The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 1987
Filed:
Mar. 02, 1984
U.S. Philips Corporation, New York, NY (US);
Abstract
A wide-band frequency modulated DBS signal of the type having time sequential compressed chrominance and luminance (video) components is received by an aerial (1), frequency converted in a down converter (2) and applied to the input (4) of a conversion unit. The conversion unit has a tuner (5), i.f. stage (9,10) and a frequency demodulator (11) to produce baseband video which is applied after de-emphasis at (12) to a modulator (27) where the video is amplitude modulate onto a vision carrier from an oscillator (28). The modulated carrier is applied through a vestigial sideband filter (29) and an adder (30) to an output (31). Sound/data bursts present in the DBS signal are recovered in a stage (13) and processed in a processor (14) where the sound/data bursts are expanded to occupy approximately a line period at a bit rate which is an integral sub-multiple of the bit rate for the sound/data bursts in the received DBS signal. The expanded sound/data and clock frequency are digitally modulated in a modulator (32 ) onto a sound carrier from an oscillator (33), the modulated sound carrier being applied through a bandpass filter (34) and the adder (30) to the output (31). The output (31) is connected to a cable distribution system for which the narrow band signals produced by the conversion unit are suited as such systems cannot cope with high bit-rates. The processing of the sound/data bursts such that their bit rate is substantially reduced also simplifies the handling and demodulation processes for these bursts.