Microwave Engineering Europe - November 2007 - (Page 14)

14 MICROWAVE COMPONENTS — EM TOOLS AXIEM: — High-frequency spiral inductor: current ﬂow for thick metal spiral at 20 GHz. compared to the Accelerator A30, the D30 comes into its own as soon as a problem’s size exceeds 10 million mesh nodes. The maximum model size of realistic 3D models that can be tackled with the D30 is about 50 million mesh nodes. Comparisons with standard FDTD methods have shown that PBA effectively reduces the number of mesh nodes necessary for a simulation. This means that in order to reach a similar level of accuracy, an FDTD model can easily exceed 1 billion mesh nodes, a factor 20 more than the PBA model. “Accelerating a slow solver will make it less slow, but never fast. On the other hand, accelerating the fastest available Time Domain solver by a factor 12 can provide an enormous advantage when addressing very complex models, such as complete handsets, cars, or complex boards,” commented Dr. Peter Thoma, Managing Director, R&D, CST. A gridless approach to EM Applied Wave Research, on the other hand, has taken a different approach with its recently launched AXIEM™ EM design software. This tool delivers EM analysis as a true upfront design technology, where it beneﬁts designers most by helping to diagnose issues early, thereby signiﬁcantly shortening the design process. The solver was developed speciﬁcally for 3D planar applications such as RF printed circuit boards (PCBs) and modules, low temperature co-ﬁred ceramic (LTCC), monolithic microwave integrated circuit (MMIC), and RFIC designs. AXIEM is an open boundary, non-gridded, method-of-moments (MoM) solver that supports true thick metal in layered dielectric media. Furthermore, it leverages the most recent advancements in EM solver and meshing algorithms, as well as computer architecture, to deliver speed and accuracy of results that become even more necessary as the design complexity grows and the number of unknowns increases. The solver algorithm within AXIEM was expressly pioneered to overcome limitations of existing 3D planar formulations that rely on the Sommerfeld (or similar) integral for delivering speed of simulation yet at the cost of accuracy and dynamic range. This methodology is unique to AWR and a proprietary technique that is best-described as similar to the fast multipole method, yet adapted for full-wave analysis. As such, the solver algorithm scales on the order of N log(N) as opposed to N3 (the case for most existing MoM products). The product’s solver technology also enables the user to accurately and robustly simulate to DC, which is essential for obtaining the right bias conditions and setting the DC operating points for active structures. The integrity of these broadband results mitigate any design hiccups that may be associated with using the “DC to daylight” results in a subsequent harmonic balance or transient simulation such as those integrated within AWR’s design environment. Additionally AXIEM boasts the inclusion of auto-calibrated internal ports, which maintain their own current return path with relatively low error. These ports eliminate the usual tricks associated with other EM products that require manual de-embedding or an explicit path to a sidewall (i.e., edge ports), and are the ideal excitation for complex structures such as PCBs with many surfacemount pads. Advanced hybrid meshing technology automatically fractures structures with triangular and rectangular elements and is optimized to maximize accuracy with minimal unknowns. This heuristic approach extends the capacity reach of the solver above and beyond traditional single element approaches and likewise makes it an excellent EM tool for signal integrity analysis of large RF PCB designs. The meshing algorithm additionally supports “thick metal,” in that it creates 3D meshes of extruded planar geometries, correctly accounting for all x, y, and z directed currents on all surfaces. This thick metal capability is a prerequisite for successful design of 90 nm and 65 nm RF CMOS problems, where line thickness is often in parity (1:1 ratio) with line widths. Similarly, thick metal support is further required to correctly characterize silicon spiral inductors as well as very large designs like complete GaAs MMICs. Design ﬂow AXIEM as a stand-alone EM solver is a powerful addition to any designer’s set of tools. A key value of the solver, however, lies in its integration into the overall AWR design ﬂow. The solver is seamlessly tied to circuit and system simulation, layout, and veriﬁcation through the proprietary AWR uniﬁed data model (UDM). The UDM provides features such as extraction directly from simulation without having to perform explicit layout and EM setup steps, thereby incorporating EM directly into circuit simulation. The key idea behind UDM is that a change made by one part of the software is immediately available to other parts of the software through a shared data element. For example, a circuit element represented by a set of data is available to all programs in the suite making design and layout concurrent. As opposed to other systems, UDM ensures that the design ﬂow is more network like (or concurrent) as opposed to being linear. Company Information Agilent Technologies www.agilent.com Computer Simulation Technology www.cst.com Applied Wave Research, Inc. www.appwave.com Microwave Engineering Europe ● November 2007 ● www.mwee.com 013_014_MWEE.indd 14 26/10/07 16:27:48 http://www.agilent.com http://www.cst.com http://www.appwave.com http://www.mwee.com

Table of Contents Feed for the Digital Edition of Microwave Engineering Europe - November 2007

Microwave Engineering Europe - November 2007 Contents News Comment Metamaterials: Metamaterials Tackle Communications Wavelengths Microwave Components — EM tools: Microwave Component Design Easier With New EM and EDA Tools Cover Feature: RF Testing for OFDMA in LTE Base-Stations Startup Eyes Battery-Free Wireless Sensor Nets High-speed ADC Technology Paves the Way for Software Defined Radios Planning a WiMAX network: Maximising the ROI by Using Advanced Optimisation Tools Transporting Video Over Wireless Networks Ultrawideband Under the Gun Specifying the Proper SAW Filter Products Product Feature: RF Test Solution Supports Emerging 4x4 MIMO as Well as Multiple Commercial Standards Calendar

Microwave Engineering Europe - November 2007

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.