The document discusses energy efficient techniques for cellular base stations based on Malaysia's solar radiation characteristics. It introduces the problem of increasing energy consumption from the growing number of base stations and underutilized stations. Various cooperation management techniques are classified that aim to reduce energy usage based on traffic load, including base station switching on and off when traffic is low while maintaining coverage through active remaining stations. Studies on this technique have shown potential energy savings of up to 50%.

1.
Ir.
Dr.
Rosdiadee
Nordin
Faculty
of
Engineering
and
Built
Environment
Universi<
Kebangsaan
Malaysia
Energy
Efficient
Cellular
Base
Sta3ons
based
on
the
Characteris3cs
of
Malaysia’s
Solar
Radia3on
Exposure
:
adee@ukm.edu.my
:
hDps://sites.google.com/site/rosdiadee/
:
hDp://my.linkedin.com/pub/rosdiadee-­‐nordin

2. Outline
q
Introduc<on
and
Problem
Background
q
Classifica<ons
of
Energy-­‐Saving
Techniques
q
Case
Study:
Feasibility
Study
of
Green
Wireless
Network
for
Malaysia
q
Future
Direc<ons
&
Challenges
Related
to
Green
Wireless

3. IoT
50
Billion
Video
demand
69%
Mobile
Subscribers
9.5
Billion
-­‐
1,000
2,000
3,000
4,000
5,000
6,000
7,000
2005
2006
2007
2008
2009
2010
2011
2012
2013
Mobile-­‐cellular
subscrip3ons
in
(Million)
Introduc3on
Big
Success
of
Mobile
Communica<ons

4.
Number
of
subscribers
increased
Mobile
data
traffic
increased
Base
sta3ons
will
be
increased
Z.
J.
Wu,
Y.
Zhang,
M.
Zukerman,
and
E.
Yung
(2015).
Energy-­‐Efficient
Base
Sta3ons
Sleep
Mode
Techniques
in
Green
Cellular
Networks:
A
Survey.
IEEE
Communica,ons
Surveys
&
Tutorials
.
Cont’d
Growth
in
Mobile
Base
Sta<ons
With
5G,
the
number
of
BSs
globally
will
grows
to
reach
approximately
8
million
by
2020.

5. In
Malaysia,
Mobile
cellular
subscrip<ons
reached
more
than
42.9
million
in
2014

6. Cont’d
57%
20%
15%
6%
2%
Base
sta<on
Mobile
switching
Core
network
Data
center
Retail
E.
Oh,
B.
Krishnamachari,
X.
Liu,
and
Z.
Niu
(2011).
Towards
Dynamic
Energy-­‐Efficient
Opera3on
of
Cellular
Network
Infrastructure.
IEEE
Commun.
Mag.
Ø BSs
are
densely
deployed
and
overlapping
Ø
80%
of
the
BSs
are
quite
lightly
loaded
for
80%
of
the
<me,
but
s<ll
waste
energy
Reducing
the
power
consump3on
of
BSs
is
the
key!

7. Ø All
BSs
are
ON
(ac<ve)
all
the
<me
(to
keep
coverage),
although
traffic
is
almost
zero
in
many
areas.
Ø Each
BS
almost
transmits
in
peak
power,
although
peak
traffic
only
lasts
for
a
very
short
<me
in
most
cells
Cont’d
Why
so
many
BSs
under-­‐u3lized?
Migrate
to
Green
Communica3ons
Ø From
World-­‐Wide-­‐Web
to
World-­‐
Wide-­‐Wireless
Ø Definitely
should
not
be
World-­‐
Wide-­‐Wait
and
World-­‐Wide-­‐Waste!
Exis3ng
cellular
is
neither
smart
nor
green

8. Ø
The
traffic
loads
during
the
day<me
differs
from
those
during
the
night
for
both
of
the
business
and
residen<al
areas.
Cont’d
Traffic
dynamics
can
provide
opportuni3es
for
energy
saving
Ø Key
challenge:
How
to
guarantee
the
coverage
and
radio
service?
Why
lightly-­‐loaded
BSs
can’t
be
switched
off
(sleep)?

