Patent ID: 7669224

Claim:
An optical node unit (ONU) of converting and combining a frequency for outdoor in a hybrid fiber coaxial (HFC) network, the optical node unit comprising: a downstream optic-to-electric converting means for converting a downstream optic signal transferred through an optical cable network from a headend system to a downstream electric signal; a down frequency converting and combining means for isolating the downstream electric signal to a broadcasting signal transmitted as a coaxial cable usable frequency band (In-Band signal) and a band signal higher than the coaxial cable usable frequency band (Super-Band (SB) signal) , isolating each of channel signals in the SB signal, converting the isolated channel signals to downstream signals in a coaxial cable usable frequency band, and combining each of the frequency-converted downstream signals with the In-Band signal to generate a coaxial cable usable frequency band downstream signal; an up/down band isolating means for outputting each of the coaxial cable usable frequency band downstream signals inputted from the down frequency converting and combining means to a corresponding coaxial cable, or dividing an upstream signal transferred through a coaxial cable from each of subscriber's sub cells to a cable TV upstream frequency band signal and In-Band upstream channel band signal (IUC band signal) which is other upstream channel in a coaxial cable usable frequency band excepting the cable TV upstream frequency band, and outputting the cable TV upstream frequency band signal and the IUC band signal to an upstream frequency converting and combining means; an upstream frequency converting and combining means for converting the upstream signals which are the cable TV upstream frequency band signal and the IUC band signal inputted from the up/down band isolating means to channels not overlapped in the coaxial cable usable frequency band, combining the converted channel signals to generate a coaxial cable usable frequency band upstream electric signal; an up electric-to-optic converting means for receiving the optical cable usable frequency band upstream electric signal, converting the optical cable usable frequency band upstream electric signal to an upstream optical signal, and outputting the upstream optical signal to the headend system through an optical cable network; and a local oscillating means for generating local oscillating signal for frequency-conversion, and providing the generated local oscillating signal to the down frequency converting and combining means or the up frequency converting and combining means.