combiner

A combiner is a device or algorithm used to merge two or more input signals, data streams, or values into a single output, preserving essential information while preventing excessive interference. It is used in electronics, communications, power systems, and computing.

In radio frequency engineering, a power combiner merges signals from multiple transmitters or routes several signals to a single antenna. They can be passive networks, such as Wilkinson power combiners or hybrid junctions, designed to provide isolation between ports and controlled insertion loss. Practical designs must address impedance matching, port isolation, power handling, and spectral compatibility. In other contexts, combiners are used to merge RF channels or to combine outputs from multiple amplifiers feeding a common load or antenna.

In solar photovoltaic systems, a combiner box collects strings of solar panels, fuses them, and presents a single output to the inverter. It typically includes protective features, wiring insulation, and monitoring for each input, enabling organized and safe aggregation of multiple panel strings.

In computing and data processing, a combiner is a function or component that merges partial results. In functional programming, a combiner refers to a binary operation that can be applied associatively to build larger results, often forming a monoid. In distributed computing frameworks such as MapReduce, a combiner runs on map tasks to partially reduce data before transfer to the reducer, reducing network traffic and workload on downstream stages.

The term is widely used across industries with context-specific implementations, but the core idea remains the same: merging multiple inputs into a single coherent output.