9. Green
Wireless
Cellular
Techniques
Coopera3on
Management
Coopera<ve
base
sta<ons
BSs
switching
On/Off
Cell
zooming
HetNet
Coopera<ve
mobile
operators
Operator
switching
On/Off
Hardware
Solu3ons
Improvements
PA
Renewable
energy
sources
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2014).
Classifica3on,
Recent
Advances
and
Research
Challenges
in
Energy
Efficient
Cellular
Networks.
Wireless
Personal
Communica,ons,
77
(2),
1249-­‐1269.
Classifica*ons of Energy-­‐Saving Techniques

10. Ø
BSs
Switch
Off/On
Idea
Switching
off
a
specific
number
of
BSs
during
low-­‐traffic,
while
guaranteeing
coverage
and
services
by
the
ac<ve
remaining
BSs
Savings
25-­‐50%
Advantages
Easier
and
less
costly
for
tes<ng
&
implementa<on
Shortcomings
Coverage
issue
and
UE
baDery
life.
Coopera3on
Management
Techniques
The
philosophy
behind
all
the
proposed
methods
is
the
same:
reduce
energy
consump<on
based
on
the
traffic
load.
Cont’d
The
first
research
discussed
this
technique:
L.
Chiaraviglio,
D.
Ciullo,
M.
Meo,
M.
A.
Marsan
(2008).
Energy-­‐Aware
UMTS
Access
Networks.
Proc.
in
the11th
Interna,onal
Symposium
on
Wireless
Personal
Mul,media
Communica,ons
(WPMC’08),

11. 37.5%
50.0%
17.0%
40.7%
30.0%
30.0%
40.0%
35.0%
29.0%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
Chiaraviglio
et
al.,
2008,
(Residen<al)
Chiaraviglio
et
al.,
2008,
(Office)
Chiaraviglio
et
al.,
2008,
(Hierarchical)
Chiaraviglio
et
al.,
2009,
(Uniform)
Chiaraviglio
et
al.,
2009,
(Hierarchical)
Marsan
et
al.,
2009
Xiang
et
al.,
2011
Lorincz
et
al.,
2012
Bousia
et
al.,
2012
BSs
Switch
Off/On
Cont’d
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2014).
Classifica3on,
Recent
Advances
and
Research
Challenges
in
Energy
Efficient
Cellular
Networks.
Wireless
Personal
Communica,ons,
77
(2),
1249-­‐1269.
Summary
of
Switch-­‐Off
Previous
Studies
that
have
Inves<gated
the
Possibility
of
Energy
Savings

12. Ø
Cell
Zooming
Idea
When
conges<on
occurs
in
a
cell,
the
congested
cell
could
“zoom-­‐in,”
while
neighboring
cells
with
a
smaller
amount
of
traffic
could
“zoom-­‐out”
to
provide
coverage
for
the
UEs.
Savings
Up
to
40%.
Advantages
Large
savings.
Shortcomings
Coverage
issue,
Interference,
and
Compa<bility.
Cont’d
The
first
research
discussed
this
technique:
Z.
Niu,
Y.
Wu,
J.
Gong,
and
Z.
Yang
(2010).
Cell
Zooming
for
Cost-­‐Efficient
Green
Cellular
Networks.
IEEE
Communica<ons
Magazine.
Cell
zooming
opera3ons
in
cellular
networks:
(a) Original
size;
(b) Central
cell
zooms
in
when
load
increases;
(c) Central
cell
zooms
out
when
load
decreases

13. Ø
HetNet
Idea
Macrocells
are
deployed
to
provide
overall
coverage,
while
small
cells
(e.g.,
micro,
pico,
femto)
are
ac<vated
if
the
demand
increases.
Savings
Up
to
70%
Advantages
Largest
reported
savings.
Shortcomings
Interference,
Resource
Management,
and
Complexity.
Cont’d
The
first
research
discussed
this
technique:
H.
Claussen,
L.
T.
W.
HO,
F.
Pivit
(2008).
Effects
of
joint
macrocell
and
residen3al
picocell
deployment.
Proc.
in
the
19th
Annual
IEEE
Interna<onal
Symposium
on
Personal,
Indoor
and
Mobile
Radio
Communica<ons
(PIMRC'08)
E-UTRAN
Macro
Cell A
E-UTRAN
Pico/Micro
Cell B
Ø Two
E-­‐UTRAN
cells
(Cell
A,
Cell
B)
with
separate
frequency
bands
cover
the
same
geographical
area.
Ø Cell
B
has
a
smaller
size
(Pico
Cell
or
Micro
Cell)
than
Cell
A
(Macro
Cell)
and
is
covered
totally
by
Cell
A
Ø
Cell
A
is
deployed
to
provide
con<nuous
coverage
of
the
area,
while
Cell
B
increases
the
capacity
of
the
special
sub-­‐areas,
such
as
hot
spots.
Ø Cell
B
deac<va<on
in
case
that
light
traffic.
Cell
B
ac<va<on
when
the
traffic
resumes
to
a
high
level.

