This document presents the design of a dual-band rectenna for RF energy harvesting in wireless sensor networks. A microstrip patch antenna was designed to resonate at 1.8 GHz and 2.4 GHz. A dual-band matching network was also designed to provide maximum power transfer from the antenna to the rectifier circuit. The rectifier circuit uses a HSMS-2820 diode and provides a power conversion efficiency of 58.5% at 1.8 GHz and 83.7% at 2.4 GHz. While the voltages obtained are not sufficient to directly power sensor nodes, the harvested energy could be stored using super capacitors or microbatteries for later use by the wireless sensors. The rectenna design demonstrates effective

1. See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/328880116
Rectanna Design for RE Energy Harvesting in Wireless Sensor Networks
Conference Paper · May 2015
CITATIONS
0
READS
216
3 authors, including:
Some of the authors of this publication are also working on these related projects:
Master thesis View project
An Adaptive Time slot Allocation for Statistical QoS guarantees in Wireless Networks using Cross-layer approach View project
Indumathi Ganesan
Mepco Schlenk Engineering College
115 PUBLICATIONS 120 CITATIONS
SEE PROFILE
All content following this page was uploaded by Indumathi Ganesan on 11 January 2020.
The user has requested enhancement of the downloaded file.

2. 2015 IEEE INTERNATIONAL CONFERENCE ON ELECTRICAL, COMPUTER AND COMMUNICATION TECHNOLOGIES
1389
Rectenna Design for RF Energy Harvesting in
Wireless Sensor Networks
1
G.Indumathi & 2
K.Karthika
Dept. of ECE, Mepco Schlenk Engineering College, Sivakasi, India.
1gindhu@mepcoeng.ac.in & 2karthika.svk@gmail.com
Abstract— In the wireless world, wireless power transfer
is one of the emerging technologies. Energy harvesting is the
reason behind the success of wireless sensor networks.
Though wireless sensor networks find lots of applications in
agriculture, an industry etc, one of the major constraints is
its power consumption. The solution for this problem can be
either power consumption reduction or external power
supply by means of energy harvesting. Since lots of RF
sources are available in the present scenario, this paper
concentrates on RF energy harvesting in order to supply
power to the wireless sensor nodes. This work presents the
design of rectenna which can harvest RF power from two
different bands such as 1.8 GHz (GSM band) and 2.4 GHz
(ISM band). The designed antenna radiates 3.201 dBm and
4.771 dBm power at 1.8 GHz and 2.4 GHz respectively and
these powers are given as input to the rectifier circuit which
converts RF power into DC voltage. The rectifier circuit
gives Power Conversion Efficiency (PCE) of about 58.545%
at 1.8 GHz with the output voltage of 0.459 V for the input
0.839 V. PCE is 83.729% at 2.4 GHz with the output voltage
of 0.768 V for the input 0.892 V. Advanced Design System
(ADS) 2009 is used for simulation. Diode used here is HSMS-
2820 diode from Avago technologies.
Keywords — Dual band; Antenna; Rectifier; Power
Conversion Efficiency; Radio Frequency (RF ) Energy
Harvesting.
I.INTRODUCTION
In recent technologies, wireless power transfer has
occupied a great attention. Energy can be harvested by
means of different ways includes solar energy harvesting,
RF energy harvesting, wind energy harvesting, thermal
energy harvesting etc. Energy harvesting is used for
charging of mobile devices [3]. In the inter-connected
world, the number of mobile users are drastically
increasing day-by-day. Also the use of Wi-Fi connections
in colleges, industries, software companies makes the
availability of RF sources in a large manner. This leads to
ambient RF power harvesting [5].
In this paper we presented the design of dual-band antenna
for RF energy harvesting system. The antenna has resonant
frequencies at 1.8 GHz and 2.4 GHz with the gain of 5.88
dB and 5.0255 dB respectively. Similarly the rectifier
circuit is also designed which can operate at desired
frequency bands. The rectifier circuit gives the power
conversion efficiency (PCE) of about 58.545% at 1.8 GHz
and 83.729% at 2.4 GHz. The basic block diagram of
Fig. 1 Block diagram of Rectenna
rectenna is shown in the Fig.1. This consists of RF sources
as their input and antenna is used to harvest power from
those sources. Matching circuit is used between the
rectifying circuit and antenna for maximum power
transfer from antenna to the rectifier. Diode is used in the
rectifying circuit for converting input RF power into
output DC voltage. Filter can be used at the end to remove
the harmonics generated by the diode. Finally the
harvested voltage is given to the load.
II.RECTENNA DESIGN
Antenna Design
First step in rectenna design is to design an antenna.
Initially the micro-strip patch antenna was designed to
operate at 2.4 GHz. The antenna resides on a 1.6 mm FR4
substrate with dielectric constant, r = 4.4 and a loss
tangent, = 0.01. The calculated dimensions of the
micro-strip patch antenna includes, width of the patch is
W=38.03 mm, extended length is 0.783 mm, effective
dielectric constant is 4.08 and length of the patch is L=29.5
mm. Inset feed method is used. The designed antenna
resonates well at 2.4 GHz. The Fig.2 shows the layout of
the antenna. To make this patch resonate at dual frequency
bands, a slot is made on it. Thus the antenna was designed
to resonate at two desired frequency bands such as 1.8
GHz and 2.4 GHz.
The proposed antenna appears like inverted E-shape and it
has the radiated power of 0.00209 Watts, directivity of
6.18105 dB and gain of 5.88572 dB for the corresponding
frequency band of 1.8 GHz and it has the radiated power
of 0.00308 Watts, directivity of 5.55555 dB and gain of
5.0256 dB for the corresponding frequency band of 2.4
GHz.

