JPH04192887A - Ghost eliminating device for television receiver - Google Patents

Abstract

PURPOSE:To immediately display an image whose ghost is eliminated at the time when a TV receiver is operated by turning on a power source switch by deriving tap coefficient data for eliminating a ghost and storing it in a channel memory,even when the power source is turned off. CONSTITUTION:When a power source switch is turned off, a dri'ving power source is supplied to at least a tap coefficient control means, a channel memory 118, a coefficient data writing means and a channel switching control means. In such a state, when the power source switch is turned off, a tap coefficient corresponding to a channel designated by channel position data at every first channel is read out of the channel memory 118, and written in a waveform equalization TF83 and a regular ghost TF 130. That is, initial channel setting is executed. In such a way, when a TV receiver is operated by tuning on the power source switch, an image whose ghost is eliminated can be displayed immediately.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention uses a reference signal for a ghost canceller (hereinafter simply referred to as a GCR signal) included in the vertical blanking period, and performs transversal processing by a sequential correction method. Filter (hereinafter referred to as T
The present invention relates to a ghost removal device for a television receiver (hereinafter simply referred to as a TV receiver) in which ghosts are removed by a tap coefficient control means that determines a tap coefficient of a television receiver (hereinafter simply referred to as a TV receiver).

[Prior Art] Generally, ghost interference in a TV receiver is a phenomenon that occurs because desired waves are received multiple times due to reflection. If this multiplexed wave occurs in the form of linear addition, it can be removed by a TF provided inside the receiver. One possible method for removing ghosts using this TF is to use a vertical synchronization signal superimposed on a video signal.

That is, in principle, assuming that the vertical synchronization signal when there is no ghost as shown in FIG. 5(a) changes as shown in FIG. 5(b) due to the presence of a ghost.
By differentiating (difference) the leading edge of this vertical synchronizing signal, a differential pulse as shown in FIG. The ghost pulse GP corresponding to the ghost existing in the front and rear flat portions (approximately 30 microseconds) is used to cancel out the ghost. however,
The ghost removal method using such a vertical synchronization signal has the following problems.

■Since the falling characteristics of the leading edge are not strictly controlled, the characteristics vary depending on the transmitter and relay line, resulting in differences in the ghost improvement effect and insufficient performance.

■Since the synchronization signal is on the negative side of the pedestal level, it has poor correlation with the video signal that is on the positive side of the pedestal level. Especially in Japan, the modulation method of TV signals is 11VsB.
- Since it is AM, the amplitude of the carrier wave is maximum in the synchronization signal part, and the synchronization signal part is easily subject to nonlinear distortion in a high-power transmitter, resulting in a difference in ghost removal.

■Since the amplitude of the synchronization signal (e.g. 40 IRE) is about half of the maximum amplitude of the video signal (e.g. 100 IRE), S
/N ratio is not sufficient.

(2) Since analog COD was used for TF, non-linear characteristics of the element existed and sufficient improved characteristics could not be obtained.

While it was desired to solve the problems mentioned above, EDT V (Enhanced (or Ex
tended) Definition Te1evis
ion) (so-called clear vision), it has become possible to remove ghosts by using a tap coefficient control means that determines the tap coefficients of TF using a successive correction method using the GCR signal superimposed on the vertical blanking period. Ta.

The concept will be explained below using FIGS. 6 to 10.

(1) First, the concept of expanding the ghost detection range and removal range using the GCR signal included in the vertical blanking period will be explained.

