JP2770973B2 - Radio receiver auto-preset device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an auto-preset device for assigning and storing an appropriate reception frequency to each preset switch of a radio receiver having a predetermined number of preset switches.

In order to simplify tuning scanning, several preset switches are provided in an in-vehicle radio receiver or the like, and each of them is assigned a receiving frequency of each broadcasting station, and selects one of these switches. By pressing this button, the receiving broadcast station can be selected. The frequency assigned to each switch can be set individually or automatically for all switches simultaneously. The present invention refers to an auto-preset device for automatically setting all of the latter switches.

[Conventional technology]

In a typical representative auto-preset device of the related art, the setting of each preset switch is performed as follows.

First, when the auto preset is started, the search is started from the lowest frequency (eg, FM: 76.0MHz in Japan). When a broadcast station is found, the station is set to channel 1 and at the same time the signal level of the broadcast station is set. Continue to search, and if there is a broadcasting station, set it to the next channel,
Set the signal level. This operation is performed at the maximum frequency (for example,
Repeat until FM: 90.0MHz in Japan). If you set up to the maximum preset channel and there are more broadcast stations,
Compare the signal level of the preset station with the lowest signal level.If the signal level of the preset station is lower, remove that station and replace it with a new station. Is set. At this time, a process of rearranging the channels from channel 1 to the maximum preset channel in ascending frequency order is performed.

[Problems to be solved by the invention]

In some areas, multiple stations broadcasting the same content may be able to receive at a high signal level, and in that case, according to the conventional auto preset, a plurality of stations having the same broadcast content will be set. There is a problem that the number of stations having different broadcast contents that can be set is reduced, and the range of selection of broadcast contents is narrowed.

Therefore, an object of the present invention is to provide an auto-preset device in which a plurality of stations having the same broadcast content are not set even in such a case.

[Means for solving the problem]

FIG. 1 is a diagram showing a principle configuration of an auto preset device for a radio receiver according to the present invention.

In this figure, the radio receiver auto-preset apparatus of the present invention scans the reception frequency of the radio receiver 10 over the entire reception frequency range, detects a receivable broadcast station, and determines the reception frequency and reception level. Station detection means 20
And a frequency storage means 22 for storing each reception frequency and reception level determined by the reception station detection means in association with each preset switch. A frequency table 50 in which the frequencies of the stations are classified into the same group; and whether or not the broadcasting stations belonging to the same group as the receiving broadcasting stations detected by the receiving station detecting means 20 in the frequency table 50 are already stored. Determining means 53, when it is determined that the broadcasting station belonging to the same group as the receiving broadcasting station is already stored,
The broadcasting station having the lower reception level among the two broadcasting stations is provided with an auto-preset means 52 that does not store the information.

(Operation)

The judging means 53 judges whether a broadcasting station in the same group as the receiving broadcasting station has already been selected based on the frequency table 50.

When it is determined that a broadcasting station belonging to the same group as the receiving broadcasting station has not yet been selected based on the result of the determination by the determining means 53, the auto presetting means 52 sets the frequency corresponding to the receiving broadcasting station to the frequency. When it is stored in the storage means 22 and it is determined that a broadcasting station belonging to the same group as the receiving broadcasting station has already been selected, from among the receiving broadcasting station and broadcasting stations of the same group already selected, The frequency corresponding to one broadcast station is stored in the frequency storage unit 22.

Therefore, a plurality of broadcasting stations belonging to the same group are not stored in the frequency storage unit 22.

〔Example〕

FIG. 2 is a block diagram showing an example in which the present invention is applied to a superheterodyne type electronic tuned radio.

The radio wave received by the antenna 110 is amplified by the high-frequency amplifier 101, mixed with the local oscillation signal from the PLL synthesizer 107 in the mixer 102, passed through the bandpass filter 103, and becomes an intermediate frequency signal. This is amplified by the intermediate frequency amplifier 104, AM or FM detected by the detector 105, and the low frequency amplifier 106
And is supplied to the speaker 111. The PLL synthesizer 107 supplies a local oscillation signal having a frequency corresponding to an integer value supplied from the microcomputer 500 to the mixer 102, and a control voltage supplied to a voltage-controlled oscillator (VCO) inside the mixer 102 to the high-frequency amplifier 101. Is controlled so that the difference between the frequency of the received signal and the frequency of the local oscillation signal tuned to the tuning circuit is always constant. The output of the intermediate frequency amplifier 104 is also supplied to a microcomputer 500 via an analog-to-digital (A / D) converter 504. Microcomputer 5
Reference numeral 00 includes a CPU, a ROM, a RAM, and an input / output interface, and is also connected to the keyboard 502 so that information can be input. The keyboard 502 has preset keys "CH1", "CH2", "CH3", "CH4", and "CH5" keys for calling preset channels and presetting for each channel, and "AST" for auto preset. In addition to the keys, an "ASU" key for scanning to a higher frequency, an "ASD" key for scanning to a lower frequency, and the like are provided. When these keys are pressed, information corresponding to the pressed keys is taken into the CPU via the input / output interface in the microcomputer 500.

