Two-slot coiled coaxial cable resonator: reaching critical coupling at a reduced number of coils.

Gerald Hefferman,Tao Wei,Zhen Chen

doi:10.1063/1.4901593

Gerald Hefferman, Tao Wei + Show 1 more

Open Access

https://doi.org/10.1063/1.4901593

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Abstract

This paper reports the experimental demonstration of a coiled coaxial cable resonator capable of meeting the critical coupling condition using a reduced number of coils relative to previously reported coiled resonators. By introducing a second slot along the length of the device, a two-slot coiled coaxial cable resonator was fabricated and critical coupling observed at 22 turns. An additional device with one-slot, but otherwise identically constructed, was also fabricated. After 44 turns, the one-slot device had yet to reach critical coupling. An ultrahigh signal-to-noise ratio (greater than 70 dB) was observed at critical coupling of the two-slot device. This reduction in number of slots necessary to reach critical coupling, and the corresponding reduction of physical length of the device, makes this demonstration of the control of critical coupling a potentially important step towards the successful application of coiled coaxial cable resonators to microwave communication and robust sensing applications.

Highlights

Coaxial cable and optical fiber are two well-understood and ubiquitously utilized methods of guiding electromagnetic waves for telecommunication
Electronic mail: wei@ele.uri.edu This paper reports the experimental demonstration of a coiled coaxial cable resonator capable of meeting the critical coupling condition using a reduced number of coils relative to previously reported coiled resonators
By adopting a structure similar to a fiber Bragg grating (FBG), coaxial cable Bragg gratings (CCBG) can be constructed with many of the same physical characteristics as their optical counterparts, allowing for distributed strain and temperature sensing along the cable length, while avoiding problems of fragility inherent in optical fiber systems

Summary

INTRODUCTION

Coaxial cable and optical fiber are two well-understood and ubiquitously utilized methods of guiding electromagnetic waves for telecommunication. While the overall size reduction from a CCCR over a CCBG is considerable, a reduction in the number of coils necessary to reach critical coupling, and overall length, will confer significant additional advantages to current CCCR technology Chief among these benefits are reduced power loss per device, which allows a larger number of resonators to be multiplexed in series along a single cable, and the increased ease with which individual devices can be integrated into microwave communication systems or embedded within larger structures for sensing applications. These are important traits in structural health monitoring, an area where robust strain and temperature sensors would be advantageous. . Simulation data using a previously reported electromagnetic model for a CCCR device are in close agreement with experimentally observed device behavior

EXPERIMENTAL RESULTS

THEORECTICAL MODELING AND SIMULATION RESULTS

CONCLUSIONS AND DISCUSSION