JPH04103226A - Rds receiver - Google Patents

Abstract

PURPOSE:To surely select a station whose reception state is best by receiving a preceding reception station when a network recognition code between a best station and the preceding reception station is dissident. CONSTITUTION:Whether or not a frequency data in a best station memory is coincident with a preceding reception frequency is discriminated and when the frequencies differ from each other, whether or not a PI network recognition code of the best station and that of the preceding reception section are coincident is discriminated, and when the PI code is coincident, the reception of the best station is kept received. When the reception frequency is selected to other same network station frequency based on a frequency information code data of an AF network station group, the reception state of the same network station frequency group in the AF memory is discriminated by one switching operation. Thus, the best station is surely selected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a radio data system receiver (RDS receiver) implemented in Europe.

[Conventional technology]

Generally, when a broadcast station broadcasts, information related to the program content is transmitted as data using multiplex modulation, and the receiving side demodulates this data and selects the desired program content based on the data. There is a Radio Data System (RDS) that enables the service to be provided to the public.The data of this RDS includes the network identification code (P,1), the traffic information station identification code (TP), and the traffic announcement L! ! There are identification codes (TA), program service name information codes (PS) such as broadcasting station names and network names, and frequency information codes (AF) of network stations broadcasting the same program.

By the way, in the case of a vehicle-mounted receiver, the reception condition of the broadcast wave being received may deteriorate as the vehicle travels. However, in the case of RDS broadcasting, as mentioned above, it is possible to obtain the AF data of a group of network stations broadcasting the same program, so by storing this AF data in memory, it is possible to It is possible to select another station on the same network that has a large bell (electric field strength).

[Problems to be Solved by the Invention] In the above-mentioned RDS receiver, there is a reception frequency selection method that does not cause audible discomfort in the reception state when selecting stations within the same network, as disclosed in Japanese Patent Application No. 63-25904.
It is proposed in No. 0. However, the above method detects the presence of the current receiving station and one of the receiving stations of the same network station frequency group supported by AF data from the current receiving station, and then sends each received signal to the current receiving station. This is a method in which the station compares the radio signals, detects the presence of the receiving station again, and then switches to the receiving station.Switching must be performed several times before switching to the best station in the area where the vehicle is traveling. There was a problem that it had to be done.

This invention was made to solve the above-mentioned problems, and its purpose is to provide an RDS receiver that can reliably tune to the station with the best reception condition with a single switching operation. shall be.

[Means for Solving the Problems] The RDS receiver according to the present invention determines the reception conditions of all the frequency groups of the same network stations obtained from received waves and stored, and selects the station with the frequency with the best reception condition. determining whether the network recognition code of the best station matches the network recognition code of the original receiving station;
This is provided with a means for receiving the original receiving station if there is no match.

(Function) In this invention, the reception conditions of all the frequency groups of the same network stations obtained and stored from the received waves are determined, the station with the best reception condition is received, and the best station and the original reception condition are determined. Receive the original receiving station if the stations' network identification codes do not match.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. 1st
The figure shows the configuration of the RDS receiver according to this embodiment, and the FM multiplex broadcast waves received by the antenna 1 are transmitted to the front end 2.
A desired station is selected, converted to an intermediate frequency (IF), and then supplied to the FM detection section 3. front end 2
is controlled by a PLL circuit 6 including a programmable frequency divider, and is configured to perform channel selection by setting a frequency division ratio using a controller 10. The detection output of the FM detection section 3 is supplied to a multiplexer demodulation circuit (MPX) 5 via a noise canceller (NK) 4, and is separated into L (left) and R (right) channel audio signals in the case of stereo broadcasting. , the audio is output via the audio mute section 12. Note that the audio mute section 12
is configured to be turned on and off by the controller 10. Also, the detection output of the FM detection section 3 is 57KHz.
The signal is input to an RDS decoder 9 via a bandpass filter 8, and is converted into distinguishable data by a controller 10. The controller 10 receives receiving station information (PI
TP, TA, PS, AF, etc.) and store them in memory 11.
I remember it. Further, a level detection section 7 is provided which detects a reception signal (electric field strength) based on the IF signal level, and the reception signal detected by the level detection section 7 is supplied to the controller 10. .

Next, the automatic channel selection operation of the RDS receiver executed by the controller 10 will be explained with reference to the flowchart of FIG. It is assumed that AF data for one or more stations already exists in the storage area in the memory 11. Table 1 shows the AF data list f1 to f1 stored in this storage area.
An example of... is shown below.

Table 1 First, in step S1, the audio mute 0I112 is turned on, in step S2, PI data representing the receiving frequency of the broadcasting station currently being received and the network of the receiving station is held, and in step S3, the receiving signal level and receiving frequency are held. is written in the corresponding area in the best time memory shown in Table 2.

Table 2 Table 2 shows an example in which the receiving frequency f3 and the signal level ■1 when receiving this f are stored. In step S4, n=0, in step S5, n=n+1, and in step S6, A
The AF data is read out and AF stations are received according to this data. In step S8, a received signal bell is detected and compared with the signal level in the best memory. If the signal level at the receiving station is higher than that in the best time memory, the process advances to step S9, and the receiving frequency, reception signal, and bell are written in the corresponding area in the best time memory. If the signal level of the receiving station is higher than that of the best memory, the contents of the best memory are not rewritten.

In step S10, it is determined whether n is the final one, and if it is not the final one, the above procedure is repeated. In other words, the process is repeated until all received signals and bells of the AF frequency group in the AF memory are detected. When n becomes final, i.e. all A
When the detection of the F frequency group is completed, the frequency data in the best memory is received in step $11, and the audio mute is canceled in step S12. In step 513, it is determined whether the frequency data in the best frequency memory matches the original receiving frequency. If they are different, in step S14, it is determined whether the best frequency data and the P1 code of the original receiving station match. If the PI codes match, the best time signal will continue to be received. P.I.
If the codes do not match, the audio mute is turned on again in step S16, the original reception frequency is received in step S17, and the muting is canceled in step SIB. Also, if it is determined in step S13 that they are the same, it means that there is no other station with better reception conditions on the same network frequency, so reception is performed without checking whether the PI codes match. Continue to do so.

In this way, when switching the reception frequency to another same network station frequency based on AF data, the reception status of all the same network station frequency group in the AF memory is determined with a - degree switching operation, so it is ensured that the best You can switch between. Furthermore, as shown in step S12, since the audio mute signal is canceled before the PI code match is recognized, the audio mute time is shortened by the receiving station's PI detection time, and the audible discomfort can be reduced. can.

〔Effect of the invention〕

As described above, according to the present invention, the reception conditions of all the frequency groups of the same network station obtained from the received waves are determined, and the station with the best reception condition is received. It is possible to reliably switch to the best time by switching operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are a block diagram of an RDS receiver according to the present invention and a flowchart showing an automatic channel selection operation. 2...Front end, 3...FM detection section, 5-1
．． Multiplexer demodulation circuit, 6...PLL circuit, 7.
...Level detection section, 9...RDS decoder, 1o...
・Controller, 11...Memory.

Claims (1)

[Claims] means for receiving RDS broadcast waves including frequency information codes and network recognition codes of the same network station group; means for storing the received frequency information codes and network recognition codes; means for determining reception conditions and receiving the station with the best frequency; determining whether the network recognition code of the best station matches the network recognition code of the original receiving station; An RDS receiver comprising means for receiving an original receiving station.