Subscription TV audio carrier recovery system
First Claim
1. A TV decoder for processing TV audio and video signals in which the audio information is received on an audio subcarrier including filter means for separating audio carrier information and video carrier information signals, demodulating means for separating the audio carrier information signal from the audio information subcarrier, means for multiplying the audio information subcarrier to raise it to the frequency of the audio carrier information signal and means for recombining the video carrier information signal with the increased frequency audio information subcarrier.
12 Assignments
0 Petitions
Accused Products
Abstract
A subscription TV decoder for processing encoded audio and video signals in which the TV program audio information is received as an audio subcarrier includes means for decoding the video signal, a filter for separating the decoded video and audio signals, and a filter for separating the audio signal from the audio information subcarrier. The audio information subcarrier is multiplied to raise it to the frequency of the audio signal and is then recombined with the decoded video signal.
-
Citations
11 Claims
- 1. A TV decoder for processing TV audio and video signals in which the audio information is received on an audio subcarrier including filter means for separating audio carrier information and video carrier information signals, demodulating means for separating the audio carrier information signal from the audio information subcarrier, means for multiplying the audio information subcarrier to raise it to the frequency of the audio carrier information signal and means for recombining the video carrier information signal with the increased frequency audio information subcarrier.
- 3. A TV decoder for processing encoded audio and video signals in which the TV program audio information is received as an audio subcarrier, including means for decoding the video signal, filter means for separating video and audio carrier information signals, demodulating means for separating the audio carrier information signal from the audio information subcarrier, means for multiplying the audio information subcarrier to raise it to the frequency of the audio carrier information signal, and means for recombining the video carrier information signal with the increased frequency audio information subcarrier.
- 9. A TV decoder for processing amplitude modulated encoded audio and video carrier information signals in which the TV program audio information signal and a decoder enabling signal are each received as audio subcarriers, including decoder enabling means responsive to said decoder enabling subcarrier, means for detecting the amplitude modulation on the audio carrier information signal, means for applying said detected audio carrier information signal amplitude modulation to said encoded video carrier information signal to decode it, filter means for separating the video and audio carrier information signals, demodulating means for separating the audio carrier information signal from the audio information subcarrier, means for multiplying the audio information subcarrier to raise it to the frequency of the audio carrier information signal, and means for recombining the video carrier information signal with the increased frequency audio information subcarrier.
Specification