JPS62198212A - Radio receiver having same program identification function - Google Patents

Abstract

PURPOSE:To ensure the identification of the identity of programs by decomposing demodulation output of a couple of tuners into frequency components and identifying the identity of the program based on >=2 waves of frequency components. CONSTITUTION:As to the identification of the identity of a broadcast program, two signal processing circuits 8, 9 detects the modulation component dividedly, the result is coded into '0', '1' binary signals, coincidence detection circuits 84, 94 apply equivalent operation at each band and the outputs are subject to AND operation by a gate circuit 10. When number of pulses outputted from the gate circuit 10 is consecutive by a prescribed number, the same decision signal is given from a decision circuit 12 to a system controller 13. The demodulation output of the tuner is decomposed into frequency components and the identity of the program is decided based on the 2-wave of frequency components in this way, then the more accurate program identification is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION [1] The present invention relates to a radio receiver having a same program identification function.

Equipped with a pair of tuners capable of anti-type automatic channel selection operation, when one tuner is in the receiving state, the other tuner searches for another station that is simultaneously broadcasting the same program as the broadcast program it is currently receiving. Then, when the reception condition of one tuner deteriorates, the station automatically switches to the reception station of the other tuner that is broadcasting the ID program, thereby selecting a station with better reception condition. There is a radio receiver. According to this radio receiver, for example, self! Even if the reception condition deteriorates due to a change in the service area of a broadcasting station while the vJrJ1 is driving, the station will automatically switch to a station with better reception, so the driver will have to tune in. Therefore, such a radio receiver is suitable for use in a car.

Such a radio receiver must include an identification circuit that identifies, based on the demodulated outputs of the pair of tuners, that the broadcast programs of the receiving stations of both tuners are the same. Conventionally, this identification circuit has a configuration that detects the frequency component of each tuner output and identifies the identity of the program based on the rain detection component. Since the identification is carried out using the same method, the reliability of the identification operation is lacking.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a radio receiver having a same program identification function that can more reliably identify the sameness of broadcast programs.

The radio receiver having the same program identification function according to the present invention detects the frequency components of each demodulated output of a pair of tuners using at least two types of filter circuits with different frequency bands, and converts the frequency components into binary signals. The theory of detecting the -/match of the logic of a pair of binary signals and outputting the -number structure of each]! I! The system is configured to identify the identity of broadcast programs based on the number of pulses of the product output.

Friend-presenting-1 Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

In the figure, an RF (high frequency) received signal from an antenna 1 is sent to a pair of tuners (1, II) 3.4 via a distributor 2.
is supplied to A pair of tuners 3.4 are mounted on a font 30.40. IF (intermediate frequency) amplifier 31.41.
It consists of wave detectors 32, 42, a PLL controller 33.43, and a received field strength level detection circuit 34.44, and has a well-known PLL synthesizer type electronic tuner configuration capable of automatic tuning operation. The demodulated outputs of these tuners 3.4 are supplied to a switching circuit 5, which selects one of them, amplifies it with a low frequency amplifier 6, and supplies it to a speaker 7.

The demodulated outputs of the pair of tuners 3 and 4 are also supplied, for example, to two signal processing circuits 8.9. One of the signal processing circuits 8 includes a pair of BPFs (band pass filters) 80.81 in predetermined frequency bands that detect the frequency components of each demodulated output of the pair of tuners 3 and 4, and encodes each output of these BPFs 80.81. A pair of zero cross detectors 82, 83 as a waveform processing circuit that converts the signal into a binary signal of O"11111, and these zero cross detectors 82.8
3, and a coincidence detection circuit 84 that outputs a detection pulse in which the logics of the three output pulses match. Similarly, the other signal processing circuit 9 includes a pair of BPFs 90.91, a pair of zero cross detectors 92゜93, and a -number output circuit 94/It l-J, and the signal processing circuits 8 and the like include a pair of [3P F 9 ( 1') One frequency band is a pair of B
It is configured differently from that of PF80.81.

- An exclusive NOR circuit with a well-known configuration can be used as the number output circuits 84 and 94.

Each detection pulse outputted from the two signal processing circuits 8 and 9 is supplied to a gate circuit 10 to perform an AND operation. A counter 11 which receives the output pulses of the circuit 10 as a count input generates a determination pulse when the number of input pulses reaches a predetermined value, and supplies the determination pulse to the determination circuit 12.

The determination circuit 12 generates an identical determination signal in response to this determination pulse and supplies it to the system controller 13.

