Mitigating Receiver Desensitization through System-level Simulation
(Room 209)
17 Oct 18
3:10 PM
-
3:50 PM
As the “Internet of Things” takes hold, so does the need for thorough system planning and integration of consumer electronics. The trend in increasing data handling and smaller product size particularly underscores the need for a comprehensive understanding of unintentional emissions as signal sources manifest themselves as potential radio frequency interference (RFI). Simulation provides an efficient means of, not only exposing, but mitigating issues early in the design stage. In this workshop we introduce a workflow that allows engineers the ability to predict receiver desensitization before the product is built. By combining the necessary steps of PCB model preparation, digital signal characterization, electromagnetics simulation, and system-level RFI analysis, attendees will witness a fast and efficient process for interference-free design that can be applied to any product. While any number of applications are possible, our example uses a controller-to-RAM write state as the aggressor source to a Bluetooth receiver, co-located on a wireless device. Using third party models (circuit board/stackup, IBIS signal sources, chip antenna) along with standards-based receiver susceptibility models, we demonstrate an accurate and realistic simulation flow that exposes interference sources. By using receiver “desense” as the driving design metric, we demonstrate two very different approaches to mitigation. The first focuses on improved isolation between aggressor pins and the Bluetooth antenna, which is accomplished through shielding. The second demonstrates how considerations in signaling and data rate is also a crucial factor in avoiding desense. Through this workshop, attendees will gain practical insight on how to best apply a comprehensive simulation workflow to their products and speed time to market.