Noise-having reverse signal isolator and reverse signal combining device in service system using CATV network
AssigneeSamsung Electronics Co., Ltd.
InventorJeong-Sik Na
Life of this patent
Estimating the term…
Abstract
A noise-having reverse signal isolator and a reverse signal combining device in a service system using a CATV network, for preventing noise introduced in a reverse signal from affecting other reverse signals. The reverse signal combining device includes a plurality of noise isolators and a combiner. The noise isolators determine whether noise is introduced into a plurality of reverse signals, isolate a corresponding reverse signal in the presence of noise, and output the reverse signals in the absence of noise. The combiner combines the outputs of the plurality of the noise isolators.
Claims18
A noise-having reverse signal isolator in a cable television service system, comprising:
- a divider for dividing a reverse signal into a first signal and a second signal;
- a bandpass filter for passing only a signal in a noise-susceptible band from the first signal received from the divider;
- a detector for converting an output of the bandpass filter to a direct current (DC) signal;
- a DC amplifier for generating an amplified DC signal by DC-amplifying the DC signal output from the detector;
- a matching resistor having one end grounded and having a predetermined resistance value;
- a switch having a first input terminal connected to an output of said divider for receiving said second signal, a second input terminal connected to another end of said matching resistor and an output terminal, said switch selectively connecting one of the first and second input terminals to said output terminal;
- and
- a controller for determining whether noise exists in the reverse signal by comparing the amplified DC signal output from said DC amplifier with a reference DC signal and controlling said switch based on the determination.
A noise-having reverse signal isolator in a CATV-using service system, comprising:
- an amplifier for generating an amplified reverse signal by amplifying a reverse signal;
- a divider for dividing said amplified reverse signal into a first signal and a second signal;
- a bandpass filter for passing only a signal in a noise-susceptible band from the first signal received from the divider;
- a detector for converting the output of the bandpass filter to a direct current (DC) signal;
- a DC amplifier for generating an amplified DC signal DC-amplifying the DC signal output from the detector;
- a resistor having one end connected to a ground terminal;
- a high-frequency switch having a first input terminal connected to receive said second signal from an output of the divider, a second input terminal connected to another end of said resistor and an output terminal, said high-frequency switch selectively connecting one of the first and second input terminals to said output terminal;
- a controller for determining whether noise exists in the reverse signal by comparing the amplified DC signal output from the DC amplifier with a reference DC signal and controlling said high-frequency switch based on a result of the determination;
- and
- an attenuator for controlling the output level of a signal output from said output terminal of said high-frequency switch.
A reverse signal combining device in a CATV-using service system, comprising:
- a plurality of noise isolators for determining whether noise is introduced into a plurality of reverse signals, isolating a corresponding reverse signal in the presence of noise, and outputting the reverse signals in the absence of noise, each said noise isolator comprising:
- a divider for dividing said reverse signal into a first signal and a second signal;
- a resistor having one end connected to a ground terminal;
- and
- a high-frequency switch having a first input terminal connected to receive said second signal from an output of the divider, a second input terminal connected to another end of said resistor and an output terminal, said high-frequency switch selectively connecting said first input terminal to said output terminal when no noise exists in said first signal and connecting said second input terminal to said output terminal when noise exists in the first signal;
- and
- a combiner for combining the outputs of the plurality of the noise isolators.
Dependencies are inferred from the claim text.