14. Ø
Coopera3ve
Mobile
Operators
Idea
Switch
off
one
or
more
BSs
when
the
traffic
load
is
low,
managing
coverage
with
a
subset
of
remaining
ac<ve
BSs
through
either
the
same
operator
network
or
another
operator,
with
both
networks
covering
the
same
geographical
area.
Savings
Depends
on
the
number
of
operators.
Advantages
A
good
exploita<on
of
the
network.
Shortcomings
Complexity
&
compa<bility,
resource
management,
QoS
&
human
factor(?)
Cont’d
The
first
research
discussed
this
technique:
M.
A.
Marsan,
M.
Meo
(2010).
Energy
efficient
wireless
Internet
access
with
coopera3ve
cellular
networks.
Computer
Networks.

15. Renewable
Energy
System
Cont’d
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2016).
Green
wireless
network
op3misa3on
strategies
within
smart
grid
environments
for
Long
Term
Evolu3on
(LTE)
cellular
networks
in
Malaysia.
Renewable
Energy,
85,
157-­‐170.

16. The
concept
of
using
diesel
generator
(DG)
to
power
rural
BS
has
become
much
less
viable
for
the
mobile
operators
for
the
following
reasons:
• Fuel,
opera<ng,
and
maintenance
costs.
• Environmental
impacts:
air
pollu<on,
emitng
harmful
components
such
as
CO2,
SO2.
• Technical
issues:
The
efficiency
of
the
system
is
low
(30%)
Net
costs
of
opera<ng
a
diesel
generator
51%
20%
15%
14%
Mobile
Sector
Fixed
Narrowband
Telecom
Devices
Fixed
Broadband
51%
of
the
ICT
industry!
Forecast
Carbon
Footprint
Contribu<on
by
Telecom
for
2020.
Total=
179
MtCO2
Mo3va3ons
Towards
Renewable
Energy
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2015).
Energy
Op3miza3on
of
Hybrid
Off-­‐Grid
System
for
Remote
Telecommunica3on
Base
Sta3on
Deployment
in
Malaysia.
EURASIP
Journal
on
Wireless
Communica,ons
and
Networking,
2015:64.

17. Burkina
Faso
Kenya
Angola
Arab
gulf
region
Lebanon
Nepal
India
Bangladesh
Turkey
Sri
Lanka
…
and
…
Malaysia!
Brazil
Italy
Prac*cal Solar Powered Base Sta*on
Implementa*on

18. Solar
power
system
in
remote
areas
of
Burkina
Faso
Provided
by
ZTE,
2009
hDp://wwwen.zte.com.cn/endata/magazine/ztetechnologies/2009year/no7/ar<cles/200907/t20090710_173704.html
Reference:
Requirements:
power
system
is
required
to
provide
power
for
BTS
and
microwave
equipment;
the
total
power
consump<on
is
550W.
System
Design:
1.
Photovoltaic
module:
30
pieces
of
165W
monocrystalline
cells;
2.
BaDery:
Two
groups
of
2V/1000Ah
Gel
OPzV;
3.
Charge
controller:
48V/150A
controller.
In
this
project,
22
solar-­‐powered
BTSs
are
deployed.
They
have
a
rela<vely
small
capacity,
which
is
in
the
range
of
400-­‐900W.
Solar
power
system
makes
diesel
re-­‐fuelling
and
maintenance
work
unnecessary,
which
can
save
about
US$150,000
for
operator
every
year.

