DE10011259A1 - Radio receiver control parameters setting method determines actual geographic reception location for corresponding adjustment of control parameters - Google Patents

Abstract

The control parameters setting method determines the actual location of the radio receiver, e.g. via a navigation device and adjusts the control parameters of the radio receiver to match the actual location. When a spoken message or text display is provided by the radio receiver the language used can be selected to match the reception location.

Description

State of the art

The invention relates to a method for controlling Control parameters of a radio receiver, in particular Car radios, according to the genre of the independent Claim from.

From "Specifications of the Radio Data System for VHF / FM Broadcasting ", European Broadcasting Union, Brussels, March 1984 is known, in addition to a radio program on a Broadcast frequency inaudible digitally encoded To transmit additional information. These include for example a program identification PI), which is clearly a specific broadcast program is assigned, and which, among other things, a country code for Identification of the country in which the related program is broadcast contains. The above also include Information for example so-called lists of alternative Frequencies (Alternative Frequencies AF), such Specify broadcast frequencies over which the same Broadcasting program, such as via a currently received Broadcasting frequency is transmitted.  

The information mentioned enables automatic Re-tuning a radio receiver in the event of a deteriorating reception of a set Broadcast frequency to an alternative broadcast frequency that has better reception characteristics and the same program is transmitted as via the current one received radio frequency. As a benchmark for Reception quality of a radio frequency is known to come various parameters, such as the reception field strength, the Existence of multipath reception and adjacent channel interference and the data error rate of the over the broadcast frequency next to the Broadcasting program transmitted digital information signal, such as that in the RDS specification mentioned introduced RDS signal, in question.

In everyday operation, as well as in the context of more targeted Experiments have shown that today's radio receivers are fixed at given control parameters a changing behavior in Have a reaction to changing environmental conditions. So change the reception conditions of a currently received Broadcast frequency, for example, when driving through mountainous environment due to shadowing of the Broadcast signal through mountains or tunnels very quickly and frequently. In addition, for example Multipath reception as a result of reflections from the Broadcast signal and the associated interference in reproduced broadcast program signal observed. Similar Phenomena are also seen in areas with very high buildings, thus observed especially in large cities. From the point of view of The broadcaster therefore faces the transmitter landscape when passing through a changeable topography comparatively short-lived and subject to interference, so that Switching from a currently received radio frequency to an alternative frequency, as well as, for example  Search for alternative frequencies with the associated often time-consuming evaluations of the supposed program frequencies transmitted to alternative frequencies Identification of alternative frequencies and determination the reception qualities of the alternative frequencies as well as the associated interruptions in the reproduction of the currently received radio program for receivers with only a receiving part are required relatively often.

In contrast, there is a need for switching to alternative radio frequencies in the case of a flat Topography comparatively rare, namely mostly only when receiving a broadcast frequency currently being received due to the increasing distance of the receiver from the transmitter becomes weak. The need to switch to one alternative radio frequency is usually canceled in the long term so that there is enough scope to find a suitable one alternative radio frequency is available.

In today's radio receivers, especially those that are intended for mobile use often set compromise values for the control parameters, which on the one hand has sufficient responsiveness changing reception conditions, but also one stable and undisturbed reception with largely constant Enable reception conditions.

DE 39 38 457 A1 proposes to improve Adaptation of a radio receiver to different ones Locations the country code contained in the PI code evaluate, and control parameters depending on the Switch country codes.

Advantages of the invention

The inventive method with the features of independent claim, in which the control parameters of the radio receiver depending on a current one Receiver location can be set, where the receiver location is determined by means of a locating device on the other hand, advantageously enables a Adaptation of the control parameters to changing environmental and Conditions of receipt.

It is particularly advantageous that the Broadcast receivers do not rely on extensive experiments Determination of optimal, adapted to the present environment Control parameters, but these due to Locator information about the Topography surrounding recipient location can be set.

In particular, in contrast to the latter State of the art also within a country Control parameters optimal to the actual conditions be adjusted.

With the method according to the invention, in advantageously for speech or Text selected language with the language at the recipient location applicable official language automatically in accordance to be brought. Especially in the case of multilingual Countries, such as Switzerland, can use the language chosen according to the regional official language become. In this way you can, for example, on an otherwise Language setting required by the manufacturer to be dispensed with during the production process.

It is changing when using the radio receiver Locations, for example in the case of a car radio during  International trips, an advantage if after a first automatic location-dependent language selection automatic location-dependent language selection can be switched off, so that an originally chosen language for language and Text output is retained. This will be a user of the radio receiver to be reproduced or displayed Information in his familiar language Brought home knowledge.

