A building has six floors plus a basement. Each floor is 929 sq m (10,000 sq ft) and has approximately 50 CATV outlets respectively. There is a single hardline trunk cable installed from the…

A splitter divides the input signal equally among all output ports, imposing a 3.5 dB or greater loss on every port including the through path, causing cumulative loss that is unacceptable across six floors.

A directional coupler has two output paths: a 'through' port with very low insertion loss (typically 1-2 dB) that passes the bulk of the signal on to the next floor, and a 'tap' port that couples off a defined, smaller portion of signal for local distribution. This design preserves signal strength along the trunk across multiple floors, which is exactly what a multi-story riser system requires.

A multiport tap is designed to branch signal to multiple outlets on a single floor and imposes higher through-loss than a directional coupler, making it unsuitable for maintaining trunk signal strength between TRs.

A combiner is used to merge multiple input signals onto one output; it does not pass a trunk signal forward and cannot serve a distribution function in this context.