19. Loca3on:
Solar
powered
base
sta<on
at
the
Italian
city
of
L'Aquila
implemented
by
Ericsson
and
Telecom
Italia.
System
Design:
The
Eco
Smart
solu<on
features
an
ellip<cal
support
structure
coated
with
flexible
solar
panels
‘wrapping’
the
tower
structure.
1. Solar
PV
Panels.
2. BaDeries
3. Solar
charge
controllers
4. DC
power
rec<fiers
Italy,
2009
Reference:
hDp://www.cellular-­‐news.com/story/Operators/38446.php

20. Solar
base
sta3ons
by
Alfa
mobile
operator
in
Lebanon,
2013
Loca3on:
five
remotes
sites,
namely
in
Hourata,
Challita,
Aakoura,
Ouyoun
Laqlouq,
and
Mehmarch,
which
are
implemented
by
ECOsys
company
that
specialist
in
solar
energy
solu<on.
System
Design:
1. Solar
PV
Panels
from
Kyocera.
2. BaDeries
from
EnerSys
3. Solar
charge
controllers
from
Steca,
controlling
the
en<re
energy
flow
while
ensuring
op<mal
baDery
maintenance.
4. DC
power
rec<fiers
from
Eaton,
designed
for
high
power
density
and
opera<ng
efficiency.
Reference:
hDp://www.itgholding.com/news/1899

21. Arab
gulf
region,
2015
Loca3on:
300
solar-­‐powered
base
sta<ons
has
deployed
in
Arab
gulf
region
implemented
by
Eltek.
In
addi<on,
200
sites
will
be
deployed
in
2015
and
2016.
System
Design:
1. PV
panels
(Photovoltaic
Panels),
strong
and
resistant
PV
moun<ngs
2. BaDeries
3. Solar
controllers
&
rec<fiers
The
solu<on
design
is
based
on
full
reliability
on
solar
and
backup
baDeries,
knowing
that
on
few
sites,
unstable
u<lity
and
generators
are
available
for
addi<onal
backup.
The
baDery
autonomy
is
very
high
and
the
solu<on
can
provide
con<nuous
energy
for
5
days.
It
is
worth
men<oning,
Eltek
has
provided
solar
powered
telecom
installa<ons
across
the
African
con<nent,
in
countries
such
as
Angola,
Chad,
Kenya,
Lesotho,
Mauritania,
Morocco,
Mozambique,
Somalia,
Somaliland,
South
Africa,
Zambia
and
Zimbabwe.
Reference:
hDp://www.eltek.com/detail.epl?cat=28971&id=2183193

22. hDp://wwwen.zte.com.cn/endata/magazine/ztetechnologies/2009year/no7/ar<cles/200907/t20090710_173704.html
hDp://www.ztebrasil.com.br/pub/en/press_center/news/201101/t20110105_199217.html
hDp://wwwen.zte.com.cn/endata/magazine/ztetechnologies/2004year/no8/ar<cles/200406/
t20040611_161343.html
Nepal
Burkina
Faso
Arab
gulf
region
hDp://www.eltek.com/detail.epl?cat=28971&id=2183193
Turkey
hDp://www.cellular-­‐news.com/story/Operators/37123.php
Italia
hDp://www.cellular-­‐news.com/story/Operators/38446.php
Sri
Lanka
hDp://www.cellular-­‐news.com/story/Operators/36151.php
Angola
hDp://www.amerescosolar.com/solar-­‐power-­‐solu<ons-­‐communica<ons
Lebanon
hDp://www.itgholding.com/news/1899

23. Prac3cal
case
in
Malaysia
Solar
BS
project
implementa<on
by:
Solar
Energy
Research
Ins<tute(SERI)
Universi<
Kebangsaan
Malaysia
(UKM)

24. • In
Malaysia,
total
energy
consump<on
by
Celcom
for
2014
was
820,775
GJ.
In
addi<on,
GHG
Emission
168,544
Tonnes
CO2
• Following
are
some
of
the
key
ini<a<ves
that
are
undertaken
to
reduce
energy
consump<ons
by
Celcom
operator,
Ø Solar
Hybrid
systems
on
the
sites
where
grid
power
is
unavailable.
Ø Posi<oning
telecom
equipment
outdoor
to
minimise
power
consump<on
and
space
requirement.
Ø Free
cooling
units
to
minimise
air-­‐condi<oning
requirements
on
sites.
Ø Automa<c
TRX
shutdown
in
the
hours
when
there
is
no
traffic
detected
(non-­‐busy
hours)