The GCR signal is inserted into the 18th and 281st H of the vertical blanking period, and by using the 8-field sequence method, the synchronization signal, the signals of the lines before and after color burst signal 1, and these ghost components are canceled to detect the ghost. Make it possible to expand the range and removal range. That is,
On the transmitting side, based on the 5inX/X bar waveform shown in Fig. 6(a) and the pedestal waveform shown in Fig. 6(b),
The eight signal waveforms 81 to S shown in a) to (h) are created and transmitted, and the receiving side performs inter-field calculation using the following calculation formula (1), as shown in (i) in the same figure. Like GCR
Only the waveform of the signal Sgcr was extracted, making it possible to significantly expand the ghost removal range. For example, in Figure 7 (
The GCR signal S gcr shown in i) is converted into a clock pulse CK.
(For example, clock frequency 4F 5c (4F sc=
By one clock difference (differentiation) at 14.3 MHz), a differential pulse as shown in FIG. 80 μsec indicates the interference exclusion range.

Sgcr=(1/4)((S,-5,)+(S,-8,
)+ < S 3 S ? ) + (s * S
4) )...(1) In addition, Fig. 7 (a) to (h)
, "A+" represents the signal waveform of the 17th H, which has a color component phase of θ and is the line before the 18th H, and "A-"
” represents the signal waveform of the 17th H whose color component phase is θ+1806 and is the line before the 18th H, and “B0” represents the signal waveform of the 17th H whose color component phase is θ and which is the previous line of the 281st H.
It represents the 0H-th signal waveform, and "B-" indicates that the color component phase is θ.
280 which is +180' and the line in front of 281H
5 representing the H-th signal waveform, and also shown in FIG. 6(a).
The inX/X bar waveform has flat frequency components in the video frequency band, and high frequency components such as one-color ghosts can also be detected. Furthermore, the pedestal waveform shown in FIG. 6(b) is added for the purpose of preventing erroneous detection of a ghost when there is a ghost of a synchronization signal, a color burst, or a ghost of a long delay time.

(2) Next, the concept of removing ghosts using a tap coefficient control means that determines the tap coefficients of the TF using an iterative correction method will be explained.

The basic configuration is, as shown in FIG. 8, an adder 10, T F
20. The TF 20 consists of an error detection/tap coefficient control circuit 12 and a reference waveform generation circuit 14, and the TF 20 includes a minute time delay element (for example, a delay line) 22, . . . and a coefficient amplifier 2.
41,24□,...,24. and an adder 26. First, the operation when a ghost-free GCR signal as shown in FIG. 9(a) is input to the input terminal 30 will be described. At the start of ghost removal, the output of the TF 20 is zero as shown in FIG. 9(b), so the adder 26 outputs the input signal waveform of FIG. 9(a) as it is to the output terminal 32. Furthermore, the error detection/tap coefficient control circuit 12 compares the output signal of the adder 26 and the signal of the reference waveform generation circuit 14, and since there is no error, the tap coefficients of the coefficient amplifiers 241.24□, . . . , 24o C1, C
8,..., do not modify co. Therefore, the output of the TF 20 does not change as shown in FIG. 9(c), and the waveform of the GCR signal output to the output terminal 32 does not change as shown in FIG. 9(d). Next, the operation when a GCR signal with a ghost as shown in FIG. 10(a) is input to the input terminal 30 will be explained. At the start of ghost removal, the output of the TF 20 is zero as shown in FIG. 10(b), so the adder 26 outputs the input signal waveform of FIG. 10(a) as it is to the output terminal 32. Further, the error detection/tap coefficient control circuit 12 detects an error by comparing the output signal of the adder 26 and the signal of the reference waveform generation circuit 14, and uses coefficient amplifiers 241.24□,・・・
. , 24° tap coefficients C1, C, . . . , Crl are changed, respectively. Therefore, the output of the TF20 changes to a signal waveform, as shown in FIG. 10(c), in which only the ghost component in the input signal waveform of FIG. 10(a) is reversed,
The output of the output terminal 32 is outputted by the adder 26 to (a) and (
The signal obtained by adding the signals in c) changes into a clean GCR signal waveform without ghosts as shown in FIG. This output signal of FIG. 10(d) is again applied to the error detection/tap coefficient control circuit 12 together with the signal of the reference waveform generation circuit 14, but this time there is no error, so the respective tap coefficients C, C2, . ..., Cゎ is kept as is. In this way, a ghost-free GCR signal is reproduced from a ghost-containing GCR signal, and the same tap coefficients C and C are used until the next input GCR signal changes.
2,..., On is held and when the GCR signal changes, the tap coefficients C1, C2,...
・, Cn changes. By correcting all video signals with tap coefficients C, , C, .

