Abstract: A video signal processing apparatus and method, and more particularly, digital broadcast signal processing apparatus and method in which channel interference by an analog broadcast is prevented, for effectively removing an analog broadcast signal mixed in a digital broadcast signal of a co-channel, are provided. According to the above apparatus and method, a frequency offset is corrected by operating the frequency offset of a carrier signal and automatically performing fine tuning and the characteristic of an NTSC rejection filter (NRF) is improved by processing the signal whose frequency offset is corrected by the NRF. Accordingly, it is possible to effectively prevent a co-channel interference phenomenon by the analog broadcast from occurring when the digital broadcast signal is processed, to thus reduce noise.

Abstract: In a receiving device of the invention used in high-definition television, a frequency information storage section stores error information of a frequency error of a signal output from an oscillator. A control unit controls the oscillator based on the error information stored in the frequency information storage section. In a simple configuration, it is, therefore, possible to shift, the frequency in a direction of tuning by a tuner, to thereby output the signal with an appropriate frequency from the oscillator without being influenced by an accuracy of the oscillator, thus to demodulate the received signal accurately. Accordingly, it can be avoided such a problem that no pilot signal is present in an IF signal within a predetermined band width filtered by a SAW filter or that the pilot signal, even if present, cannot be received.

Abstract: A digital television receiver converts very-high-frequency intermediate-frequency digital television signal to a band with uppermost frequency in the lower portion of the high-frequency range. This facilitates RLC analog filtering, such as a Butterworth-Thomson-transition filter or a bridged-T trap filter, being used for suppressing the frequency-modulated audio carrier of co-channel NTSC analog television signal prior to the digital television signal being synchrodyned to baseband for recovering symbol code. The delay distortion introduced by this analog filtering is compensated for in substantial part in surface-acoustic-wave bandpass filtering of the very-high-frequency intermediate-frequency digital television signals. Remnant delay distortion is reduced by channel equalization filtering carried out in the digital regime.

Abstract: An automatic frequency tracking apparatus and method for a receiver for receiving a television signal including a pilot signal which can automatically track and compensate for the frequency offset of the received television signal even in a case where the frequency offset deviates from a determined range in which carrier restoration is possible. According to the method, a maximum frequency offset range which can occur in receiving a television signal is divided into a plurality of window regions, and each window region is searched to determine if a lock signal of a frequency phase-locked loop is detected at representative frequencies of the respective divided window regions in a wide-range tracking adjustment mode performing step.

Abstract: A fine tuning apparatus in a digital television receiver, including a tuner including first and second local oscillators, a channel decoder for outputting an error value with respect to the degree of frequency deviation of an RF signal from its regular frequency band, the RF signal being tuned by a tuner, and a microprocessor for receiving an error value output from the channel decoder and controlling the second local oscillator in the tuner to reduce the error value. Thus, fine control can be made regardless of a predetermined fine control range in a field which uses a digital television.

Abstract: An automatic frequency control circuit includes a phase difference detection circuit, average value calculation circuit, weighting circuit, and phase correction circuit. The phase difference detection circuit obtains the phase difference between pattern signals per period on the basis of a quadrature-demodulated pattern signal component and a pattern signal component one period before the quadrature-demodulated pattern signal component. The average value calculation circuit calculates the average value of first phase differences between the pattern signals repetitively output from the phase difference detection circuit, thereby obtaining a second phase difference in units of symbols in the current burst. The weighting circuit weights the second phase difference from the average value detection circuit and a third phase difference up to the previous burst, thereby obtaining a fourth phase difference up to the current burst.

Abstract: The present invention pertains to a method and device for precision tuning and a method and device for matching a vestigial sideband signal in a television, which prevent a direct current boost-up when a vestigial sideband signal is shifted to a base band in a carrier recovery device of a short loop using a digital frequency and phase locked loop. A precision tuning method in a television includes the steps of receiving a plurality of vestigial sideband signals in a radio frequency band, shifting only a vestigial sideband signal of an intended channel to be tuned among the plurality of vestigial sideband signals to a base band, outputting the baseband-shifted vestigial sideband signal, generating a direct current estimated value by taking an average of the baseband-shifted vestigial sideband signal, and controlling a tuning frequency of a tuner based on the direct current estimated value.

