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This article presents the evaluation of using pulsed-radio frequency (RF) signals as multitone phase standards for modulated measurements at millimeter-wave (mm-Wave) bands, offering an alternative phase calibration choice for nonlinear vector network analyzers (NVNAs). Based on the NVNA measurements of two pulsed-RF signals generated by square-wave-driven mixers, a high correlation between magnitude and phase errors of unideal pulsed-RF signals is discovered, and an empirical method is developed to accurately estimate the phase errors according to magnitude-only measurements. To confirm its robustness and key preconditions for wide-range applications, theoretical support and explanation to the empirical method is revealed, in which the dominant waveform distortion of an applicable pulsed-RF signal can be decomposed into modulated perturbations with Sinc-like envelopes. The validity of the proposed empirical method, as well as its application for mm-Wave NVNA phase calibration, is verified by both experimental measurements and simulation results, where an estimation error (or phase calibration error) less than ±2° is demonstrated that is reachable in practice. [ABSTRACT FROM AUTHOR]

We investigated the measurement techniques of the nonlinear vector network analyzer (NVNA) test bench, to fully characterize the nonlinear behavior of radio frequency (RF) power amplifiers (PAs) driven by complex modulated signals. In order to extend the baseband measurements, two kinds of NVNA phase reference approaches are developed as alternative solutions, so that the baseband phase measurements can be achieved with those of modulated components at multiharmonic RF bands. In the first approach, a modulated baseband signal is combined with another modulated RF one to become the desired NVNA phase reference. While as an alternative solution, the second phase reference design is based on a “stepped” multisine, which is stepped through the baseband and each harmonic following the NVNA swept measurements, to achieve stable phase measurements. To validate these proposed NVNA test bench designs, an RF PA, driven by a large-signal long-term evolution-like multisine, was tested and compared with digital real-time oscilloscope measurements. [ABSTRACT FROM PUBLISHER]

Abstract: This paper presents a design methodology of multisine signals, so that they can be used as phase references or standards convenient for modulated measurements. To achieve an extendable measurement bandwidth, the spectrum of each multisine is designed with three successive segments, where the left (lower‐frequency) and right (higher‐frequency) ending ones have the same phase spectra. In this way several multisines, one by one overlapped at the ending segments, can jointly serve as an integrated phase reference/standard signal, which, in theory, has an arbitrarily extendable bandwidth. By the example of “Schroeder” phase relationship, the proposed method is experimentally verified for wideband‐modulated measurements, where the designed multisines are used as the phase references and standards, respectively, of a Nonlinear Vector Network Analyzer test bed. In this work, a phase measurement error less than ±1° is experimentally confirmed for 1,601 t measurements with 160 MHz modulation bandwidth around 2 GHz. [ABSTRACT FROM AUTHOR]