DK175376B1 - Method of utilization on the receiving side of digital information transmitted in a radiophone signal - Google Patents

Description

in DK 175376 B1

The invention relates to a method as set out in the preamble of claim 1.

Methods of the kind mentioned above are e.g. described in the technical document "Doc. Techn.

5 no. 3244 "from the European Broadcasting Union. In the radio data system (RDS) specified, the transmission of additional information, such as the transmission of - Alternative frequencies (AF-Code), in particular in the form of alternatives summarized in lists, is used. This information is of interest, both at mobile reception (for example, with car radios), for example when leaving a transmitter's radiation area and at stationary installations, f. For example, in case of outage 15 or interference with a transmitter, with appropriately designed receivers with storage, such lists can be stored, whereby the time for tuning the transmitter at the optimum frequency in this list at all times (eg according to optimum reception conditions) can be reduced.

The RDS data signal also contains, inter alia, a so-called program identification information (Pl-Code), whereby it is possible, directly by means of the AF-code and indirectly, by means of the PI-code, to ascertain the 25 alternative transmission frequencies at which the currently received program signal can also be received .

Exploitation on the receiving side of the alternate transmit frequencies can be done in such a way that the recipient is briefly, successively ascertained on the alternate 30 frequencies for each alternate frequency. Then the receive field strengths are compared for the alternate frequencies and for the currently received frequency, after which that frequency is selected and used as new

I DK 175376 B1 I

I I

In receive frequency that gives the largest measured receive I

In field strength (this can of course also be the one)

I to set receive frequency). IN

In this, however, the problem arises that you

In 5 there are cases where the measurement of the receiving field strength, I

Especially at multi-way reception, do not give anything- I

In passionate statement about the quality of the reception. In the case of multiple I

In road reception, they are caused by signal reductions.

In the reception disorders dependent on the detour, by I

In 10 the instantaneous signal equipment (determined by I

In the program type, e.g. classical or pop music)

In and on mobile receipt of vehicle speed. And I

In receive signal interrupted by multipath reception,

You can despite a relatively high receiving field strength between

In the 15 signal reductions subjectively I feel extremely

You are disturbed, whereas a reception signal that is only you

In disturbed by wheezing, can feel significantly better. IN

As a result, the stated selection of the I

In the best possible reception of a selected program signal, I

In 20 years, the reception is constantly harmed by multiple people

In road disruptions. This undesirable result is possible

You do not significantly change the fact that e.g. using I

In another tuner in the receiver for a longer meal time

You set the alternate frequencies and measured them

25 receive field strengths are integrated as they are used in multi-way modes.

In reception, received signals also interfered with an I

In such integration, as a rule, a greater throughput

In average receiving field strength than the received signals,

In which is only disturbed by the rush. IN

However, such disruptions can not only harm you

In the program signal. Also the additional ones, e.g. in RDS-I

Information transmitted in the data stream can be damaged here

You know, so that on the receiving side under certain circumstances

I DK 175376 B1 Standings can either result in long waiting times, until correct RDS information is again available, or for misinterpretation. This is particularly evident in data whose repetition cycle in the data stream is relatively long.

I A further problem regarding the program signal quality is caused by the transmission network structure in some countries, especially countries with overlapping networks in the transmission network. Since they transmitted 10 digital information by a main transmitter centrally, e.g. a list of alterna-

In tive frequencies, in some circumstances not fit

You look at it by relay reception from the main transmitter. IN

In these bishops (for example, converters) they must be filtered out

It is the relay receiver and replaced by the one for the relay

In the 15th clandestine list in force. This filtering and I

Reinstatement is associated with an increased auction. IN

In addition, the quality of the program signal improves

You are called by the filtration. IN

I It has therefore already been proposed (DE pa- I

I 20 Tent No. 34 32 848) for all transmitters in a late I

In your group to send out a series of lists of alterna- I

In tive frequencies, each of these lists at the beginning

In the part, the operating frequency of the one to the I

In the list in question attached transmitters, for from the series of I

25 lists to be able to select it at any time, I

and to the received sender optimized list. IN

A safe reception of such a series of li- I

however, it presupposes that it subsequently as "ho- I

at "designated beginning of each list of operating I

30 frequencies for the transmitter associated with the list, receive I

is given correctly. If this is not the case, e.g. as in

due to interference due to multi-way reception- I

see, they can follow the head of each list following al- I

I DK 175376 B1 I 4 I ternative frequencies are not utilized on the receiving side, nor when they are received correctly, as there is no proper connection to the operating frequency in question.

