JP3467804B2 - Diversity receiving apparatus and method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diversity receiving apparatus and method applied to an in-vehicle liquid crystal television set or the like.

[0002]

2. Description of the Related Art In a receiving device such as a vehicle-mounted liquid crystal television device whose receiving state changes moment by moment, a diversity function for automatically selecting and selecting the best receiving state from a plurality of receiving antennas is mounted. This enables more stable reception.

FIG. 4 shows a system configuration of a conventional television receiver equipped with a diversity function. This figure shows a system configuration in which the television receiver main body and the diversity unit are separated, and these may be integrated.

In the figure, 11 is a television receiver main body, 12 is a diversity unit, and 13 is a plurality of receiving antennas. The diversity unit 12 includes a plurality of receiving antennas 13
An RF switch circuit 14 for selectively switching between, a sample hold circuit (denoted as "SH" in the figure) 15, a comparator (denoted as "CMP" in the figure) 16 and a controller 17.

The RF switch circuit 14 switches and selects one of the plurality of receiving antennas 13 under the control of the controller 17, and supplies the RF signal a of the received radio wave to the television receiver body 11. Then, the video signal b output from the video output terminal of the television receiver main body 11 is sequentially sampled by the sample hold circuit 15, and the comparator 16 outputs the signal c (c1, c2) indicating the reception level of the reception antenna.
Sent to. In the comparator 16, the two reception level signals c1 and c2 sent from the sample hold circuit 15 are received.
Are compared, and the comparison result d is sent to the controller 17. The controller 17 outputs a selection signal e to the RF switch circuit 14 according to the comparison result d from the comparator 16 to control the switching selection operation in the switching signal RF switch circuit 14.

In the above configuration, the sample hold circuit 15 samples and selects the horizontal synchronizing signal in the vertical blanking period in the video signal b from the television receiver body 11 for each field. While holding the input as the reception level X of the reception antenna, the controller 22
The reception level Y of the reception antennas that have not been sequentially selected is input and held in synchronization with the switching selection of the reception antennas 13 by the RF switch circuit 14 according to the selection signal e output from. The reception levels X and Y are sequentially compared as reception level signals c1 and c2 by the comparator 16, and the controller 17 outputs the selection signal e according to the comparison result d, so that the higher reception from the reception antenna 13 is performed. The receiving antenna of the level is switched and selected by the RF switch circuit 14.

[0007]

However, in the above-described conventional television receiver system equipped with the diversity function, when the television receiver main body 11 side issues a tuning instruction during the comparison process by the comparator 16, The horizontal synchronizing signal disappears in the video signal b due to the channel selection operation, and as a result, the channel selection operation is performed with the receiving antenna selected immediately before the channel selection instruction is selected. .

Therefore, the channel having the highest reception level is not always selected, and there is a possibility that the channel which should be able to be received is skipped and reception becomes impossible.

The present invention has been made in view of the above circumstances, and its purpose is to provide tuning accuracy.
It is to provide a diversity receiving apparatus and method capable of improving

[0010]