As a ghost removal device for a TV receiver that utilizes the above-mentioned concepts (1) and (2), a device as shown in FIG. 11 has been considered. That is, among the television signals received by the antenna 40, tuned by the tuner 42, and amplified by the video IF amplifier circuit 44, the audio signal is transmitted to the audio engineer F amplifier circuit 46,
The video signal is output to the left and right speakers 54 and 56 via the audio detection circuit 48, the audio multiplexing and demodulation circuit 50, and the audio output circuit 52, and the video signal detected by the video detection circuit 58 is sent to the A/D (analog/digital) conversion circuit 60. , synchronous separation circuit 62,
The signal is input to the clock recovery circuit 64. A/D conversion circuit 60
The video signal converted into a digital signal is input to a D/A (digital/analog) conversion circuit 70 via a video signal processing unit 68 which is a digital processing stage for video signals provided in the control unit 66. The video signal converted into an analog signal by this D/A conversion circuit 70 is output to a CRT (cathode ray tube) 73 via a video output circuit 72. The video signal processing section 68 includes a shift register 74 as shown in FIG.
It is constructed by sequentially connecting adders 76 and 78 and a shift register 80. The video signal converted into a digital signal by the A/D conversion circuit 60 is further fed to a feed where the tap coefficients are collectively corrected so that the received GCR signal has a waveform equivalent to a reference GCR signal given in advance on the transmitting side. The signal is input to a waveform equalization TF 82 having a forward configuration, and the output of this waveform equalization TF 82 is input to an adder 76 in the video signal processing section 68 . A of the video signal processing section 68 further inputs the signal to a normal ghost TF 84 having a feedback configuration in which tap coefficients are successively corrected in the same manner as shown in FIG.

The output of this normal ghost TF 84 is input to an adder 78 in the video signal processing section 68. The waveform equalization TF 82 is used for waveform equalization including front ghosts, and the normal ghost TF 84 is used for normal ghost removal. As shown in FIG. 12, the control section 66 includes, in addition to the video signal processing section 68, an I10 control section 90 consisting of an I10 bus control section 86 and a memory control section 88, a DMA control section 92, and a DMA address generation section. The DMA processing unit 98 includes a DMA calculation processing unit 98 consisting of a calculation unit 94 and a calculation unit 96, an I10 control unit 100 for a channel selection CPU, and a timing generation unit 102. The control unit 66 includes a control bus 104.1.
06.107, address bus 108, data bus 110
The CPU 112 and the program ROM (includes a built-in ROM in which waveform data of the reference GCR signal is stored) 114. Work RAM (control unit 66 and CPU 11
2) 116, channel memory (memory for storing TF tap coefficients for each TV channel) 118, waveform RAM (18H1281H
memory for storing input/output waveforms of the GCR signal superimposed on) 120. The TF82.84 are combined.

These functions operate as follows, as shown in FIG. 13, through data processing mainly performed by the CPU 112 based on programs stored in the program ROM 114.

(a) When the power is turned on or when the power is turned on and the channel is switched, the tap coefficient corresponding to the channel specified by the channel position data is read from the channel memory 11g.

It is written to the waveform equalization TF 82 and the normal ghost TF 84.

(b) Next, by repeating the waveform capture using the DMA arithmetic processing section 98 and the computation by the CPU 112 a predetermined number of times, a GCR signal with reduced noise is obtained, and this GCR signal is captured as an initial waveform.