5 It has therefore already been proposed (company H and Blaupunkt-Werke GmbH, Hildesheim) to transmit in all the alternate frequencies for a transmission chain, which may consist of several transmission groups (eg BR-north and BR-south), in the form of a matrix, the alternate frequencies of each transmitter being grouped as matrix neighbors in the matrix. However, this so-called "matrix method" has the disadvantage that, as a result of the grouping regulations, it is not possible to avoid neighbors who in reality do not have alternative frequencies in the sense given above, so that on the receiving side, take similar wrong votes to such neighbors. In addition, setting up and modifying an H matrix is extremely complicated, so re-coating a released transmit frequency cannot be possible because an existing matrix does not allow such an H change.

H The invention is intended to provide an improvement in H quality of reception quality by methods of H of the type mentioned initially.

H 25 This task is solved by the measures set out in claim 1.

H The invention is based on the recognition that the reception H quality can be improved by transmitting the alternative H frequencies so that they can be associated with the higher transmit frequency frequencies with greater certainty. This has the advantage that, if H is needed, the receiver can be tuned more quickly to an alternate frequency that provides better reception.

5 DK 175376 B1

This is true even if the receiver has only a small storage capacity.

The invention is further based on the recognition that the reception quality can be improved by the fact that the reception field strength is not used, or at least not exclusively, in the reception field strength, but acoustic and / or program signal distortions.

This has the advantage that alternative frequencies which only "appear", namely because of a higher 10 field strength, provide a better reception, but in fact the user feels inferior, can be rejected on the receiver side.

If the additional data transmitted within the radiophone signal, as in the case of RDS data signals, is in the form of digital information, the bit errors in the RDS data signal can be used as a measure of the program signal distortion. Namely, it has been found that the bit errors in the RDS data signal correspond relatively accurately to the program signal distortion, although the program signal 20 is transmitted in the baseband from 0 to 53 kHz and the RDS signal on a 57 kHz carrier with a frequency swing of at least ± 1.2 kHz.

Because of this correlation, upon further development of the invention, it is possible to take advantage of the fact that interference from multiple path sampling or interference produces sudden occurrence of bit errors in the RDS data signal, whereas interference resulting from noise causes uniformly distributed bit errors. The degree of all interference is thereby derived from the block error rate which can be ascertained completely independent of the data content.

For optimal selection of the frequency that allows the best instant reception, stay in

I DK 175376 B1 I

I I

In the beneficiary on this basis, successively aligned to I

In the alternate frequencies, and to the set I

In reception frequency for consecutive time

At intervals. In a somewhat more comfortable receiver con- I

In the 5 structure, there is an optimal selection of I

At the frequency that gives the best instant counter- I

receiver, another tuner in the receiver that successively I

You are tuned to the alternate frequencies and tuned

I set the receive frequency of the first tuner, in in- I

In 10 intervals of e.g. at least 2 sec. IN

Below these - at the receiver construction with 2 I

In tuners relatively long tuning intervals

The bit errors are found for the total RDS I received

In data signal (in addition to the alternative frequencies in- I

In 15, they provide a wealth of additional information). I to- I

In conjunction with this, they are utilized freely for each alternative

In the case, and for the instantaneous reception frequency, I-

In stated bit error distributions and block error rates

In the following way:

