Other

Northeastern University

Zeji Gu

Paul J Wang

Carey M Rappaport

A non-reflective ring topology MPNT switching device comprises at least two poles, at least four throws, plural main switches, and plural bridge switches. The bridge switches enable all throws to be non-reflective throughout a wide frequency range. Each main switch is connected between one of the poles and one of the throws. Each bridge switch is connected between two of the throws, and each throw is connected to at least M+1 of the bridge switches, M being the pole count. In operation, each of M of the main switches has a first (ON) state and is connected to one of M active throws. For each active throw, each bridge switch connected to the active throw has a second (OFF) state. For each non-active throw, one bridge switch connected to the non-active throw has the first (ON) state and each other connected bridge switch has the second (OFF) state.

Non-reflective MPNT switch

A high isolation electronic multiple pole multiple throw (MPNT) switching device is formed as a ring circuit that includes plural poles, plural throws, plural series switches and plural means for shunting. Each series switch receives a control signal, and each means for shunting receives shunt control signals. In one aspect, the shunt control signals include control signals received by distant series switches. In another aspect, the shunt control signals include control signals received by adjacent series switches. In another aspect, the shunt control signals include signals complementary to signals received by adjacent series switches. In another aspect, the shunt control signals include pole DC potentials or throw DC potentials. In another aspect, a switching device may operate in multiple transmission mode or multiple input multiple output (MIMO) mode. The MPNT switching device provides low insertion loss and high isolation at a wide range of frequencies.

High isolation electronic multiple pole multiple throw switch

A catheter-based microwave antenna cardiac ablation applicator has been developed which unlike previously-developed ablation catheters, forms a wide aperture that produces a large heating pattern. The antenna comprises a spiral antenna connected to the center conductor of a coaxial line, and which is insulated from blood and tissue by a non-conductive fluid filled balloon. The antenna can be furled inside a catheter for transluminal guiding. Once in place at the cardiac target, the balloon is inflated, and the coiled spiral antenna is ejected into the inflated balloon. The wide aperture antenna generates a ring-shaped power pattern. The heat generated from this deposited power is conducted through a volume larger than the spiral diameter, ablating diseased tissue. The resultant lesion profile is both wider and deeper than that of either conventionally-used RF catheter-based ablation electrodes, or that of other microwave applicators, and provides greater heating accuracy and controllability.

Growing community of inventors

Lexington, MA, United States of America

Zeji Gu