A Microstrip Line Based Approach for the Evaluation
of EBG Frequency Band by Its CRLH/ZOR
Characteristics
L. Peng
1,2
, J. Y. Xie
1,2
, X. Jiang
1
, S. M. Li
1,3
1
Guangxi Wireless Broadband Communication and Signal Processing Key Laboratory, Guilin University of Electronic
Technology, Guilin, 541004, Guangxi, China
2
Guangxi Experiment Center of Information Science, Guilin, 541004, Guangxi, China
3
Guangxi University of Science and Technology, Liuzhou, 545006, Guangxi, China
Abstract-The proposed microstrip line based approach for
electromagnetic band-gap (EBG) investigation defines the band-
gap through the detection of the resonant frequencies of f
sh
and
f
se
, while conventional approaches of dispersion diagram
calculation model, TEM waveguide model, and suspended
microstrip line model directly show the band-gap. The proposed
approach is based on composite right/left handed (CRLH) and
zeroth-order resonator (ZOR) theories, then, the resonant
frequencies f
sh
and f
se
of EBG structure can be detected by our
designed microstrip line based approach. Thereafter, the band-
gap of an EBG structure surface is defined as it is delimited by
the two resonant frequencies. Compared to the conventional
approaches, our proposed approach has many advantages, such
as computer resources and time-alleviated, fast prediction of the
resonant frequencies and band-gap, and easy of construction and
directly measurement. The approach is validity by full wave
simulations.
Key words: Microstrip line, EBG, ZOR, CRLH
I. INTRODUCTION
Since the mushroom-type electromagnetic bandgap (MT-
EBG) structure was introduced by Sievenpiper [1], this kinds
of EBG structures have become an active research area in the
microwave and antenna community due to their compact size
and applications derived from their particular characteristics
of surface wave suppression and in-phase reflection
coefficient properties [1-7]. The surface wave suppression
property is used to reduce the mutual coupling between
microstrip antenna array elements [4], or suppress ground
bounce noise (GBN) in high-speed circuits [5]. Low-profile
antenna designs are beneficial from their in-phase reflection
coefficient property [6-7]. In virtue of practical applications of
EBG structures, it is urgent to obtain design (simulation)
approach that can fast and accurately explore the
characteristics of EBG structure. Additional requirements for
desired design approach are easy construction of the model
and directly measurement of the band-gap or resonant
frequencies. The convention approaches for band-gap/resonant
frequencies detection include dispersion diagram calculation
model [8], TEM waveguide model [9], and suspended
microstrip line model [10]. The conventional approaches have
their advantages and disadvantages. Then, a novel microstrip
line based approach is introduced as a complementarily and
Fig. 1 MT-EBG. (a) unit, (b) array and (c) equivalent circuit model.
reinforcing of the investigation approaches of EBG. Compare
to the conventional approaches, our proposed microstrip line
based approach has many advantages, such as, computer
resources and time-alleviated (compare to the dispersion
diagram calculation model), no supporting material effect and
easier of construction (compare to the suspended microstrip
line model), and directly measurement (compare to dispersion
diagram calculation model and TEM waveguide model), etc.
The proposed approach is based on composite right/left
handed (CRLH), which define MT-EBG structure's band-gap
by resonant frequencies f
sh
and f
se
, and zeroth-order resonator
(ZOR) theories, which help to detect the two resonant
frequencies. According to the above theories, we can simply
design two EBG models couple to microstrip line to locate the
two resonant frequencies, respectively. The results obtained
from the proposed approach are compared to the dispersion
Brillouin diagrams, and found the proposed approach is quiet
accuracy.
II. T
HEORY
In [1], the MT-EBG surface was equivalent to a parallel LC
resonator, which is help to understand the structure. However,
the parallel LC resonator model is very roughness, and may
miss lost of information about the structure. Now, let's
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978-1-4763-644-4 /1/$31.00 ©201 IEEE