3. Conclusion

Lines or guides are indispensable structures for connecting the electrical devices of a system in general. At high frequencies, however, they no longer constitute ideal connections, but lead to phenomena that degrade system performance: dispersion, conduction and dielectric losses. Numerous developments have been made to minimize these effects and make these structures more compatible with integration. Indeed, the trend is to use increasingly higher frequency bands to increase data rates and find a solution to frequency congestion.

After a review of the phenomenon of propagation in guides and the basic equations, the description of the main structures used was presented. Dispersion and cut-off phenomena were also discussed. Practical formulas for synthesizing and calculating parameters such as loss loss were given.

Certain structures, such...