JPS6022806A - Automatic directivity changeover antenna device - Google Patents

Abstract

PURPOSE:To maintain the reception of a television receiver in the best condition by providing a means detecting the change of either reception frequency changeover or reception state and restarting the directivity changeover control to an automatic directivity changeover antenna device. CONSTITUTION:A best point detecting circuit 4 receives a composite video signal from a television receiver 3 and detects the noise component including ghost. A control circuit 5 changes over the directivity of an indoor antenna 1 by a changeover circuit 2 so as to minimize the detected output. An automatic reset pulse generating circuit 7 stores a detected output of the best point detecting circuit 4 when the optimum directivity is obtained, compares the detected output with the new detected output and when the result of comparison exceeds a prescribed level, and transmits a pulse to a reset circuit 6. The reset circuit 6 receives this pulse, resets the control circuit 5 and the best point detecting circuit 4 and starts the re-control. Further, the reset circuit 6 conducts said operation also by a channel changeover pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a device for automatically switching the directivity of an antenna used in a television receiver or the like.

Conventional configurations and their problems In general, when receiving TV waves with an indoor antenna, the directionality of the antenna is changed by changing the direction or shape of the antenna element depending on the channel to achieve the optimal image condition. This operation was very troublesome and inconvenient for viewers.

However, recently, indoor antennas such as the one shown in Figure 1 have been commercially available that allow you to change the antenna directivity among several types by switching the connection of multiple antenna elements with a rotary switch S, and select the best reception condition while looking at the image. has been done. However, in this case as well, there is still the hassle of switching between the channels each time the channel is changed, which is inconvenient.

Furthermore, recently, IJ has been changing the channel floor of the TV receiver.
The number of channels that can be operated using remote control is increasing, and when receiving this channel remote control using an indoor antenna, it is necessary to switch channels and antennas, which reduces the convenience of the channel remote control by half. This is K.

Furthermore, the reception condition often changes depending on whether a person approaches the antenna to switch antennas or moves away from the antenna after switching, so manually switching antennas is cumbersome and difficult. It is a simple operation.

Purpose of the Invention The present invention solves the above-mentioned conventional inconveniences and problems, and at the same time as selecting the receiving frequency (channel), the antenna directivity is automatically switched between several types to obtain the optimal directivity. The purpose of the present invention is to provide a device that can select a reception frequency and maintain a good reception condition. , while automatically switching the antenna directivity among several types, the size γ included in the received signal of the receiver is
), -C Noise component 4 - Detect and select the directivity with the least noise component from several types of directivity, and if the reception condition deteriorates even with the selected direction, it will automatically start again. DESCRIPTION OF THE EMBODIMENT OF THE INVENTION A block diagram of an embodiment of the present invention is shown in FIG. 2. First, a plurality of antenna elements 1 are connected to a switching circuit 2. As shown in FIG. Here, the signals received by the appropriately combined antenna elements are supplied as antenna power to the television receiver 3.
Ru. The composite video signal detected by the receiver 3 is guided to the best point detection circuit 4, which detects noise components including ghosts in the composite video signal. This output is supplied to the control circuit 5 that controls the switching circuit 2, and when the best point is selected, the switching circuit 2 is fixed in that state.

This control loop is useless when the TV receiver is turned on.
Channel 1 from the TV receiver so that it works when ... and when you select a channel. /J switching pulse is supplied to the reset circuit 6.

Next, the automatic pulse generation circuit 7, which is a feature of this device, will be explained. Even if the best point detection circuit 4 memorizes the voltage with the least noise and selects the best directivity, the state of the radio wave changes over time, and the noise voltage may vary from the memorized voltage. If it becomes worse, a pulse is generated at that point, and the
A pulse is supplied to the J-node circuit 6 to select the directivity again.

FIG. 3 shows a schematic diagram of one embodiment of the automatic resenotonoculus generation circuit 7. One input is the noise voltage detected by the best point detection circuit 4, and one is led to the storage circuit 8, which stores the noise voltage at the best point. This memorized electricity)i
i is supplied to the level shift circuit 9 and its output becomes the reference voltage of the comparator 10. The zero noise voltage is further supplied to the comparator 1.
0 is supplied as the other human power. In the comparator, when the reference voltage and the noise voltage match,
From the noise Ichikawa at the time of the initially selected antenna directivity, the level shift circuit 9 generates a response and supplies it to the reset circuit 6.
□1 (When the noise voltage gets worse, the automatic reset becomes 1 level and 2.) This level shift amount can be selected at will.

Thus, when the reception condition becomes poor, the directivity can be reselected and the directivity of the good reception condition can be maintained.

Effects of the Invention As described in Section 2, according to the present invention, the antenna directivity switching operation, which was conventionally inconvenient and undesirable, can be performed automatically when a reception frequency (channel) is selected, and it is convenient for viewers. Furthermore, when the reception condition worsens due to changes in time, etc., the viewer must constantly operate the antenna in order to make the selection. It is possible to have a good reception condition without thread 1 (0

[Brief explanation of the drawing]

FIG. 1 is an 11-plane view showing an example of a conventional indoor antenna, FIG. 2 is a block diagram of an automatic directivity switching antenna device according to an embodiment of the present invention, and FIG. FIG. 2 is a block diagram of a resenotonoculus generation section. 1...Antenna element, 2...Switching circuit,
3... - chimp receiver, 4... best point detection circuit, 6... control circuit, 6... reise throat circuit, T...
...Automatic 1"Cenotobalus Cow Circuit 1.゛8-...
・-2 circuit, 9... rail shift circuit-IC)
・Comparison circuit O

Claims (1)

[Claims] means having a plurality of antenna elements and switching combinations of these antenna elements; means for supplying the output thereof to the receiver; means for detecting the best point of the signal image condition of the receiver;
means for controlling combination switching of the antenna elements by the best point detection output; means for detecting reception frequency switching in the receiver and restarting the switching operation;
An automatic directivity switching antenna device comprising: means for detecting a change in the reception state at the best point; and means for restarting the switching operation based on the reception state change detection output.