Abstract: Phase locked loop (PLL) detection circuit that can improve the stability of operation, avoid occurrence of an erroneous operation, and perform PLL lock judgment correctly. Whether a PLL circuit that consists of a phase comparator, a low-pass filter, and a VCO is in a lock state is judged based on a phase error signal in the PLL circuit. The level of the phase error signal is compared with two threshold values, VRL and VRH. When the phase error signal is somewhere between VRL and VRH, a judgment is made that the PLL circuit is in a lock state. A judgment that the PLL circuit is out of a lock state is made in the other cases. This makes it possible to output a correct and stable PLL lock judgment signal.

Abstract: A television receiver includes a tuner for receiving either analog or digital signals. Separate analog and digital demodulators are selectively coupled to the tuner through an RF switch that is controlled by a sync detector in the output of the analog demodulator. The selected one of the demodulators develops an AGC signal that is coupled to the tuner through the RF switch. In one embodiment, a two pole RF switch is used with one pole switching the IF signal and the other pole switching the AGC signal In another embodiment, a single pole RF switch is used with the tuner signal and the AGC signal being multiplexed through the switch. This is accomplished by the provision of a high frequency path and a low frequency path between each of the RF switch and the tuner, the RF switch and the analog demodulator, and the RF switch and the digital demodulator.

Abstract: Circuit and method for determining a received signal for a receiver such as a simulcast receiver or an HDTV receiver are provided. The circuit includes a first detector for detecting a first reference signal included in a received signal and outputting a first detection signal, and a second detector for detecting a second reference signal included in the received signal and outputting a second detection signal. The circuit also includes a generator for generating a determination signal which indicates that the received signal is an analog broadcasting signal in the event the first detection signal is detected, and indicates that the received signal is a high definition signal in the event if the second detection signal is detected. Therefore, the received signal can be determined correctly, according to channel selection.

Abstract: A television receiver includes an input terminal (12). Through the input terminal is inputted an input signal having a predetermined electric field intensity. That is, a tuner (14) converts the input signal into a video intermediate frequency signal and audio intermediate frequency signal. The video intermediate frequency signal is amplified by a video intermediate frequency amplifier circuit (16). Based on that frequency, a filter (26) outputs a detection signal (Va). An RF-AGC circuit (32) outputs a reference voltage (Vref). An RF-AGC circuit (30) creates a control voltage (Vb) in response to a difference between the detection signal and the reference voltage. The tuner is controlled in gain by this control voltage. The reference voltage is varied by a micro-computer (36) depending upon the control voltage. Accordingly, the control voltage is adjusted to a desired voltage value.

Abstract: A remote control multimedia content listing system for providing an updated content listing of various media within a remote control. The remote control multimedia content listing system includes a remote control having a housing, a display, a keypad, and an electronic system for receiving configuration data from a control station via a global computer network (e.g. Internet). The user may enter media information into the electronic system thereafter uploading the media information to the control station. The control station analyzes the uploaded media information and transmits the appropriate configuration data to properly configure the electronic system to provide a usable “guide” for the media. The user may also access a web site of the control station and manually enter the media information after which the control station sends the appropriate configuration data to the electronic system.

Abstract: A receiver invention includes an antenna circuit unit having a high-frequency amplifier circuit connected to a reception antenna, a receiving circuit having a channel selection key, and a coaxial cable for connecting the antenna circuit unit and the receiving circuit. The receiving circuit includes a voltage adding circuit for adding, upon channel selection based on an operation of the channel selection key, a DC voltage corresponding to a frequency band to an AGC signal to supply it to the high-frequency amplifier circuit through the coaxial cable. A high-frequency gain of the high-frequency amplifier circuit is changed by using a voltage corresponding a frequency band of a received broadcasting frequency and an electric field intensity thereof.

Abstract: In a television receiver having a tuner 2 for converting a received signal from an antenna 1 to an intermediate frequency signal and supplying the intermediate frequency signal to a homodyne detector circuit through a filter device to extract a video signal, a variable frequency oscillator is provided for changing the frequency of the intermediate frequency signal such that the frequency of beat components between a local oscillating signal of the tuner and a harmonic signal of the intermediate frequency signal is coincident with a trap frequency of the filter device. The occurrence of interference due to the intermediate frequency signal introducing into the antenna can be prevented by a simple configuration.