I 20 If all the frequencies investigated contain only I

suddenly appearing, or only uniformly advantageous

In te bit errors, which means that you know

In all frequencies, reception signal interference occurs

As a result of multi-way reception, interference or

In 25 sus, the corresponding block error rates I are compared

You with each other, after which the frequency that it has- I

At the west block failure rate, is selected as the optimal I

receive frequency. Receiver tuner or - in case I

of a receiver with two tuners - the first tuner of I

30 is then tuned to this selected frequency, provided that I

the already set reception frequency is not I

identical to the selected frequency. IN

In the case where the frequencies examined I

7 DK 175376 B1 exhibits various disturbances, ie both bit error due to wheeze and bit error due to multi-way reception, first the frequencies which are substantially disturbed by wheeze and not by 5 multi-way reception, are selected first. the frequencies with essentially uniformly distributed errors. To exclude highly suspicious signals, only such frequencies can be preselected if RDS data signals do not exceed a maximum permissible block error rate.

10 Then the preselected frequencies are compared with respect to their detected block error rate and the frequency with the minimum block error rate is selected as the optimal receive frequency.

Said selection of the optimum frequency 15 can, at sufficiently long measurement intervals for each alternative transmitting frequency, be made without regard to the receiving field strength concerned. In particular, at smaller measurement intervals, the receiving field strength can also be included in the selection, as the weighting between the receiving field strength on the one hand and signal distortions on the other can be determined empirically.

The alternative frequencies can be ascertained using the PI code or the AF code or during use and possibly combination - in case of multiple ambiguities or incomplete transmission of both codes. The PI code identifies the frequencies at which the same program signal can be received. By comparing the PI Code with transmitter scanning, a clear association can be obtained between the instantaneous receiving frequency and its alternate frequencies. This association can be derived immediately from the AF Code. If the AF code is not transmitted in the RDS data signal or if the AF code is faulty, the alternative

I DK 175376 B1 I

I I

In frequencies are derived from or supplemented by the PI Code. IN

By the method of the invention,

This is possible for the first time with a completely new one

In idea of finding optimum reception quality

I 5 to realize them by the introduction of the RDS system and the I

In it, alternative frequencies contained therein sought

In the advantages of a sustained optimal reception in radio I

In phonics receivers (both mobile and fixed radiophone receivers)

I do). By means of the RDS data signal, hereby, the pro- I

In the 10 multi-way receivers of the utility signal on I

In a surprising way, significantly reduced. IN

A further embodiment of the method I

The invention is characterized in that by the series I

I of individual lists contained in the digital I

In 15 information in the RDS then enter the escape and contain them for I

In the individual transmitters in a transmitter chain, or

Alternative frequencies optimized for these transmitters,

You transfer it to each list or to each I

In list corresponding operating frequency of the corresponding sen- I

In 20 there, not only at the beginning of the list, but also

I before each alternative frequency in that I

In list so that each alternate frequency "address- I

In res "with the operating frequency. Each list thus consists of I

In a series of digital information blocks, each consisting of

In 25 of two information. One of these information in I

In each block (except for very special exceptions - I)

You see), the operating frequency of the one for that li- I

You hear the transmitter. If for part of the list I

If you are transmitted or received incorrectly, they can be properly received

In 30 alternative frequencies taken as a result of their pairing

In ring with the operating frequency, uniquely associated with it

In the corresponding transmitter, and therefore on the receiving side, I

You are in his list. Since it is unlikely that in I

9 DK 175376 B1 a considered list is constantly interrupted by the same information block, a complete 5 list can be stored from two or three successively received interrupted lists for the same sender on the receiving side.

The stated pairing of each alternate frequency with the operating frequency of the transmitted list increases, in comparison with the method of DE Patent No. 34 32 848, the number of frequency information transmitted for each 10 list to double, thereby increasing the cycle duration for each row of lists. corresponding. Therefore, one would think that the reception probability and safety of such an extended cycle duration would rather be diminished than improved. In fact, for the above-mentioned matrix method, advantage is applied to the list method according to DE Patent No. 34 32 848, a smaller cycle duration for a matrix over a number of individual lists, and from this a higher reception security can be deduced.

