@article{hicks_yakovlev_steer_2003, title={Aperture-coupled stripline-to-waveguide transitions for spatial power combining}, number={2003 Nov}, journal={Applied Computational Electromagnetics Society Journal}, author={Hicks, C. W. and Yakovlev, A. B. and Steer, M. B.}, year={2003}, month={Nov}, pages={33–40} }
@article{tayag_steer_harvey_yakovlev_davis_2002, title={Spatial power splitting and combining based on the Talbot effect}, volume={12}, ISSN={["1531-1309"]}, DOI={10.1109/7260.975718}, abstractNote={The Talbot effect, a multimode interference phenomenon, is investigated as a technique for combining power from solid-state devices in order to generate higher levels of microwave and millimeter-wave power in a process referred to as quasioptical or spatial power combining. We explore the feasibility of using the Talbot effect to implement a 1 /spl times/ 8 power splitter and an 8 /spl times/ 1 power combiner at 94 GHz. We report the first demonstration of the multimode interface phenomenon in a planar waveguide at 8 GHz.}, number={1}, journal={IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS}, author={Tayag, TJ and Steer, MB and Harvey, JF and Yakovlev, AB and Davis, J}, year={2002}, month={Jan}, pages={9–11} }
@article{yakovlev_ortiz_ozkar_mortazawi_steer_2000, title={A waveguide-based aperture-coupled patch amplifier array - Full-wave system analysis and experimental validation}, volume={48}, ISSN={["0018-9480"]}, DOI={10.1109/22.899032}, abstractNote={In this paper, the full-wave analysis and experimental verification of a waveguide-based aperture-coupled patch amplifier array are presented. The spatial power-combining amplifier array is modeled by the decomposition of the entire system into several electromagnetically coupled modules. This includes a method of moments integral equation formulation of the generalized scattering matrix (GSM) for an N-port waveguide-based patch-to-slot transition; a mode-matching analysis of the GSM for the receiving and transmitting rectangular waveguide tapers; and a finite-element analysis of the waveguide-to-microstrip line junctions. An overall response of the system is obtained by cascading GSMs of electromagnetic structures and the S-parameters of amplifier networks. Numerical and experimental results are presented for the single unit cell and 2/spl times/3 amplifier array operating at X-band. The results are shown for the rectangular aperture-coupled patch array, although the analysis is applicable to structures with arbitrarily shaped planar electric and magnetic surfaces.}, number={12}, journal={IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES}, author={Yakovlev, AB and Ortiz, S and Ozkar, M and Mortazawi, A and Steer, MB}, year={2000}, month={Dec}, pages={2692–2699} }
@article{yakovlev_hanson_2000, title={Mode-transformation and mode-continuation regimes on waveguiding structures}, volume={48}, number={1}, journal={IEEE Transactions on Microwave Theory and Techniques}, author={Yakovlev, A. B. and Hanson, G. W.}, year={2000}, pages={67–75} }
@article{yakovlev_khalil_hicks_mortazawi_steer_2000, title={The generalized scattering matrix of closely spaced strip and slot layers in waveguide}, volume={48}, ISSN={["1557-9670"]}, DOI={10.1109/22.817481}, abstractNote={In this paper, a method-of-moments integral-equation formulation of a generalized scattering matrix (GSM) is presented for the full-wave analysis of interactive planar electric and magnetic discontinuities in waveguide. This was developed to efficiently handle a variety of waveguide-based strip-to-slot transitions, especially on thin substrates. This single matrix formulation replaces the problematic procedure of cascading individual GSM's of an electric (strip) layer, a thin substrate, and a magnetic (slot) layer.}, number={1}, journal={IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES}, author={Yakovlev, AB and Khalil, AI and Hicks, CW and Mortazawi, A and Steer, MB}, year={2000}, month={Jan}, pages={126–137} }
@article{gnilenko_yakovlev_1999, title={Electric dyadic Green's functions for applications to shielded multilayered transmission line problems}, volume={146}, number={2}, journal={IAWA Journal}, author={Gnilenko, A. B. and Yakovlev, A. B.}, year={1999}, pages={111–118} }
@article{hanson_yakovlev_1999, title={Investigation of mode interaction on planar dielectric waveguides with loss and gain}, volume={34}, ISSN={["0048-6604"]}, DOI={10.1029/1999RS900096}, abstractNote={On lossless isotropic planar waveguides the discrete proper modes of propagation form independent transverse electric and transverse magnetic sets such that there is no mode coupling or interaction between modes. In the event of material loss or gain, mode interactions are possible, leading to a complicated spectrum and apparent nonuniqueness of the modes. In this paper we analyze for the first time the cause of these modal interactions by studying the simplest canonical planar waveguide which exhibits these effects, the symmetric‐slab waveguide. We show that mode interactions are due to the migration of complex‐frequency‐plane branch points associated with specific wave phenomena, with varying loss or gain. As these singularities move near the real‐frequency axis they influence the modal behavior for time‐harmonic (real‐valued) frequencies, crossing the real axis at some critical value of loss or gain. It is shown that as time‐harmonic frequency varies, passing above, below, or through these branch points results in different modal behavior. Passing above or below, and near to, the branch point yields mode coupling behavior, while passing through the branch point results in modal degeneracy. The result of this branch point migration is that the association of a particular mode with a certain branch of the dispersion function depends not only on the value of material loss or gain, but also on the order in which physical parameters of the problem are varied. Three different branch point types are identified and discussed, which leads to an understanding of the relevant wave phenomena and to a method for organizing the mode spectrum in a consistent and unique manner. While many of the observations described here are based on careful numerical analysis of the transverse magnetic modes existing on a certain symmetric‐slab waveguide, the described phenomena are reasonably expected to be generally found in other open dielectric waveguiding structures.}, number={6}, journal={RADIO SCIENCE}, author={Hanson, GW and Yakovlev, AB}, year={1999}, pages={1349–1359} }
@article{hanson_yakovlev_1998, title={An analysis of leaky-wave dispersion phenomena in the vicinity of cutoff using complex frequency plane singularities}, volume={33}, ISSN={["0048-6604"]}, DOI={10.1029/98RS01440}, abstractNote={In this paper we analyze characteristics of the dispersion function for leaky‐wave modes in the vicinity of cutoff for several representative waveguiding structures. Our principal purpose is to demonstrate that in the vicinity of leaky‐wave cutoff in open‐boundary waveguides (in the spectral‐gap region), dispersion behavior is controlled by the presence of branch points in the complex frequency plane. A similar situation occurs for the ordinary modes of homogeneously filled, perfefctly conducting cylindrical waveguides. These closed waveguides admit to simple analysis, leading to an explicit dispersion function which indicates frequency domain branch points. For open‐boundary waveguides, the presence of frequency domain branch points is obscured by the necessity of numerically solving an implicit dispersion equation. A set of sufficient conditions is provided here which defines these branch points in a unified manner for both open and closed waveguides. Identification of these points allows for rapid determination of important and interesting regions in both the frequency and wavenumber planes and leads to increased understanding of dispersion behavior, especially in the case of dielectric loss. Examples are shown for several waveguiding geometries to demonstrate the general nature of the presented formulation.}, number={4}, journal={RADIO SCIENCE}, author={Hanson, GW and Yakovlev, AB}, year={1998}, pages={803–819} }