Triple Beat Analysis: What, Why & How?

It isn’t breaking news that RF receiver designs are growing in complexity, making simulations long and challenging. If you were to measure the cross-modulation in the transmit/receive path for cases where two closely-spaced small-signal inputs from a transmitter leaked in to the receiver along with an intended small-signal RF input signal, you would end up using a 4-tone harmonic balance analysis for the same. Well, am sure, you would know this wasn’t going to be easy on your memory and would actually leave your analysis impractical….

What is more likely to work for you is a Triple Beat analysis, which in spite of being a lot faster than the traditional approach, does not compromise on the quality of same results and still uses significantly less memory!

If you do choose to use the Triple Beat analysis, it might also bring in these additional benefits:

1. Accurate Results: Smart harmonic balance makes large-signal analysis more automated and less error-prone. Based on production-proven technology, it is as accurate as 4-tone harmonic balance, provided the circuit is operating in the “weakly nonlinear” input region.
2. Deep integration with Virtuoso® Technology: Easy to simulate many other measurements from a single design cockpit using Virtuoso® Analog Design Environment.
3. Powerful Modeling Technology: Fastest, accurate method to compute small-signal Triple Beat measurements.

The use model of Triple Beat analysis is similar to Rapid IP2/IP3 analysis except that it uses three tones instead of two.

You apply the Local Oscillator (LO) signal in hb, and then use hbac Triple Beat to simulate the three inputs to the receiver. This is a small-signal analysis. So, if the input levels for all three tones do not fall within the small-signal range, the result is likely to be inaccurate because any large-signal effects may not be considered by hbac.

Currently, Triple Beat analysis is only available in the hbac Choosing Analyses form.

For more information on the Triple Beat analysis, you can view the Triple Beat Analysis video on Cadence Online Support. Click the video link now or visit Cadence Online Support and search for the video under Video Library.

Related Documents

• Faster Triple-Beat Analysis for Receiver Design
• Spectre Circuit Simulator and Accelerated Parallel Simulator RF Analysis in ADE Explorer User Guide

For more information on Cadence circuit simulation products and services, visit www.cadence.com.

-Mayank Kumar