It should therefore be surprising to the art world that, despite the significant increase in cycle duration in the range of lists performed according to the invention, the reception security is considerably greater than in the matrix method and the known list method. The unforeseeable reason for this surprising advantage lies in the fact that due to the described addressing of each alternate frequency with the operating frequency, even in extremely poor reception conditions, a secure association of the correctly received alternative frequencies is possible, which is not the case with the other methods so that their shorter time cycle in such receiving situations does not

DK 175376 B1 I

use something. IN

The invention is explained in more detail below

with reference to three embodiments shown in the drawing

six examples, in which I

5 FIG. 1 is a schematic representation of that of I

each transmitter in a transmitter chain radiated row of li-I

alternate frequencies according to one

first embodiment of the invention;

FIG. 2 is a circuit diagram of a receiver for I

10 for use in connection with a method according to another one

the embodiment of the invention and I

FIG. 3 is a circuit diagram of a receiver for I

use in connection with a method according to a third embodiment of the invention.

In FIG. Figure 1 is a schematic representation of a system of alternative lists that are sent as extra information

from a radio transmitter. In the considered example, you go

there from a radiophone signal in which a 57 kHz auxiliary carrier is inserted. The auxiliary carrier may contain an amplitude modulation having content

a traffic sign. As modulation or as additional I

For more modulation, the auxiliary carrier is printed on a data I

signal that is encoded in a particular way that is here

without interest. This data signal is transmitted in accordance with I

25 voting form of all transmitters in a transmitter chain I

with the same program, e.g. of all transmitters in

the "Bayern 3" transmitter chain in the Baye-I supply area

risks Broadcast (abbreviated: BR). The assent I

transmitted data signal contains, inter alia, a number of lists I

30 over alternative frequencies for all transmitters in I

the transmitter chain, in this case the list for I

transmitter # 1, list for transmitter # 2, list for I

transmitter # 3 until the list for transmitter # 29 for I

11 DK 175376 B1 in case the transmitter chain has 29 transmitters. Each list is adapted to that transmitter and contains the alternate frequencies for that transmitter, that is, the frequencies of the transmitters in the receiving region of that transmitter from which the same program can alternatively be received. Eg. Alternatively, the "Bayern 3" program in the Miinchen area can be received from the transmitter "Wendelstein" or the transmitter "Ismaning". If the receiver is set to the transmitter "Wendelstein", the receiver can with a reception deterioration, e.g. due to multipath reception, due to the knowledge of the "Ismaning" alternative, is briefly tuned to reception from "Ismaning" and this transmitter's receive field strength can be measured. If the latter is the best one, 15 is switched to the "Ismaning" transmitter and this sub-. renunciation is practically inaudible to the listener.

Each list consists of a series of digital information blocks, which in FIG. 1 is indicated as horizontal lines within the list. Each information block 20 consists of a pair of information, as indicated by the vertical division of the list into a left and a right half. The first "major" block in each list contains in the left block half the number of the alternate frequencies within that list. In the list of transmitter # 1 with four alternate frequencies, the head contains the number 4, in the list of transmitter # 2 9 with seven alternate frequencies, the head contains the number 7. In the right block half, the head of each list contains the operating frequency of the one to the list. responding sender.

In the list of transmitter # 1 with the operating frequency 98.5 MHz, the frequency information 98.5 MHz is indicated in the right half of the head. In the transmitter list

