JP2757399B2 - Receiving machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a broadcast signal receiver multiplexed with additional data such as RDS, which is implemented in Europe.

[Summary of the Invention]

The present invention relates to a receiver, in which a second reception system is sequentially tuned using a list of broadcast signals in additional data, and the first reception system is made to follow a broadcast signal having the maximum reception level. In this case, a good broadcast signal is always received by the receiving system.

[Conventional technology]

For example, in RDS conducted in Europe, F
Additional data is multiplexed on M broadcast, and a list of broadcast signals broadcasting the same program is provided in the additional data.

For example, in an in-vehicle receiver, when the vehicle goes out of the service area of an arbitrary broadcast signal by driving, the broadcast signal is switched according to the above-mentioned list, and the same program is tracked and listened by selecting the best broadcast signal. Is what you can do.

[Problems to be solved by the invention]

By the way, the following can be automatically performed in the receiver.

That is, for example, the reception level of the broadcast signal is detected, and when this level falls below the permissible value, each broadcast signal is sequentially received according to the above-mentioned list, and the broadcast signal whose reception level exceeds the permissible value is selected. Alternatively, automatic follow-up is performed by receiving another broadcast signal according to the above list instantaneously in a time-sharing manner while receiving an arbitrary broadcast signal, and switching the whole reception to a broadcast signal having the maximum reception level.

However, in the former method, it takes a relatively long time from when the reception level becomes equal to or lower than the allowable value to when a broadcast signal having the reception level equal to or higher than the next allowable value is selected. Reception is interrupted. Also, the best reception was not always possible.

On the other hand, in the latter method, the best reception can always be performed. However, since other broadcast signals are detected in a time-division manner during reception, the output sound is dropped even though it is instantaneous. In addition, in order to perform detection in an extremely short time, a high-speed detection circuit is required, and, for example, a PLL synthesizer in the receiving unit also needs to perform frequency shift at an extremely high speed, and the configuration of these high-speed circuits is complicated. It was expensive as well.

The present application has been made in view of such points.

[Means for solving the problem]

The present invention provides a first receiving system for receiving a broadcast signal ((2)
To (9)) and means for detecting the additional data multiplexed on the received broadcast signal and storing a list of the broadcast signals broadcasting the same program in the data (system control circuit (7)). ), The decoder (14)) and the second receiving system ((1
5) to (21)), the second reception system is sequentially tuned to all the broadcast signals included in the list, and the reception level becomes maximum (peak hold circuit (22),
Comparator (23) A receiver characterized in that the first reception system follows the broadcast signal.

[Action]

According to this, by providing the second receiving system, it is possible to detect other broadcast signals without affecting the broadcast signal being received, and it is possible to always perform the best reception. The second receiving system does not need to be driven at a high speed, and the detection need only be able to detect the reception level.

〔Example〕

In FIG. 1, a signal from an antenna (1) is supplied to a band-pass filter (2), an RF amplifier (3), and a band-pass filter (4). 5).

On the other hand, a local oscillation signal from, for example, a PLL synthesizer oscillator (6) is supplied to the mixer (5). Here, this oscillator (6) is controlled by a system control circuit (microcomputer) (7) described later.
For example, a signal of 98.70 to 118.70 MHz is oscillated.

The signal from the mixer (5) is supplied to a band-pass filter (8), and an intermediate frequency signal of, for example, 10.7 MHz is extracted. The extracted signal is supplied to an FM demodulation circuit (10) through an IF amplifier (9), and the demodulated signal is separated left and right by a multiplexer (11), and output terminals are respectively passed through buffer amplifiers (12L) and (12R). (13L) (1
3R). As a result, a normal broadcast signal is received.

Further, during this reception, a part of the signal from the IF amplifier (9) is supplied to, for example, an RDS decoder (14), and a list of broadcast signals broadcasting the same program in the additional data is extracted. This list is supplied to the system control circuit (7).

A signal from the antenna (1) is supplied to a band-pass filter (15), an RF amplifier (16), and a band-pass filter (17). For example, a frequency component of 88.00 to 118.00 MHz is extracted and supplied to a mixer (18). Is done.

