Parallel type substrate integrated waveguide Gunn oscillator

Investigation of SIW‐based planar integrated w‐band low‐phase noise Gunn harmonic oscillator

“…A certain scale of size reduction (70-85% [1][2][3]) can be reached by this method; however, it is restricted to relatively narrow strips and usually suffers from considerable insertion loss due to the vast number of intentional discontinuities along the microstrip. Another concept has been proposed by etching various defects on the ground plane metallization leading to miniaturization on considerable scale (59% [4]); however, such a technique increases the complexity of the fabrication process and can also cause difficulties in terms of electromagnetic compatibility. To date, scores of examples of successful implementation of the slow-wave mode propagation leading to compact hybrid ring circuit solutions (50-96%) through the implementation of artificial transmission lines (ATLs) loaded by singular or multiple stubs have been extensively reported [5][6][7][8][9][10][11][12][13][14][15].…”

Low phase‐noise planar oscillators using high‐Q SIW bandpass filter

“…The oscillator is one of the fundamental components in microwave circuits. In recent years, there have been numerous attempts to reduce the phase noise of oscillators, which have some advantages for low cost and improved reliability [1, 2]. Nevertheless, their phase‐noise characteristics are inferior due to the poor Q factor of the resonator.…”

A 94 GHz low‐cost frequency source using a 47 GHz micromachined air‐cavity oscillator and a doubler

“…However, the size of dielectric resonator is too small to fabricate precisely at millimeter-wave frequencies because the dielectric resonator has a high-dielectric constant. Another method of oscillator stabilization is a substrate integrated cavity scheme, which consists of metalized via-holes made in dielectric substrates [3,4]. This method is useful for lower frequencies because the size and pitch of the via-holes are normally large, which might result in a radiation loss at high-frequency and an inaccurate resonant frequency.…”

“…Several integral equation (IE) methods have been developed to solve these problems [1]. Such as the volume-surface IE (VSIE) [2], the impedance boundary condition (IBC) [3,4], the thin dielectric sheet (TDS) [5], etc.…”