I DK 175376 B1 I

I 12 I

No. 29 with the operating frequency 97.9 MHz, is transmitted in the main I

knew the frequency information 97.9 MHz. IN

So far, consistency with the future

procedure according to DE Patent No. 34 32 848. I I

In this case, the following is transmitted to the head

two blocks in each list alternate frequencies, I

so that in the case of list # 1 with four I

alternate frequencies, following the head follows two blocks

ke with 2x2 «4 alternate frequencies. IN

10 In contrast, it transfers by the I

I. lying embodiment of the invention in each I

after the block following the block corresponding to the list I

In operating frequency along with an alternate frequency. IN

This pair thus contains the operating frequency as I

I address for the alternative frequency concerned,

which has the advantage stated above that operational reliability

the security is drastically increased, although the number of those for I

In each list necessary blocks that follow the main I

In it, doubles. IN

20 In the list for transmitter # 1, therefore, after I

head instead of two blocks, as per DE I

Patent No. 34,328,484, now transferring four blocks, I

resulting in a corresponding increase in transfer

In the ringing time for the series of 29 considered lists. Then I

H 25 this transfer time is equal to the cycle duration of I

In every row of lists, one might think that the receipt- I

In the realm of transmission disorders you would be

deterioration as a result of this extension of cycle I

H the duration. However, this assumption is, as already mentioned

In 30, wrong, so that it turns out to be overpriced

effect that, in the method of op

the find according to this embodiment, I

In spite of the extension of the cycle duration, a clear I

DK 175376 B1 13 improves the reception security in relation to the list method and the matrix method.

In the case of transmitters whose operating frequency is not in the 100 kHz raster but 5 in between (so-called offset frequencies), e.g. 92.85 MHz, is transmitted at the head of the list in question, not the frequency of operation, but a special information, a so-called "fill code" according to the above-mentioned document from the European radio station. In the subsequent block, the offset frequency is first transmitted, e.g. 92.85 MHz, and then a qua page frequency, e.g. 92.8 MHz. This quasi-drift frequency is transmitted in the following blocks in the first position as the address of the alternate frequencies.

15 A further deviation from the transfer rule specified in the drawing for the individual lists will appear if one of the alternative frequencies is an offset frequency. In this case, in the block in question, instead of the operating frequency, the offset frequency of the alternative frequency is transmitted together with the quasi-alternative frequency contained in the 100 kHz raster.

For identification of alternative frequencies for such transmitters which, within the framework of regional programs, for some periods of time within a transmit day or transmit week, are disconnected from the corresponding transmitter chain, e.g. transmitters there from 7 p.m. The program "Bayern 3" will be broadcast from 6:00 to 12:00. 12 noon to 1.30 pm regional program "Neues aus Schwaben" and from 30 at. From 13:30 to 24:00 the program "Bayern 3" again, it may be appropriate in the corresponding block to change the order of operating frequency and alternative frequency, ie first to transmit the alternative I frequency and then the address "operating frequency".

Each list is customized to that transmitter

and contains similar to the agreement within I

the European radio station a maximum of 25 frequencies, i

5 rule significantly fewer. At the beginning of each list

the operating frequency of the corresponding transmitter, ie. IN

In the list for transmitter # 1, it says at the beginning I

the operating frequency of transmitter # 1, e.g. 98.5 MHz. IN

As mentioned, the displayed row of 29 lists is transferred from I

10 each transmitter in the transmitter chain as a data signal. IN

The recipient receives and decodes the transmitted I

In data signal, i.e. the series of lists of alternatives I

In frequencies. In order to select it for the eye,

In the eye tuned send valid list from the receiving I

15 of a series of lists, the recipient simply needs to compile

comparing the first frequency in each list with the I

instant voting frequency, which even at I

In 29 lists can be completed in a very short time. This

Selection can be either in-line or off-line

20 line operation, ie. without or with intermediate storage of it

In received row of lists. In a preferred embodiment

In selected form, the selected list is stored in all cases.

In processing the received and possibly intermediate row of lists, the receiver 25 selects the list whose first frequency (equal to the operating frequency of the corresponding transmitter) corresponds to the instantaneous tuning frequency.

If the first frequency for several lists matches I with the set operating frequency, all these I 30 lists must be selected. Only the selected list (s) is used for the subsequent optimization of the voting.

In This tuning process, either by an appropriate listener sends orders from the listener or automatically, e.g. when the currently received transmitter is no longer received satisfactorily. In the tuning process, the receiver is automatically tuned to the alternate frequencies listed in the selected 5 list (s) and selects the alternate frequency that provides the best possible reception. By means of the transmitted data signal RDS, a fast optimization of the tuning of mobile receivers can also be carried out for transmitter chains with more than the specified maximum number of alternative frequencies, without requiring filtering out and re-storing of frequency lists at the position of the transmitters.

