A design procedure for active rectangular microstrip patch antenna
0 likes1,600 views
This document presents a design procedure for an active rectangular microstrip patch antenna operating in the X-band frequency range. It begins with the design of the passive antenna element using standard equations. Appropriate input and output matching circuits are then examined and an amplifier is designed. The passive antenna is connected to the amplifier input to form the overall active antenna structure, which is simulated using ADS software. The results show improvements in characteristics like gain and bandwidth for the active antenna compared to the passive design alone. A comparison of the key characteristics of passive versus active antenna designs is also provided.
![INTERNATIONAL JOURNAL OF ELECTRONICS AND
International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
COMMUNICATION–ENGINEERING Issue 1, January- June (2012), (IJECET)
0976 – 6464(Print), ISSN 0976 6472(Online) Volume 3, & TECHNOLOGY © IAEME
ISSN 0976 – 6464(Print)
ISSN 0976 – 6472(Online)
Volume 3, Issue 1, January- June (2012), pp. 123-129
IJECET
© IAEME: www.iaeme.com/ijecet.html
Journal Impact Factor (2011): 0.8500 (Calculated by GISI)
©IAEME
www.jifactor.com
A DESIGN PROCEDURE FOR ACTIVE RECTANGULAR
MICROSTRIP PATCH ANTENNA
1
Mahmoud Abdipour, Gholamreza Moradi, Reza Sarraf Shirazi
2 2
1 Department of Electrical Engineering, Azad Branch, Islamic Azad
University,Arak,Iran (Mahmoud.abdipour@gmail.com)
2 Department of Electrical Engineering,Amirkabir University,Tehran, Iran
(ghmoradi@aut.ac.ir)
2 Department of Electrical Engineering,Amirkabir University,Tehran,Iran
(sarraf@aut.ac.ir)
ABSTRACT
In this paper a design procedure for active rectangular microstrip patch
antenna is presented. The design procedure begins with the theory of passive
part. Then appropriate input and output matching circuits are examined. Finally,
with connecting passive antenna as amplifier input, the overall structure is
designed and simulated. Also a comparison between passive and active antenna
is done. The used substrate is RT/DOUROID 5880 with relative permittivity of
2.2 and thickness of 1.588 mm .The ADS software and its full wave Momentum
is used for simulation. The results show a relative improvement in the active
antenna characteristics with respect to passive antenna.
Keywords- Microstrip antenna, Active antenna , X-band, ADS 2009
1. INTRODUCTION
In recent years, active antenna has been welcomed because of their vast
advantages. In fact, using this structure in addition to the advantages of passive
antenna, can be overcome the disadvantages of these antenna such as small
bandwidth, large noise figure and large length [1]. In active antenna structure, a
passive antenna is placed beside of amplifier. If the antenna to be used as a load
to the amplifier, and if antenna to be used as an input to the amplifier, antenna
is transmitter and receiver, respectively. Important considerations in the design
of active antenna include high gain and smooth in all its bandwidth, low noise
123](https://image.slidesharecdn.com/adesignprocedureforactiverectangularmicrostrippatchantenna-121125011550-phpapp01/85/A-design-procedure-for-active-rectangular-microstrip-patch-antenna-1-320.jpg)
![International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME
figure, appropriate matching in input and output, linear operation and the small
size. Among antennas that are used as passive part for such structures,
rectangular microstrip patch antenna are the most popular because of ease of
analysis and fabrication, and their attractive radiation characteristics[2]. Feed
type, plays an important role in the design of patch antenna. an microstrip patch
antenna can be feed with coaxial probe or microstrip line that in the meanwhile
microstrip line is preferable because this line can be considered to continue of
patch which help to better and easier input/output matching. Since the input
impedance of a patch is often large, we usually use inset-fed method for input
impedance matching with the line characteristic impedance. In this method
how much we move from the edge toward the patch center, patch impedance is
reduced, so that in patch center is equal to zero[3].
2. PATCH ANTENNA DESIGN
Fig.1 shows the patch geometry of an inset-fed rectangular patch. Basic
parameters include length of patch( L ) , width of patch ( W ) , the notch width
p p
(g), the inset distance from the radiating edge(d) and width of feed line (w).