An RDS strategy for evaluation can also be used alternative to a currently received radio frequency Broadcast frequencies or to switch to an alternative Broadcast frequency in the event of deteriorating Receive a currently received radio frequency in Dependence on environmental conditions such as the topography or development can be optimized depending on the location.

drawings

Embodiments of the invention are in the figures shown and are explained in more detail below.

Fig. 1 is a block diagram showing the essential part of the invention a broadcast receiver according to the invention, which is according to the invention connected to a locating device.

Description of the embodiments

An arrangement according to the invention for carrying out the method according to the invention is shown in FIG. 1 using the example of an RDS radio receiver connected to a locating device.

The radio receiver has a receiving antenna 2 , at which a mixture of frequency-modulated radio programs and, in addition, information signals carrying radio frequency signals is present. The radio frequency mixture present at the antenna 2 is fed to a receiving part 4 which, in a manner known per se, has the means required for receiving a radio frequency from the mixture of the radio frequencies and for demodulating it.

For this purpose, the receiving part 4 , as shown in FIG. 1A, has a mixer 41 , to which the antenna signal on the one hand and a mixed frequency on the other hand, which is dimensioned such that one of the radio frequencies contained in the antenna signal is in an intermediate frequency (IF) level , in the present case at approximately 10.7 MHz, for example, whereby a radio frequency is selected for reception. The mixing frequency is made available by a latching phase locked loop 42 (phase locked loop = PLL), to which an oscillator frequency of a reference oscillator (not shown) is fed, and which has a controllable frequency divider, the mixing frequency and. Being controlled by controlling the division ratio of the frequency divider by a frequency control signal so that the receiving frequency set on the receiving part 4 is predetermined. The broadcast frequency signal mixed down into the IF level is fed to an IF amplifier 43 for amplifying the IF signal for further processing. At a second output 431 of the IF amplifier 43 , a signal 432 indicating the received field strength of the received radio frequency can be removed. The amplified intermediate-frequency broadcast signal present at the output of the IF amplifier 43 is fed to a demodulator 44 for demodulating the intermediate-frequency frequency-modulated broadcast signal. At the output of the FM demodulator 44 , which also represents the output of the receiving part 4 , the modulation content of the received radio frequency can be removed.

At the output of the receiving part 4 , a so-called stereo multiplex signal (= MPX) can be removed, which modulates a stereo sum signal, namely a sum signal for the audio signals of the left and right stereo channels, and further modulates a 38 kHz stereo subcarrier Stereo difference signal and finally the digital radio data signal modulated onto a further subcarrier of the frequency 57 kHz in accordance with the RDS specification mentioned at the beginning.

The MPX signal is fed to a playback device 8 for playback of the received broadcast signal via a so-called muting circuit 6 for interrupting the playback of a received broadcast signal, which has the means required for playback of received broadcast signals in a manner known per se.

The muting circuit 6 shown in FIG. 1B is designed in the form of a controllable attenuator, or in the case of digitally available audio signals of a multiplier 61 , to which a variable attenuation factor, or in the case of the multiplier variable factor 65, is supplied by a mute curve controller 62 . The MPX signal fed to an input of the attenuator 61 or multiplier is evaluated in this according to the attenuation factor 65 . In the event that a signal indicating a playback interruption is applied to the control input 63 of the muting circuit 6 , the mute progression control generates a factor 65 which decreases from the value "1" to the value "0", preferably continuously, so that the MPX signal, in the preferred case a continuous decrease in the factor in the form of a smooth transition. Conversely, a signal at the control input 63 of the muting circuit indicating the end of a playback interruption causes the generation of a factor 65 increasing from the value "0" to the value "1" and thus the transmission of the MPX signal to the subsequent playback device.

As shown in FIG. 1C, the reproducing device comprises, in a manner known per se, an input filter 81 in the form of a low-pass filter for isolating the components of the audio signals to be reproduced, namely the stereo sum signal and the stereo difference signal, from the MPX signal Stereo decoder 82 for amplitude demodulation of the stereo subcarrier and for forming the audio signals to be reproduced for the left and right channels by superimposing the stereo sum and stereo difference signals, a sound influencing device 83 for frequency-selective amplification of the audio signals to be reproduced and, for example, for adjusting the volume , an at least two-channel low-frequency amplifier 84 for amplifying the possibly sound-influenced low-frequency audio signals to be reproduced and speakers 85 , 86 connected to this for reproducing the low-frequency audio signals. The stereo decoder has, in a manner known per se, a control input 821 , by means of which a suitable control signal can be used to control the extent of the stereo channel separation in response to reception disturbances of the currently received radio signal in the sense of a partial or complete cancellation of the stereo channel separation. It has been found that by reducing the stereo channel separation in the case of difficult reception conditions, the amount of audible interference in the reproduced audio signal can be significantly reduced. The stereo decoder also has an output 823 at which a signal 824 indicating adjacent channel and multipath reception interference , which is formed on account of the symmetry of the side bands of the stereo subcarrier, can be removed.