Abstract: Upon installation of a broadcast receiver, for example, a television receiver, the different tuning frequencies/channel numbers are to be stored in a memory of the broadcast receiver. To facilitate the installation, the network provider transmits a list of nominal tuning frequencies, for example, as a teletext page, together with at least one of the broadcast television programs. To further improve installation, also the RF frequency of a so-called subscription channel is also inserted in the list. As the RF frequency of the set-top box may differ from the nominal value in the list, a fine-tuning is performed to modify the stored tuning frequency/frequencies.

Abstract: A video display apparatus displays pictures from broadcast sources of standard or high definition pictures and may also display computer generated images. To display these sources a horizontal deflection signal generator is operable at a plurality of frequencies. The deflection signal generator comprises a controlled oscillator generating a output signal. A divider divides the output signal to form a horizontal frequency signal. A phase detector receives the horizontal frequency signal and a synchronizing signal and generates an analog signal for coupling to the oscillator. A digital to analog converter generates a voltage from a digital data word and couples the voltage to the oscillator. The voltage determines a center frequency of the oscillator and the analog signal controls the oscillator to synchronize with the synchronizing signal.

Abstract: A horizontal electron-beam deflector capable of preventing circuits from being damaged due to disturbance such as electric discharge with a simple and small circuit configuration, wherein an AFC circuit inputs a control signal indicating a frequency from a computer, the control signal is output to a deflection circuit, the AFC circuit generates a horizontal synchronization pulse signal, and the deflection circuit generates a horizontal deflection signal while controlling a voltage by using the control signal input from the AFC circuit.

Abstract: A frequency diversity system for use in mobile reception of television and RF signals in the meter or decimeter wavelength, such as for use with a mobile television having a first receiver, an additional receiver and a control and analysis circuit. The additional receiver detects all incoming frequencies corresponding to a preset program and switches the main receiver to an incoming frequency of a higher quality. The receiver is able to identify the frequencies corresponding to the desired program through a transmitter identification code, which is added to each signal. This code is usually a VPS identification signal. The control and analysis circuit compares the incoming frequencies to the frequency of the signal transmitted by the television receiver to determine the highest quality signal. In order to accelerate the process, the system processes local position coordinates of the television so that the frequencies analyzed are only those expected within the coverage area of the television.

Abstract: A method and apparatus for wide range automatic frequency control. A control signal indicating a frequency within one of a plurality of frequency bands is received by an oscillator. In response, the oscillator generates a tuning signal having the indicated frequency. Based on the tuning signal, receive logic receives an input signal to obtain a sequence of values. Compare logic compares the sequence of values to a predetermined pattern. If the sequence of values does not match the predetermined pattern, frequency control logic outputs a different control signal to the oscillator to adjust the frequency of the tuning signal to another one of the plurality of frequency bands. Another input signal is received to obtain a new set of values and the new set of values is compared the predetermined pattern.

Abstract: A first mixer outputs a TV signal of a first intermediate frequency (the first IF) by up-converting an input signal. A second mixer outputs a TV signal of the second intermediate frequency (the second IF) by down-converting the TV signal of the first IF. The second IF is chosen to be different and below the conventional intermediate frequency used by single super-heterodyne analog TV tuners. By choosing a sufficiently low second IF, the passband signal can be directly sampled by an analog to digital converter after being filtered by a low pass filter. Thus, a digital television broadcast receiver tuner is achieved which can be used with a direct passband sampling type digital demodulator.

Abstract: An automatic tuning apparatus capable of automatically switching the tuning mode of a tuner circuit, automatically arranging various signal data in or after completion of tuning and arbitrarily and automatically arranging various signal data by the user comprises a SYNC discrimination circuit (11) discriminating whether a video signal system is the NTSC system or another system, a tuning mode switching circuit (12) for switching the tuning mode, and a color discrimination circuit (13) receiving a color bust signal (identical signal) for discriminating whether the video signal system is the PAL system or the SECAM system. As to the NTSC system, the PAL system, the SECAM system and the SECAM-L system, the user may not set the tuning mode of tuning means, whereby an automatic tuning apparatus imposing no burden on the user can be obtained.