Approximate equations related on the rectangular antenna analysis and design
can be calculated as follows:
The width of the antenna can be determined by [4]:
vo 2
WP =
2 fr εr +1 (1)
The effective dielectric constant is given by [5],[6]:
−1/2
εr +1 εr −1 h
ε ref f = + 1 + 12 for W p / h > 1
2 2 (2)
Wp
Normalized extension of the length, ∆L, which is due to open ended
transmission line can be obtained by [7]:
Wp
(ε ref f + 0.3) + 0.264
∆L
= 0.412 h
h Wp (3)
(ε ref f − 0.258 ) + 0.8
h
The actual length of the patch, Lp , can be expressed by [3]:
νo
Lp = − 2∆L
2 f r ε reff (4)
The notch width, g, can be obtained by using [8]:
νo 4.6 × 10 − 14 f
fr = +
2 × ε ref f g 1.01
(5)
νo 4.65 × 10−12
g=
2 × ε ref f
f (6)
In this equations, is resonant frequency and f is operating frequency.
We can calculate the value of Z as: 0
124](https://image.slidesharecdn.com/adesignprocedureforactiverectangularmicrostrippatchantenna-121125011550-phpapp01/85/A-design-procedure-for-active-rectangular-microstrip-patch-antenna-2-320.jpg)
![International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME
π
Z o = Rin cos 2 d
L
p (7)
Where, d , is the inset distance from the radiating edge, and Rin is the resonant
input resistance when the patch is fed at a radiating edge.
We can calculate R as [9]: in
1
Rin =
2 ( G1 + G12 ) (8)
Where, G1 , is the conductance of a single slot and can be obtained by:
2
koW p
sin
π
Cos θ
1 2 sin 3 θ dθ
120 π 2 ∫
G1 =
0
cos θ
(9)
and , G , is the mutual conductance and can be calculated using:
12
2
koW p
sin
π
Cos θ
1 2 J k L sin θ sin 3 θ dθ
120 π 2 ∫ o( o p
G12 =
cos θ
)
0
(10)
J0 , is the Bessel function of the first kind of order zero.
Fig.1 Geometry of a microstrip patch antenna
Also the width of feed line assuming ZC = Z 0 can be calculated using [1]:
120π
ZC = (11)
W W
ε reff h + 1.393 + 0.667 ln h + 1.444
The final values are determined through extensive numerical simulations.
2. AMPLIFIER DESIGN
Application is an essential factor in amplifier part design of an active
antenna. For example, for transmitter applications, the design goals are to
achieve higher gain and more bandwidth. For reception applications, problem
about noise figure is design goal. This is a criterion for transistor selection, so
that for transmitter antenna, HBT transistors are preferred because of their high
gain. Whereas for reception application, HEMT transistors are good choices
because of their low noise.
125](https://image.slidesharecdn.com/adesignprocedureforactiverectangularmicrostrippatchantenna-121125011550-phpapp01/85/A-design-procedure-for-active-rectangular-microstrip-patch-antenna-3-320.jpg)
![International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME
Various stage of amplifier design for the active antenna is shown in the
following flow diagram.
Fig.2 Amplifier design flow diagram
The final stage is integration amplifier part with the passive antenna.
4. DESIGN EXAMPLE
In this section, an active microstrip patch antenna is designed and we will
review the effect of using active part beside a passive antenna. Designing is
done for X-band with 10 GHz center frequency. The substrate is RT/DUROID
5880 that its characteristics are given in Table.1.
Table 1 RT/DUROID 5880 characteristics
Substrate εr h, mm T,mm
RT/DUROID
2.2 1.588 0.035
5880
ADS software is used to simulate. Using equation [1]-[11], we can calculate
the physical dimensions of microstrip patch antenna as shown in Table.2.
126](https://image.slidesharecdn.com/adesignprocedureforactiverectangularmicrostrippatchantenna-121125011550-phpapp01/85/A-design-procedure-for-active-rectangular-microstrip-patch-antenna-4-320.jpg)
![International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME
REFERENCES
[1]Garg. R,Bahl.I,Ittipiboon.AJ, “Microstrip Antenna design handbook”, Artch
House,Boston.London.
