Minimize Risk When Deploying or Updating RF Power Amplifier Test

Keysight Technologies

Minimize Risk When Deploying or Updating RF Power Amplifier Test Systems

Market Trends

Component and semiconductor manufacturing companies who build RF power amplifiers (PAs) and front-end modules (FEMs) for smart mobile devices are challenged to produce these complex products, often in large volumes, for a highly competitive market. These manufacturers are always looking for ways to drive down costs while improving the performance of their devices.

Because the PAs and FEMs must meet tight tolerances and specifications, testing plays a critical role in the manufacturing process. However, testing can become a production bottleneck as PA and FEM designs become more complicated and require an increasing number of tests.

Testing the latest generation of RF PAs and FEMs brings a host of new test requirements:

–Modern designs such as power amplifier duplex (PAD) modules integrate othercomponents such as filters and duplexers, which must be tested along with the PA

–Techniques such as digital pre-distortion (DPD) and envelope tracking (ET) are usedto overcome efficiency issues caused by high peak-to-average ratio modulationformats, and these techniques must be verified

–Higher numbers of frequency bands and modulation formats require additional testconditions.

To achieve greater measurement speed and throughput, many power amplifier manufacturers are evaluating modular test systems, which offer huge speed improvements in an automated test environment. Modular systems not only are fast, but they have the benefit of a small, more flexible instrument form factor that is adaptable to changing technology and provides relief on a crowded production test floor.

The Challenge

Moving to a new test platform involves a certain amount of effort and risk. The new system needs to be more than fast; it needs to deliver accurate, repeatable results and the advanced measurements, test capability, and performance that will meet the needs of a global manufacturer in a fast-paced market.

Evaluating a traditional test system built around benchtop instruments is relatively straightforward—typically the instrument front panels are used to set up the required measurements or some basic command software is generated using a common high level programming tool.

Evaluating a system based on modular instruments is not quite as simple. Developing test code requires low level programming expertise and a deeper understanding of the measurement science than a manufacturer may have in-house. Modular instruments do not have front panels for quick setup and troubleshooting, which can add time to the test development process. The manufacturer faces a sizeable software effort and could spend months or even years evaluating a system configuration that in the end is not suitable for the application.

Power amplifier manufacturers face some additional hurdles to incorporate specialized hardware and measurement techniques such as digital predistortion and envelope tracking into their systems. And once a system configuration has been evaluated and approved, it must then be seamlessly integrated into the overall production test environment, requiring further investment in programming and test application expertise.

The Solution

Keysight Technologies, Inc. has developed the RF PA/FEM Characterization and Test Reference Solution to help PA and FEM manufacturers quickly and cost-effectively evaluate and deploy design validation and production test systems. This market-validated solution for power amplifier testing combines Keysight benchtop, Keysight and non-Keysight PXI hardware, Keysight measurement software, and Keysight test expertise—in the form of optimized configuration, documentation, and programming examples. This helps manufacturers more rapidly configure and evaluate a test system to meet their specific requirements.

Keysight’s application engineers, solution partners, or the manufacturer’s own internal test groups then integrate the new hardware and software configuration into their larger production test system, incorporating additional hardware, test fixtures, and software as needed.

Reference Solution Features

The RF PA/FEM Reference Solution enables rapid, full characterization of power amplifiers and modules such as PAD devices with S-parameter, demodulation, power, adjacent channel power, and harmonic distortion measurements. DPD and envelope-tracking signal generation and analysis are enabled by Keysight’s N7614B Signal Studio for Power Amplifier Test software.

Closed and open loop DPD and envelope tracking measurements can be made in tens of milliseconds with the M9451A PXIe measurement accelerator. The Reference Solution control software enables tight synchronization between the signal source and the arbitrary waveform generator (AWG), resulting in optimal alignment of the input signal and envelope. The RF PA/FEM Reference Solution also includes a Signadyne single-slot, high speed PXI AWG, which supports fast envelope tracking capability while maintaining a small test footprint.

Leading power amplifier manufacturers want to migrate to fast, flexible, modular test systems not only to meet today’s challenges, but also tomorrow’s. Measurement speed and reliability are core requirements for any new test system, and manufacturers generally want a solution as complete and flexible as possible, sourced from a knowledgeable, reliable test vendor.

Manufacturers quickly “get” the potential benefits of Keysight’s proven, measurement-validated PA/FEM Reference Solution designed specifically for their power amplifier test applications—a solution that immediately eliminates the pressure to develop and evaluate a test system in-house, that saves considerable time and effort, and that reduces the risk of implementation error.

Other factors that are important, and which the Keysight PA/FEM Reference Solution addresses, are the time to first measurement when a proposed system configuration is evaluated; the application engineering expertise of the test partner; and the commitment of the test partner to the manufacturer’s success from solution development through operation.