Abstract: Radio receivers for receiving ATSC DTV signals or NTSC analog TV signals each use a single first detector for both types of signal that supplies its output signals to an intermediate-frequency amplifier chain for DTV signals and to another intermediate-frequency amplifier chain for analog TV signals. In some receivers the sound carrier of the NTSC signal has a separate, further IF amplifier chain. When DTV signals are determined to be received, or alternatively when analog TV signals are determined not to be received, the first detector is conditioned for automatic fine tuning in response to the pilot carrier of received DTV signal. When DTV signals are determined not to be received, or alternatively when analog TV signals are determined to be received, the first detector is conditioned for automatic fine tuning in response to the video carrier of received analog TV signal. The determination of whether or not DTV signal is received is made in response to the amplitude of DTV signal pilot carrier.

Abstract: An automatic tuning apparatus capable of automatically switching the tuning mode of a tuner circuit, automatically arranging various signal data in or after completion of tuning and arbitrarily and automatically arranging various signal data by the user comprises a SYNC discrimination circuit (11) discriminating whether a video signal system is the NTSC system or another system, a tuning mode switching circuit (12) for switching the tuning mode, and a color discrimination circuit (13) receiving a color bust signal (identic signal) for discriminating whether the video signal system is the PAL system or the SECAM system. As to the NTSC system, the PAL system, the SECAM system and the SECAM-L system, the user may not set the tuning mode of tuning circuit, whereby an automatic tuning apparatus imposing no burden on the user can be obtained.

Abstract: An input high frequency signal passes through a PIN diode having a variable high frequency resistance and is output from an AGC circuit. The PIN diode is connected so as to be biased forward between an AGC signal level and a fixed voltage level (such as ground potential). A bias resistor and a coil are connected in series between a node on the output side of the PIN diode and a node supplied with the ground potential. More specifically, the resistor and the coil are inserted in parallel between the transmission path for high frequency signals and the ground potential.

Abstract: A frequency and phase regulating circuit, particularly for a digital complex-value vestigial sideband signal or Nyquist flank-filtered signal, with a regulating loop having a filter device which generates, from the signal to be regulated, a symmetrical double sideband signal band-delimited to a reference frequency. This regulating circuit is particularly suitable for a digital TV demodulator.

Abstract: A double conversion television tuner capable of receiving analog and digital telecasts and having a reduced number of frequency conversion stages with fewer oscillators to minimize beat disturbances between local oscillation signals, the tuner being made up of fewer circuit components costing less than conventional tuners to manufacture. The inventive tuner comprises a first frequency conversion stage for converting in frequency a channel-select received signal to a first intermediate frequency signal to be output, a second frequency conversion stage for converting in frequency the first intermediate frequency signal to a second intermediate frequency signal to be output, and an analog and a digital demodulator for demodulating the second intermediate frequency signal.

Abstract: For a possible simple structure, dispensing with ceramic filters, an FM demodulator for demodulating sound-FM signals comprises a controllable amplifier (1) which receives the sound signals converted to intermediate frequencies, said amplifier having a gain which is adjusted by means of an amplitude control circuit (4) and whose output signal is applied to the amplitude control circuit and to the phase-locked loop which supplies a demodulated sound signal in the locked-in state from its output, said phase-locked loop including a loop filter (7) which comprises a filter (8, 9, 10) of at least the second order with a pole at the frequency f=0, and a limit-detection circuit (13) which feeds back the operating frequency of the phase-locked loop to a predetermined frequency range when said phase-locked loop leaves this frequency range around a predeterminable nominal demodulation frequency, the amplitude control circuit (4) controlling the controllable amplifier (1) in dependence upon its output signal and a signa

Abstract: An automatic tuning apparatus is capable of automatically switching a tuning mode of a tuner circuit, automatically arranging various signal data in or after completion of tuning and arbitrarily and automatically arranging various signal data by a user. The apparatus comprises a SYNC discrimination circuit (11) for discriminating whether or not a video signal system is a NTSC system or another system, a tuning mode switching circuit (12) for switching a tuning mode, and a color discrimination circuit (13) for receiving a color burst signal (identic signal) for discriminating whether the video signal system is a PAL system or a SECAM system. As to the NTSC system, the PAL system, the SECAM system and a SECAM-L system, the user may not set the tuning mode of tuning means, whereby an automatic tuning apparatus imposing no burden on the user can be provided.

Abstract: A demodulator and a demodulation method are designed so as to reduce the load of a CPU. A host CPU controls a digital demodulation circuit, an error correction circuit, a transport circuit and an MPEG decoder through a bus. The host CPU outputs a control signal to a format conversion circuit via a CPU interface when it instructs a tuner to perform tuning. The format conversion circuit converts the format of this control signal into a 3-wire format and outputs the converted signal to a frequency divider of the tuner.