On the other hand, the mixer (18) is supplied with an oscillation signal from, for example, a PLL synthesizer oscillator (19). Here, the oscillator (19) is controlled by the system control circuit (7), and a signal of, for example, 109.70 to 129.70 MHz is oscillated.

The signal from the mixer (18) is supplied to a band-pass filter (20), and a signal component of, for example, 21.7 MHz is extracted. The extracted signal is supplied to the peak hold circuit (22) through the IF amplifier (21), and the peak hold value and the signal from the original IF amplifier (21) are supplied to the comparator (23). A determination signal when the signal level from (21) exceeds the peak hold value is supplied to the system control circuit (7).

Therefore, in this apparatus, received data of an arbitrary broadcast signal is output from the system control circuit (7) by the operation of the operation means (not shown), and this data is supplied to the oscillator (6) and the system control circuit ( The latch signal A from 7) is supplied to the oscillator (6), and the above data is latched. As a result, an arbitrary broadcast signal is received by the first receiving system such as the mixer (5) and the oscillator (6), and this audio signal is output to the output terminal (13L) (1
3R).

At the same time, the decoder (14) detects the RDS in the broadcast signal, extracts a list of broadcast signals broadcasting the same program in the data, and stores the list in the system control circuit (7).

In accordance with the list of broadcast signals stored in the system control circuit (7), data for receiving the broadcast signals is sequentially output, and this data is supplied to the oscillator (19) and the system control circuit (7) ) Is supplied to the oscillator (19), and the above data is latched. Thus, the broadcast signals in the above list are sequentially received by the second receiving system such as the mixer (18) and the oscillator (19), and the received signals are supplied to the peak hold circuit (22) and the comparator (23). .

For this reason, the comparator (23) outputs a discrimination signal every time the reception level exceeds the value of the previously held peak, and the system control circuit (7) stores the data of the broadcast signal at that time in the register. . The hold value from the peak hold circuit (22) is slightly delayed. Then, when the above list is cycled, the peak hold circuit (22) is reset, and at this time, the data of the broadcast signal having the highest reception level in the list is held in the register by the system control circuit (7). By supplying this data to the oscillator (6), the best reception can always be performed.

When the detected broadcast signal is the same as the one being received, it is not necessary to resupply the same data to the oscillator (6).

Also, during reception during traveling, the reception level may temporarily fluctuate due to multipath or fading. Therefore, the above-described detection may be repeated about three times in the list, and the same data may be supplied to the oscillator (6) when the same data is prepared.

Thus, according to the above-described device, by providing the second receiving system, it is possible to perform another broadcast signal without affecting the broadcast signal being received, and to always perform the best reception, The second receiving system does not need to be driven at a high speed and can be configured at a very low cost because the detection only needs to detect the reception level.

The above-described apparatus is applied to a case where a broadcast signal list of the same program is provided in the additional data of the broadcast signal.

〔The invention's effect〕

According to the present invention, by providing the second receiving system, it is possible to detect another broadcast signal without affecting the broadcast signal being received, and to always perform the best reception, The second receiving system does not need to be driven at a high speed, and the detection need only be able to detect the reception level. Therefore, the second receiving system can be configured at very low cost.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an example of the present invention. (1) is an antenna, (2) (4) (8) (15) (17)
(20) is a bandpass filter, (3) (9) (12L) (1
2R) (16) and (21) are amplifiers, (5) and (18) are mixers,
(6) (19) is a PLL synthesizer oscillator, (7) is a system control circuit, (10) is a demodulation circuit, (11) is a multiplexer, (13L) and (13R) are output terminals, (14) is a decoder, and (22) ) Is a peak hold circuit, and (23) is a comparator.

Claims (1)

(57) [Claims] 1. A first receiving system for receiving a broadcast signal, and a list of the broadcast signals broadcasting the same program in the data by detecting additional data multiplexed on the received broadcast signal. And a second receiving system having a different intermediate frequency from the first receiving system. The second receiving system is sequentially tuned to all the broadcast signals included in the list. A receiver characterized in that the first reception system follows the broadcast signal having the maximum reception level.