
Packet Delivery Ratio (PDR)
14
Power (dBm)
12
10
Source/s needing most Tx power - propos.
Source/s needing most Tx power - only bal`ing
Sources mean Tx power - propos.
Sources mean Tx power - only bal`ing
8
6
High priority target PDR
0.96
0.94
Medium priority target PDR
0.92
High priority - propos.
High priority - bal`ing
Medium priority - propos.
Medium priority - bal`ing
Low priority - propos.
Low priority - bal`ing
4
0.9
2
0
0
20
40
60
80
Time slots (stages), t
100
120
0.88
0
20
Low priority target PDR
40
60
80
Time slots (stages), t
100
120
Power Saving of 32.1 dBm
Submission
Slide 20
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-3 Results
• Further Simulation parameters:
– ¾ coding rate with QPSK modulation
– Packet size Mp = 64 bytes
– Two-hop, Decode-and-Forward with repeated power control mechanism applied
on 1000 occasions, with T=40 stages in each occasion.
– Static Fading
– N = 20 links or 20 source/relay/destinations with each hop distance chosen at
random with uniform distribution in [10m, 25m], thus total source/destination
distance uniformly distributed in [20,50m].
– N(N−1) interfering links distances having a minimum of 1.9 m and an average of
271m for interfering sources to target relays, and interfering relays to target
destinations
– AWGN noise variance between 10-10 to 10-11 mW
– Comparison with decentralized SINR balancing, using first-step, with
modification from this outline to completely decentralize that of [Andersin1998]
Submission
Slide 21
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-3 Results
20
1
Source(or Relay)/s needing most Tx power - propos.
Source(or Relay)/s needing most Tx power - only bal`ing
Sources/Relays mean Tx power - propos.
Sources/Relays mean Tx power - only bal`ing
18
0.98
Packet Delivery Ratio (PDR)
16
Power (dBm)
14
12
10
8
6
High priority target PDR
0.96
0.94
Medium priority target PDR
0.92
0.9
0.88
Low priority target PDR
4
0.86
2
0
0
5
10
15
20
25
Time slots (stages), t
30
35
40
High priority - propos.
High priority - bal`ing
Medium priority - propos.
Medium priority - bal`ing
Low priority - propos.
Low priority - bal`ing
0.84
0
5
10
15
20
25
Time slots (stages), t
30
35
40
Power Saving of 23.4 dBm
Submission
Slide 22
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-4 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation
– Packet size Mp = 64 bytes
– Two-hop, Decode-and-Forward, with repeated power control mechanism
applied on 1000 occasions, with T=120 stages in each occasion.
– Slow Rayleigh Fading, fDTs = 0.002
– N = 20 links or 20 source/relay/destinations with each hop distance chosen at
random with uniform distribution in [10m, 25m], thus total source/destination
distance uniformly distributed in [20,50m].
– N(N−1) interfering links distances having a minimum of 1.6 m and an
average of 270m for interfering sources to target relays, and interfering relays
to target destinations AWGN noise variance between 10-10 and 10-11 mW
– Comparison with decentralized SINR balancing, using first-step, with
modification in this outline to completely decentralize that of
[Andersin1998]
Submission
Slide 23
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-4 Results
18
1
16
Power (dBm)
12
10
Source(or Relay)/s needing most Tx power - propos.
Source(or Relay)/s needing most Tx power - only bal`ing
Sources/Relays mean Tx power - propos.
Sources/Relays mean Tx power - only bal`ing
8
6
Packet Delivery Ratio (PDR)
14
High priority target PDR
0.95
Medium priority target PDR
0.9
4
Low priority target PDR
2
0
0
20
40
60
80
Time slots (stages), t
100
120
0.85
0
20
40
High priority - propos.
High priority - bal`ing
Medium priority - propos.
Medium priority - bal`ing
Low priority - propos.
Low priority - bal`ing
60
80
Time slots (stages), t
100
120
Power Saving of 34 dBm
Submission
Slide 24
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-5 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation, Packet size Mp = 512 bytes
– Two-hop, Decode-and-Forward, compared with single hop with repeated
power control mechanism applied on 1000 occasions, with T=40 stages
– Static fading
– N = 20 links or 20 source/relay/destinations with each hop distance chosen at
random with uniform distribution in [10m, 25m], thus single-hop
source/destination distance uniformly distributed in [20,50m].
– N(N−1) interfering links distances having a minimum of 1.9 m and an
average of 270m for interfering sources to target relays, and interfering relays
to target destinations, multi-hop, 0.31m and 273m for interfering sources to
target destinations single-hop
– AWGN noise variance between 10-10 and 10-11 mW
Submission
Slide
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-5 Results
18
1
16
0.9
Packet Delivery Ratio (PDR)
14
Power (dBm)
12
10
8
Source(or Relay)/s needing most Tx power - DecF
Sources needing most Tx power - Single-Hop
Sources/Relays mean Tx power - DecF
Sources mean Tx power - Single-Hop
6
4
Medium priority target PDR
0.8
Low priority target PDR
0.7
0.6
High priority - DecF
High priority - SingleHop
Medium priority - DecF
Medium priority - SingleHop
Low priority - DecF
Low priority - SingleHop
0.5
2
0
High priority target PDR
0
5
Submission
10
15
20
25
Time slots (stages), t
30
35
40
0.4
Slide 26
0
5
10
15
20
25
Time slots (stages), t
30
35
40
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-6 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation, Packet size Mp = 512 bytes
– Two-hop, Decode-and-Forward, compared with two-hop detect and forward
with repeated power control mechanism applied on 1000 occasions, with
T=40 stages
– Static fading
– N = 20 links or 20 source/relay/destinations with each hop distance chosen at
random with uniform distribution in [10m, 25m], thus total source/destination
distance uniformly distributed in [20,50m].
