The Power Capacity of RF Coaxial Connectors

The power capacity of RF coaxial connectors is an important link in the standard of evaluating the quality of RF coaxial connectors. So how much do you know about the power capacity of RF coaxial connectors? A detailed introduction to the power capacity of RF coaxial connectors will be given in the following passage.

The power capacity of RF coaxial connectors is a very complex problem, which is completely different from the power transmission in DC or low frequency. There are many factors that can affect the power capacity.

• Pinhole size: the pinhole size is related to the current capacity of the connector and directly related to the power.

• VSWR: The reflected wave takes up the channel capacity space, which reduces the transmission power capacity.

• Insertion loss: There is a difference between the input and output power because of the insertion loss.

• Air pressure (Altitude): The change of air pressure leads to the change of the dielectric constant of air section, and the gas is easy to ionize then the corona will be produced at low pressure. The higher the altitude is, the lower the air pressure is and the smaller the power capacity is.

• Contact resistance: The existence of contact resistance will cause contact heating, which makes it difficult to transmit high-power microwave signals.

• The influence of frequency: The change of transmission signal frequency directly leads to the change of insertion loss and VSWR, which affects the transmission power capacity. There will also be skin effect.

Since the above reasons are uncertain factors, the power capacity value index of the connectors is generally not calibrated (you will find later that the theoretical value is too high and far beyond the scope of use). The power capacity and the instantaneous (less than 5 μ s) maximum power index will be calibrated only in the technical indicators of microwave passive components such as loaders and attenuators. Some radar design manuals and works on microwave transmission have mentioned the power capacity values of some types of contacts, but they are all conservative empirical values (with safety factor added).