JPH0438020A - On-vehicle diversity receiver - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vehicle-mounted diversity receiving device that automatically switches between a plurality of antennas installed in a vehicle depending on reception conditions.

2. Description of the Related Art A conventional vehicle-mounted diversity receiver is described in, for example, Japanese Utility Model Publication No. 58-21247. This diversity receiving device detects that the input signal level from the currently selected antenna has decreased, or that a steep electric field fluctuation has occurred due to multipath distortion,
It automatically switched to another antenna.

In some cases, one of the antennas may be defective, or
Or, if the cable connecting the antenna and receiver is disconnected or there is a connection error, the defective antenna will not be selected and will automatically switch to another normal antenna. It was not possible to confirm that there was an antenna (the antenna itself was defective, the cable was disconnected, or the antenna was connected incorrectly).

For example, when installing a receiver on a car manufacturing line or at a car dealership, you can check whether multiple antennas are working properly or not by operating the receiver and hearing radio broadcasts normally. Unable to confirm. In other words, the antenna is automatically switched to the antenna with the best reception among multiple antennas at the receiver installation location, so even if the antenna that was not selected at the receiver installation location is defective, the antenna No defects could be confirmed.

The present invention solves the above-mentioned conventional problems, and provides an in-vehicle diversity receiver that can forcibly switch antennas and easily confirm whether the antenna is normal or defective at the location where the receiver is installed. .

Means for Solving the Problems In order to achieve the above object, the present invention includes a plurality of antennas installed in a vehicle, a signal selection means for selecting one of the signals received by the plurality of antennas, and a signal selection means for selecting one of the signals received by the plurality of antennas, and demodulation means for demodulating the signal selected by the selection means; signal switching control means for outputting a switching signal to the signal selection means according to the signal reception state of each of the antennas; Received signal forced switching means for outputting a switching signal for forcibly selecting one of the received signals received by the antenna to the signal selection means; The present invention is characterized by comprising means for lighting up the display means when the display means is turned on.

Operation The present invention has the above-mentioned configuration, and when a specific operation such as pressing two preset channel selection buttons at the same time, one of the received signals received by a plurality of antennas is forcibly selected. Since the switching signal to select the signal is output to the signal selection means, one of the received signals received by the plurality of antennas is forcibly selected, and the reception level of the signal received by the selected antenna is above a certain value. If there is, the display will light up. Therefore, the operator can confirm whether the antenna is normal by visually observing whether the indicator is lit or not.

Embodiment FIG. 1 shows an embodiment of the present invention. This embodiment is an in-vehicle audio device in which a cassette deck and a radio receiver are integrated. In FIG. 1, LA and IB are antennas installed in a car, 2 is an antenna switching circuit for selecting antenna IA or IB, and 3 is a PLL synthesizer receiving circuit (hereinafter referred to as receiving circuit).
It consists of a tuner, demodulation circuit, power amplifier, etc. 4A and 4B are speakers, and 5 is a reception control circuit for controlling the reception circuit 3, and this reception control circuit 5 is composed of a microcomputer and the like.

6 is an operation panel provided with operation buttons, a display, etc., and 7 is an antenna switching control circuit that outputs an antenna switching signal according to the IF signal level output from the receiving circuit 3 and/or the multipath detection result.

8 is a cassette deck, and this cassette deck 8 is
It is controlled based on signals from the operation panel 6. The reproduction output of the cassette deck 8 is supplied to a power amplifier within the receiving circuit 3.

In FIG. 1, when the antenna switching circuit 2 is currently switched to the antenna itself, and the reception condition of the antenna IA deteriorates, the antenna switching control circuit 7 outputs an antenna switching signal to the antenna switching circuit 2, and the antenna switches. I
Automatically switches from A to IBm.

