Sheath wave barrier unit
A sheath wave barrier unit for an outer shielding of a coaxial cable that also has an inner conductor, has two sheath wave barriers that damp or suppress sheath waves that are induced in two series conductor segments of the outer shielding. Each sheath wave barrier forms a resonant oscillating circuit at a predetermined high frequency, with the high frequency being the same for both sheath wave barriers. The sheath wave barrier unit has a shielding device with at least one radial shield by means of which the sheath wave barriers are decoupled from one another. The sheath wave barriers and the shielding device are arranged on a common carrier.
1. A sheath wave barrier unit for an outer shielding of a coaxial cable, said coaxial cable also comprising an inner conductor, said sheath wave barrier unit comprising:
a first sheath wave barrier and a second sheath wave barrier;
said first sheath wave barrier damping sheath waves induced in a first conductor segment of said outer shielding;
said second sheath wave barrier damping sheath waves induced in a second conductor segment of said outer shielding in series with said first conductor segment;
each of said first and second sheath wave barriers forming a resonant circuit at the same predetermined high frequency;
a shielding device having at least one radial shield that decouples said first and second sheath wave barriers from each other; and
a carrier at which said first and second sheath wave barriers and said shielding device are disposed.
2. A sheath wave barrier unit as claimed in claim 1 wherein said shielding device comprises a tangential shield disposed on said radial shield and surrounding said first and second conductor segments and said first and second sheath wave barriers.
3. A sheath wave barrier unit as claimed in claim 2 wherein said tangential shield has opposite ends, and said shielding device comprising annular shields respectively disposed at said opposite ends of said tangential shield and extending from said tangential shield to said outer shielding.
4. A sheath wave barrier unit as claimed in claim 1 wherein each of said first and second sheath wave barriers comprises a capacitor, the respective capacitors being disposed at respective ends of said first and second sheath wave barriers facing away from each other.
5. A sheath wave barrier unit as claimed in claim 4 comprising a tangential shield disposed on said radial shield and surrounding said first and second conductor segments and said first and second sheath wave barriers, and extending over the respective capacitors.
6. A sheath wave barrier unit as claimed in claim 1 wherein said outer shield comprises a plurality of coil windings substantially coinciding with said first and second sheath wave barriers.
7. A sheath wave barrier unit as claimed in claim 1 wherein said first sheath wave barrier is identical to said second sheath wave barrier.
8. A sheath wave barrier unit as claimed in claim 1 wherein said high frequency is greater than 100 MHz.