Abstract: A data transmission apparatus applicable to transmission of data by the use of a cable of a television camera system or the like and capable of ensuring simplified exact demodulation of data transmitted through quadrature modulation. The apparatus comprises a demodulator for outputting detection signals of the quadrature-modulated signal based on reference signals whose phases are each different by a predetermined value from an I-axis reference signal and a Q-axis reference signal in the quadrature modulation; a signal level corrector for correcting the signal levels of the detection signals; and a signal converter for converting the output signals of the signal level corrector to detection signals based on the I-axis and Q-axis reference signals. An equalizer circuit is further included in the apparatus for adaptively equalizing the output signals of the signal converter or the output signals of the signal level corrector.

Abstract: An automatic tuning apparatus capable of automatically switching the tuning mode of a tuner circuit, automatically arranging various signal data in or after completion of tuning and arbitrarily and automatically arranging various signal data by the user comprises a SYNC discrimination circuit (11) discriminating whether a video signal system is the NTSC system or another system, a tuning mode switching circuit (12) for switching the tuning mode, and a color discrimination circuit (13) receiving a color bust signal (identic signal) for discriminating whether the video signal system is the PAL system or the SECAM system. As to the NTSC system, the PAL system, the SECAM system and the SECAM-L system, the user may not set the tuning mode of tuning circuit, whereby an automatic tuning apparatus imposing no burden on the user can be obtained.

Abstract: To make it possible to receive a modulated signal which is obtained by suppressing a carrier signal such as a high definition TV signal which is digitally demodulated such as QAM (quadrature amplitude modulation), a receiver of the double super-heterodyne system having the first and second mixers 9 and 13 is a basic constitution. A band pass filter having a flatness in pass band and a small deviation of group delay which will prevent the demodulation of a high definition TV signal from degradation is used a first intermediate frequency filter 11. An SAW filter is used as a second intermediate frequency filter 16. The third mixer 28 for converting a second intermediate frequency signal to a third intermediate frequency signal in frequency is installed and the frequency of the third intermediate frequency signal to be converted is set to a value lower than the frequency of the second intermediate frequency signal.

Abstract: A video receiving device (A) that includes a circuit for receiving first video signals from a remote transmitter, a circuit for receiving second video signals from another video receiver (TVS), a circuit (TU1) for automatic searching for transmission channels, and a circuit (PC) for phase comparison between the vertical synchronization signals of the first video signals and the vertical synchronization signals of the second video signals that can output an "outphasing" signal that is used for controlling the operation of the automatic channel search circuit, wherein the video receiving device (A) also includes a control circuit (CC) that enables the video signals that it is receiving to be displayed for a pre-determined time on the other video receiver (TVS). The invention is applicable notably to the programming of video recorders, and to the automatic tuning of such a recorder to the channel being viewed on a TV receiver in order to enable simple and immediate recording of this channel.

Abstract: Two tuner sections are provided in a video receiving apparatus so that a first tuner receives and outputs a television broadcasting signal desired by a user, a second tuner section executes an automatic fine tuning operation at previously set time intervals to discriminate a deviation of the oscillating frequency of the local oscillating section, and when the deviation of the discriminated oscillating frequency is less than a previously set predetermined value, the local oscillating section of the first tuner section is controlled to continuously oscillate at a present oscillating frequency of the second tuner.

Abstract: A television signal receiver for processing an HDTV signal transmitted in a vestigial sideband (VSB) format includes input complex filters shared by a timing recovery network (30) and a carrier recovery network (50). The filter network includes a pair of upper and lower band edge filters (20, 22) mirror imaged around the upper and lower band edges of the VSB signal for producing suppressed subcarrier AM output signals. The timing recovery network includes a phase detector (28, 38, 62) and responds to an AM signal derived from the two filters (via 26) for synchronizing a system clock (CLK). The carrier recovery network (50) also includes a phase detector (54, 60, 62, 64), and responds to outputs from one or both of the filters for producing an output error signal (.DELTA.) representing a phase/frequency offset of the VSB signal. The error signal is used to reduce or eliminate the offset to produce a recovered baseband or near baseband signal.