FIG. 2 shows the operation panel 6 of the above embodiment. ′
In the W%2 diagram, a to f are operation buttons that serve as preset channel selection buttons and deck control buttons, g is an operation button that combines a power switch and volume adjustment volume, and h is a display. The display unit has a display section i that displays the reception frequency.
and a running direction display section j for displaying the running direction of the magnetic tape during operation of the cassette deck. The running direction display section j lights up when the magnetic tape is running in the first direction, and the running direction display section j lights up when the magnetic tape is running in the second direction opposite to the first running direction. It lights up when the machine is running. m is a cassette insertion hole.

Next, the antenna confirmation mode of this embodiment will be explained with reference to FIG. Turn on the power switch by operating operation button g on the operation panel 6 shown in FIG. Pressing them at the same time will switch to antenna confirmation mode. As shown in FIG. 3, when it is determined that the two preset operation buttons a and f have been pressed in step 1, an antenna confirmation mode command is output from the reception control circuit 5 to the antenna switching control circuit 7, and the antenna switching The first antenna switching signal is output from the control circuit 7 for a certain period of time (step 2). Therefore, the antenna switching circuit 2 selects the antenna IAI for a certain period of time. Therefore, speaker 4A
, 4B output broadcast audio received by antenna IA for a certain period of time. Next, in step 3, it is determined whether the reception level of the signal received by the antenna IA is above a certain value. If it is determined in step 3 that the reception level is equal to or higher than a certain value, then in step 4 the traveling direction display section k is turned on. When step 4 is completed or it is determined in step 3 that the reception level is not higher than a certain value, step 5
Then, the antenna switching control circuit 7 outputs the second antenna switching signal to the antenna switching circuit 2 for a certain period of time. Therefore, the antenna switching circuit 2 switches from antenna IA to antenna IB. Therefore, the broadcast audio received by antenna IB is output from speakers 4A and 4B for a certain period of time. Next, the process proceeds to step 6, where it is determined whether the reception level of the signal received by antenna IB is equal to or higher than a certain value.

If it is determined in step 6 that the reception level is above a certain value, then in step 7 the driving direction display section j is turned on. When step 7 is completed, or when it is determined in step 6 that the reception level is not above a certain value, the process returns to the main routine in step 8. In this way, Prina IA and IB are forcibly switched, and when the reception level exceeds a certain value, the running direction display sections j and k for displaying the name and the running direction of the magnetic tape are lit. For this reason, the traveling direction display section j,
By visually observing the lighting, it is possible to confirm whether the antennas IA and IB are normal or defective (defective antenna itself, cable breakage, connection error, etc.).

FIG. 4 shows the operation of the second embodiment of the invention. In this embodiment, as shown in FIG. 4, it is determined whether preset tuning buttons a and C are pressed at the same time in step 1, and whether preset tuning buttons d and f are pressed at the same time in step 2. is determined. When it is determined in step 1 that preset tuning buttons a and C are pressed at the same time, the reception control circuit 5
A key determination result signal is output from the antenna switching control circuit 7 to the antenna switching control circuit 2.
An antenna switching signal is output to antenna IAIII.
I is forcibly selected (step 3).

In step 4, it is determined whether the reception level of the signal received by the antenna IA is above a certain value, and if the reception level is above the certain value, in step 5, the driving direction display section k
lights up. In step 6, it is determined whether or not preset tuning buttons a and C are continuously pressed, and if it is determined in step 6 that preset tuning buttons a and C are being pressed continuously, , the forced selection of antenna IA continues, but when the preset channel selection buttons a and C are no longer pressed, the normal diversity reception state returns (step 7). On the other hand, if it is determined in step 2 that the preset tuning buttons d and f are pressed simultaneously, an antenna switching signal is output from the antenna switching control circuit 7 to the antenna switching circuit 2 in step 8, and the antenna is switched to antenna IB. It will be done.