– N(N−1) interfering links distances having a minimum of 3.4 m and an
average of 270m for interfering sources to target relays, and interfering relays
to target destinations, multi-hop
– AWGN noise variance between 10-10 and 10-11 mW
Submission
Slide
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-6 Results
20
1
18
Source(or Relay)/s needing most Tx power - DetF
Source(or Relay)/s needing most Tx power - DecF
Sources/Relays mean Tx power - DetF
Sources/Relays mean Tx power - DecF
Power (dBm)
14
High priority target PDR
Packet Delivery Ratio (PDR)
16
12
10
8
6
0.95
Medium priority target PDR
0.9
4
Low priority target PDR
2
0
0
5
10
15
20
25
Time slots (stages), t
30
35
40
0.85
0
5
10
15
20
25
Time slots (stages), t
High priority - DetF
High priority - DecF
Medium priority - DetF
Medium priority - DecF
Low priority - DetF
Low priority - DecF
30
35
40
Tx Power Saving of 38.5 dBm of Decode-and-Forward hop
over Detect-and-Forward hop
Submission
Slide 28
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-7 Results
• Further Simulation parameters:
– ¾ coding rate with BPSK modulation, Packet size Mp = 512 bytes
– Two-hop, Decode-and-Forward, compared with two-hop detect and forward
with repeated power control mechanism applied on 1000 occasions, with
T=120 stages
– Slow Rayleigh fading, fDTs = 0.002
– N = 20 links or 20 source/relay/destinations with each hop distance chosen at
random with uniform distribution in [10m, 25m], thus total source/destination
distance uniformly distributed in [20,50m].
– N(N−1) interfering links distances having a minimum of 4.8 m and an
average of 272m for interfering sources to target relays, and interfering relays
to target destinations, multi-hop
– AWGN noise variance between 10-10 and 10-11 mW
Submission
Slide
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Simulation-7 Results
1
20
18
14
High priority target PDR
Packet Delivery Ratio (PDR)
16
Power (dBm)
0.98
Source(or Relay)/s needing most Tx power - DetF
Source(or Relay)/s needing most Tx power - DecF
Sources/Relays mean Tx power - DetF
Sources/Relays mean Tx power - DecF
12
10
8
6
0.96
0.94
Medium priority target PDR
0.92
0.9
0.88
High priority - DetF
High priority - DecF
Medium priority - DetF
Medium priority - DecF
Low priority - DetF
Low priority - DecF
Low priority target PDR
4
0.86
2
0
0.84
0
20
40
60
80
Time slots (stages), t
100
120
0
20
40
60
80
Time slots (stages), t
100
120
Tx Power Saving of 43.4 dBm of Decode-and-Forward hop
over Detect-and-Forward hop over N = 20 links
Submission
Slide 30
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Conclusions
– Relatively simple (and very effective) Tx power control
mechanism that does not rely on channel prediction.
– Significant Tx power savings. From 22 dBm to 34 dBm.
– Prioritized communications enabled at PHY: important in disaster
response (high priority communications reaching target PDR, in
less time stages than simply using SINR balancing).
Submission
Slide 31
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
Conclusions
– Power control enabled by simple, accurate PDR model based on
the TGD and contribution DCN 13-169r1.
– The proposed power control method shown to be applicable in
slow fading channels, where direct channel gains vary between
stages of power control.
– Also, the proposed power control can be applied asynchronously
as all sources (relays) do not need to transmit concurrently
– Simulations based on single-hop communications, and multi-hop
communication with decode-and-forward or detect-and-forward
• All schemes viable with the power control mechanism here
• Decode-and-Forward significantly more efficient needing much lower output
Tx power than Detect-and-Forward
Submission
Slide 32
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)
May 2014
Doc: IEEE 802.15-14-0245-00-0008
References
– [Smith2013] Smith, D.; Portmann, M.; Tan, W.; Tushar, W.,
"Multi Source-Destination Distributed Wireless Networks: ParetoEfficient Dynamic Power Control Game with Rapid
Convergence," IEEE Transactions on Vehicular Technology,
December 2013. [Available online under subscription]
Google: doi 10.1109/TVT.2013.2294019
– [Andersin1998] Andersin, Michael, Zvi Rosberg, and Jens
Zander. "Distributed discrete power control in cellular PCS."
Wireless Personal Communications 6.3 (1998), pp. 211-231.
Submission
Slide 33
Smith, Sawyer, Zhou (NICTA),
Hernandez,Li,Dotlić,Miura (NICT)