From Bob Helsel, Editor of the PXI Newsletter:

Welcome to the January edition of the PXI Newsletter.  Our intent is to educate and inform you about how the PXI standard is being used in modular test systems for a wide variety of industries.

Our main article this month, Power Amplifier Testing for 802.11AC, examines the demands that the latest 802.11ac WLAN standard places upon the design validation, characterization and testing of power amplifiers for 802.11ac.

Our second article, Do Modular Instruments Have Any Measurement Limitations?, explores this common question to instrument vendors with regard to PXI.

In the New PXI Products section, we are showcasing PXI products recently released by members of the PXI Systems Alliance.

Thanks to National Instruments, our sponsor for this month's issue.

Visit http://www.pxisa.org for more information.

Main Article

Power Amplifier Testing for 802.11AC

by  Christopher Ziomek, ZTEC Instruments

Introduction
The first Wireless LAN (WLAN) standards were used primarily to provide low data rate wireless connectivity to a wired broadband connection for web browsing and email. Over time, new 802.11 wireless protocols were adopted to offer higher data rates for new applications. Table 1 shows the progression of the 802.11 WLAN standards.

The latest 802.11ac WLAN standard, which is still in draft format, will achieve up to 867 Mbps data rate over a single RF channel, and up to 6.93 Gbps using MIMO channels. These high 802.11ac data rates are accomplished by extending the 802.11n standard with more instantaneous bandwidth (up to 160 MHz), more MIMO channels (up to 8), and higher density modulation constellations (up to 256QAM). Within this paper, we examine the demands that these new requirements place upon the design validation, characterization and testing of power amplifiers for 802.11ac.

Read more >>

Second Article

Do Modular Instruments
Have Any Measurement Limitations?

by Larry Desjardin, Modular Methods

Perhaps the most common question asked of me from equipment vendors or users is to identify the measurement limits of modular standards like PXI, VXI, or AXIe.  Is there some fundamental frequency limit, parametric accuracy limit, or other measurement limitation that retains traditional instruments as the only solution for a particular application?

Let’s put aside two pragmatic factors that do impact the choice between modular and traditional instrumentation: availability and use model. This article will focus exclusively on measurement capability, and will look at PXI in particular.

Are there measurement limitations to modular instruments? My short answer is “very few, and becoming fewer.”  

Let’s see why.  An open modular standard like PXI is a set of rules that describes a module’s mechanical dimensions, electrical and power interfaces, and communication bus.  Do these restrict the type of instruments that can be designed?  Let’s look at each aspect.

Read more >>

Thanks to all our readers.
Bob Helsel, Editor
www.pxisa.org

New PXI Products