Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
329 words
An interface for use with television receiver, which television receiver includes a tuner for selecting one of a plurality of programs each carried on a separate carrier frequency within the television broadcast band and converting the selected program to an intermediate frequency carrier and an intermediate frequency amplifier for amplifying signals within a predetermined frequency band about said intermediate frequency carrier, and converter/decoder means for converting programs carried on a selected carrier frequency to a first predetermined carrier frequency in the television broadcast band and for decoding program information carried thereon, which converter/decoder means has an input port for receiving signals to be converted and decoded and an output port at which the converted and decoded program appears, said interface comprising: splitter means for receiving a plurality of encoded program signals, each carried on a different carrier frequency within the television broadcast band, and for dividing said encoded program signals into first and second substantially identical components; a first signal path for transmitting said first program signal component to the input port of said tuner; a signal adder having two input ports and an output port, the signal at the output port being the sum of the signals at the input ports; a second signal path for transmitting said second program signal component to a first input port of said signal adder; an upconverter for converting the program selected by said tuner from the intermediate frequency carrier frequency output of said tuner to second predetermined frequency in the television broadcast band; a third signal path for transmitting the output of said upconverter to a second input port of said signal adder; a fourth signal path for transmitting the output of said signal adder for input to said converter/decoder means, a downconverter for converting program signals produced by said converter/decoder means at the output port thereof to said intermediate frequency carrier, and a fifth signal path for transmitting the output of said downconverter for input to said intermediate frequency amplifier.
Claim 2
Dependent Claim
329 words
An interface for use with television receiver, which television receiver includes a tuner for selecting one of a plurality of programs each carried on a separate carrier frequency within the television broadcast band and converting the selected program to an intermediate frequency carrier and an intermediate frequency amplifier for amplifying signals within a predetermined frequency band about said intermediate frequency carrier, and converter/decoder means for converting programs carried on a selected carrier frequency to a first predetermined carrier frequency in the television broadcast band and for decoding program information carried thereon, which converter/decoder means has an input port for receiving signals to be converted and decoded and an output port at which the converted and decoded program appears, said interface comprising: splitter means for receiving a plurality of encoded program signals, each carried on a different carrier frequency within the television broadcast band, and for dividing said encoded program signals into first and second substantially identical components; a first signal path for transmitting said first program signal component to the input port of said tuner; a signal adder having two input ports and an output port, the signal at the output port being the sum of the signals at the input ports; a second signal path for transmitting said second program signal component to a first input port of said signal adder; an upconverter for converting the program selected by said tuner from the intermediate frequency carrier frequency output of said tuner to second predetermined frequency in the television broadcast band; a third signal path for transmitting the output of said upconverter to a second input port of said signal adder; a fourth signal path for transmitting the output of said signal adder for input to said converter/decoder means, a downconverter for converting program signals produced by said converter/decoder means at the output port thereof to said intermediate frequency carrier, and a fifth signal path for transmitting the output of said downconverter for input to said intermediate frequency amplifier.
Claim 3
Dependent Claim
19 words
The interface of claim 1 wherein said first predetermined carrier frequency is equal to said second predetermine carrier frequency.
Claim 4
Dependent Claim
20 words
The interface of claim 2 wherein said upconverter and said downconverter share a common constant frequency source for frequency conversion.
Claim 5
Dependent Claim
25 words
The interface of claim 1 wherein said second signal path includes filter means for rejecting signals in a band about said second predetermined carrier frequency.
Claim 6
Dependent Claim
28 words
The interface of claim 4 wherein the rejection bandwidth of said filter means is between 1 and 3 times as wide as the bandwidth of a television channel.
Claim 7
Independent Claim
134 words
A method for selecting and decoding subscription television programs carried on a plurality of carrier frequencies in the television broadcast band comprising: splitting said programs into first and second substantially identical components; selecting the desired program from said first component; converting said desired program from its television broadcast band carrier frequency to an intermediate frequency carrier; converting the desired program from said intermediate frequency carrier to a first predetermined carrier frequency; adding said second component to the desired program on said first predetermined carrier frequency to produce a composite signal; decoding and converting the portion of said composite signal carried on said first predetermined carrier frequency to a second predetermined carrier frequency; converting the decoded program from said predetermined frequency carrier to said intermediate frequency for amplification and further processing by a television receiver.
Claim 8
Independent Claim
134 words
A method for selecting and decoding subscription television programs carried on a plurality of carrier frequencies in the television broadcast band comprising: splitting said programs into first and second substantially identical components; selecting the desired program from said first component; converting said desired program from its television broadcast band carrier frequency to an intermediate frequency carrier; converting the desired program from said intermediate frequency carrier to a first predetermined carrier frequency; adding said second component to the desired program on said first predetermined carrier frequency to produce a composite signal; decoding and converting the portion of said composite signal carried on said first predetermined carrier frequency to a second predetermined carrier frequency; converting the decoded program from said predetermined frequency carrier to said intermediate frequency for amplification and further processing by a television receiver.
Claim 9
Dependent Claim
15 words
The method of claim 6 wherein said first and second predetermined carrier frequencies are identical.
Claim 10
Dependent Claim
39 words
The method of claim 6 wherein said second component is processed to exclude signals lying in a band about said first predetermined carrier frequency prior to adding the same to the desired program on said first predetermined carrier frequency.