JPH0227816A - On-vehicle type tv receiver - Google Patents

Abstract

PURPOSE:To select a system in the best reception state properly by providing at least 2 TV signal reception systems and their control sections. CONSTITUTION:The 1st TV signal reception system consists of the 1st reception antenna 11A, the 1st tuner circuit 12A, the 1st video IF circuit 13A and the 1st detection circuit 14A and the 2nd TV signal reception system consists of the 2nd reception antenna 11B, the 2nd tuner circuit 12B, the 2nd video IF circuit 13B and the 2nd detection circuit 14B. Then a CPU 15 fetches a required signal component from the 1st and 2nd video IF circuits 13A, 13B and the 1st and 2nd detection circuits 14A, 14B, switches a switch circuit 16 to select a signal reception system with better reception state. Thus, the proper reception state is realized without increasing much manufacture cost.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a vehicle-mounted TV receiver,
In particular, the present invention relates to a vehicle-mounted TV receiver that is equipped with at least two TV signal receiving systems and their control units, and is capable of accurately selecting the system with the best reception condition.

[Prior Art 1] FIG. 2 is a schematic configuration diagram showing a conventional vehicle-mounted TV receiver. In this Fig. 2, the receiving antenna (21)
, a tuner circuit (22), a video IP circuit (23) and a detection circuit (24). At the latter stage of this TV signal receiving system, there is a video signal output section consisting of a color processing circuit (25), an H/V circuit (26), and a CRT (2)), a sound IF circuit (28), and a speaker (29). ) is connected to the sound signal output section.

Next, the operation of the above conventional example will be explained. Now, when this vehicle-mounted TV receiver is turned on and tuned to a desired channel, the desired video signal and sound signal are transmitted to the final stage CRT (2 )) and speaker (29)
will be output from. By the way, a vehicle equipped with such a vehicle-mounted TV receiver may enter a place with poor reception conditions for TV signals, such as on a road in a high-rise building area, or if the vehicle is equipped with such a vehicle-mounted TV receiver. When you go out of the service area, the reception conditions for the TV signal you are receiving may deteriorate or fluctuate, making it impossible to receive the TV signal due to the fluctuations in the electric field, and nothing may appear on the CRT (27).

[Problems to be Solved by the Invention] The conventional vehicle-mounted TV receiver described above is
Since only a signal reception system is provided, it is not possible to respond accurately even if the reception condition of the TV receiver deteriorates as the vehicle moves, and in the worst case, reception becomes impossible. There was a problem.

This invention was made to solve the above-mentioned problems, and includes at least two TV signal receiving systems and a control section for them, and accurately selects the system with the best reception state. The purpose of the present invention is to obtain a vehicle-mounted TV receiver that can be selected.

[Means for Solving the Problems] A vehicle-mounted TV receiver according to the present invention has at least two
The system includes a TV signal receiving system and a control section thereof.

[Operation] According to the present invention, it is possible to select the system with the best reception condition from at least two TV signal reception systems.

[Example] Next, the present invention will be described based on an example shown in the accompanying drawings.

FIG. 1 is a schematic configuration diagram showing a vehicle-mounted TV receiver that is an embodiment of the present invention. In this FIG. 1, the first TV signal receiving system includes a first receiving antenna (11^)
, the first tuner circuit (12^), the first video IF circuit (
13^) and a first detection circuit (14A), and the second TV signal receiving system includes a second receiving antenna (II
B), a second tuner circuit (12B), a second video IF circuit (13B), and a second detection circuit (14B). connects the color processing circuit (25), H/V circuit (26) and C
A video signal output section consisting of an RT (27) and a sound signal output section consisting of a sound IF circuit (28) and a speaker (29) are connected.

In addition, the separately provided CPU (15) connects the first and second video IP circuits (13^), (13B), and the first
, the second detection circuit (14^), <14B), and the switch circuit (16).

Next, its operation will be explained. First, when the vehicle-mounted TV receiver is turned on and tuned to a desired channel, the desired video signal and sound signal are transmitted to the final stage CRT (27 ) and the speaker (29). Now, the first receiving antenna (11^
) is selected and received from the first TV signal receiving system starting from CRT (27) and speaker (
29). At this time, the first video IF circuit (13^) and the first detection circuit (14)
The required signal components from ^) are taken into the CPU (15) and the corresponding envelope signal A is obtained. On the other hand, a scanning operation for receivable TV signals in a second TV signal receiving system starting from the second receiving antenna (11B) is being performed in parallel, and a scanning operation for receivable TV signals in the first TV signal receiving system is being performed in parallel. Search for envelope signal B having the same waveform as the received signal. When the envelope waveforms of both are the same, the one with the better reception condition will be selected. That is, if the reception condition in the first TV signal reception system is better, the switch circuit (16
) is not switched, and on the other hand, if it is determined that the reception condition in the second TV signal reception system is better, the switch circuit (16) is switched and the second TV signal reception system is switched. A signal receiving system will be selected. In this way, it is possible to accurately select and receive the TV signal with the best reception condition among the TV signals of the same content received while the vehicle is moving.

[Effects of the Invention] As explained above, the vehicle-mounted TV according to the present invention
The receiver is equipped with at least two TV signal reception systems and their control units, and the control unit is capable of selecting the system with the best reception condition. The effect is that a vehicle-mounted TV receiver that can realize a suitable reception state can be obtained without significantly increasing the manufacturing cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a vehicle-mounted TV receiver according to an embodiment of the present invention, and FIG. 2 is a schematic diagram of a conventional vehicle-mounted TV receiver. (11^), (IIB) are the first and second receiving antennas, (
12^), (12B) are the first and second tuner circuits, (1
3^), (13B) are the first and second video IF circuits, (1
4A) and (14B) are the first and second detection circuits, (15) is the CPU, (16) is the switch circuit, (25) is the color processing circuit, (26) is the H/V circuit, (2)) is the CRT, (28) is a sound IP circuit, and (29) is a speaker.

Claims (1)

[Claims] (1) A vehicle-mounted TV receiver comprising at least two TV signal receiving systems and their control units, the control unit being able to select the system with the best reception condition. Machine.