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Miniaturized Modeling of a Quasi-Elliptic
Tri-Band Pass Filter Using a Folded Tri-Section
Stepped Impedance Resonator for Improved Performance
-- Jignesh Patoliya, Ved Vyas Dwivedi and Y P Kosta
For modern wireless telecommunication transceiver systems, research and innovation
in passive components such as multi-band small size filters operating in low range microwave regime need to be encouraged. This paper studies a
novel concept of a tri-band pass filter with special type of resonator applied for realization of printed filters at various
microwave and RF frequencies with improved electrical performance. A miniaturized and compact quasi-elliptic microstrip
tri-band pass filter is geometrically analyzed, designed, modeled and simulated using four-pole cross-coupled folded
stepped impedance resonator. By optimizing the electro-mechanical parameters of stepped impedance resonator, a
great improvement in rejection bandwidth and insertion loss is obtained. Finally, the tri-section stepped impedance
resonator-based filter has been realized using the high frequency structure simulator resulting in low insertion loss (< 0.7 dB)
and high return loss (~ -43 dB) at the desired central frequency in each of the three narrow bands. The area-size of
this prototype filter-circuit is around 35 × 24
mm2 with miniaturized volumetric dimensions of 666
mm3 which is 56% less compared to the conventional stepped impedance
resonator-based tri-section filter.
© 2010 IUP. All Rights Reserved.
A Combinatorial Method of Computing Blocking in a Loss Network with Non-Stationary Arrivals
-- Jorma Jormakka
This paper presents an efficient way to calculate a good approximation to the blocking probability in a tree-shaped
loss network consisting of exchanges and a server. The method applies to situations where the network supports a
service generating traffic which has a non-stationary arrival process and creates a focused load to the server. Examples of
such situations are mass calls, which appear in televoting and hot spots of certain application services in the internet.
The situation appears also in a military command and control system if services are concentrated to service hubs. The
traffic load is focused on the service hubs, strongly depends on the state of operation, and can create mass call type traffic.
© 2010 IUP. All Rights Reserved.
Single Layer Rectangular Microstrip Array Antenna for X-Band Applications
-- S L Mallikarjun and P M Hadalgi
This paper presents a 10-element Rectangular Microstrip
Array Antenna (10RMSAA) fed through a modified
corporate feed network. The measured experimental results show
that the bandwidth of the 10RMSAA is improved to
31.39% covering 9.14-12.54 GHz frequency range. The
proposed antenna shows an improvement in gain with
broadside radiation pattern. This microstrip array antenna can be used for X-band short-range microwave applications.
© 2010 IUP. All Rights Reserved.
Dual Band Microstrip Antennas
-- Kishan Singh, N M Sameena and S N Mulgi
This paper presents a novel design of square microstrip antenna for dual band operation with magnitudes of 6.58%
of lower and 27.53% of upper band. This is achieved by simply doubling the thickness of the substrate of
conventional square microstrip antenna. Triple bands are obtained by embedding U-slot on the radiating patch. Further, the
two upper bands are merged together when U-slot is replaced by inverted L-slot on the square patch and gives 47.71%
of maximum bandwidth of upper band with negligible change in the lower band without affecting the nature
of broadside radiation characteristics. The proposed antennas may find application in radar communication.
© 2010 IUP. All Rights Reserved.
Parametric Methods of Spectral Estimation of MST Radar Data
-- K Nagi Reddy, S Narayana Reddy and A S R Reddy
This paper deals with parametric spectral estimation techniques applied to
Mesosphere-Stratosphere-Troposphere (MST) radar back scattering from the atmosphere. The proposed algorithm estimates the spectrum of a
complex stationary signal using harmonic methods. The performance of this method is investigated for a simulated real
and complex signal. These methods are applied for testing atmospheric data collected at National Atmospheric
Research Laboratory (NARL), Gadanki, India.
© 2010 IUP. All Rights Reserved.
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