FIG. 2 shows a block diagram of a receiver 15 for a method according to another embodiment of the invention. In this connection, reference is made to the FIG. 1, although in this second embodiment it is not essential whether the additional information is transmitted in digital form.

The radiophone signals received with an antenna 1 containing additional data are fed to a tuner 2 and a tuner 3. The tuner 2 is part of a radio receiver receiver with an intermediate frequency amplifier 4 for the intermediate frequency delivered by the tuner. a detector 5 for producing the low frequency signal, and an amplifier 6 for the low frequency signal as well as with a loudspeaker 7 for acoustic reproduction. For the signal path, e.g. to the output of the tuner 2, a coupler 10 is connected to select the 57 kHz carrier and connected to a coupler 11 to generate the data. This data is added to a store 12. In this store 12 the alternatives are constantly loaded

I DK 175376 B1 I

I 16 I

In frequencies (AF) of the transmitter received with tu- I

below 2. I

In Tuner 3 serves for the continuous scanning of I

the frequency range that can be received by the tuner 2. The I

5 high and medium frequency output signals from the tuner 3 I

the storage 12. The tuner 3 of the I-I

typed frequencies are constantly compared to those I

corresponding stored frequencies for provision I

of an indication of the transmitter that you currently can

10 are best received. The frequency that the tuner 3 must set

You set is determined by the storage 12 by means of an I

microprocessor 13 over a line 14, and the tuner 3 I

You are matched accordingly. IN

A coupling 15 serves to measure the field strength I

In 15 for each received transmitter. As soon as the field strength measurement I

You show that the signals from another transmitter have a larger I

more field strength than the signals from the transmitter I tuner

2 is set to, the tuner 2 is switched over a link I

16 to the sender who currently has it

In 20 greatest field strengths. IN

In the coupling described so far, it is mu-

It is obvious that due to interferences, e.g. so- I

forms caused by reflections occur

distortions of the acoustically reproduced audio signal. So- I

25 such interferences occur mostly in the vicinity I

In of very powerful transmitters. Also, as a result of I

In a large field force at the immediate receiving point,

You enter an overpower of the recipient, by which you

In acoustic rendering distorted. IN

I 30 At a e.g. from DE patent specification 34 48 043 I

In the known method it is possible to select a late I

In a fully automatic poll without the user's consent

In the works it sends with the same program that on I

The instantaneous receiver position is best received, i. has the greatest field strength.

For this purpose, each transmitter will not only radiate its own list, but also sequentially the lists 5 for all other transmitters in the same transmitter chain, the operating frequencies of the individual transmitters being stated at the beginning of the individual lists. Thus, upon receipt of all lists on the basis of its instantaneous tuning frequency, the recipient may select the list for the currently receiving transmitter, comparing the tuning frequency with the first frequency of each list within the list row.

Furthermore, the receiver also notes the alternate frequencies at which, when it leaves the supply area of the currently tuned transmitter, it can continue to receive the same program without the need to examine the alternate frequencies in the other lists. In this way, switching to another transmitter in the same transmitter chain can usually be carried out very quickly.

However, just when receiving transmitters with high field strength, the acoustic reproduction can be distorted. This can be done, for example. due to an overload due to excessive reception field strength, or to interference phenomena due to reflections.

Therefore, in the present exemplary embodiment of the invention, it is provided that it is possible to make a transmitter setting while retaining the automatic switch to other transmitters broadcasting the same program, thereby largely avoiding or reducing acoustic distortions during playback. .

