JPS6258190B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention seeks to provide a circuit that can effectively extract only the common component of two input signals.

When trying to remove a ghost signal from a television signal containing ghost signals, it is necessary to set two antennas in slightly different directions to obtain two television signals each containing different ghost components, and then extract only the common component. By doing so, only the television signal from which ghost signals have been removed can be obtained.

Therefore, the present invention provides a circuit that can extract only the common component from two signals having such a common component and different components. This will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram thereof, FIG. 2 is a circuit diagram of a specific example thereof, and FIG. 3 is a waveform diagram thereof.

In the figure, 1 is an input terminal for a first input signal A, 2 is an input terminal for a second input signal B, and 3 is an output terminal for a common signal I. Also, 4, 5, 6 are
An AND circuit performs an AND operation on input signals in one direction (for example, positive direction) from a reference voltage, and an OR circuit performs an OR operation on input signals in the other direction (for example, negative direction). If OV is used as the reference voltage among the three sets of type 1 composite circuits that the company has, it is possible to use circuits in which four diodes are bridge-connected each as shown in FIG. The upper half constitutes an AND circuit, and the lower half constitutes an OR circuit. On the other hand, 7 is an OR circuit that performs an OR operation on input signals in one direction (for example, positive direction) from the reference voltage, and an AND circuit that performs an AND operation on input signals in the other direction (for example, negative direction). In the case of using OV as the reference voltage in a type 2 synthetic circuit having the following, a combination of six diodes as shown in FIG. 2 can be used. The upper half constitutes an OR circuit, and the lower half constitutes an AND circuit. Further, 8 is an amplifier circuit for compensating for signal loss in each of the above circuits, for example, a second amplifier circuit.
A complementary emitter follower amplifier circuit as shown in the figure can be used. Of course, this can be omitted if the loss is very small.

Then, the first input signal A from the input terminal 1 is applied as an input to the AND circuit and the OR circuit in the first and second type 1 combining circuits 4 and 5, and the second input signal A from the input terminal 2 is applied as an input. B is added as an input to the AND circuits and OR circuits in the second and third type 1 synthesis circuits 5 and 6, and the AND circuits and OR circuits in the first to third type 1 synthesis circuits 4 to 6 are input. Output C, D, E, F, G,
H is added as an input to the OR circuit and the AND circuit in the second type synthesis circuit 7, and the output I of the second type synthesis circuit 7 is amplified as necessary.
It is added as an input to the AND circuit and OR circuit in the seed synthesis circuits 4 and 6. The output of this second type synthesis circuit 7 is outputted to the output terminal 3 as a common signal.

Next, regarding the operation in such a configuration,
This will be explained with reference to FIG. First, input terminal 1,
Add input signals A and B to 2. Then, when the input signals A and B are equal as in range a, the waveforms appear as they are as outputs C to I of each circuit,
The waveform is output as the common signal I as it is.
Next, when either one of the input signals A and B does not exist at all as in range b, only a signal with the characteristics of one of them is outputted from the second type 1 synthesis circuit 5 to the output signals E and F. However, in the second type synthesis circuit 7, each signal is clamped to the level of the other signal, so the output signal I is not generated, and a no signal is output as the common signal I of both input signals A and B. Ru.

Furthermore, if a small signal such as a ghost signal or noise is superimposed on either of the input signals A or B, as in range c, and the input signals A and B differ slightly, the first to third The positive direction change portion and the negative direction change portion of these small difference portions are respectively removed by the first type combining circuits 4, 5, and 6 to generate output signals C to H, and the second type combining circuit 7 The remaining changing portion is removed at , and a sinusoidal output signal I, which is a common component of both input signals A and B, is obtained.

Thus, according to this circuit, only the signal common to the two input signals A and B can be extracted.

If such a circuit is used, by inputting television signals received by two antennas at different positions or directions as the two input signals, even if different ghost signals are included, they can be removed. Therefore, it is possible to obtain a television signal containing only common components and not including those ghost signals.

Furthermore, if the audio signals from the two microphones 9 and 10 with directivity as shown in Fig. 4 are added as the two input signals, an output signal that is sensitive only to the audio generated in the shaded area can be obtained. Obtainable.

Similarly, as shown in Figure 5, two directional antennas 1
By adding the received signals from 1 and 12, it is possible to obtain sharp directivity characteristics as shown by diagonal lines.

As described above, according to the present invention, it is possible to obtain an effective circuit that can effectively extract only the common component of two input signals.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a signal extraction circuit according to an embodiment of the present invention, Fig. 2 is its specific circuit diagram, and Fig. 3 is A, B, C, D, E, F, G, H, I.
is a waveform diagram for explaining its operation, and FIGS. 4 and 5 are characteristic diagrams showing examples of its application. 1, 2...Input terminal, 3...Output terminal, 4,
5, 6... First type synthesis circuit, 7... Second type synthesis circuit, 8... Amplification circuit.

Claims (1)

[Claims] 1. Three sets of first type synthesis circuits each having an AND circuit that performs an AND operation on an input signal from a reference voltage in one direction, and an OR circuit that performs an OR operation on an input signal in the other direction. a second circuit comprising an OR circuit that performs an OR operation with respect to an input signal in one direction from the reference voltage and an AND circuit that performs an AND operation with respect to an input signal in the other direction;
One set of seed synthesis circuits is provided, a first input signal is applied as an input to an AND circuit and an OR circuit in the first and second first type synthesis circuits, and a second input signal is applied as an input to the AND circuit and the OR circuit in the first and second first synthesis circuits. In addition, the output signal of the AND circuit in the first to third type first synthesis circuits is input to the OR circuit in the second type synthesis circuit. The output signals of the OR circuits in the first to third type 1 synthesis circuits are respectively added as inputs to the AND circuits in the second type synthesis circuit, and the OR circuits in the second type synthesis circuit are added as inputs. The combined output signal of the AND circuit is added as an input to the AND circuit and the OR circuit in the first and third type 1 combining circuits, and the common output signal of the first and second input signals from the second type combining circuit is added. A signal extraction circuit characterized in that it outputs signal components.