Double Functionality Concurrent Dual-Band Self-Oscillating Mixer

2022 52nd European Microwave Conference (EuMC)

et al. 2022

This work presents a self-oscillating mixer (SOM) based on a slow-wave structure for phase-noise reduction. Emphasis is placed on the analysis/optimization methods, which include aspects such as conversion gain, nonlinear distortion, and operation boundaries. In a first stage, the parameters of the slowwave structure are optimized to obtain a low phase-noise spectral density. As an example, a structure based on a unit cell containing a Schiffman section is considered. Then, the SOM behavior is addressed through an analytical model that should enable an understanding of its main operation characteristics. A practical FET-based circuit at 2.3 GHz is simulated with some novel harmonic-balance techniques and experimentally characterized.

Section: Introductionmentioning

confidence: 99%

Analysis of a self-oscillating mixer based on a slow-wave structure

Pontón

Ramírez

2022 52nd European Microwave Conference (EuMC)

et al. 2022

“…Despite their demonstrated usefulness, the operation of modulated injection-locked oscillators is complex and susceptible at exhibiting a variety of dynamical effects. The work [3] presented an analysis of the boundaries between zero-IF and heterodyne SOM operation in terms of the input frequency and power, as well as an analysis of possible instantaneous unlocking under amplitude modulations. However, other distortion mechanisms associated with their oscillatory nature have not yet been investigated.…”

Section: Introductionmentioning

confidence: 99%

“…Now a practical zero-IF SOM at 790 MHz shown in Fig.3, based on the transistor ATF34143, will be considered. In view of the above results, the element values were optimized to avoid any extremes in the curve providing the DC signal versus 𝜔 (Fig.4), obtained with harmonic balance (HB)[3]. The boundaries of the locking band are given by the turning-point bifurcations T 1 and T 2[4], and the stable section is the lower one.…”

mentioning

confidence: 99%

Analysis of noise and dynamical effects in zero-IF self-oscillating mixers

Pontón

2021 IEEE MTT-S International Microwave Symposium (IMS)

Herrera

et al. 2021

Zero-IF self-oscillating mixers (SOMs), based on injection locking, enable a compact direct frequency conversion and substantially mitigate the phase noise problem of heterodyne SOMs. Despite these advantages, their operation is complex and susceptible to exhibit a variety of dynamical effects. Here the need for an optimum selection of the operation point in the static injection-locked curve is demonstrated, as well as the inability of the oscillator to follow the variations of the input signal from a certain modulation frequency. Then a noise analysis of the downconverted signal is presented, based on a conversion-matrix formalism applied to a semi-analytical formulation.

“…As a significant extension of the Zero-IF SOM concept, Burasa et al [4] proposed a source-less transmitter-receiver system in which multiple Zero-IF SOMs receive and demodulate multiple independent data streams through a direct frequency conversion to baseband. More recently, and considering the increasing demand of multiband wireless systems, the works [5], [6] proposed a concurrent dual-band Zero-IF SOM that, making use of a stepped impedance ring-shape resonator [7], enables a simultaneous compact direct-frequency conversion in two different frequency bands. In addition, Pontón et al [5], [6] presented an investigation of the stability boundaries of the Zero-IF SOM and its small-signal gain, as well as a strategy to prevent any instantaneous unlocking through a suitable selection of the operation point.…”

mentioning

confidence: 99%

“…More recently, and considering the increasing demand of multiband wireless systems, the works [5], [6] proposed a concurrent dual-band Zero-IF SOM that, making use of a stepped impedance ring-shape resonator [7], enables a simultaneous compact direct-frequency conversion in two different frequency bands. In addition, Pontón et al [5], [6] presented an investigation of the stability boundaries of the Zero-IF SOM and its small-signal gain, as well as a strategy to prevent any instantaneous unlocking through a suitable selection of the operation point. Further theoretical studies of the general performance of Zero-IF SOMs have been carried out in [8], which analyzes their main distortion mechanisms and noise behavior.…”

mentioning

confidence: 99%

Wireless Injection Locking of Zero-IF Self-Oscillating Mixers

Pontón¹,

IEEE Trans. Microwave Theory Techn.

Herrera

et al. 2022

Self Cite

The recently introduced Zero-IF self-oscillating mixers (SOMs) enable a direct frequency conversion, of interest for the implementation of compact and low consumption radio frequency identification (RFID) tags, among other applications. In previous works, the Zero-IF SOM is placed in only one of the terminals of the wireless link, the other one being based on a conventional scheme. In this article, a system made up of two wirelessly locked Zero-IF SOMs, operating as a frequency upconverter and downconverter, will be analyzed to evaluate its potential for low-cost short-range communications. A complete formulation describing the system under antenna and propagation effects will be presented, which, as a particular case, is able to predict the behavior of the previously proposed Zero-IF SOM, locked by an independent signal. The formulation based on oscillator models extracted from harmonic balance allows deriving design criteria for an optimum and robust performance and can predict the maximum communication range, as well as the stability properties and phase-noise behavior. The operation under modulated conditions is analyzed with a novel envelopetransient formulation, accounting for the time differentiation caused by the propagation effects. The methods have been applied to a system of two Zero-IF SOMs operating at 900 MHz.