Using a coupler 17, it is generated in ___: _____

I DK 175376 B1 I

in 18 I

In the microprocessor 13 a switching state, whereby I do not

In the most powerful transmitter, but a weaker transmitter, I

In particular, the second strongest transmitter is used for sam- I

Compared to the set operating frequency transmitter. IN

I 5 When designing coupler 17 as reset I

In ling key, it is achieved that the setting of the apparatus on an I

You send with less field strength than the instantaneous I

The highest field strength can be recalled when the transmitter nears

In zone or disturbance zone is abandoned. A repeated I

In the 10 coupling process this is facilitated. The effect of the coupler I

I 17 on the microprocessor 13 can also be configured thus, I

In that all transmitters corresponding to the stored alternative I

In list can be set successively with decreasing field I

In strength by briefly operating the coupler 17 several I

For 15 times. For a longer operation of the coupler I

In 17, e.g. for several seconds, the reset process can be restored

In the cess is triggered. IN

In the tuner 3 of FIG. 2 may have a different configuration

I than the tuner 2, since its actual task alone is off- I

In 20 keying of the frequency band to check any I

In stronger transmitters. Thus, obtaining I is not required

In a signal quality. IN

It is also possible to carry out a field strength

In switching in the form described using I

I have only one tuner, which, however, under question I

In the process, transmitters with inferior field control can be received

I ke. IN

In FIG. 3 shows as a third embodiment Example I

In accordance with the invention, a change of the embodiment shown in FIG. 2

In 30 clutch, where two equal tuners 2 and 3 are switched on

Easily in two separate receiving branches A and B, each of gi- I

I ver a low frequency output signal NFA and NFB to a low I

In frequency couplers 18 passing one of these I

19 DK 175376 B1 two signals for a low frequency amplifier 6 and a loudspeaker 7. From the tuner 2, the data signals (eg from the RDS data stream) are separated by a selection circuit 10, 11 and they are supplied to the storage 12 with the microprocessor 13. From the tuner 3, the data signals are also separated and they are also supplied to the storage 12 with the microprocessor 13. The tuner 2 can be tuned by manual or arbitrary activation. The tuner 3 is interrogated by the storage 12 or the microprocessor 13 over the line 14, corresponding to the stored alternate list.

Determination of the transmitter with the greatest field strength occurs in a coupling 15 by comparing the received signals from the tuner 2 and the tuner 3. If the tuner 2 is not set to the transmitter that can be received with the optimum field strength, the tuner 3 acquires this transmitter with the strongest field strength and its low frequency output signal NFB is applied across coupler 18 to low frequency amplifier 6 and speaker 20 7.

In this switching mode, the tuner 2 is interrogated over a line 20 from the microprocessor 12/13 corresponding to the frequencies stored in the alternate list.

The low frequency signals NFA and NFB are applied to a coupling 19 to compare the modulation of the two signals. In this modulation comparison coupling, the modulation content of the transmitter with the greatest field strength is compared with the modulation content of the transmitters selected from the alternative list. Conveniently, this comparison is made with the second most powerful transmitter in the list.

The comparison can be made by directly comparing the temporal course of the low frequency voltage.

I DK 175376 B1 I

I 20 I

gene or by comparison of the envelope curves I

H for the two low frequency signals. If the transmitter with the I

In the strongest field strength as a result of reflections I-

You show sudden modulation increases or modulus I

In 5 tions and low frequency cutoffs as a result I

of override, coupler 18 is automatically switched by I

H microprocessor 12/13 to the second most powerful transmitter, I

so that the distortions cannot be recognized by the user

In yer. If the two signals are identical, you remain

10 transmitter with the greatest field strength connected. Heref- I

However, the coupler 18 can be continuously operated by the just acting

sometimes receiver A, B is switched to the other receiver I

H B, A depending on microprocessor control. Alone I

You get a manual or other influence from the user

In the tuner 2 again first starter, and then you become

subject to the automatic RDS controlled mode of operation. IN

Claims (10)

