It’s one of the radio industry’s most common ways to divide power and frequency signals. But beyond being a useful device, there are some functions, limitations and characteristics that set directional couplers apart. Becoming as familiar as possible with these quirks and features will help you get the most out of their unique capabilities.
Why Use a Coupler?
As in most projects, there are usually a few different ways to achieve the task of rerouting radio signals. Using the right RF directional coupler, however, will provide more than a solution to one problem. For starters, it is simple in its design and can be applied to various jobs. More than just a gadget, this tool can regulate the amount of power being coupled. It will also measure signals and ensure they follow the proper course. While directional couplers aren’t interchangeable and only direct radio frequencies in one direction, they are configurable. Begin the process in any port and the mechanism will take care of the rest.
When Should You Consider Them?
There is little doubt a directional coupler can be a useful tool when installed appropriately. Since no device is suited for every instance, though, it is important to understand what it can and can’t do. For starters, there are a total of four ports. They are known, in order, as the input, output, coupled, and isolated — or terminated — ports. Though the design is similar in all cases, be sure to determine how much power you need to run through the device. This can vary depending on the coupler, with each variation best suited for a particular job.
What Are Possible Concerns?
Power loss is common through this method and is typically due to either mainline or coupling loss. Also keep in mind power level differences between ports 1 and 4, known as isolation, and between ports 3 and 4, known as directivity.
Couplers might not be the most commonly used item in your toolbox. But with a little research, you’ll know exactly when to put them to use.