The system controller 1-0-13 is a CP that forms the center of operation.
Consists of U (central processing unit) 130, external memory 131, clock pulse generator 132 and frequency dividing circuit 133,
Control of each PLL controller 33.43 in Cυ of a pair of tuners 3, 4, switching control of switching circuit 5, detection output of received field strength level detection circuit 34.44, and same judgment signal from judgment circuit 12. Storage of station number of broadcast program layer in memory 131, clock pulse control circuit 14
performs operations such as sending out clock pulses for the

The clock pulse control circuit 14 sets the number of numbering pulses and the number of match determination reference pulses when controlling the gate circuit 10, counter 11, and determination circuit 12.

Next, the operation of this configuration will be explained.

Assuming that the demodulated output of the tuner (II) 3 is now selected by the switching circuit 5, the tuner (II) 4 is in the search mode, and the system controller 1 roller 13 is always connected to the received electric field strength level detection circuit 34. Detection of the received field strength level of each receiving station based on the output of the determination circuit 12 and program identification determination of whether the broadcast programs of both tuners are the same or not based on the determination output of the determination circuit 12 are performed, and the determination circuit 12 issues an identical determination signal. When the station number is output, the station number of that station is stored in the memory 131, and weighting is performed according to the received field strength level.

For identification and identification of broadcast programs, two signal processing circuits 8
．． 9'(-='3: The harmonic components are divided and detected, and II
The signal is encoded into a binary signal of OII II 1°', and the coincidence detection circuits 84 and 94 perform equality operations for each band, and the gate circuit 10 performs an AND operation on the outputs. Next, goo 1
~When the number of pulses output from the circuit 10 is a predetermined number in succession, the determination circuit 12 issues the same determination signal to the system controller 13. In this way, the demodulated output of the tuner is decomposed into frequency components and
By determining the identity of programs based on the frequency components of the waves, program identification can be performed more accurately.

When the receiving condition of the tube (2) during reception deteriorates, the system controller 13 detects the signal based on the output of the received field strength level detection circuit 34, and drives the switching circuit 5 to switch to the demodulated output of the tuner (2). At this time, the system controller 13 reads out the station number with the highest level among the station numbers that have been determined to be the same program and is weighted according to the received field strength level and stored in the memory 131, and uses the PLL controller to avoid receiving the station with that station number. 1 to roller 43 are controlled. This allows stations broadcasting the same program to be received in the best reception condition. At this time, the tuner (2), which was previously receiving data, enters the search mode, and similarly to the case of the tuner (2), the reception field strength level of each receiving station is detected and the program identification is determined.

FIG. 2 is a time chart showing the switching operation of the tuner Lff when the same program is being broadcast on stations A, B, and 0, and it can be seen that the tuner output with the better reception condition is always selected. Recognize.

J3. In the above embodiment, a case was explained in which two pairs of BPFs were provided to detect the frequency components of the demodulated output of the tuner, but the present invention is not limited to this, and it is possible to provide three or more. , This makes it possible to further improve the accuracy of identifying the identity of programs.

This has been explained above. 1. According to the present invention, the demodulated outputs of a pair of tuners are decomposed into frequency components, and the identity of programs is identified based on two or more frequency components. This can be done more reliably.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a time chart showing the switching operation of tuners I and II in FIG. Explanation of symbols of main parts 1...Antenna 3.4...Tuner 5.
...Switching circuit 8.9... Signal processing circuit 10 ... Gate circuit 12 ... Judgment circuit

Claims (1)

[Claims] A pair of tuners capable of automatic channel selection operation, and an identification circuit that identifies that broadcast programs received by both tuners are the same based on demodulated outputs of the pair of tuners,
A radio receiver configured to select the tuner output of the pair of tuners having a better reception condition when the identification circuit identifies that the same broadcast program exists in each receiving station of the pair of tuners. It is a machine,
The identification circuit includes a pair of filter circuits in a predetermined frequency band that detects frequency components of demodulated outputs of the pair of tuners, and encodes each output of the pair of filter circuits.
It consists of a pair of waveform processing circuits that convert into a value signal, and a coincidence detection circuit that outputs a detection pulse when the logic of each output of the pair of waveform processing circuits matches, and the filter circuits have at least two different frequency bands. Same program identification, comprising two signal processing circuits, and identifying the sameness of broadcast programs based on the number of pulses of the AND output of each detection pulse of the at least two signal processing circuits. Radio receiver with functions.