3. 2015 IEEE INTERNATIONAL CONFERENCE ON ELECTRICAL, COMPUTER AND COMMUNICATION TECHNOLOGIES
1390
Fig. 2 Layout of the dual-band antenna
Dual Band Matching Network
Fig. 3 Design of dual band matching network:
a) Single band matching network at band 1
b) Single band matching network at band 2
c) Dual band matching network
It is necessary to design dual-band matching network [1]
to provide maximum power transfer from antenna to the
rectifier. Two single band matching network can be
converted into the dual-band matching network by the
compliance of reactance and susceptance at the single
band matching network. Formulas to calculate the
capacitances and inductances of series-parallel resonators
are given by (1) and (2) respectively. The capacitances
and inductances of the shunt-series LC can be calculated
from (3) and (4) respectively. Xm1 and Xm2 represent the
reactance of the first and second band respectively. B12
and B22 are the susceptances of the first and second band
matching network.
)
ω
X
ω
(X
ω
ω
)
ω
(ω
X
X
L
)
ω
(ω
X
X
ω
X
ω
X
C
1
1
2
2
2
1
2
1
2
2
2
1
2
1
2
2
2
1
2
1
1
2
m
m
m
m
md
m
m
m
m
md
−
−
=
−
−
=
Fig. 4 Schematic of the rectifier
)
ω
B
ω
(B
ω
ω
)
ω
(ω
B
B
C
)
ω
(ω
B
B
ω
B
ω
B
L
1
21
2
22
2
1
2
1
2
2
22
21
2
2
1
2
2
22
21
2
21
1
22
2
−
−
=
−
−
=
d
d
From the calculation, the component values of the
proposed dual-band M/N shown in Fig. 3 are L1d = 1.4
nH, C1d = 0.51 pF, L2d = 5.89 nH, C2d = 0.56 pF, L3d = 0.6
nH, and C3d = 11 pF.
The Fig.4 shows the schematic of the rectifier. Radiated
powers which are obtained at the two desired frequencies
such as 1.8 GHz and 2.4 GHz using the designed antenna
are given as input to the rectifier circuit. Then the
matching circuit is placed in between the HSMS-2820
diode and the input. The diode will produce some
harmonics. In order to reduce those harmonics we are
placing a CLC filter and the output of the diode is given to
that filter. The current can be measured using I_probe and
the power can be measured by placing P_probe. Diode
converts the input RF power into DC current. The term is
used to terminate the circuit. Input and output voltages
can be obtained with the help of HB simulation and S11
parameter can be obtained with the help of S-parameter
simulation.
III.SIMULATION RESULTS
Advanced Design System tool is used for simulation. ADS
is the world’s leading electronic design automation
software for RF, microwave, and high speed digital
applications. The Fig. 5 shows the S11 parameter of the
antenna. S11 parameter denotes return loss. This represents
how much power is reflected from the antenna. If S11= 0
dB, then all the power is reflected from the antenna and
nothing is radiated. The return loss should be minimum for
the antenna. Here the design has achieved the return loss of
about -25.339 dB at around 1.8 GHz and -21.273 dB at 2.4
GHz.
(1)
(2)
(3)
(4)