(C) When the channel memory 118 is not used and is cleared, ghosts at a long distance (in the range of 24 to 40 psec) are detected, and the next waveform equalization operation is started, and the channel memory 118 is cleared. is used, the process moves on to the next waveform equalization operation without detecting a long-distance ghost.

(d) For waveform equalization operation, input G to waveform equalization TF82
The waveforms of the CR signal and the output GCR signal from the waveform equalization TF 82 are loaded into the waveform RAM 120, and the GCR signals before and after equalization are obtained by calculation using the same 8-field sequence method as described in (1) above. .

(e) Next, the GCR signal obtained in the above (d) is differentiated, the peak position is detected from the input GCR signal, and this is used as a reference when correcting the tap coefficient. Then, the peak position after equalization is calculated from this peak position, and the program ROM 11
An error signal is obtained by performing subtraction with the reference signal in 4.

(v) Then, by using the tap coefficient control means similar to that described in (2) above, the tap coefficient correction amount is determined by correlation calculation, which is the most stable among the sequential calculation control methods. That is, first, in order to shorten the convergence time, the tap coefficient correction amount is determined by proportional control shown in the following equation (2). Next, when the ghost is considerably reduced by proportional control, the following formula (3
) Continuous ghost removal operation is performed by constant incremental control as shown in ). As a result, stable control characteristics can be obtained even under a low S/N ratio, and very slow ghost fluctuations can be followed.

Ci, new=CLold-a ・ΣXk-E 1
・(2) Ci, new= Ci, old−Δ・Sgn(
ΣXk - El) (3) Here, Ci indicates the first tap coefficient, the subscripts new and old indicate after and before modification, respectively, and
) is the error signal, and α and Δ are positive minute amounts.

(g) When the operations (d) to (f) above reach a predetermined number of times, the tap coefficient data in the channel memory 118 is updated, and new data is always held.

(H) The operations (A) to (G) above are performed every time the channel is switched.

``Problems to be Solved by the Invention'' However, in the ghost removal device for a TV receiver shown in FIG. 4Fsc (4Fsc =
14.3MHz)), and ghosts were removed by controlling coefficients for each tap of the TF, which resulted in the problem that the required number of TF taps became large (for example, approximately 640 taps), resulting in high costs. There was a point. That is, since the current price of one TF with 64 taps is about 2,000 yen, the price of a TF with 640 taps has increased to about 20,000 yen.

The present invention was made in view of the above-mentioned problems, and it is an object of the present invention to provide a ghost removal device for a TV receiver that can reduce the required number of TF taps.

"Means for Solving the Problem" The present invention inserts a transversal filter into the digital processing stage of the video signal, detects the waveform of the GCR signal included in the vertical blanking period affected by ghost, A ghost component is detected by comparing this detected waveform with a reference GCR signal waveform that is not affected by ghosts,
In the television receiver, ghosts are removed by tap coefficient control means that determines tap coefficients of the transversal filter so that detected ghost components are minimized by a successive correction method, wherein the tap coefficient control means The tap coefficient of the transversal filter is determined for each section in which the ghost removal range of the signal is divided into a plurality of sections, and the device is independently readable and writable for storing video data from which ghosts have been removed by the transversal filter. Video data writing control that provides an image processing memory and writes video data from which ghosts have been removed by the transversal filter into a corresponding area of the image processing memory based on tap coefficients determined for each section by the tap coefficient control means. provide means,
A channel memory is provided for storing tap coefficient data for each channel, and coefficient data write control means is provided for writing the tap coefficient data determined by the tap coefficient control means into the channel memory, and the coefficient data writing control means is provided for writing the tap coefficient data determined by the tap coefficient control means into the channel memory, and A channel switching control means for switching the selected channel is provided, and an off-time power supply means is provided for supplying driving power to the tap coefficient control means, the channel memory, the coefficient data writing control means, and the channel switching control means in response to a power off detection signal. It is characterized by the fact that

[Operation] The tap coefficient control means determines the tap coefficient of the TF for each section in which the ghost removal range of the GCR signal is divided into a plurality of sections. The video data writing control means writes the video data from which the ghost has been removed by the TF into the corresponding area of the image processing memory for each section of the ghost removal range based on the tap coefficient determined by the tap coefficient control means. The video data written in this image processing memory is read out at a timing independent of the writing timing (for example, at the timing of a synchronization signal) and output to the display section.

