N/E9055EM0E Power Amplifier Test Application

Key Features

• Characterize PA (Power Amplifier) with Pre-distortion applied in RF and millimeter wave, with simple and integrated multi-touch user interface

• Provide smart link for automated signal generator closed loop control with power servo to auto-adjust PA output power

• Extracts DPD model and apply Pre-distortion to linearize PA output with supported DPD model as Look-up table (LUT), Volterra Series, Memory Polynomial, Iterative Learning Control (ILC)

• Support user-defined DPD models with MATLAB scripts • Show both Pre-DPD and Post-DPD measurement results in one screen, for ease of comparison. Easily switch between Pre-DPD and Post-DPD results

• Support PA measurements with AM / AM, AM / PM, ACP, Delta EVM, Demod EVM (5G NR FDD or TDD,  LTE-FDD 802.11ac/ax/be), Power vs Demod EVM

• Supports multi-carrier measurements to show EVM results in single screen

• Support waveform processing with crest factor reduction using clipping and filtering or peak cancellation methods

• Use embedded DPD (Look-Up-Table or Memory Polynomial) function of the M9384B or M9484C VXG, so it can avoid downloading Pre-distorted waveform for each DPD iteration, which can improve measurement speed

• Support frequency up to 50 GHz with 2 GHz bandwidth with N9042B UXA and M9384B or M9484C VXG

• Support the burst shape & mask formation to reconstruct the reference waveform and its mask signals for users to evaluate the impact of power support of PA on EVM readouts

• Support M9484B VXG with 2-channel, or PXI VXT and AWG for PA Envelope Tracking (ET) measurement

Power Amplifier Measurement Application

Modern mobile communications, such as 5G NR and WLAN place new demands on linearity, bandwidth and power consumption in wireless components, mobile terminals, or base stations. One of the most nonlinear components is the PA (Power Amplifier). The design of the power amplifier must allow it to:

• Increase spectral efficiency

• Reduce distortion and non-linearity

N9055EM0E Power Amplifier measurement application is an integrated PA testing system mainly targeting 5G NR, WLAN, or other wideband PA test scenarios. N9055EM0E is running inside Keysight Xseries Signal Analyzers which can connect Keysight Signal Generators for signal generation to make both Pre-DPD and Post-DPD PA measurements as the typical measurements shown in the right table.

Digital Pre-Distortion Technology

Power amplifiers with high PAPR (Peak to Average Power Ratio) signals can create non-linearity problems. When a high-power signal is applied to the PA input, the PA can’t linearly amplify the signal, possibly resulting gain saturation and distortion, and ultimately leading to signal quality degradation, such as worse ACP and EVM. DPD technology can be used to compensate for the non-linear behavior of the PA. DPD applies “inverse” distortion to the PA input signal to cancel the distortion generated by the PA. There are several types of DPD methods, including memoryless and memory, which convey the memory effect on a PA. N9055EM0E supports the following methods:

• Look-up table

• Volterra series

• Memory polynomial

• Iterative Learning Control (ILC)

• User-defined DPD model with MATLAB scripts