Coaxial Cables for Antennas: Best Practices


Antennas can use different types of coaxial cables, but there are some best practices to follow. For example, keep the coax run as short as possible to ensure the strongest transmission signal. Also, remember that the smaller the diameter, the less efficient the cable. Yet there are applications where cables with thicker copper cores come with unwanted tradeoffs.

There are many connector types for axial coaxial cables, but connector selection is largely a matter of preference. Still, using the wrong type of connector (or cable) can make a signal stronger or weaker than what’s required. This article from MP Antenna describes some best practices for antenna coaxial cables. They apply to all types of products, including the multi-polarized antennas that MP provides.

Understand Your Link Budget

A link budget is a way of accounting for all of the gains and losses in a communications system so that you can predict how reliably a signal is received. In part, the power you transmit is a function of cable type, connector type, and antenna gain. An additional factor is free space path loss, which depends on the nature of the environment. Crimping, clamping, or soldering can also affect your link budget. 

Choose the Right Coaxial Cable

The table below contains signal loss information for some common types of coaxial cable. Consider this information for your link budget, but keep tradeoffs in mind. For example, RG-58 coax cable is inexpensive but doesn’t work especially well. LMR-600 cable has a thicker copper core for less loss, but it’s difficult to work with because of its narrow bend radius. Consequently, it’s used mainly in straight-run applications.  

For applications like microwave links with tall towers, remember that there’s considerable signal loss because of the length of the cable. To send a signal up a 300-ft. transmission tower, a 100-watt amplifier is typically used. With unmanned aerial vehicles (UAVs), however, even a 7-ft. cable could be too long because of the amount of loss.    

Choose the Right Connector

The loss from a connector is very small, but a poor connection limits performance. The way that a connector is attached is also a factor. For example, a connector that’s directly attached to the antenna on a radio may work fine. However, adding a jumper in between could introduce a problem. Size is also a factor. SMA connectors take up less space, but bigger, bulkier Type N connectors are harder to shake loose. 

Ask MP About Coaxial Cables for Antennas

MP Antenna of Elyria, Ohio (USA) can help you choose the right coaxial cables for the multi-polarized antennas that you buy from us. Our antenna accessories are easy to order, ready to customize, and built to meet your specific requirements. To learn more, contact us.