That is, the present invention has a plurality of
Each antenna input given from the antenna of
The switching selecting means for performing the selecting operation, and the switching selecting means
The antenna selection means for comparing the reception levels of the respective antenna inputs that are selected more sequentially and selected to select the antenna input of the best reception level, the tuning control means for executing the tuning operation, and the start of the tuning operation by this tuning control means Instructing means for instructing and the switching selection
During the switching selection operation of each antenna input by the selecting means,
When the tuning means is instructed by the indicating means
Even if, the antenna input of the best reception level selected by the antenna selection means is used as the antenna input for the tuning operation by the tuning control means.
It is obtained so as to include an antenna control means for selecting. Also, a detection means for detecting the execution of the tuning operation by the tuning control means, the switching換選
Selection means performs the switching selection operation at a predetermined cycle, and the antenna control means controls each switching selection means.
When the execution of the tuning operation is detected by the detection means during the switching selection operation of the tenor input, the current switching selection operation by the switching selection means is stopped, and the antenna selection is performed in the previous switching selection operation by the switching selection means. The antenna input of the best reception level selected by the means may be selected as the antenna input for the tuning operation by the tuning control means. Further, the detection means includes means for detecting the end of the tuning operation by the tuning control means, and the antenna control means has the switching selection operation by the switching selection means until the end of the tuning operation is detected by the detection means. May be stopped. The front Symbol tuning control means starts the tuning operation when the start of the tuning operation is instructed by said instructing means, said switching selection means, the predetermined period of the switching selection operation
Performed every, the antenna control unit, the switching selection hand
When the tuning means is instructed to start the tuning operation during the switching selection operation of each antenna input by the step, the current switching selection operation by the switching selection means is stopped and the previous switching selection operation by the switching selection means is stopped. The antenna input of the best reception level selected by the antenna selection means may be selected as the antenna input for the tuning operation by the tuning control means. Further, the present invention is provided by a plurality of antennas.
Switching selection operation to sequentially switch and select each antenna input
And a plurality of switches sequentially selected by this switching selection operation.
The reception level of each antenna input given from the antenna
Ann to compare and select the antenna input with the best reception level
The diversity reception method that executes the tenor selection operation
Therefore, the start of the tuning operation during the switching selection operation is
Even if instructed, the antenna input of the best reception level selected by the antenna selecting operation, in which so as to-option selected by the antenna input for tuning operation.

[0011]

[Operation] With the above configuration, a plurality of antennas are
Antenna using the antenna with the highest reception level
Tuning operation can be performed and tuning accuracy
Can be improved .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a system configuration of a television receiver equipped with a diversity function according to an embodiment of the present invention, which is basically the same as that shown in FIG. Is attached and the description thereof is omitted.

However, the RF from the RF switch circuit 14
The television receiver main body 21 supplied with the signal a sends out the video signal b to the sample hold circuit 15, while the controller in the diversity unit 12 continues from the time when the channel selection is instructed to the time when the channel selection is completed. A tuning mode detection signal f is sent to 22. The controller 22
The selection signal e is output to the RF switch circuit 14 according to the comparison result d from the comparator 16 to control the switching selection operation of the receiving antenna 13, and the tuning mode detection signal f is input from the television receiver body 21. In the meantime, the switching selection operation is temporarily stopped.

Next, a detailed circuit configuration of the television receiver body 21 will be described with reference to FIG. The RF signal a from the RF switch circuit 14 in the diversity unit 12 is supplied to the tuner 31 in the television receiver body 11. The tuner 31 selects a designated channel from the RF signal a according to the tuning signal from the tuning control circuit 32, converts it into an intermediate frequency signal, and sends it to the TV linear circuit 33.

The TV linear circuit 33 is composed of an intermediate frequency amplification circuit, a video detection circuit, a video amplification circuit, an AFT detection circuit, etc., which amplifies the intermediate frequency signal from the tuner 31 and also produces an image by the video detection circuit. To detect. Then, an audio signal is taken out from the output signal of the video detection circuit and sent to the audio circuit 34.

The audio circuit 34 is composed of an audio detection circuit and an audio amplification circuit. The audio signal from the TV linear circuit 33 is audio-detected and converted into a low frequency signal, and then the audio signal is amplified and the speaker 35 is amplified. To drive.

Further, the output signal of the video detection circuit in the TV linear circuit 33 is amplified by the video amplification circuit, and then is output as the video signal b to the diversity unit 12.
While being output to the sample and hold circuit 15 therein, it is also sent to the chroma circuit 36 and the sync separation circuit 37.

The sync separation circuit 37 separates and extracts the horizontal and vertical sync signals contained in the video signal, outputs the composite sync signal C-SYNC to the tuning control circuit 32, and the horizontal sync signal H-SYNC and the vertical sync signal. V-SYNC is sent to the timing control circuit 38, respectively. In addition, the TV linear circuit 33 outputs the output signal of the intermediate frequency amplifier circuit to A
The FT detection circuit performs AFT detection to extract an AFT signal having an S-shaped characteristic curve, and the tuning control circuit 32
Send to.

