Spurline resonators design and its implementation to microwave oscillators

Abstract

In this article, two compact L‐type spurline and symmetric meander spurline resonators were designed and implemented into low phase‐noise microwave oscillators for X‐band application. These resonators have a bandstop characteristic that can be used in the series feedback oscillator topology. Both of these miniaturized resonators are designed with different spurline structures, the first one being an L‐type spurline and the other one a meander spurline. Both resonators exhibited inherently inductive characteristics and had a loaded stub with capacitive characteristics. The oscillators using the spurline and the symmetric meander spurline resonators show excellent phase‐noise performances of −96.23 dBc/Hz and −104.39 dBc at a 100 kHz offset from the carrier frequency of 9.2 and 9.0 GHz with an output power of 12.47 and 16.42 dBm, respectively. The latter oscillator exhibited better phase‐noise characteristics due to the high Q value of the symmetric meander spurline resonator. The figure of merit of the first oscillator achieved −174, and the latter achieved −181.36. The size of the oscillator is reduced by constructing a parallel combination of the open stub at the source and the DC voltage supply at the drain © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:171–176, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26461

Microwave Tunable Notch Filter Based on Liquid Crystal Using Spiral Spurline Technology

“…Spurline structures are microstrip single‐resonator notch filters which offer a good band stop performance and easiness of manufacture. These structures can be modeled by a parallel resistor‐inductor‐capacitor (RLC) circuit, where the inductance ( L ) and capacitance ( C ) values determine the filter rejection frequency and the resistance ( R ) models the filter losses . Several kinds of spurline structures have been reported: conventional , meander , and spiral .…”

Low phase noise oscillator using a new planar hairpin resonator for X‐band applications

“…The calculated FOM is approximately of À180 dBc/ Hz with dissipated power of 147 mW. The phase noise and the output power of the microwave oscillator using different microstrip resonators like spurline resonator, spiral resonator, planar helical resonator are compared and tabulated as in Table 1 [9][10][11][12]. Among those recently published articles, the microwave oscillator using the new proposed planar resonator exhibited better phase noise characteristics with output power at the similar frequency regime.…”

Microwave oscillator design using folded T‐type slot resonator for X‐band applications

“…Therefore, the folded T‐type slot configuration is a better choice than another spurline or hairpin resonators due to its better Q factor, and the phase noise characteristic of microwave oscillator can be improved. We have already done these works with spurline resonators and its implementation to the microwave oscillators that assisted us to improve the folded resonator structure [2, 6].…”

“…To achieve a low phase noise, a high value resonator‐ Q factor or a loaded Q is required [1]. There are various types of resonators used in oscillators that enable a low phase noise and a high Q value, such as spurline resonators [1–6], hairpin resonators, and dielectric resonators. In the case of a spurline resonator, its Q value is not so high and unstable in high temperature and in the case of hairpin resonator, its Q value is also low, even if it is compact in size, and it is also unstable in high temperature.…”