Pyong K. Park

Shunt/series coupling slot in rectangular waveguides

A shunt/series couplinq slot can be used as an unequal power divider. Characterization by empirical measurement of this shunt/series slot is particularly difficult and time consuming when an odd waveguide size is required. However,this type of slot can be analyzed by the moment method. The theoretical results of this analysis are compared with experimental results.

Low cost planar lens ESA

Rapid beam switching will advance missile seeker capability including forward looking guidance-integrated fusing, and tracking in shorter range. However, the conventional AESA approach is not affordable at the present time. To meet RES needs, we developed a low cost 1D lens ESA with the DARPA FAME contract. The lens ESA is a stack of parallel conducting plates filled with ferroelectric material. We studied the applicability of this technology to a tactical missile seeker. We found that an X-band lens ESA built with current materials can accomplish most mission profiles for tactical missiles, especially for semi-active seekers. The architecture and design of the current lens ESA are presented. The construction including RF feed, impedance matching, prevention of high voltage breakdown, element characterization, and static ESA demonstration are discussed.

Mutual admittance between slots on a plane

The exact expression of the mutual admittance between two slots on a plane involves a quadruple [1] integration. The fact that the Greens function possesses a difference form allows a quadruple integral to be reduced to a double integral. For a narrower slot such as the waveguide fed slot, the mutual admittance expression can be reduced to a single integral instead of a double integral [2] if one ignores the effect of the width. The validity range of the zero width solution and the Illinoiss approximate solution [3] are established by comparing with the exact solution. A flat plate array design process requires a large number of mutual admittance calculations. The above three formulas would greatly reduce the computation effort.