[2] Balanis. C.A(1997), “Antenna theory: Analysis and Design,” New York,
John Wiley & Sons Inc.
[3] Basilio . L.I, et.al.(2001), “The Dependence of the input impedance on
Feed position of probe and microstrip line-fed patch antenna”, IEEE Trans.
Antenna & propagation, Vol.AP(49):45-47.
[4] James .J.R and Hall .P.S(1989),“Handbook of microstrip antennas,”Peter
Peregrinus, London,UK.
[5] Pozar,D.M., and Schaubert .D.H(1995),“Microstrip Antennas, the Analysis
and Design of microstrip Antennas and Arrays” IEEE Press, New York, USA.
[6] Bahl, I.J and Bhartia .P(1980), “ Microstrip Antenna Technology,” Artch
House, Dedham, MA.
[7] Owens .R.P(1976), “Accurate Analytical Determination of quasistatic
Microstrip Line Parameters”, The Radio and Electronic Engineer, 46 (7):360-
364.
[8] Matin, M.A and Sayeed A.I(2010), “A Design Rule for Inset-Fed
Rectangular Microstrip Patch Antenna,”WSEAS TRANSACTION on
communications;1 (9).
[9] Derneryd, A.G(1978), “A theoretical Investigation of the Rectangular
Microstrip Patch Antenna Element,” IEEE Trans. Antennas and
Propation,26(4): 532-535.
129](https://image.slidesharecdn.com/adesignprocedureforactiverectangularmicrostrippatchantenna-121125011550-phpapp01/85/A-design-procedure-for-active-rectangular-microstrip-patch-antenna-7-320.jpg)
A design procedure for active rectangular microstrip patch antenna
- 1. INTERNATIONAL JOURNAL OF ELECTRONICS AND International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN COMMUNICATION–ENGINEERING Issue 1, January- June (2012), (IJECET) 0976 – 6464(Print), ISSN 0976 6472(Online) Volume 3, & TECHNOLOGY © IAEME ISSN 0976 – 6464(Print) ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), pp. 123-129 IJECET © IAEME: www.iaeme.com/ijecet.html Journal Impact Factor (2011): 0.8500 (Calculated by GISI) ©IAEME www.jifactor.com A DESIGN PROCEDURE FOR ACTIVE RECTANGULAR MICROSTRIP PATCH ANTENNA 1 Mahmoud Abdipour, Gholamreza Moradi, Reza Sarraf Shirazi 2 2 1 Department of Electrical Engineering, Azad Branch, Islamic Azad University,Arak,Iran (Mahmoud.abdipour@gmail.com) 2 Department of Electrical Engineering,Amirkabir University,Tehran, Iran (ghmoradi@aut.ac.ir) 2 Department of Electrical Engineering,Amirkabir University,Tehran,Iran (sarraf@aut.ac.ir) ABSTRACT In this paper a design procedure for active rectangular microstrip patch antenna is presented. The design procedure begins with the theory of passive part. Then appropriate input and output matching circuits are examined. Finally, with connecting passive antenna as amplifier input, the overall structure is designed and simulated. Also a comparison between passive and active antenna is done. The used substrate is RT/DOUROID 5880 with relative permittivity of 2.2 and thickness of 1.588 mm .The ADS software and its full wave Momentum is used for simulation. The results show a relative improvement in the active antenna characteristics with respect to passive antenna. Keywords- Microstrip antenna, Active antenna , X-band, ADS 2009 1. INTRODUCTION In recent years, active antenna has been welcomed because of their vast advantages. In fact, using this structure in addition to the advantages of passive antenna, can be overcome the disadvantages of these antenna such as small bandwidth, large noise figure and large length [1]. In active antenna structure, a passive antenna is placed beside of amplifier. If the antenna to be used as a load to the amplifier, and if antenna to be used as an input to the amplifier, antenna is transmitter and receiver, respectively. Important considerations in the design of active antenna include high gain and smooth in all its bandwidth, low noise 123