In this way, the ghost removal range is divided into multiple sections, and a tap coefficient is determined for each section.

Since the video data from which ghosts have been removed based on the tap coefficients is written to an independently readable/writable image processing memory, the number of taps required for the TF can be reduced to one-fold of the conventional number.

Moreover, when the power is turned off, the tap coefficient control means, channel memory, coefficient data writing control means, and channel switching control means are supplied with driving power by the off-time power supply means, so the tap coefficient control means operates and the tap Tap coefficient data for each channel determined by the coefficient control means is written into the channel memory. Therefore, when the power switch is turned on and the TV receiver is activated, the image from which ghosts have been removed can be immediately displayed.

[Embodiment] FIGS. 1 to 4 show an embodiment of the present invention, and in these figures, the same parts as in FIGS. 5 to 12 are designated by the same reference numerals. Description of the same parts in FIG. 1 as in FIG. 11 will be omitted. In FIG. 1, reference numeral 130 is a normal ghost TF that is made relatively smaller than the TF 84 in FIG. 11 (for example, the number of taps is 64, which is one-tenth). The control unit 66 sends the normal ghost T F 13
A data input side of a dual port RAM 132, which serves as an independently readable/writable image processing memory for storing video data, is coupled to the data bus for transmitting video data to the data bus. The dual port RAM 1
A D/A conversion circuit 70 is coupled to the data output side of 32.

That is, the configuration is such that a dual port RAM 132 is inserted before the D/A conversion circuit 70 shown in FIG. A video output switch 134 is inserted into the line that transmits the output signal from the D/A conversion circuit 70 to the video output circuit 72. An audio output switch 13 is provided on the line that transmits the signal from the video IF amplifier circuit 44 to the audio IF amplifier circuit 46.
5 has been inserted. 136 is the program R in Figure 11
A program ROM 138 stores a program that is the main program stored in the OM 114 plus a program specific to the present invention;
C that performs predetermined data processing based on 36 programs
It is PU.

Next, the operation of the embodiment described above will be explained with reference to the drawings from FIGS. 2(a) to 4(b). The following data processing such as calculation and control is performed based on a program stored in the program ROM 136.

(b) The on/off state of the power switch is detected by a general-purpose power on/off detection means. Based on this power on/off detection signal, the on/off control means turns on/off the video output switch 134 and the audio output switch 135. Note that the video output switch 134 and the audio output switch 135 are mechanically linked to the power switch and turned on and off.
The channel switching control means, which may be turned off, sequentially switches the channel selected by the tuner 42 at every set time based on the power off detection signal. Further, even when the power switch is turned off, drive power is supplied to each circuit on the preceding stage of the video output switch 134 and the audio output switch 135 of the TV receiver to enable operation, based on the power off detection signal. When the power supply switch is turned off, driving power is supplied to at least the tap coefficient control means, the channel memory 118, the coefficient data writing means, and the channel switching control means. If the channel switching control means switches channels at set time intervals while the power switch is off, or if channels are switched by the remote control or manually while the power switch is on, In either case, the tap coefficient corresponding to the channel specified by the channel position data for each channel is initially stored in the channel memory 118.
and written to the waveform equalization TF 82 and the normal ghost TF 130. That is, initial channel setting is performed. Hereinafter, unless otherwise specified, it is assumed that the same operation is performed regardless of whether the power switch is on or off.

