Post-wall waveguide

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A post-wall waveguide (also known as substrate integrated waveguide (SIW) or a laminated waveguide) is a synthetic rectangular electromagnetic waveguide formed in a dielectric substrate by densely arraying metallized posts or via-holes which connect the upper and lower metal plates of the substrate. The waveguide can be easily fabricated with low-cost and mass-production using through-hole techniques where the post walls consists of via fences. The post-wall waveguide is known to have similar guided wave and mode characteristics to the conventional rectangular waveguide with equivalent guided wavelength.

Waveguide (electromagnetism) waveguide for the transmission of electromagnetic waves; linear structure that conveys electromagnetic waves between its endpoints

In electromagnetics and communications engineering, the term waveguide may refer to any linear structure that conveys electromagnetic waves between its endpoints. However, the original and most common meaning is a hollow metal pipe used to carry radio waves. This type of waveguide is used as a transmission line mostly at microwave frequencies, for such purposes as connecting microwave transmitters and receivers to their antennas, in equipment such as microwave ovens, radar sets, satellite communications, and microwave radio links.

Dielectric electrically poorly conducting or non-conducting, non-metallic substance of which charge carriers are generally not free to move

A dielectric is an electrical insulator that can be polarized by an applied electric field. When a dielectric is placed in an electric field, electric charges do not flow through the material as they do in an electrical conductor but only slightly shift from their average equilibrium positions causing dielectric polarization. Because of dielectric polarization, positive charges are displaced in the direction of the field and negative charges shift in the opposite direction. This creates an internal electric field that reduces the overall field within the dielectric itself. If a dielectric is composed of weakly bonded molecules, those molecules not only become polarized, but also reorient so that their symmetry axes align to the field.

A via or VIA is an electrical connection between layers in a physical electronic circuit that goes through the plane of one or more adjacent layers. To ensure via robustness, IPC sponsored a round-robin exercise that developed a time to failure calculator.

For instance, the equivalent width of a rectangular waveguide compared to a SIW is described in the approximation:

where is the distance between the posts in the post wall, describes the radius, and as well as are the widths of the rectangular waveguide and SIW respectively.

See also

Ke Wu Canadian engineer

Dr. Ke Wu is professor of Electrical Engineering at the Ecole Polytechnique(University of Montreal), and Tier-I Canada Research Chair in Radio-Frequency (RF) and Millimetre-Wave Engineering. He is Director of the Poly-Grames Research Center, and the Founding Director of a Canadian university-industry consortium called Facility for Advanced Millimetre-wave Engineering (FAME) and the Center for Radiofrequency Electronics Research of Quebec. He also holds the first Cheung Kong endowed chair professorship (visiting) at the Southeast University and the first Sir Yue-Kong Pao chair professorship (visiting) at the Ningbo University, China.


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