Power Amplifier Characterization Essentials

5G frequency range 2 (FR2) implementation demands revolutionary transformation in communication technology. As a result, the wireless communications industry’s emphasis on system integration, power efficiency, and device reliability continues to grow. Mission-critical requirements for a complete 5G infrastructure, notably network densification and rapidly growing consumer demand for electronic and electrified products, stress the need for faster development of highly integrated, reliable radio frequency (RF) devices.

An essential component in modern RF communication chains is the power amplifier (PA). A critical determining factor of transmission quality and battery life, PAs provide needed power to antennas. To satisfy 5G demands, designers need to optimize PA performance. However, the millimeter-wave (mmWave) carrier frequencies, wide bandwidth signals, and complex modulation schemes required to implement 5G impose stringent component error vector magnitude (EVM) qualifications. Designers face increasing challenges in generating accurate device models, minimizing design cycles, and certifying a device’s 5G conformance with a traditional EVM measurement vector signal analyzer (VSA) setup.

Typically, designers conduct nonlinear PA measurements in the time domain using a VSA and vector signal generator (VSG) in what is known as the VSA method. However, Keysight’s evolved frequency domain characterization method, called vector component analysis (VCA), uses a vector network analyzer (VNA) and modulation distortion software application. This method improves access to and accuracy of figures of merit (FOM).

This white paper examines the importance of power amplifier nonlinear characterization, time domain versus frequency domain characterization measurements, and three key measurements using VCA.