(b) Next, by repeating the waveform capture using the DMA arithmetic processing section 98 and the calculation by the CPU 138 a predetermined number of times, a GCR signal with reduced noise is obtained, and this GCR signal is captured as the initial waveform.

(c) When the channel memory 118 is not used and is cleared, the detection of a ghost at a long distance (in the range of 24 to 40 μsec) is performed before the next first... When the second waveform equalization operation is started and the channel memory 118 is being used, the next first and second waveform equalization operations are performed without detecting a long-distance ghost.

(d) The first waveform equalization operation is performed by inputting the input GCR signal to the waveform equalization TF82 and the output GCR signal from the waveform equalization TF82.
The signal waveform is loaded into the waveform RAM 120, and the above (1)
The pre-equalization and post-equalization GCR signals are obtained by calculation using the 8-field sequence method similar to that described in .

(e) In the second waveform equalization operation, as shown in FIG. A predetermined clock pulse CK (for example, clock frequency 4 F
5c (4F 5c==14.3MHz)). That is, for modification category (■), the GCR signal S g obtained in (d) above
cr is differentiated, the peak position is detected from the input GCR signal, and this is used as a reference when modifying the tap coefficient. Then, the equalized peak position is calculated from this peak position, and subtracted from the reference signal in the program ROM 136 to obtain an error signal.

(v) Then, by using the tap coefficient control means similar to that described in (2) above, the tap coefficient correction amount is determined by correlation calculation, which is the most stable among the sequential calculation control methods. That is, first of all, in order to shorten the convergence time, the above-mentioned calculation formula (
The tap coefficient correction amount is determined by the proportional control shown in 2). Next, if the ghost is significantly reduced by proportional control,
Continuous ghost removal operation is performed by constant incremental control shown by the above-mentioned arithmetic expression (3).

(g) Each time the operations (d) to (f) above reach a predetermined number of times, the coefficient data write control means writes the tap coefficient data determined by the tap coefficient control means into the corresponding area in the channel memory 118. The data is updated and new tap coefficient data is always held. The tap coefficient data determined by the tap coefficient control means is written into the T F 130 regardless of whether the operations (d) to (f) have reached a predetermined number of times. Also.

The video data from which the ghost has been removed by the T F 130 is written by the video data write control means into an area corresponding to section (2) in the dual port RAM 132, as shown in FIG.

(H) Next, the same operations as in (E) to (G) above are performed for the ghost removal range (■) by the GCR signal S gcr, the tap coefficient correction amount is determined, and the corresponding area in the channel memory 118 is will be written to. And based on this modified tap coefficient < T F 13
As shown in FIG. 4, the video data from which ghosts have been removed by 0 is written into the area corresponding to section 2 in the dual port RAM 132.

Hereinafter, tap coefficient correction amounts are similarly determined for the ghost removal range (2), . . . Data is written to the areas corresponding to the sections (2), . . . , [phase] in the dual port RAM 132, as shown in FIG.

(i) When the power switch is off, the channel switching control means switches the channel of the tuner circuit 42 every time the set time set for channel switching elapses, and for each channel,
The same operations as in ~(h) are performed. In addition, if the power switch is on, each time the channel is switched using the remote control or manually, the
The same operations as a) to (ch) are performed.

"Effects of the Invention" As described above, the ghost removal device for a TV receiver according to the present invention determines the tap coefficient of the TF for each section in which the ghost removal range is divided into a plurality of sections, and removes the ghost based on this tap coefficient. Since the video data is written to the corresponding area of the image processing memory that can be read and written independently, the number of taps required for the TF can be reduced to one-fold compared to the conventional one, thereby reducing costs. I can do it.

For example, when the ghost removal range is divided into 10 sections, the number of taps required for the TF is reduced from 1 to 1 (640, for example).
It can be reduced to 1/0.

