JPS6022805A - Automatic directivity changeover antenna device - Google Patents

Abstract

PURPOSE:To select automatically the optimum directivity by providing a means detecting the reception frequency changeover and restarting the sequential changeover to an automatic directivity changeover antenna device. CONSTITUTION:When a defeat pulse generated at the channel changeover from a television receiver is inputted to a terminal 10, a frequency-dividing circuit 12 is reset, and a clock signal CK from a main block generating circuit 7 inputted via a switch circuit 9 is frequency-divided and frequency-divided outputs D0, D1 and D2 are transmitted to a decoder 13. A control circuit 14 receives an output of the decoder 13 so as to control sequentially the changeover of the antenna directivity. When a minimum noise component of a composite video signal from the television receiver is detected, a best point detecting circuit 8 closes the switch circuit 9 so as to inperrupt the clock signal CK transmitted to the frequency division circuit 12. Thus, the optimum directivity of the antenna is selected automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic directivity switching antenna device that can be used as an indoor antenna for a television receiver or the like.

Conventional configuration and its problems Generally, television signals are received using an indoor antenna.
Z, ), l'! ,,j, the directivity must be changed by changing the direction or the configuration of the antenna element depending on the channel to obtain the best image, which is very inconvenient.

Recently, as shown in FIG. 1, indoor antennas have been commercially available in which the connection of a plurality of antenna elements A is changed by a rotary switch S to change the directivity and select a point that produces the best image. However, it is inconvenient because it is necessary to select the optimum directivity each time the channel is switched.

Furthermore, in a television receiver that uses a channel remote control, the antenna must be operated even when changing channels from a distance, which eliminates the convenience of the remote control.

Furthermore, due to antenna operation, reception conditions often change depending on when a person approaches the antenna and when the person moves away from the antenna, making it difficult and inconvenient to adjust the antenna.

OBJECT OF THE INVENTION The present invention solves the above-mentioned problems, and is designed to obtain the optimum received signal by automatically changing the directivity of the antenna at the same time as changing the receiving frequency of the receiver and also when the power is turned on. The purpose of this invention is to provide an automatic directivity switching antenna device.

Structure of the Invention The automatic directivity switching antenna device according to the present invention automatically switches the directivity by switching the combination of a plurality of antenna elements when a receiving frequency (channel) of a receiver such as a television receiver is selected. , Receive the reception status at each directivity.1. - It detects the noise component in the signal and selects the directivity that minimizes the noise component.Furthermore, the directivity can be automatically switched even when the power is turned on. Frequency switching is detected, and the detection output is used to sequentially switch antenna combinations and to achieve the above-mentioned directivity.

DESCRIPTION OF EMBODIMENTS First, FIG. 2 shows a diagram illustrating an example of the configuration of an antenna element and the direction of directivity. Figure 2 (shown in al, Vρ, a
Place the linear antenna -d as shown in the figure. By using antennas a and C arranged in this way, the directivity can be set in the directions 3 and 7 in Fig. 2 (bl), and by using antennas b and d, the directivity can be set in the directions shown in Fig. 2 (b). Directivity can be changed in directions 1 and 6. By combining antennas a and d in this way, the directivity can be changed.

Next, FIG. 3 shows a system block diagram of an embodiment of the present invention. The operation of the present invention will be explained with reference to FIG. First, a plurality of antenna elements 1 are connected to a switching circuit 2 (f).The antenna outputs appropriately combined by this 5 are supplied as human power to the television receiver 3. The signal (composite video signal) is guided to the best point detection circuit 4, which detects noise components including ghosts in the composite video signal.

This detection signal is added to a switching circuit 2 for the combination of antenna elements 1 and a control circuit 5 controlling it, and the level of the detection signal is determined while changing the combination of antenna elements 1. A combination of elements is selected from a plurality of combinations and that combination is fixed.

Furthermore, when switching channels or turning on the power, the reset circuit 6 uses pulses generated when switching channels in the television receiver 3 to repeat the above series of operations.
works.

The reset circuit and control circuit section, which is one of the most significant features of this device, will be explained with reference to a configuration example of the cent circuit 6 and control circuit 5 in FIG. 4 and basic control pulse waveforms in FIG. 6.

