JPH03210496A - Time data detector of fm receiver - Google Patents

Abstract

PURPOSE:To eliminate a wrong time indication and a time adjustment by making a counter step forwardly everytime detecting coincidence of presumed time data with time data received thereafter, and by judging and outputting the received time data corresponding to a time when counted value of the counter becomes larger than a specific value, as correct time data. CONSTITUTION:Just when one time data is received, a timer 22 starts, a time data which is to be received thereafter, is presumed from a counted value of the timer 22 and the one time data, and the presumed time data and the aforementioned time data which is to be received thereafter, are compared by a comparator measure 23. A counting measure 19 steps forwardly everytime when the comparison result coincides, and the received time data corresponding to a time when the counted value of the counting measure 19 becomes larger than a specific value, is output as a correct time data.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention is provided in an FM receiver that receives FM broadcast waves in which time data is superimposed on frequency components other than the main signal component.
The present invention relates to a time data detector that detects correct time data from received time data.

``Prior art'' In Europe, frequency components (subcarriers) other than the positive signal component of FM broadcasting are subjected to two-phase PSK modulation with data, and the data is broadcast on FM.
Various types of data are broadcast by adio Dat, a System). In this RDS, one group is composed of four blocks each consisting of 26 bits. 4th pro.

Due to this, time data is broadcast every minute. F
The RDS demodulation section of the M receiver demodulates the RDS data, further detects the RDS code, decodes the time data using the time data decoding means, displays the time data as it is, and the user can read the displayed time. They would either adjust the time on their own watch or car clock, or automatically adjust the time on their car clock using the received time data.

``Problem to be solved by the invention'' FM broadcast waves undergo multiple propagation in mountainous areas or urban areas, or are affected by external noise, resulting in errors in the received time data. Even if I made a mistake, it would continue to display the time and then automatically adjust the time. This may result in an incorrect time being displayed or
Incorrect time adjustments were sometimes made.

According to the invention of "Means for Solving the Problem J Claim", when one piece of time data is received, a timer is started, and the time data is then received based on the counted value of the timer and the one time data. Time data is estimated, and the estimated time data and the time data received thereafter are compared by the comparison means, and each time the comparison results match, the counter means is incremented, and the count value of the counter means is set to a predetermined value. The reception time data corresponding to the time when the value exceeds the value is output as correct time data.

According to the invention of claim 2, when one piece of time data is received, a timer is started, the one piece of time data is stored, and the time difference between the stored time data and the subsequently received time data is determined. The time difference and the counted value of the timer are compared by the comparing means, and each time a match between the two is detected, the counter means is incremented, and this corresponds to when the counted value of the counter means exceeds a predetermined value. The received time data is output as correct time data.

"Embodiment" FIG. 1 shows an embodiment of the invention of claim 1. FM receiver 1
1, the FM broadcast wave received at 1 is FM demodulated, its main signal component is supplied to the speaker 13 through the amplifier 12, and the subcarrier component in the FM demodulation output is sent to the bandpass filter 14.
The output is two-phase PSK demodulated by a phase demodulator 15, and the demodulated output is sent to an RDS code demodulator 16 to determine which bit of which block each focus corresponds to, and then supplied to a microcomputer 17. Within the frame of the microcomputer 17, only the parts related to the present invention are shown as functional blocks.

When the time data in the RDS is received, the time data decoding means 18 decodes the time data to hour 2 minutes, and the processing routine shown in FIG. 2 is operated to determine whether the time data is being received for the first time or not. In other words, it is checked whether the count value of the counter means 19 is O (S,
), in the case of the first time, the received time data is stored in the register 21, the counter means 19 is preset to 1 (SZ), and the timer 22 is started (
S3). Every time the timer 22 counts one minute, the register 2
1 minute is added to the time data of 1 (S4). This step S4 is performed in the main routine. In this way, the estimated value of the time data received thereafter is stored in the register 21.
can be obtained.

Next, when time data is received, since the counter means 19 is set to I in step SI, it is determined that this is not the first reception, and this received time data and the estimated time data in the register 21 are compared to the comparison means 23. When the two match, the counter means 19 is incremented by 1 (S6), and it is determined from the counted value whether it is the second reception, that is, whether the counted value of the counter means 19 is 2 (st), and the second time In the case of reception, the process moves to step S4, that is, the main routine.

Further thereafter, when time data is received, step S,
It is determined that it is not the first time, and the received time data is compared with the estimated time data in the register 21 (S,). If the two match, the counter means 19 is incremented by 1 and becomes 3 (S6), and this total Rather than the second reception from the number,
It is determined that this is the third reception (S,), and in this example, 1
If the estimated time data matches the two consecutive reception time data from the first reception, the second reception, and the third reception, the reception time data at that time is determined to be correct data and is output. (S,), for example, when decoded by the time data decoding means 18, each minute value is inputted to the display 25 through the gate means 24 to display the time. Alternatively, the time on the car clock is automatically corrected using the received time data at this time.

The counter means 19 is reset and this routine is ended (S,).