Moreover, even when the power is off, the tap coefficient control means
Drive power is supplied to the channel memory, coefficient data writing control means, and channel switching control means, and tap coefficient data for ghost removal is obtained and stored in the channel memory.Turn on the power switch and turn on the TV receiver. When activated, the ghost-removed image can be displayed immediately.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the ghost removal device for a TV receiver according to the present invention, FIG. 2 is a flowchart explaining the operation of FIG. 1, and FIG. 3 is a GCR signal S get
and clock pulse GK, FIG. 4 is an explanatory diagram explaining writing to dual port RAM, FIG. 5 is a waveform diagram explaining the concept of ghost removal method using vertical synchronization signal, and FIG. ), (b) and Figure 7 (a) to (j)
are waveform diagrams to explain the concept of the 8-field sequence method, Figures 6 (a) and (b) are waveform diagrams showing the 5inX/X bar waveform and pedestal waveform, and Figures 7 (a) to (h).
) is a waveform diagram of eight signals created based on the signals in Figures 6(a) and (b) and used in the 8-field sequence method, and Figure 7(i) is a waveform diagram of the 8 signals extracted by the 8-field sequence method. GCR signal S gcr waveform diagram, Fig. 7 (j) is the 7th
Waveform diagrams obtained by subtracting the waveform of Fig. (i) by one clock using clock pulse GK, and Figs. This explains the concept of removing ghosts. Figure 8 is a block diagram showing a typical basic configuration, and Figures 9 (a) to (d) are diagrams of Figure 8 when a ghost-free GCR signal is input. Waveform diagrams for explaining the operation; Figures 10 (a) to (d) are waveform diagrams for explaining the operation of Figure 8 when a ghost-free GCR signal is input; Figure 11 is for a conventional TV. FIG. 12 is a block diagram showing the ghost removal device of the receiver, FIG. 12 is a block diagram showing the control section of FIG. 11, and FIG. 13 is a flowchart explaining the operation of FIG. 11. 12...Error detection/tap coefficient control circuit, 14...
Reference waveform generation circuit, 20.130...TF (transversal filter), 68...Video signal processing section (digital processing stage of video signal), 112.138...CP
U, 114, 136...Program ROM, 118.
...Channel memory, 132...Dual port R
AM (image processing memory), 134...Video output switch, 135...Audio ratio switch, CK...Clock pulse, GCR signal...Ghost canceller reference signal, S gcr...GCR signal waveform. Applicant: Fujitsu General Ltd. Patent Attorney: Kano 5 ″

Claims (2)

[Claims] (1) A transversal filter is inserted into the digital processing stage of the video signal, detects the waveform of the GCR signal included in the vertical blanking period affected by ghosts, and removes this detected waveform from the effects of ghosts. A ghost component is detected by comparing it with a reference GCR signal waveform, and the ghost is removed by a tap coefficient control means that determines the tap coefficient of the transversal filter so that the detected ghost component is minimized by a successive correction method. In the television receiver, the tap coefficient control means comprises:
The ghost removal range of the GCR signal is divided into a plurality of sections, and the tap coefficients of the transversal filter are determined for each section. video data from which ghosts have been removed by the transversal filter based on the tap coefficients determined for each section by the tap coefficient control means, and which are written into corresponding areas of the image processing memory; A write control means is provided, a channel memory is provided for storing tap coefficient data for each channel, a coefficient data write control means is provided for writing tap coefficient data determined by the tap coefficient control means into the channel memory, and the power is turned off. A channel switching control means is provided which switches the selected channel at each set time based on a detection signal, and a power off detection signal supplies driving power to the tap coefficient control means, channel memory, coefficient data writing control means, and channel switching control means using a power off detection signal. What is claimed is: 1. A ghost removal device for a television receiver, characterized in that it is provided with a time power supply means. (2) The ghost removal device for a television receiver according to claim 1, wherein the tap coefficient control means determines the tap coefficients by correlation calculation, which is the most stable among sequential calculation control methods.