1. When a defeat pulse (a reset pulse generated when switching channels) is input from the television receiver 3 to the switch circuit 9 from the terminal 1o in FIG. 4, the frequency divider circuit 12 is reset by the defeat pulse. At the same time, a main clock signal as shown in FIG.
The signal is input to the frequency dividing circuit 12. Also, at this time, the switch circuit 9
A predetermined switching voltage is applied from a terminal 11 to the main clock signal a, which is configured to pass the main clock signal a to a frequency dividing circuit 12.

Next, the main clock signal a is passed to the sixth clock by the frequency dividing circuit 12.
The frequency is divided into pulses as shown in the figure (bl, fc) and (di. These frequency-divided outputs b, c, and d are decoded into several types of pulses by the decoder circuit 13, and then sent to the RF switch control circuit 14. added to.

Here, the output 16 of this RF switch control circuit 14 is connected to the switching circuit 2 shown in FIG. 3, and the combinations of a plurality of antennas are automatically switched sequentially.

Therefore, when the best combination of multiple antennas is detected, a stop pulse is sent to the switch circuit 9 from the best point detection circuit 8 in FIG. The structure is such that it blocks out a.

The above explanation is a method for automatically detecting the best combination from among multiple antenna combinations when a Diffie 1 pulse is received from the TV receiver 3. A method of changing the combination of antennas for each foot pulse will be explained.

First, in this case, the switching voltage of the terminal 11 in FIG. 4 is applied to the switch circuit 9 as a voltage opposite to that in the case of automatic selection described above. That is, this voltage causes the switch circuit 9
The main clock signal a entering the frequency dividing circuit 12 via the main clock signal a is cut off. Next, in this state, the defeat pulse is sent from the television receiver 3 to the switch circuit 9 from the terminal 10 in FIG.
When the pulse is input to the frequency dividing circuit 12, this pulse becomes the input pulse to the frequency dividing circuit 12. That is, the first frequency of the defeat pulse e as shown in the divided output waveform of the defeat pulse in FIG.
The th pulse "(11") passes through the switch circuit 9,
6 (fl
, +gl, (hl) is set at the "'1" position of i+, and
When the first pulse "(1)" is input, the antenna combination moves to the "2" position of (1).Subsequently, the second pulse "(2)" is input. , the antenna combination moves to the 10″3″ position,
Similarly, the combination of antennas can be changed every time a defeat pulse is received.

Effects of the Invention As described above, according to the present invention, when the reception frequency of a channel etc. is switched, the best combination can be automatically selected from among a plurality of antenna combinations, and the defect from the receiver can be automatically selected. It is possible to sequentially advance the combination of antennas for each pulse, and it is possible to set the combination at the position of one's preference, making it possible to obtain something very convenient.

[Brief explanation of drawings]

Figure 1 is a block diagram of a conventional antenna switching device, and Figure 2 is a block diagram of a conventional antenna switching device.
Figures a and b are a plan view and a characteristic diagram of the antenna for directivity switching, Figure 3 is a block diagram of an automatic directivity switching antenna device according to an embodiment of the present invention, and Figure 4 is a reset circuit used in the device. and a block diagram of the control circuit, and FIGS. 5 and 6 are waveform diagrams illustrating its operation. 1. Antenna element, 2. Switching circuit, 3.
...TV receiver, 4...Best point detection circuit, 5...Control circuit, 6...Reset circuit, 7...Main Clock generation circuit, 9.
...Switch circuit, 12... Frequency divider circuit,
13, --- Decoder, 14, RF switch control circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] means having a plurality of antenna elements and switching combinations of the antenna elements; means for supplying the switched output to a receiver; means for detecting a noise component in a signal received by the receiver; means for detecting the point at which the noise component is minimum; means for controlling the switching of the combination of the antenna elements; means for controlling the control means using the detection output of the noise component minimum point; and means for detecting the switching of the reception frequency and performing the control operation. An automatic directivity switching antenna comprising means for automatically restarting, means for sequentially switching the antenna combination using an output that detects the reception frequency switching, and means for switching between the automatic control and the sequential control. Device.