White Papers

SISO to MIMO: Moving Communications from Single-Input

Mark Elo, Marketing Director of RF Products, Keithley Instruments

De-mystifying Single Carrier FDMA: The New LTE Uplink

This article focuses on the physical layer (“Layer 1”) characteristics of the LTE uplink, describing the new Single-Carrier Frequency Division Multiple Access (SC-FDMA) transmission scheme and some of the measurements associated with it. Understanding the details of this new transmission scheme and measurements is a vital step towards developing LTE UE designs and getting them to market.

Orthogonal Frequency Division Multiplexing

Orthogonal frequency division multiplexing (OFDM) is a form of digital modulation used in a wide array of communications systems. This paper will explain what OFDM is, why it’s important, where it’s used, and what test instrumentation is required to maintain it.

RF Wafer Testing: An Acute Need, and Now Practical

Carl Scharrer, Keithley Instruments, Inc. RF Tests Becoming Indispensable

Software-defined Radio: The next wave in RF test instrumentation

Michael Millhaem, Principal RF Application Engineer Keithley Instruments, Inc. Test equipment manufacturers are constantly challenged to develop new solutions for testing their customers’ latest devices, but they’ve traditionally developed specialized hardware to meet this challenge....

Unraveling Modulation Quality in Mobile WiMAX™ Uplink and Downlink with Multiple Zones and Bursts

This clearly written and informative technical paper examines the WiMAX frame structure, permutation zones and bursts. To illustrate radio complexity and familiarize the reader with digital demodulation tools, the example given in this paper focuses solely on demodulation measurements of a Mobile WiMAX signal with data bursts. Selection of a map file, display and analysis of all data bursts in the map are among the topics presented in this paper. Additionally, the paper discusses how to perform modulation quality measurements on the uplink signal as well.

3GPP FDD and LTE Multicell and Multi-UE Scenarios with the R&S SMU200A Signal Generator

This application note describes how to set up 3GPP FDD and LTE multicell and multi-UE scenarios with the R&S®SMU200A with a focus on routing and leveling of the baseband signals. Furthermore, it describes in detail how to determine the correct AWGN settings, i.e. how to calculate the required signal-to-noise ratio for the various scenarios.

Head to Head: NI PXIe-5665 Versus Traditional Boxed Instruments

This paper discusses the setup details for the demo shown in this video Head to Head: NI 5665 vs. Traditional Boxed Instruments. The demo compares the performance and speed of the NI PXIe-5665 with the Agilent PXA. Rather than comparing the datasheet specifications of both instruments, this video compares the two instruments while performing real- world test scenarios.