House amplifier with return path gating

Abstract

In a traditional HFC plant, the return path signals originating from cable modems, eMTAs, and settop boxes are transmitted in the 5-42 MHz range (other countries use frequencies such as 5-30 MHz, 5-55 MHz, and 5-65 MHz). These signals with entry points at any RF connection point in the home are combined by RF combiners at the side of the house. Furthermore, RF return path signals from multiple homes are combined by RF taps into a coaxial cable TV plant, and transmitted back to a hub or headend either in RF or thru a fiber optic network. In addition to combining all RF signals, the return path system combines all the ingress noise from all the RF connection points, which has an adverse impact on signal quality. This invention takes advantage of the burst nature of RF return path signals to insert an automatic gating function into the return signal path of a house amplifier so that the return signal path is shut off or attenuated when no RF return signal is present. This has the advantage of eliminating completely any ingress noise contribution when the cable modem, eMTA, or settop box are not actively transmitting, thereby improving overall coaxial cable plant's signal quality.

1 . A house amplifier with an integrated RF gate in the return signal path that is controlled automatically by an automatic detection circuit. 
   
   
       2 . The house amplifier of  claim 1  where the gating function eliminates return path ingress noise when the cable modem, eMTA and settop box are not actively transmitting data. 
   
   
       3 . The house amplifier of  claim 1  where the automatic detection circuit consists of an RF detector, amplifier, and timing circuit. 
   
   
       4 . The house amplifier of  claim 1  where the automatic detection circuit eliminates the need for intervention from a human operator. 
   
   
       5 . The house amplifier of  claim 1  where the automatic detection circuit does not interrupt data communications. 
   
   
       6 . The house amplifier of  claim 1  where the timing circuit of the automatic detection circuit provides for a delay circuit to prevent ‘early shutoff’ and thus avoid data loss. 
   
   
       7 . The house amplifier of  claim 1  where the RF gate can be an RF switch or a voltage controlled variable attenuator. 
   
   
       8 . The house amplifier of  claim 1  where the number of RF output ports can vary from 1 to N number of ports. 
   
   
       9 . The house amplifier of  claim 1  where the forward path can be amplified or passive pass through. 
   
   
       10 . The house amplifier of  claim 1  where the return path can be amplified or passive pass through.