- 2. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME figure, appropriate matching in input and output, linear operation and the small size. Among antennas that are used as passive part for such structures, rectangular microstrip patch antenna are the most popular because of ease of analysis and fabrication, and their attractive radiation characteristics[2]. Feed type, plays an important role in the design of patch antenna. an microstrip patch antenna can be feed with coaxial probe or microstrip line that in the meanwhile microstrip line is preferable because this line can be considered to continue of patch which help to better and easier input/output matching. Since the input impedance of a patch is often large, we usually use inset-fed method for input impedance matching with the line characteristic impedance. In this method how much we move from the edge toward the patch center, patch impedance is reduced, so that in patch center is equal to zero[3]. 2. PATCH ANTENNA DESIGN Fig.1 shows the patch geometry of an inset-fed rectangular patch. Basic parameters include length of patch( L ) , width of patch ( W ) , the notch width p p (g), the inset distance from the radiating edge(d) and width of feed line (w). Approximate equations related on the rectangular antenna analysis and design can be calculated as follows: The width of the antenna can be determined by [4]: vo 2 WP = 2 fr εr +1 (1) The effective dielectric constant is given by [5],[6]: −1/2 εr +1 εr −1 h ε ref f = + 1 + 12 for W p / h > 1 2 2 (2) Wp Normalized extension of the length, ∆L, which is due to open ended transmission line can be obtained by [7]: Wp (ε ref f + 0.3) + 0.264 ∆L = 0.412 h h Wp (3) (ε ref f − 0.258 ) + 0.8 h The actual length of the patch, Lp , can be expressed by [3]: νo Lp = − 2∆L 2 f r ε reff (4) The notch width, g, can be obtained by using [8]: νo 4.6 × 10 − 14 f fr = + 2 × ε ref f g 1.01 (5) νo 4.65 × 10−12 g= 2 × ε ref f f (6) In this equations, is resonant frequency and f is operating frequency. We can calculate the value of Z as: 0 124
- 3. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME π Z o = Rin cos 2 d L p (7) Where, d , is the inset distance from the radiating edge, and Rin is the resonant input resistance when the patch is fed at a radiating edge. We can calculate R as [9]: in 1 Rin = 2 ( G1 + G12 ) (8) Where, G1 , is the conductance of a single slot and can be obtained by: 2 koW p sin π Cos θ 1 2 sin 3 θ dθ 120 π 2 ∫ G1 = 0 cos θ (9) and , G , is the mutual conductance and can be calculated using: 12 2 koW p sin π Cos θ 1 2 J k L sin θ sin 3 θ dθ 120 π 2 ∫ o( o p G12 = cos θ ) 0 (10) J0 , is the Bessel function of the first kind of order zero. Fig.1 Geometry of a microstrip patch antenna Also the width of feed line assuming ZC = Z 0 can be calculated using [1]: 120π ZC = (11) W W ε reff h + 1.393 + 0.667 ln h + 1.444 The final values are determined through extensive numerical simulations. 2. AMPLIFIER DESIGN Application is an essential factor in amplifier part design of an active antenna. For example, for transmitter applications, the design goals are to achieve higher gain and more bandwidth. For reception applications, problem about noise figure is design goal. This is a criterion for transistor selection, so that for transmitter antenna, HBT transistors are preferred because of their high gain. Whereas for reception application, HEMT transistors are good choices because of their low noise. 125
- 4. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME Various stage of amplifier design for the active antenna is shown in the following flow diagram. Fig.2 Amplifier design flow diagram The final stage is integration amplifier part with the passive antenna. 4. DESIGN EXAMPLE In this section, an active microstrip patch antenna is designed and we will review the effect of using active part beside a passive antenna. Designing is done for X-band with 10 GHz center frequency. The substrate is RT/DUROID 5880 that its characteristics are given in Table.1. Table 1 RT/DUROID 5880 characteristics Substrate εr h, mm T,mm RT/DUROID 2.2 1.588 0.035 5880 ADS software is used to simulate. Using equation [1]-[11], we can calculate the physical dimensions of microstrip patch antenna as shown in Table.2. 126
