Content that is free for public consumption with no subscription.
Reflectometer slide rules were handy for quickly looking up conversions between SWR, return loss, and reflection coefficient. Use this slide rule right on your computer (is this an anachronism?) in any JavaScript enabled web browser!
Tutorial on MIMO (multiple input/multiple output) techniques and how they differ from other multiple access strategies. Charan Langton's tutorials are excellent resources for learning complex communications concepts. The bibliography at the end provides a good starting point for further research as well.
This app note gives an overview of the physical layer (radio) aspects of Long Term Evolution (LTE) plans for cellular systems. It provides a good summary of the important concepts.
In this article, instructor Arturo Mediano shares a tip on how you can use the vector network analyzer to gauge the shielding effectiveness of different materials.
This workbook from the RF Technology Certification program demonstrates how to convert from dBm to milliwatts using approximation techniques without a calculator. An interactive calculator at the end demonstrates the process with values that you can enter yourself to practice.
This in-depth resource provides comprehensive coverage of femtocells and how they integrate with existing 3G and emerging wireless protocols and standards. Femtocells: Design & Application provides a technical roadmap for migrating to femtocell technology, covering network architecture, media protocols, system performance, and security issues. Detailed architectural diagrams illustrate various deployment options. This is a practical guide to the pioneering technology that enables extended indoor service coverage.
Successfully troubleshooting EMI/EMC problems isn't easy. You need time, you need a strategy, and you need to remain calm. Sometimes, you need a special "sixth sense" that only comes from experience because in some cases, your problems aren't even related with the EUT (equipment under test).
Article by instructor Arturo Mediano about near-field scanners.
I love near field probes because they let me "see" magnetic and electric fields with an oscilloscope or with a spectrum analyzer. They let locate sources of emissions in board, cables, and systems. Near-field scanners also let you see emissions, particularly all over a board. That's hard to do with a single probe.