The tuning control circuit 32 is provided with key inputs such as tuning setting data and tuning up / down instructions from the key input section 39. The tuning control circuit 22 uses the tuning up / down in the key input section 39. And a tuning signal is created based on the AFT signal from the TV linear circuit 33 and sent to the tuner 31, and tuning up / up is performed.
The tuning mode detection signal f is output to the controller 22 in the television receiver body 11 from the time the down instruction is given until the tuning operation is completed.

The timing control circuit 38 has a sampling signal φ based on the horizontal sync signal H-SYNC and the vertical sync signal V-SYNC sent from the sync separation circuit 37.
s is created and sent to the A / D conversion circuit 40.

The A / D conversion circuit 40 samples the chroma signal output from the chroma circuit 36 in synchronization with the sampling signal φs, converts the chroma signal into digital data of 3 to 4 bits, and sends the digital data to the segment drive circuit 41. To do. Also,
The timing control circuit 38 is provided with a horizontal synchronizing signal H-SYNC and a vertical synchronizing signal V-S supplied from the sync separating circuit 37.
A timing signal for display control is created based on YNC to control the operation of the segment drive circuit 41 and the common drive circuit 42.

The common drive circuit 42 generates a scanning signal in accordance with the timing signal from the timing control circuit 38, and sequentially selects and drives the common electrodes of the liquid crystal display panel 43. Further, the segment drive circuit 41 sequentially reads the 3-4 bit video data supplied from the A / D conversion circuit 40 in accordance with the timing signal from the timing control circuit 38, reads the video data for one line, and then reads the video data. A gradation signal is generated according to the above, and the segment electrodes of the liquid crystal display panel 43 are driven to display.

Next, the operation of the above embodiment will be described with reference to FIG. FIG. 3 mainly shows the video signal b in the vertical blanking period. When the video signal b is sent from the television receiver main body 21 to the sample hold circuit 15 in the diversity unit 12, the sample hold circuit 15 is shown in FIG.
The horizontal synchronizing signal is sampled at the timing indicated by α1 and is input and held as the currently selected reception level X.

Next, the sample and hold circuit 15 sequentially samples the horizontal synchronizing signals at the timings .alpha.2 to .alpha.4 in FIG. 3, and inputs and holds the reception level Y of the unselected receiving antenna. That is, at this time the controller
22 controls the RF switch circuit 14 by the selection signal e,
The receiving antennas of the receiving antennas different from the receiving antenna selected at the timing of α1 are sequentially switched and selected. Then, the reception level X of the sample and hold circuit 15,
Y is a comparator for receiving level signals c1 and c2
It is compared in 16 and the selection signal e is output to select the receiving antenna with the higher receiving level according to the comparison result d.

However, when a tuning up / down operation is performed by the key input section 39 of the television receiver body 21, the tuning control circuit 32 executes the tuning operation as described with reference to FIG. Until the operation is completed, the diversity unit 12
The tuning mode detection signal f is output to the controller 22 of FIG.

At the time of inputting the tuning mode detection signal f, the controller 22 temporarily suspends the selection switching operation of the receiving antenna 13 by the RF switch circuit 14 to switch and select the receiving antenna selected in the previous field.

This is because, especially when the tuning up / down operation is performed during the periods indicated by β, γ, and δ in FIG. 3, tuning is performed in the state where the receiving antenna other than the receiving antenna with the highest receiving level is selected. This is to prevent the operation from being executed, and by switching the receiving antenna selected in the previous field, the receiving antenna having the highest receiving level at least immediately before that is provisionally selected. It is a thing.

When the tuning operation in the television receiver body 21 is completed and the tuning mode detection signal f is no longer input, the controller 22 restarts the diversity operation.

