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US 7,643,099 B2Granted
Television system with controlled tuning
AssigneeKoninklijke Philips Electronics N.V.
InventorsJanardhana Bhat, Akbar Hassan Syed, Teck Tem Leong
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AssigneeKoninklijke Philips Electronics N.V.
InventorsJanardhana Bhat, Akbar Hassan Syed, Teck Tem Leong
Estimating the term…
Television systems comprising tuners (1), controllers (2) for controlling tuners (1), and stages (3) for receiving tuned signals from tuners (1) and for supplying control signals to controllers (2), use time-consuming automatic fine tuning signals while high speed tuning. By using lock signals (53) from phase-locked-loops (31) in stages (3) as control signals, an indication whether a channel is active or not can now be got much quicker due to lock signals being much faster available than automatic fine tuning signals. By using synchronization signals (54) from synchronization generators (4) as further control signals, a further indication is got. In a fast tuning mode, frequencies nearby active channels are detected, and in a fine tuning mode, channel frequencies are identified. According to the basic idea, lock signals originating from phase-locked-loops (31) in stages (3) can give first indications whether a channel is active or not, preferably and further advantageously in combination with second indications based upon synchronization signals (54).
A television system comprising a tuner for tuning video signals, a controller for controlling said tuner, and a stage for receiving tuned signals from said tuner and for supplying at least one control signal to said controller, wherein said stage comprises an automatic fine tuning unit for generating an automatic fine tuning signal and a phase-locked-loop for generating a lock signal more quickly available than the automatic fine tuning signal, said lock signal forming said at least one control signal for said controller to provide an indication whether a channel at a tuned frequency is active or not,
A controller for use in television system comprising a tuner for tuning video signals and said controller for controlling said tuner and a stage for receiving tuned signals from said tuner and for supplying at least one control signal to said controller, wherein said stage comprises an automatic fine tuning unit for generating an automatic fine tuning signal and a phase-locked-loop for generating a lock signal more quickly available than the automatic fine tuning signal, said lock signal forming said at least one control signal for said controller to provide an indication whether a channel at a tuned frequency is active or not, wherein said television system comprises a synchronization generator for synchronizing video signals originating from said stage and for supplying at least one synchronization signal to said controller, said controller comprising a switch for, in dependence of said lock signal, taking or not taking into account said synchronization signal.
A method for use in television system comprising a tuner for tuning video signals and a stage for receiving tuned signals from said tuner, said method comprising the steps of:
Dependencies are inferred from the claim text.