Out in Front: December 21, 1995

Recognizing the need for RF analysis during the design of wireless-communication and other high-frequency systems, two companies have recently announced high-frequency EDA tools. Cadence, a well-known name in IC and pc-board EDA tools, has introduced SpectreRF. When integrated with Spectre, Cadence’s Spice-based simulator, the combination analyzes low-frequency analog/mixed-signal, and RF designs using the same netlists and nonlinear models. SpectreRF uses a set of time-domain simulation algorithms to analyze linear and nonlinear circuits, including strongly nonlinear circuits, such as switching mixers and ring oscillators, with as many as 1000 transistors. According to Cadence, SpectreRF simulates these circuits orders of magnitudes faster than Spice transient analyses. The tool also simulates large and nonlinear circuits that harmonic-balance analysis does not effectively handle.

SpectreRF includes a Fourier analysis mode for direct evaluation of Fourier transforms and noise-analysis capability for studying frequency-translation effects in mixers and similar circuits. Cadence offers SpectreRF, which runs on Unix platforms, as an option to Spectre and is available now for RF IC design. The tool will be available in the second quarter for RF pc-board and multichip-module design. SpectreRF costs $15,000, and Spectre costs $30,000.

Another company, Ansoft, has added Maxwell Strata to its suite of electromagnetic-field-simulation tools. Maxwell Strata solves s-, y-, and z-parameter problems and lets you feed the results to other high-frequency EDA tools, such as Super-Compact from Compact Software and Touchstone and Libra from HP EEsof. Maxwell Strata also calculates radiation effects for 2-, 2.5-, and true 3-D traces and structures, such as circular spirals and tapered vias. The traces and structures can lie either on or within layered dielectric substrates. Maxwell Strata simulates complex-RF and monolithic-microwave-IC designs, including complex antenna geometries. For antennae, the tool calculates gain, directivity, efficiency, input impedance, and beam width. Maxwell Strata also provides a variety of mechanisms for viewing the results of a simulation, including current- and field-distribution plots, Smith charts, and far-field plots. Maxwell Strata runs on Unix workstations and costs $29,900 separately or $19,900 with any other Ansoft product.   --by Jim Lipman

Ansoft Corp, Pittsburgh, PA. (412) 261-3200.
Cadence Design Systems, San Jose, CA. (408) 943-1234.