Patent ID: 7623833

Claim:
A digital exciter apparatus for a radio system comprising: a first digital modulator, having an associated first sampling rate, that is configured to produce a first digital signal representing an analog frequency modulated (FM) signal; a second digital modulator, having an associated second sampling rate, that is configured to produce a second digital signal representing an information signal suitable for application to the analog FM signal in an in-band, on-channel (IBOC) arrangement; a first digital-to-analog converter that receives one of the first digital signal, the second digital signal, and a third digital signal representing a combination of the first digital signal and the second digital signal in a specified ratio and provides one of the analog FM signal, the information signal, and the combination of the analog FM signal and the information signal to a first output of the exciter apparatus; and a second digital-to-analog converter that receives one of the first digital signal, the second digital signal, and the third digital signal and provides one of the analog FM signal, the information signal, and a combination of the analog FM signal and the information signal to a second output of the exciter apparatus.