What is the temperature phase stable cable

Time:2014-04-30 23:54   Source:未知    Author:admin   Click:

The main phase characteristic temperature , the temperature stable phase characteristics and temperature phase tracking characteristics ;

Temperature phase change : refers to variations in temperature , Cable RF signal phase changes through a size , which is generally used PPm to indicate that is a relative amount , generally refers to the number of PPM per meter , if you want to base the absolute amount of the use of the formula can.

Temperature stabilization phase: a predetermined value when the temperature change ( usually refers to +50 ° C -10 ° C temperature change ) , the phase change temperature in the range of less than 500PPM, the temperature is generally thought to be stable phase cable .

Temperature phase tracking : that temperature changes , two or more identical issue with Cable phase varies with temperature . For example, while one type of cable in the -10 degrees Celsius to 50 degrees Celsius change , phase tracking can guarantee millionth order .

Phase temperature and temperature stability are relative phase tracking amount due to the size of the cable itself determines the structure and materials used ( the structure of the material between the layers , the medium , and the uniformity of the dielectric material , the production of the inner conductor etc. ) , before making a Cable assembly have been identified , and the effects of these two parameters Cable assembly process of the production process is relatively small .

In our practical use, we tend to be more concerned about the amount of change in the absolute phase of Cable assembly , which is calculated as the amount of change : detφ = φ0 * PPM / 1,000,000

Wherein the absolute phase φ0 Cable assembly length , and this generally refers to a phase length results tested at room temperature ,

φ0 = L * √ E * F * 360 °, where : L is the physical length of the cable ( unit: m ), E is the dielectric constant of the cable dielectric ( dielectric constant is usually PRFE 2.1), F test corresponding frequency ( unit : GHz),

Can generally be calculated as follows :

Φ (20 ℃) ​​= 360 ° * L * / λ

L: Cable Assemblies Length ( m ) What is the temperature phase stable cable

E: permittivity

λ: Wavelength = C / √ E / FC: speed of light ( m / s ) F: Frequency (GHz)

In actual use, the temperature and the temperature of the stationary phase by phase tracking is not equal to the work with the late correction , so there is a temperature change in the requirements of the application must pay attention to the problem of temperature stabilization phase ; in Cable assembly has a plurality of phase reference request phase temperature tracking is a factor that must be considered .

Phase affected by temperature solution: semi-rigid cable generally used for high temperature , cold and other treatment ;