1 Scope
This standard specifies the technical requirements and measurement methods for the shielding performance of RF coaxial cables in cable television systems. Any equivalent measurement method that can ensure the same measurement uncertainty can also be used. In case of dispute, this standard shall prevail. This standard is applicable to the detection and evaluation of the shielding performance of RF coaxial cables in cable television systems. The technical requirements and measurement methods for shielding effectiveness are limited to RF coaxial cables in cable television systems that use braided outer conductors. The production and application of RF coaxial cables in cable television systems should comply with this standard
2 Normative References
The clauses in the following documents become clauses of this standard through reference in this standard.
. For dated reference documents, all subsequent amendments (excluding corrected content) or revisions are not applicable to this standard. However, parties to agreements based on this standard are encouraged to study whether the latest versions of these documents can be used. For undated references, the latest version applies to this standardGY/T 135-1998
Technical Conditions and Measurement Methods for Physical Foamed Polyethylene Insulated Coaxial Cables in Cable Television Systems
IPS-TP-403B1
Method for Measuring Coaxial Cable Shielding Effectiveness Using GTEM Cell
3 Terms and Definitions
The following terms and definitions apply to this standard. 3.1
The GTEM cell, also known as the GHz transverse electromagnetic cell, is an asymmetric transmission line system that can generate stable and uniform electromagnetic fields. 3.2
Shielding coupling loss (CL)
The decibel difference between the input power of the GTEM cell and the coupling power of the tested object.
. 3.3Shielding effectiveness (SE)
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