4. 2015 IEEE INTERNATIONAL CONFERENCE ON ELECTRICAL, COMPUTER AND COMMUNICATION TECHNOLOGIES
1391
Fig. 5 Simulated S11 parameter of the antenna
Fig. 6 Simulated S11 parameter of the rectifier
The proposed antenna has the radiated power of 0.00209
Watts, directivity of 6.18105 dB and gain of 5.88572 dB
for the corresponding frequency band of 1.8 GHz and it
has the radiated power of 0.00308 Watts, directivity of
5.55555 dB and gain of 5.0256 dB for the corresponding
frequency band of 2.4 GHz.
The Fig.6 shows the S11 parameter of the proposed
rectifier. S11 parameter is represents return loss. The
return loss should be minimum for the rectifier. If the
return loss is minimum, then it implies that most of the
received power gets delivered to the load. Here the design
has achieved the return loss of about -10.018 dB at 1.8
GHz and -21.230 dB at 2.4 GHz. Power Conversion
Efficiency (PCE) is an important parameter in case of
rectenna. This gives how efficiently the rectifier converts
the input RF power into DC voltage. The measure of
magnitude of input and output voltages can be done using
Harmonic Balance (HB) Simulation which are recquired to
calculate the PCE. The PCE can be calculated as follows.
100
P
P
PCE *
)
( RF
out
= (5)
Load
DC
out R
V
P
2
= (6)
where RLoad - Load resistance, VDC - output voltage, PRF -
incident RF power, Pout – Output RF power.
The Fig. 7 shows the PCE at 1.8 GHz. The marker m11
indicates that the designed circuit gives the PCE of
58.545% at 1.8 GHz.
Fig. 7 PCE @ 1.8 GHz
Fig. 8 PCE @ 2.4 GHz
TABLE I. CONSOLIDATED RESULTS
RLoad
(Ohms)
Pin @
1.8
GHz(Wa
tts)
Pin @
2.4
GHz(Wa
tts)
PCE @
1.8 GHz
(%)
PCE @
2.4
GHz(%)
235 0.00209 0.003 58.545 83.729
The Fig.8 shows the PCE at 2.4 GHz. The marker m12
indicates that the designed circuit gives the PCE of
83.729% at 2.4 GHz. The consolidated results of the work
have been given in Table 1.
IV. CONCLUSION
In rectenna design, an antenna which is designed can
radiate 3.201 dBm and 4.771 dBm power at 1.8 GHz and
2.4 GHz respectively. It exhibits return loss of about -
25.339 dB and -21.273 dB at desired frequencies. This
implies that most of the power given to the antenna gets
radiated. The designed antenna exhibits the gain of 5.88 db
and 5.0255 db at 1.8 GHz and 2.4 GHz respectively. This
gives the directivity of about 6.18 db and 5.55 db at
desired frequencies such as 1.8 and 2.4 GHz respectively.
PCE is 58.545% at 1.8 GHz with the output voltage of
0.459 V for the input 0.839 V. PCE is 83.729% at 2.4 GHz
with the output voltage of 0.768 V for the input 0.892 V.
Thus the designed rectenna shows good performance with

5. 2015 IEEE INTERNATIONAL CONFERENCE ON ELECTRICAL, COMPUTER AND COMMUNICATION TECHNOLOGIES
1392
good PCE when two RF waves are fed simultaneously. In
wireless sensor networks, the sensor nodes can either
directly powered using rectenna or the harvested voltage
can be stored using some storage devices. Since the
voltages obtained at these frequencies are not sufficient to
directly power the sensor nodes, it can store using a super
capacitor or micro batteries for further use. In order to
increase the amount of harvested voltage, this work can be
extended by including the voltage multiplier in the rectifier
circuit and also include some more bands such as 900
MHz (GSM band), 5.8 GHz (ISM band).
REFERENCES
[1]. Phirun Kim, Girdhari Chaudhary, and Yongchae Jeong “A
Dual-Band RF Energy Harvesting Using Frequency Limited
Dual-Band Impedance Matching,” in Electromagnetics
Research, Vol. 141, 443–461, 2013.
[2]. Y. J. Ren, Muhammad F. Farooqui, K. Chang, "A Compact
Dual-Frequency Rectifying Antenna With High-Orders
Harmonic-Rejection", IEEE Transactions on Antennas And
Propagation, Vol. 55, no. 7, pp. 2110-2113, July 2007.
[3]. H. Jabbar, Y. S. Song and T. T. Jeong, “RF energy harvesting
system and circuits for charging of mobile devices,” IEEE
Transactions on Consumer Electronics, Vol. 56, no. 1, pp. 247-
253, Feb. 2010.
[4]. Long Shen, Xuexia Yang,“A novel rectifier circuit operating at
dual-frequencies of 1.8 GHz and 2.4 GHz,” in Microwave
Workshop Series on RF and Wireless Technologies for
Biomedical and Healthcare Applications (IMWS-BIO), 2013
IEEE MTT-S International.
[5]. H. Sun, Y. Guo, M. He and Z. Zhong, “A dual-band rectenna
using broadband yagi antenna array for ambient RF power
harvesting,” in IEEE Antennas and Wireless Propagation
Letters, Vol. 12, pp. 918-921,2013.
[6]. Hu-cheng Sun, Yong-xin Guo, Senior Member, IEEE, Miao He,
and Zheng Zhong, “Design of a high-efficiency 2.45-GHz
rectenna for low-input-power energy harvesting,” in IEEE
antennas and wireless propagation letters, Vol. 11, pp. 929 –
932, 2012.
[7]. S. Bin Alam, M. S. Ullah and S. Moury, “Design of A Low
Power 2.45 GHz RF Energy Harvesting Circuit for Rectenna,”
in IEEE proc. at International conference on Informatics,
Electronics and Vision, pp. 1-4,May 2013.
View publication stats
View publication stats