Abstract: A digital data receiver comprising a first frequency converter for converting a high frequency digital orthogonal modulation signal into a first intermediate frequency signal based on a first local oscillation signal, a second frequency converter for converting the first intermediate frequency signal into a second intermediate frequency signal based on a second local oscillation signal, and a demodulator for performing a orthogonal demodulation to the second intermediate frequency signal based on a third local oscillation signal, wherein the first local oscillation signal is generated by a variable oscillator for a PLL frequency synthesizer, the second local oscillation signal is generated by a high frequency oscillator in which its oscillation frequency is controlled based on the frequency control signal generated by the modulator to perform the orthogonal demodulation processing, and the third local oscillation signal is generated by a fixed oscillator in which its oscillation frequency is fixed.

Abstract: A broadcasting system discriminating television receiver including a circuit for evaluating the output of an FM demodulator, a circuit for evaluating the output of an I/Q wave detector, and a controller for controlling a switch based on the results of each evaluation. The switch is used primarily to determine whether the output of the receiver is analog or digital.

Abstract: A television signal tuning device having a memory which is adapted to store central frequency data for starting a synchronizing-signal detecting operation for all the channels and frequency division ratio data thereof. In a data presetting operation for each of the channels, a CPU causes a phase-locked loop circuit to perform a phase-locking operation for every data piece of the central frequency data or frequency division ratio data thereof which are stored in the memory for each channel. When the CPU detects a synchronizing signal from a video signal processing circuit in any one of the phase-locking operations which are successively performed by the phase-locked loop circuit, the CPU immediately renews the channel number and the tuning data thereof in the memory without performing the detection of an AFC variation. This feature greatly reduces the period of time required for the data presetting operation for each channel.

Abstract: A video detection unit is provided with a first control loop including a phase detector for comparing phases between the output of a voltage-controlled oscillator and the carrier of a VIF signal to output a control voltage, and a second control loop including a counter for measuring the output frequency of the oscillator to output a control voltage when the frequency is out of a predetermined range. The second control loop determines the free-run frequency of the oscillator. The first control loop makes the frequency and phase of the oscillator coincide with those of a carrier. The output of the counter is also used as an AFT voltage.

Abstract: An arrangement for receiving both TV and FM broadcast signals, particularly suited for multi-media applications. In the arrangement, a standard TV tuner (TUN) effects a first frequency conversion of an FM broadcast signal. A combination of a mixer (MP2) and an oscillator (VCO) effects a second frequency conversion of the FM broadcast signal. In order to keep the arrangement relatively simple, the oscillator (VCO) is included in a phase-lock loop (PLL), which is used for synchronous detection of a TV intermediate frequency signal. The phase-lock loop (PLL) includes a switch (SW) for deactivating the phase-lock loop (PLL) in the case of FM broadcast signal reception, such that the oscillator (VCO) is effectively free running.

Abstract: In an automatic frequency control circuit for synchronizing a horizontal deflection current of a television receiver with a horizontal sync signal, a bi-level signal which assumes either of two levels when the flyback pulse is or below a threshold value is produced, and a wider sync signal in synchronism with the horizontal sync signal and having a pulse width wider than the horizontal sync signal and equal to an odd multiple of the operating clock period is also produced. A phase comparator detects the difference in the number clock periods between a period period from a leading edge of the wider sync signal to an edge of the bi-level signal, and a period from the edge of the bi-level signal to a trailing edge of the wider sync signal. The detected difference is used to control a VCO. In an alternative configuration, a digital signal indicative of a magnitude of the flyback pulse during its rising or falling slope at an edge of the horizontal sync signal is produced and used for control of the VCO.

Abstract: A video signal frequency modulator having an automatic control function includes a reference generator for generating a sync tip level signal and a white peak level signal, a first switch for selecting one of the sync tip level signal, white peak level signal or a clamped video signal according to a mode control signal, a variable gain amplifier for amplifying the output of the first switch to a predetermined gain and converting the amplified result into a current, an adder for adding the output of the variable gain amplifier with a predetermined set value, an oscillator for frequency-modulating the output of the adder, a frequency detector for shaping and frequency-dividing the output of the oscillator, a microcomputer for comparing the output of the frequency detector with a predetermined reference frequency and outputting first and second control data and the mode control signal, a carrier frequency setting portion for controlling the magnitude of the predetermined set value according to the first control

Abstract: A device and method for auto fine tuning for a television or a VCR which carries out auto fine tuning using tuning data of a channel is provided. The AFC (Auto Fine Control) information detected in response to the AFT (Auto Fine Tuning) signal applied at the time of channel selection is used as the tuning data.Exact and easy determination upon detection of a synchronization signal for the tuning data of the center frequency at the time of initial tuning is facilitated because the determination on the detection of synchronization signal is carried out in the process for processing video signals and reception of clear image through optimum tuning because the fine tuning is carried out utilizing AFT level.