- 5. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME Table 2 The physical dimensions of microstrip patch antenna Length of the patch,LP, in mm 9.6 Width of the patch,WP, in mm 11.86 Position of inset fed point,d,in mm 2.5 Width of the microstrip feed 2 line,W,in mm Notch width,g,in mm 0.2 The simulation results of the designed patch are given in Fig.3.As shown in this figure, the antenna has a good matching performance. 200 0 m1 indep(m1)= 1.000E10 plot_vs(real(Zin), freq)=49.374 -5 150 dB(S(1,1)) -10 real(Zin) 100 m2 -15 freq=10.05GHz m1 dB(S(1,1))=-22.399 50 -20 m2 0 -25 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0 freq, GHz freq, GHz (a) (b) Fig.3 The simulation results (a) The Input Impedance (b) The S11 . Using given flow diagram for the design of the amplifier and connect to the passive part and overall circuit layout extraction we reach to following strucure . Fig 4 Final layout of receiver active antenna 127
- 6. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME Simulation results are shown in the following 0.665 1.330 1.325 0.660 m2 m1 freq=10.00GHz freq=10.00GHz nf(2)=0.650 1.320 VSWR2=1.312 0.655 m2 VSWR2 nf(2) 1.315 m1 0.650 1.310 0.645 1.305 0.640 1.300 0.635 1.295 9.90 9.92 9.94 9.96 9.98 10.00 10.02 10.04 10.06 10.08 10.10 9.90 9.92 9.94 9.96 9.98 10.00 10.02 10.04 10.06 10.08 10.10 freq, GHz freq, GHz (a) (b) 1.8 12 m3 m4 1.7 freq=10.00GHz VSWR1=1.391 9 1.6 VSWR1 dB(S(2,1)) 6 1.5 3 m3 m4 1.4 freq=10.00GHz dB(S(2,1))=11.132 0 1.3 9.90 9.92 9.94 9.96 9.98 10.00 10.02 10.04 10.06 10.08 10.10 9.90 9.92 9.94 9.96 9.98 10.00 10.02 10.04 10.06 10.08 10.10 freq, GHz freq, GHz (c) (d) Fig.5 Results of active antenna simulation (a) VSWRout (b) NFout (c) The S21 (d) VSWRin A comparison between active and passive antennas is shown in Table.3. Table 3 A comparison between active and passive antennas Characteristic Preferable Antenna Structure Simplicity Passive Antenna Design Simplicity Passive Antenna Reliability Passive Antenna Pattern Characteristic Similar EIRP & Output Power Active Antenna Bandwidth Active Antenna Gain Active Antenna Noise Figure Active Antenna 5. CONCLUSION In this paper a procedure of designing active microstrip patch antenna was presented. Also an X-band active antenna is designed. Finally a comparison between passive and active structure is examined. 128
- 7. International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 1, January- June (2012), © IAEME REFERENCES [1]Garg. R,Bahl.I,Ittipiboon.AJ, “Microstrip Antenna design handbook”, Artch House,Boston.London. [2] Balanis. C.A(1997), “Antenna theory: Analysis and Design,” New York, John Wiley & Sons Inc. [3] Basilio . L.I, et.al.(2001), “The Dependence of the input impedance on Feed position of probe and microstrip line-fed patch antenna”, IEEE Trans. Antenna & propagation, Vol.AP(49):45-47. [4] James .J.R and Hall .P.S(1989),“Handbook of microstrip antennas,”Peter Peregrinus, London,UK. [5] Pozar,D.M., and Schaubert .D.H(1995),“Microstrip Antennas, the Analysis and Design of microstrip Antennas and Arrays” IEEE Press, New York, USA. [6] Bahl, I.J and Bhartia .P(1980), “ Microstrip Antenna Technology,” Artch House, Dedham, MA. [7] Owens .R.P(1976), “Accurate Analytical Determination of quasistatic Microstrip Line Parameters”, The Radio and Electronic Engineer, 46 (7):360- 364. [8] Matin, M.A and Sayeed A.I(2010), “A Design Rule for Inset-Fed Rectangular Microstrip Patch Antenna,”WSEAS TRANSACTION on communications;1 (9). [9] Derneryd, A.G(1978), “A theoretical Investigation of the Rectangular Microstrip Patch Antenna Element,” IEEE Trans. Antennas and Propation,26(4): 532-535. 129