Next, in step 9, it is determined whether the reception level of the signal received by antenna IB is above a certain value, and if the reception level is above a certain value, the running direction display section j is turned on in step 10. In step 11, it is determined whether or not the preset channel selection buttons d and f are being pressed at the same time. If it is determined that they are being pressed, step 8
9.10 continues to be executed, and the preset channel selection buttons d and f are not pressed (if not, the process returns to the main routine in step 12 and returns to the normal diversity reception state. In this way, as shown in FIG. According to the embodiment shown, when preset selection buttons a and 01 or preset selection buttons d and f are pressed at the same time, one antenna is tilted while the preset selection buttons are pressed up. If it is forcibly switched and the reception level is above a certain value, the driving direction display section j or k will light up.Therefore, the operator can visually check whether the driving direction display section is lit or not. You can check whether the antenna LA (till) or antenna IB side is normal or defective.

FIG. 5 shows another embodiment of the invention. The embodiment shown in FIG. 1 is an example of a one-channel diversity receiver, whereas the embodiment shown in FIG. 5 is an example of a two-channel diversity receiver. In Figure 5, LA
, IB are antennas, and 9A and 9B are tuners. These tuners 9A and 9B are composed of a front end section consisting of a high frequency amplification circuit, a local oscillation circuit, and a mixer, and an IF section consisting of an intermediate frequency amplification circuit and a detection circuit. There is. 11 is a signal selection circuit for selecting one of the outputs of the tuners 9A and 9B; 10 is a reception circuit consisting of a stereo multiplex circuit, an amplifier, etc.; 5 is a reception control circuit; and 6 is provided with various operation buttons, indicators, etc. 12 is a tuner 9A.

A signal switching control circuit supplies a switching signal to the signal selection circuit 11 based on the IF signal level and/or multipath detection result from 9B, and 8 is a cassette deck.

In the two-channel diversity receiver shown in FIG. 5 as well, by operating a predetermined operation button on the operation panel, similar to the operation of the embodiment shown in FIG. 3 or 4,
By forcibly selecting one of the outputs of the tuner 9A or 9B and visually observing whether the traveling direction display sections j and k light up, it is possible to confirm whether the antennas IAf1M and IBflll are normal.

In the above embodiment, the running direction display unit that displays the running direction of the magnetic tape is turned on when the reception level is above a certain value, but the indicator that lights up when the reception level is above a certain value may be provided separately.

Further, it is not necessary to provide a plurality of display devices, and only one display device may be provided.

Effects of the Invention The present invention has the above configuration, and according to the present invention, the antenna is forcibly switched in response to a predetermined operation, the reception level is determined, and the indicator is turned on when the reception level is above a certain value. This has the advantage that it is possible to easily check whether each antenna is normal or not by visually observing the lighting of this indicator.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an in-vehicle diversity receiver according to an embodiment of the present invention, FIG. 2 is a front view of the operation panel of the device, FIG. 3 is an explanatory diagram of the operation of the device, and FIG. FIG. 5 is a block diagram of another embodiment. LA, IB... antenna, 2... e antenna switching circuit, 3... receiving circuit, 4A, 4B... deck, 9A
, 9B... tuner, lO... receiving circuit, 11.
- Signal selection circuit, 12... Signal switching control circuit. Name of agent: Patent attorney Shigetaka Awano (1 person)

Claims (3)

[Claims] (1) a plurality of antennas installed in a vehicle, a signal selection means for selecting one of the signals received by the plurality of antennas, and a demodulation means for demodulating the signal selected by the signal selection means; signal switching control means for outputting a switching signal to the signal selection means according to the signal reception state of each of the antennas; The present invention further includes a reception signal forced switching means for outputting a switching signal to be selected to the signal selection means, and a means for lighting the display means when the reception level of the signal received by the selected antenna is equal to or higher than a certain value. Characteristics of the in-vehicle diversity receiver. (2) A claim comprising received signal forced switching means that outputs a switching signal for forcibly selecting one of the received signals received by a plurality of antennas when a plurality of preset channel selection buttons are operated simultaneously. The vehicle-mounted diversity receiving device according to item 1. (3) The in-vehicle diversity receiving device according to claim 1, wherein a running direction indicator for displaying the running direction of the magnetic tape is used as the display means.