25. Case
Study:
Feasibility
Study
of
Green
Wireless
Network
for
Malaysia
Case
Study
Part
1:
Energy
op<miza<on
of
off-­‐grid
system
for
remote
LTE-­‐BS
Part
2:
Coopera<on
management
among
solar
powered
LTE-­‐BSs
for
sub-­‐urban
areas

26. Cont’d
0
1
2
3
4
5
6
7
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Daily
Radia3on
(kWhm2d)
Sabah
Perlis
Kedah
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0
1
2
3
4
5
6
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Clearness
Index
Daily
Radia3on
(kWhm2d)
Daily
Radia<on
Clearness
Index
Poten3al
of
Solar
in
Malaysia
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2016).
Green
wireless
network
op3misa3on
strategies
within
smart
grid
environments
for
Long
Term
Evolu3on
(LTE)
cellular
networks
in
Malaysia/.
Renewable
Energy,
85,
157-­‐170.

27. BS
Subsystem
Item
Nota3on
Unit
Macro
PA
Max
transmit
(rms)
power,
Pmax
W
39.8
Max
transmit
(rms)
power
dBm
46.0
PA
efficiency,
µ
%
38.8
Total
PA
(PPA)=
W
102.6
TRX
PTX
W
5.7
PRX
W
5.2
Total
RF
(PRF)
W
10.9
BB
Radio
(inner
Rx/Tx)
W
5.4
Turbo
code
(outer
Rx/Tx)
W
4.4
Processor
W
5.0
Total
BB
(PBB)
W
14.8
DC-­‐DC
loss,
σDC
%
6.0
Cooling
loss,
σcool
%
9.0
AC-­‐DC
(main
supply)
loss,
σMS
%
7.0
Total
per
TRX
=
W
160.8
Number
of
sectors
#
3
Number
of
antennas
#
2
Total
number
of
NTRX
chains,
Pin=
NTRX
×
Total
per
TRX
W
964.9
µ
maxP
( )( )( )MScoolDC
BBRFPA PPP
σσσ −−−
++
111
Power
consump3on
of
the
LTE-­‐BS
hardware
elements
G
Auer,
O
Blume,
V
Giannini,
I
Godor,
M
A
Imran,
Y
Jading,
E
Katranaras,
M
Olsson,
D
Sabella,
P
Skillermark,
W
Wajda,
Energy
efficiency
analysis
of
the
reference
systems,
areas
of
improvements
and
target
breakdown.
EARTH
project
report,
Deliverable
D2.3
(2010).

29. HOMER for hybrid power system modeling
• NPC
represents
the
system’s
life
cycle
cost
• Assesses
costs
within
the
project
life<me;
ini<al
set-­‐
up,
component
replacements
and
maintenance
• Project
life<me:
20
years
• Others:
dual-­‐tracking
system,
SPV
cost:
$4/W

30. Part
I
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2015).
Energy
Op3miza3on
of
Hybrid
Off-­‐Grid
System
for
Remote
Telecommunica3on
Base
Sta3on
Deployment
in
Malaysia.
EURASIP
Journal
on
Wireless
Communica,ons
and
Networking,
2015:64.
Energy
Op3miza3on
of
Off-­‐Grid
System
for
Remote
LTE-­‐BS

31. Energy
Model
Economic
Factors
DG
Factors
Daily
solar
(kWh/m2)
SPV
(kW)
DG
(kW)
BaDery
(unit)
Inverter
(kW)
Ini<al
Capital
Opera<ng
($/yr)
NPC
($)
Diesel
(L)
DG
(h)
5.1
2
1
4
1.5
$11,210
1,993
40,188
1,880
6,091
5.2
2
1
4
1.5
$11,210
1,980
40,000
1,866
6,039
5.3
2
1
4
1.5
$11,210
1,968
39,820
1,854
5,999
5.4
2
1
4
1.5
$11,210
1,956
39,653
1,840
5,954
5.5
2
1
4
1.5
$11,210
1,946
39,497
1,830
5,923
Ø The
op<mal
size
of
the
solar
energy
system
is
obviously
the
same
for
all
solar
radia<on
rates
proposed
(5.1
-­‐
5.5
kWh/m2/day).
Ø However,
the
energy
contribu<on
differs,
with
the
contribu<on
of
energy
from
the
solar
power
system
increasing
with
increasing
radia<on
rate.
1.
Op<miza<on
Criteria
Results