21 DK 175376 B1 A method of utilizing on the receiving side digital information transmitted in a radio signal, e.g. AF-Code and / or PI-Code in RDS data signals, from which it is immediately apparent or can be deduced, at which alternative transmission frequencies the program signal received at the instantaneous reception frequency can also be received, wherein method a) to the instantaneous reception frequency alternate transmit frequencies, determined by utilization of the AF Code and / or the PI Code and / or equivalent codes; b) a receiver portion of the receiver is briefly tuned to an alternate frequency or successively to several alternate frequencies and the reception quality of each of these alternate frequencies and (c) as the optimum reception frequency, the frequency that provides the best possible reception quality is selected, characterized in that the reception quality is assessed by the fact that in the received digital information, e.g. in the received RDS data signal, bit errors detected serve as targets for error correction and / or for quality evaluation for program signal distortions to be detected, alone or in addition to the received field strength. A method according to claim 1, characterized in that the bit errors in the RDS data signal are used for the evaluation of program signal distortions in the sense that, in the case of sudden occurrence bit errors, interference resulting from multipath reception is caused. II or interference, I b) in the case of uniformly distributed errors, I have 5 disturbances resulting from noise, I c) the degree of all disturbances is derived from the II block error rate of the block-structured II RDS data signals, transmission frequency and bit rate errors detected for the instantaneous reception frequency, the following selection criteria are deduced: I d) If all frequencies investigated show essentially sudden occurrence or only uniformly distributed bit error, they are compared with I 15 considerations. to their block error rate with each other, whereby the frequency with the lowest block error rate I is selected for receiver tuning, I H- (e) if the frequencies studied exhibit different bit error distributions, first the frequencies that exhibit essentially only uniform II distributed bit error are first selected - possibly depending on the fact that a II determined maximum allowable block error rate does not II is exceeded at these frequencies - after which the preselected frequencies are compared with respect to their II 25 error rate, whereby the preselected frequency, which has the lowest block error rate, is selected for I receiver tuning. IN Method according to claim 1 or 2, ke η - characterized in that the digital information II 30 contains a series of individual links to the transmitters in a late IH chain, or to these transmitters II lists of alternative frequencies, in operation - II frequencies for the individual transmitters in the transmitter chain al- I 23 DK 175376 B1 time is placed at the beginning of the individual lists, where the digital information received is subject to an error correction and where, according to the incorrectly corrected digital information, addressing 5 of the alternate frequencies are performed on the basis of the transmitted operating frequency, if applicable, in or to each list. Method according to one of Claims 1 to 3, characterized in that the alternate frequencies transmitted in the digital information and, together with an associated transmitter operating frequency as frequency pairs, are addressed and optionally stored according to the immediately preceding or subsequent transmitter operating frequency. Method according to one of the claims 1-4, as a tuning aid for radio reception, wherein the digital information contains a series of separate transmitters belonging to each transmitter in a transmitter chain or optimized lists 20 of alternative frequencies, characterized in that by transfer of each list, as a result of digital blocks, each with two digital information per As a rule, rule (a) in the first block of each list transmits 25 information on the number of alternate frequencies in that list, as well as the operating frequency of the transmitter belonging to the list; and b) in the remaining blocks in each list. the operating frequency of the transmitter corresponding to the list 30 and the alternate frequency. Method according to claim 5, characterized in that the operating frequency transmitted on the receiving side in the blocks of each list is used for linking the alternate frequencies to the applicable list for a clear and disruptive operation. II Secure Addressing. IN Method according to one of claims 1-6, II 5, characterized in that the alternate frequencies received on all the frequency lists II are stored and / or used for tuning only the alternative II frequencies whose associated operating frequency corresponds to II. the radio receiver's instantaneous tuning frequency 10. IN A method according to any one of claims 1 to 7, characterized in that the alternative frequency, which at the receiving side momentarily offers the best possible reception, is tested as to whether II allows an acoustically acceptable reproduction and that II where, in case the tested alternative frequency only II allows an acoustically distorted reproduction, a second II alternative frequency is selected. IN Method according to one of claims 1 to 8, characterized in that the means for selecting I in another alternative frequency are manually adjustable. Method according to one of Claims 1 to 9, II, characterized in that the means for selecting II 25 are adjustable to another alternative frequency with an II signal which - possibly differently weighted - is derived from both the comparison of received field strengths, II and II. the comparison of the low-frequency distortions corresponding to the field forces. I I 30 I