Abstract: An AFC filter for an FPLL comprises a filter formed of a network of resistors and capacitors exhibiting a predetermined phase response characteristic. The phase response characteristic is limited with increasing frequency to a value of about 90.degree. during a start-up interval.

Abstract: A broadcast signal receiver having improved sensitivity includes a tuner for tuning an RF signal input via an antenna to an IF signal of a specific channel, an IF signal processor for processing the IF signal output from the tuner to a video signal. A low noise amplifier is installed in front of the tuner for amplifying the RF signal and outputting the result to the tuner. The low noise amplifier has a noise figure lower than that of the tuner, to thereby enhance the noise figure of the overall system and the sensitivity of the receiver.

Abstract: In an automatic frequency control circuit for synchronizing a horizontal deflection current of a television receiver with a horizontal sync signal, a bi-level signal which assumes either of two levels when the flyback pulse is or below a threshold value is produced, and a wider sync signal in synchronism with the horizontal sync signal and having a pulse width wider than the horizontal sync signal and equal to an odd multiple of the operating clock period is also produced. A phase comparator detects the difference in the number clock periods between a period period from a leading edge of the wider sync signal to an edge of the bi-level signal, and a period from the edge of the bi-level signal to a trailing edge of the wider sync signal. The detected difference is used to control a VCO. In an alternative configuration, a digital signal indicative of a magnitude of the flyback pulse during its rising or falling slope at an edge of the horizontal sync signal is produced and used for control of the VCO.

Abstract: The present invention provides a method and device for locking onto a carrier signal located within a frequency band of a digitally modulated analog signal. More particularly, the method includes the steps of: dividing the frequency band into a plurality of segments, measuring a signal quality value for each of the segments, selecting one of the segments based on the measured signal quality values, and sweeping the selected segment using front-end circuitry in a receiver adapted to lock onto the carrier signal. The device according to an embodiment of the present invention includes a controller, a signal quality measurement unit, and a receiver including a front-end circuit. The controller executes a program that includes a first routine for dividing the frequency band into a plurality of segments. The measurement unit responds to the controller and measures a signal quality value for each of the segments.

Abstract: A high frequency television signal receiving apparatus providing excellent linear detection of output characteristics by improving the phase characteristic of the picture synchronous detector. A variable capacitive element is equivalently connected in parallel to a reference solid-state oscillation element. The reference solid-state oscillation element controls the frequency of a local oscillation device including a PLL circuit for feeding a local oscillation signal to a mixer for converting a high frequency signal into an intermediate frequency signal. A first low pass filter is connected between a phase comparator for detecting a phase difference of the intermediate frequency signal and the output of a detection oscillator for generating a detection oscillation signal with a specific phase difference. A second low pass filter having a larger time constant than the first low pass filter is connected to the variable capacitive element.

Abstract: A voltage controlled oscillator that completely eliminates the need for any externally mounted coil and capacitor, and an automatic fine tuning circuit for television which is inexpensive and highly accurate are provided.A first loop and a second loop are provided, said first loop for band-limiting an output signal of an amplifier through a bandpass filter to provide oscillation at a frequency of a resonant point of the bandpass filter, and said second loop for controlling the oscillation amplitude, so that a lowpass filter output with a 90.degree. phase is extracted from the first loop, while a bandpass filter output with a 0.degree. phase is extracted from the second loop.

Abstract: An HDTV receiver is disclosed including a tuning portion for selecting one of a plurality of RF signals received, and converting a selected RF signal into an intermediate frequency signal; a demodulator/FPLL for demodulating the intermediate frequency signal output from the tuning portion into a baseband signal in which the frequency and phase are locked, and outputting an AFC signal; a first local oscillator for forming a frequency signal which can be varied from a reference frequency to a specific frequency, and outputting the thus-formed frequency signal to the demodulator/FPLL; and a VSB filter for VSB-filtering the baseband signal output from the demodulator/FPLL.