In the above embodiment, the television receiver body 21
The diversity unit 12 and the diversity unit 12 are described as separate bodies, but it goes without saying that they may be integrated to form a television receiver having a built-in diversity unit.

[0030]

As described above, according to the present invention, a plurality of
Use the antenna with the highest reception level among other antennas
You can perform tuning operations by
Tuning accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration in the television receiver body of FIG.

FIG. 3 is a diagram for explaining the operation according to the embodiment.

FIG. 4 is a block diagram showing a system configuration of a television receiver equipped with a conventional diversity function.

[Explanation of Codes] 11, 21 ... Television receiver main body, 12 ... Diversity unit, 13 ... Receiving antenna, 14 ... RF switch circuit, 15 ... Sample hold circuit, 16 ... Comparator, 17, 22 ... Controller, 31 ... Tuner, 32 ... Tuning control circuit,
33 ... TV linear circuit, 34 ... Audio circuit, 35 ... Speaker, 36
... Chroma circuit, 37 ... Synchronous separation circuit, 38 ... Timing control circuit, 39 ... Key input section, 40 ... A / D conversion circuit, 41 ... Segment drive circuit, 42 ... Common drive circuit, 43 ... Liquid crystal display panel.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B ⁷ /02-7/12 H04L 1/02-1/06

Claims (5)

(57) [Claims] 1. An antenna provided by a plurality of antennas
Tuning selection means for sequentially switching and selecting the input, antenna selection means for comparing the reception levels of the respective antenna inputs sequentially switched and selected by the switching selection means, and selecting the antenna input of the best reception level; tuning; The tuning control means for executing the operation and the opening of the tuning operation by this tuning control means.
Instructing means for instructing start, and switching selection operation of each antenna input by the switching selection means
Instructing start of tuning operation by the instructing means
Even if it is, the antenna of the best reception level selected by the antenna selection means is used as the antenna input for the tuning operation by the tuning control means.
Diversity receiving apparatus characterized by comprising an antenna control unit to select the antenna input. 2. A detection means for detecting execution of a tuning operation by the tuning control means, wherein the switching selection means carries out the switching selection operation at predetermined intervals.
To perform, the antenna control means, each of A by the switching selecting means
When the execution of the tuning operation is detected by the detecting means during the switching selection operation of the antenna input, the current switching selection operation by the switching selection means is stopped and the antenna selection is performed in the previous switching selection operation by the switching selection means. the best antenna input of the receiver level selected by means, diversity receiving apparatus according to claim 1, wherein the selecting as an antenna input for tuning operation by the tuning control means. 3. The detection means includes means for detecting the end of the tuning operation by the tuning control means, and the antenna control means is operated by the switching selection means until the end of the tuning operation is detected by the detection means. The diversity receiving apparatus according to claim 2, wherein the switching selection operation is stopped. 4. Before SL tuning control means starts the tuning operation when the start of the tuning operation is instructed by said instructing means, said switching selection means every predetermined cycle said switching selection operation
To perform, the antenna control means, each of A by the switching selecting means
When the tuning means is instructed to start the tuning operation during the switching selection operation of the antenna input, the current switching selection operation by the switching selection means is stopped and the antenna selection is performed in the previous switching selection operation by the switching selection means. the best antenna input of the receiver level selected by means, diversity receiving apparatus according to claim 1, wherein the selecting as an antenna input for tuning operation by the tuning control means. 5. Each antenna provided by a plurality of antennas
Switching selection operation that sequentially selects and selects the input
From multiple antennas that are sequentially switched and selected by selecting operation
The reception level of each antenna input that can be obtained is compared and the best reception is obtained.
Antenna selection operation to select the antenna input of signal level
The diversity reception method for executing the step of performing a tuning operation is instructed to start during the switching selection operation.
Even when diversity reception method characterized in that said antenna selection operation by the antenna input of the selected best reception level and-option selected by the antenna input for tuning operation.