32. 2.
Energy
Yield
Results
(Cont’d)

33. Cash
flow
summary
of
the
SPV/DG
hybrid
power
system
within
the
project
life<me
at
5.1
kWh/m2/day.
3.
Cash
Flow
Results
(Cont’d)

34. Comparison
between
Malaysia
and
Germany
The
Net
Present
Cost

35. Part
II
M.
H.
Alsharif,
R.
Nordin,
and
M.
Ismail
(2015).
Intelligent
Coopera3on
Management
among
Solar
Powered
Base
Sta3ons
towards
a
Green
Cellular
Network
in
a
Country
with
an
Equatorial
Climate.
Telecommunica,on
Systems.
Intelligent
Coopera3on
Management
Among
Solar
Powered
LTE-­‐BSs
for
urban
areas

36. 1. LTE Network Topology
Key
challenge:
coverage
2. Problem Formulation
Intelligent
Coopera3on
Management
Among
BSs

37. Results
(Cont’d)
Cell radii versus receiver sensitivity power
for different MCSs
Data rate

38. Optimal design of the hybrid PV/electric grid system for master cell (operates 24 hours)
Optimal design of the hybrid PV/electric grid system for cell operates at high traffic only (13 hours)
1. Optimisation Criteria
Results

39. 2. Energy Yield
Results
(Cont’d)
4,290
4,407
4,524
4,177
4,281
5,074
5,040
4,997
5,112
5,059
4,920
4,940
4,960
4,980
5,000
5,020
5,040
5,060
5,080
5,100
5,120
5,140
4,000
4,100
4,200
4,300
4,400
4,500
4,600
5.1
5.2
5.3
5.4
5.5
Grid
Purchases
(kWh/yr)
PV
Produc3on
(kWh/yr)
Global
Solar
(kWh/m2/day)
SPV
contribu<on
for
master
cell
EG
contribu<on
for
master
cell
2,574
2,644
2,715
2,784
2,378
2,691
2,663
2,635
2,607
2,781
2,500
2,550
2,600
2,650
2,700
2,750
2,800
2,100
2,200
2,300
2,400
2,500
2,600
2,700
2,800
2,900
5.1
5.2
5.3
5.4
5.5
Grid
Purchases
(kWh/yr)
PV
Produc3on
(kWh/yr)
Global
Solar
(kWh/m2/day)
SPV
contribu<on
for
cell
operates
13
hrs
EG
contribu<on
for
cell
operates
13
hrs
Master cell
Cell operates at high traffic only (13 hours)

40. Results
(Cont’d)
-­‐14,000
-­‐12,000
-­‐10,000
-­‐8,000
-­‐6,000
-­‐4,000
-­‐2,000
0
2,000
4,000
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Nominal
Cash
Flow
($)
Year
Number
Salvage
($
3,719)
Replacement
Cost
($)
O&M
Cost
($
800)
Capital
Cost
($
12,200)
Replacement
BaDeries
Replacement
Inverter
3. Cash Flow
Cash
flow
summary
of
the
hybrid
power
system
within
the
project
life<me
at
5.1
kWh/m2/day
for
master
cell

41. Future direc*ons & challenges related to
green wireless
• 5G
Networks:
Adjustments
in
massive
MIMO
(antenna
switching
off/on)
at
high
traffic
load
condi<ons,
with
the
BSs
switching
off/on
technique
• Energy-­‐harves<ng,
such
as,
energy
harves<ng,
e.g.:
RF,
mechanical,
relay,
etc.
• Inves<ga<on
of
coopera<on
between
mobile
network
providers
(switching
off/on)
in
the
same
geographical.

42. More details…
Fundamentals
and
Applica<ons
of
Green
Communica<on
for
Current
and
Future
Mobile
Networks
• Monday,
23rd
November
2015
• Hilton
Hotel
Kuching
Acknowledgement:
Project
supported
by
Universi<
Kebangsaan
Malaysia
(UKM),
under
Grant
Ref:
ETP-­‐2013-­‐072