Application and design manual for High Performance RF products

design work much easier NXP’s RF Manual – one of the most important reference tools on the market for today’s RF designers – features our complete range of RF products, from low to high power signal conditioning & high speed data converters. What’s new

Novel MMIC design process using waveform engineering

It has always been the case that talented individuals with an innate understanding of their subject have been able to produce works of outstanding performance. The purpose of engineering science is to define ways in which such achievements can be made on a regular,predictable basis with a high degree of confidence in success. Some tools, such as computers, have enabled an increase in speed and accuracy, whilst others have given a dramatic increase in the insight into the operation or behavior of materials; the electron microscope for instance. Still others have enabled the creation of devices on a scale unimaginable to our predecessors, Molecular Beam Epitaxy for example. This work is the product of the availability of an understanding of complex theory on microwave transistor operation, significant increases in mathematical processing and data handling, and the assembly of a ‘tool’ that not only allows the measurement of high frequency waveforms, but their manipulation to simultaneously create the environments envisioned by the design engineer. It extends the operation of previous narrow band active load pull measurement systems to 40GHz and importantly facilitates the design of high efficiency modes at X band. The main tenant of this work is to propose that rather than the linear approach of characterisation, design, test, re-iterate, that has been the standard approach to MMIC design to date, the first three stages should be integrated into a single approach which should obviate the need for design reiteration. The result of this approach should be better performance from amplifier designs, greater probability of success first time, and lower costs through less wafer real estate being consumed and fewer sign ‘spins’

Measurement techniques for the characterization of radio frequency gallium nitride devices and power amplifiers

The rapid growth of mobile telecommunications has fueled the development of the fifth generation (5G) of standards, aiming to achieve high data rates and low latency. These capabilities make use of new regions of spectrum, wider bandwidths and spectrally efficient modulations. The deployment of 5G relies on the development of radio-frequency (RF) technology with increased performance. The broadband operation at high-power and high-frequency conditions is particularly challenging for power amplifiers (PA) in transmission stages, which seek to concurrently maximize linearity and energy efficiency. The properties of Gallium Nitride (GaN) allow the realization of active devices with favorable characteristics in these applications. However, GaN high-electron mobility transistors (HEMTs) suffer from spurious effects such as trapping due to physical defects introduced during the HEMT growth process. Traps dynamically capture and release mobile charges depending on the applied voltages and temperature, negatively affecting the RF PA performance. This work focuses on the development of novel measurement techniques and setups to investigate trapping behavior of GaN HEMTs and PAs. At low-frequency (LF), charge dynamics is analyzed using pulsed current transient characterizations, identifying relevant time constants in state-of-the-art GaN technologies for 5G. Instead, at high-frequency, tailored methods and setups are used in order to measure trapping effects during the operation of HEMTs and PAs in RF modulated conditions. These RF characterizations emulate application-like regimes, possibly involving the control of the device’s output load termination. Therefore, an innovative wideband active load pull (WALP) setup is developed, using the acquisition capabilities of standard vector-network-analyzers. Moreover, the implications of performing error-vector-magnitude characterizations under wideband load pull conditions are studied. Finally, an efficient implementation of a modified-Volterra model for RF PAs is presented, making use of a custom vector-fitting algorithm to simplify the nonlinear memory operators and enable their realization in simulation environments