The ROM in the microcomputer 500 stores coded information in a format as shown in FIG. 3 corresponding to the frequency table 50 described above. This is FM
This shows an example of a broadcast, in which frequencies expressed in MHz for each area No. are grouped and stored. Since the frequency of the station where the same content is broadcast differs for each area (area), if the information is stored for a plurality of areas as shown in FIG. 3, the movement is frequently performed particularly like a radio for a vehicle. It is effective for what is expected.

A part of the RAM in the microcomputer 500 is also used as a memory for realizing the frequency storage means 22 (FIG. 1).

FIG. 4 shows a flowchart of software of the microcomputer 500 for realizing the receiving station detecting means 20 and the auto presetting means 52 in combination with the function of each unit described above. It should be noted that the software of the microcomputer 500 includes software for realizing other functions as an electronic tuned radio, but only the portion according to the present invention is shown in the figure. These are all properly coded microcomputers 50
0 is stored in the ROM. In FIG. 4, it is determined whether or not the "AST" key has been pressed (step a), and if it has been pressed, the following series of processing is executed. First, a frequency division ratio corresponding to the lowest reception frequency is given to the PLL synthesizer 107 (step b). In this state, the reception level is checked via the A / D converter 504 to check whether or not a broadcast has been received. (Step c). If there is no reception, the operation of stepping up the reception frequency (step o) by changing the frequency division ratio until the highest frequency is reached (step n) is repeated. If there is a reception, the reception level is stored, and it is determined whether or not a frequency in the same area as the frequency is already registered based on the frequency table of FIG. 3 (steps d and e). For example, the frequency and the reception level are compared with each other (steps f and g). If the reception level is lower than this, no operation is performed. To join the process. If it is determined in step e that registration has not been completed, it is then determined whether five broadcasting stations have already been registered (step i), and if there is still room, the frequency and its reception level are registered (step j). , Joins the processing of step n. If the five stations have already been registered in step i, the reception level is compared with that of the lowest registered reception level (steps k and l). If so, the frequency and its reception level are registered instead (step m), and the process joins the process of step n. Finally, when the highest frequency is reached in step n, the received frequencies are rearranged in ascending order (step p), and the process is terminated.

〔The invention's effect〕

As described above, according to the present invention, a plurality of broadcast stations having the same broadcast content are not preset, and when there are many stations with the same broadcast content having relatively strong electric field strength, these stations are conventionally used. The present invention provides an auto-preset device capable of presetting broadcast stations having different broadcast contents having a low electric field strength, which have been masked by the broadcast station.

[Brief description of the drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention, FIG. 2 is a diagram showing an embodiment of the present invention, FIG. 3 is a diagram showing an example of a frequency table, and FIG. 10 is a flowchart of a process. In the figure, 101: high frequency amplifier, 102: mixer, 103: bandpass filter, 104: intermediate frequency amplifier, 105: detector, 106: low frequency amplifier, 107: PLL synthesizer, 502: keyboard .

Claims (1)

(57) [Claims] 1. A receiving station detecting means for scanning a receiving frequency of a radio receiver over an entire receiving frequency range, detecting a receivable broadcasting station, and determining the receiving frequency and the receiving level.
An auto-preset device for a radio receiver, comprising: a frequency storage means for storing each reception frequency and reception level determined by the reception station detection means in association with each preset switch; A frequency table in which the broadcast stations belonging to the same group as the receiving broadcast station detected by the receiving station detecting means are already stored in the frequency table; and When the means determines that a broadcasting station belonging to the same group as the receiving broadcasting station is already stored, the broadcasting station having the smaller reception level of both broadcasting stations is provided with an auto presetting means that does not store the broadcasting station. Auto-preset device for radio receivers.