Patent ID: 7945225

Claim:
An apparatus for combining an FM signal with a digital signal of the same channel to form an IBOC signal, comprising: a first input for an FM signal and a second input for a digital signal, an input quadrature hybrid connected to said first input for splitting said FM signal and applying said split FM signal to an input of a pair of RF filters tuned to pass the FM signal and to partially reflect the digital signal, an output quadrature hybrid connected to said second input for splitting said digital signal, applying said split digital signal to an output of said pair of RF filters, and recombining the partially reflected split digital signal, and a single load output connected to said output quadrature hybrid, wherein, said split FM signal passes through said pair of RF filters and is recombined at the output quadrature hybrid and said partially reflected split digital signal is recombined at the output quadrature hybrid and is further combined with the recombined FM signal at the output quadrature hybrid to form an IBOC signal, which is directed to said single load output.