If the received time data and the estimated time data in the register 21 do not match in step S, the process moves to step SO, at which time the received time data is stored in the register 21 and the counter means 19 is preset to 1. Therefore, if a mismatch occurs, the reception time data at that time will be processed as the first reception data.

Instead of adding 1 minute to the data in the register 21 every time the timer 22 counts 1 minute, the time data in the register 21 and the counted value of the timer 22 are added each time time data is received to obtain estimated time data. , and the reception time data may be compared in step Ss. It is also possible to output correct time data when the count value of the counter means 19 is 2 or 4 or more.

Furthermore, when time data is first received, a timer is started for a predetermined period of time, for example, 10 minutes, and each time the estimated time data and the received time data match, the counter is incremented by 1, and when they do not match, the register 21 is rewritten and the counter is If the preset is not performed and the count value of the counter is a predetermined value, for example, 3 or more after 10 minutes have elapsed, the estimated time data at that time is output as correct time data. Or 10
When the count value of the counter reaches a predetermined value, for example 3, within minutes, the reception time data at that time may be output as correct time data.

FIG. 3 shows a processing flowchart of an embodiment of the invention according to claim 2.

When time data is received, this processing routine is entered, and first, it is checked whether it is the first received data or not, for example, by checking whether the count value of the counter is 0 or not (S,). The time data is stored in the register, a counter is preset to 1 (St), a timer is started (S3), and the process returns to the main routine. Next, when time data is received, the count value of the counter is 1 and it is not the first reception, so the process moves to step S4, where the time difference between the received time data and the time data stored in the register is calculated. It is checked whether the time difference and the count value of the timer match (SS), and if it is defeated, the counter is incremented by 1 (S6), the count value becomes 2, and the received data is changed to 2 by this value. It is checked that it is the third time, and the process returns to the main routine (S,). When the next time data is received, it is determined in step Sl that it is not the first reception since the count value of the counter is 2, and the time difference between this received time data and the time data stored in the register is calculated (Si , it is checked whether the time difference matches the count value of the timer (Ss), and if they match, the counter is incremented by 1 (56), and the count value becomes 3, and it is not the second reception but 3. It is determined that this is the second reception (S,), the reception time data at that time is output as correct time data (Ss), and the counter is reset and the process ends (S,).

If the time difference calculated in step S and the count value of the timer do not match, the process moves to step St, the reception time data at that time is stored in the register, the counter is set to +1, and this reception time data is set to 1. It will be processed as the second reception. If the count value of the counter is 2 or 4 or more, it can also be considered as correct reception time data. Also, within a predetermined period of time, for example 10 minutes, after receiving the first time data, the counter is incremented every time the calculated time difference and the count value of the timer match, and even if they do not match, the time data in the register is not updated. Without presetting the counter to 1,
The reception time data when the count value of the counter reaches a predetermined value, for example 3, may be taken as the correct time data. Alternatively, if the count value of the counter is greater than or equal to a predetermined value after a predetermined time has elapsed, time data obtained by adding the time data of the register and the count value of the timer at that time may be output as correct time data.

"Effects of the Invention" As described above, according to the present invention, when time data is received, the timer is used to estimate the time data that will be received later, and the estimated time data and the time that will be received later are used. If the data matches once or multiple times, it is assumed to be the correct time data, or when the time data is received, a timer is used to estimate the elapsed time until the time data that is subsequently received, and this estimated elapsed time and Reception time data and 1
If the time difference with the second time data matches once or multiple times, it is considered correct time data, so even if time data is received incorrectly due to propagation conditions, the incorrect time data can be processed as correct time data. That's not it.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the invention according to claim 1, FIG. 2 is a flowchart showing an example of its operation, and FIG. 3 is a flowchart showing an example of operation of the embodiment of the invention according to claim 2.

Claims (2)

[Claims] (1) A time data detector installed in an FM receiver that receives FM broadcast waves in which time data is superimposed on frequency components other than the main signal component, and that detects correct time data from the received time data, Time data 1
a timer that is started when the timer is obtained; a time data estimating means for estimating the time data to be received thereafter from the counted value of the timer and the one time data; and the estimated time data of the time data estimating means and the above one time data. a comparison means for comparing the time data received by the comparison means, a counter means incremented each time the comparison means detects a match between the two data, and a count value of the counter means exceeds a predetermined value. A time data detector for an FM receiver, comprising: means for determining and outputting reception time data corresponding to as correct time data. (2) A time data detector installed in an FM receiver that receives FM broadcast waves in which time data is superimposed on frequency components other than the main signal component, and that detects correct time data from the received time data, Time data 1
a timer that starts when the above-mentioned one time data is obtained; a means for calculating the time difference between the stored time data and the time data received thereafter; and a time difference between the time difference and the counted value of the timer; a counter means that is incremented each time a match is detected by the comparison means; and a counter means that increments the received time data corresponding to when the counted value of the counter means exceeds a predetermined value. A time data detector for an FM receiver, comprising: means for outputting a determination as time data; and a time data detector for an FM receiver.