GSM/DCS Dual Antenna Switch Module (ASM)
With continuously decreasing dimensions of modern mobile phones the compact design of all internal modules is an essential development goal. The structure considered is from a dual band phone (GSM 900 MHz + DCS 1800 MHz) which combines a diplexer for both bands and a low pass filter for each band. The device is only 4.5 mm by 3.2 mm and utilises LTCC technology.
Firstly, the diplexer functionality is investigated:
Figure 1: The ASM structure with the relevant ports for the diplexer mode.
In the diplexer port 2 represents the GSM, port 3 the DCS part. The following figures represent the return loss of both modes as well as the transmission to the common port 1. The left graphs show the simulations, the right ones the measurements. Excellent agreement between the results can be observed.
Figure 2: Return loss and transmission of the diplexer GSM part (simulation left, measurement right).
Figure 3: Return loss and transmission of the diplexer DCS part (simulation left, measurement right).
In the following section the both low pass filters for the GSM and the DCS bands are considered. The relevant ports for both modes are shown in the structure.
Figure 4: The ports for the GSM low pass filter in the ASM structure.
Figure 5: Simulation (left) and measurement for the GSM low pass filter.
Figure 6: The ports for the DCS low pass filter in the ASM structure.
Figure 7: Simulation (left) and measurement for the DCS low pass filter.
The copyright for the displayed structure is with "Korea Electronics Technology Institute (KETI), High Frequency Materials Research Center".
CST Article "GSM/DCS Dual Antenna Switch Module (ASM)"
last modified 10. Feb 2012 6:38
printed 10. Feb 2012 6:38, Article ID 127
URL:
All rights reserved.
Without prior written permission of CST, no part of this publication may be
reproduced by any method, be stored or transferred into an electronic data processing system, neither mechanical or by any other method.
Article ID: 127
Last modified: 10. Feb 2012 6:38
Other Articles
Winfried Krämer, Hirschmann Automation and Control GmbH
Hirschmann Automation and Control is one of the leading providers of industrial Ethernet at bitrates up to 10 Gigabit per second. Using CST MWS we have examined signal paths regarding signal quality, crosstalk and EMC related issues and have identified influences of vias, stackup and other parameters affecting the quality of our high speed interfaces. As the measurement of impedance of critical pins in the power delivery system is challenging, a simulation allows us to evaluate the position dependent information. Furthermore, we also succeeded in improving housing design in RF-matters, tag and optimize the “sites of crime”. Using the capabilities of a simulation helps us to fit the “first shot” layout into a demanding environment and also to optimize an existing layout to ensure performance at growing requirements to the designs. Additionally, it gives us a cost and time effective possibility to answer the “what if” – questions and visualize the points of interest helps to generate reliable constrains.
Read full article..
Stefan Prorok, Hamburg University of Technology
We present an overview of our current research activities in silicon photonics and thermal barrier coatings. Doing so, we will comment on how CST Microwave Studio can be used to design strip waveguides, micro ring resonators, as well as 2-D and 3-D photonic crystal structures. Particularly we will concentrate on the discussion of photonic crystal micro cavities which can be used as electro-optic modulators. It will be shown that MWS provides all the functionality to optimize and characterize optical micro cavities. The appearance of resonant modes is adjusted through eigenmode calculation of the photonic crystal waveguide modes. Time domain simulation with discrete port excitation is applied to calculate the intrinsic Q-factor of the cavity. Waveguide ports are used to model experimental conditions of excitation with strip waveguide modes. Field monitors help to understand the mechanism of energy loss from the cavity. The simulation results are compared to measurements on fabricated structures. As possible application we will show a hybrid silicon organic hetero structure cavity for GHz electro-optic modulation.
Read full article..
The telecommunications sector is making great advances aimed at delivering an even stream of high tech devices, covering the significant consumer demands in this sector. EM simulation is increasingly becoming an indispensable tool in the design flow, not only on the antenna level but also on the phone and environmental levels. This article compares simulated results with measurements for several steps in the phone design chain.
Read full article..
This article demonstrates the capabilities for importing the HUGO dataset via the CST STUDIO SUITE™ Voxel Data Interface.
Read full article..
The Bragg Reflector implemented in the coaxial technology is an example for setting up simulations of periodic structures. The simulation is performed with CST MICROWAVE STUDIO® and compared to measurements.
Read full article..