Characterization of RF Micro-Coaxial Cable Insertion Loss Degradation
RF micro-coaxial insertion loss escalates through skin-depth resistance, dielectric loss tangent shifts, mechanical flex displacement, and atmospheric oxidation.
Thermal Coefficient of Resistance
Meaning
Material properties represent the predictable change in electrical resistance of a conductor as its temperature fluctuates. The thermal coefficient of resistance defines the rate at which the ohms increase or decrease per degree of temperature change. It is usually positive for metals, meaning they become more resistive as they get hotter.
This value is expressed in parts per million per degree Celsius.
Linear Relationship
Most conductors follow a consistent pattern within the operating range of standard electronics. The thermal coefficient of resistance allows for the calculation of how a resistor or a trace will behave in a desert or an arctic environment. This predictability is necessary for sensors that rely on precise voltage levels.
Measurement Reference
Standards organizations define a base temperature, often twenty degrees Celsius, for comparing materials. When a device warms up during operation, the thermal coefficient of resistance causes a drift in the performance of the analog circuits. Engineers use this data to select materials that remain stable under the heat of a processor.
Component Accuracy
Precision resistors are built with alloys that have a very low thermal coefficient of resistance. These parts ensure that a timing circuit or a power regulator does not change its output as the internal temperature of the enclosure rises. Choosing the right material prevents the need for complex software compensation in the device firmware.
In high accuracy measurement tools, the stability of these resistors determines the overall precision of the instrument over years of field use.