IEC 61196-1-123:2023

Overview

IEC 61196-1-123:2023 is an international standard published by the International Electrotechnical Commission (IEC) that specifies the electrical test methods for determining the attenuation constant of radiating coaxial communication cables. These cables are designed for wireless communication systems in challenging environments-such as tunnels, railways, highways, subways, and elevators-where conventional antenna transmission is unreliable or impossible.

This standard provides a uniform, precise test procedure to assess the electrical performance of radiating cables, ensuring their suitability and reliability in confined and complex structures. It serves as a critical reference for manufacturers, testing laboratories, and system integrators working with coaxial cables in specialized applications.

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Key Topics

Scope and Purpose

• Defines test methods to measure the attenuation constant of radiating coaxial cables.
• Applies specifically to cables used in environments where wireless signals must be transmitted through confined, obstructed spaces.
• Supports quality assurance and performance verification for radiating cable deployments.

Test Methodology

IEC 61196-1-123 outlines two main measurement methods:

• Free-space method:

  • Cable is laid on non-metallic posts 1.5 m to 2 m high.
  • Measurement either with a Vector Network Analyzer (VNA) or power meter arrangement.
  • Cable length must be at least 50 m or 10 wavelengths of the test frequency, whichever is longer.

• Ground-level method:

  • Cable is placed on non-metallic spacers about 10 cm to 12 cm above concrete floor.
  • Also supports VNA or power meter test setups with similar length requirements.

Measurement Procedures

• Use of a Vector Network Analyzer (VNA) to measure S-parameters and calculate attenuation.
• Use of power meters, an RF continuous wave generator, and power splitters for power measurement techniques.
• Calibration procedures defined to ensure accuracy of the test setup.
• Temperature stabilization and correction methods are provided to normalize attenuation values at a reference temperature of 20 °C.

Data Expression and Reporting

• Attenuation constant is standardized to dB per 100 meters, enabling easy comparison across different cables.
• Temperature corrections use a defined correction factor based on cable materials and insulation type.
• Test reports must include ambient temperature, cable length, and corrected attenuation values.

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Applications

IEC 61196-1-123:2023 is highly relevant for:

• Wireless communication system designers working in tunnels, subways, and confined transportation infrastructure.
• Manufacturers of radiating coaxial cables aiming to verify product performance and comply with international standards.
• Testing laboratories performing certification or quality assurance of coaxial cables used as radiating cables.
• Infrastructure operators ensuring that communication systems deployed in complex, obstructed environments meet attenuation requirements for reliable signal propagation.

This standard helps optimize system design and installation by providing consistent and reliable test methods to evaluate how radiating cables impact signal attenuation in difficult environments.

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Related Standards

• IEC 61196-1: Generic specification including general definitions and requirements for coaxial communication cables.
• IEC 61196-4: Sectional specification dedicated to radiating cables, providing detailed construction and performance criteria.
• IEC 61196-1-113:2018: Electrical test methods for attenuation constant, providing complementary test procedures for general coaxial cables.

These related IEC standards collectively form a comprehensive framework for the specification, testing, and application of coaxial cables in communication systems.

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Keywords: IEC 61196-1-123, radiating coaxial cable test, attenuation constant test, electrical test methods, wireless communication cables, tunnels communication system, coaxial cable standard, attenuation measurement, vector network analyzer, power meter test, cable attenuation correction, coaxial cable quality assurance.