The MPX signal is also fed to a fault detector 10 , which has an input filter in the form of a high-pass filter, the cut-off frequency of which is above the useful signal components transmitted with the MPX signal, ie above 57 kHz, preferably at 60 kHz. The high-frequency component of the MPX signal taken from the input filter is fed to a level detection, the output signal 101 of which , which also forms the output of the fault detector 10 , is a measure of high-frequency faults in the MPX signal, for example as a result of ignition faults from the ignition system of a motor vehicle.

The stereo multiplex signal is also fed to an RDS decoder 12 for evaluating the RDS signal transmitted via a received radio frequency as part of the MPX signal, which in a manner known per se uses the necessary means for isolating the RDS signal from the MPX signal. Signal in the form of a 57 kHz bandpass, for synchronization with the RDS signal, for error detection and correction of faulty or disturbed received RDS signals and for the extraction of individual data from the RDS signal. A signal 122 indicating the data error rate of the received RDS signal can be seen from a first output 121 of the RDS decoder. At a second output 123 of the RDS decoder, the PI code 124 , an identifier which is provided in accordance with the RDS specification for uniquely identifying a radio program transmitted via a received radio frequency, can be removed.

The reception field strength of the currently received radio frequency indicating field strength signal 432 that the symmetry of the sidebands of the stereo subcarrier indicating balance signal 824, the high frequency disturbances in the MPX signal indicative of interference signal 101, the data error rate of the RDS signal indicating RDS error signal 122 and the PI code of the current reception frequency indicating signal 124 , hereinafter referred to briefly as PI code, are fed to a controller 14 which is explained in more detail below.

The controller 14 is used in a manner known per se to control the various functions of the radio receiver in accordance with a predetermined control program. Program-controlled radio receivers are known from various manufacturers, such as, for example, Blaupunkt-Werke GmbH, Hildesheim, so that the structure and function of the control program need not be discussed in more detail here.

The control also generates, for example, a tuning signal 141 for tuning the receiving part 4 to a specific radio frequency by specifying a divider ratio corresponding to a specific radio frequency for the divider of the PLL 42 of the receiving part 4 . Furthermore, the controller 14 also generates a mute signal, i.e. a playback interruption signal 142 , for actuating the muting circuit 6 via its control input 63 and thus for interrupting a current reproduction of a received radio signal, for example for masking out gross reception interference, for inaudible switching to an alternative to the current reception frequency Broadcast frequency of the same program content for checking their reception quality or for inaudible switching to a different broadcast frequency for checking their PI code in order to determine whether this other broadcast frequency is an alternative frequency, i.e. a broadcast frequency of the same program content.

The controller 14 is connected to a frequency memory 16 for radio frequencies, in which radio frequencies are stored, for example, sorted according to their PI code, ie their program content. The radio frequencies stored in the frequency memory 16 originate, for example, from the lists of alternative frequencies transmitted as part of the radio data signal via the currently set radio frequency. Alternatively, the radio frequencies can also be determined, for example, in the course of a station search over the radio frequency band, in which the PI code of each receivable radio frequency is evaluated. The radio frequencies of the same PI codes stored in the frequency memory 16 are available in the event of a deteriorating reception of the currently received radio frequency as alternative frequencies for replacement setting on the receiving part 4 instead of the current radio frequency.

Furthermore, the radio frequencies for each PI code are preferably stored sorted in the order of their reception quality. In the event of a deteriorating reception of the currently received radio frequency, this enables the controller 14 to quickly find the best alternative frequency to be received without first having to set all available alternative frequencies to check their reception quality. In the simplest case, the reception quality is defined via the reception field strength. Likewise, other parameters such as RDS error rate, symmetry of the sidebands of the stereo subcarrier and high-frequency interference components in the stereo multiplex signal can also be taken into account for assessing the reception quality. Furthermore, the further parameters mentioned can also be included in the quality assessment with different weightings and, moreover, depending on certain conditions, changing weighting.

The controller 14 is also connected to a parameter memory 18 in which parameter sets for the control program for controlling the radio receiver are stored.

The parameter sets stored in the parameter memory include different ones

• - Weightings for assessing reception quality a radio frequency used quantities, such as Reception field strength, RDS error rate, stereo subcarrier Sideband symmetry, the measure of high-frequency interference in the Stereo multiplex signal,
• - Time intervals in which tests are alternative Radio frequencies take place on reception quality,
• - Switching strategies for changing from a currently received radio frequency to an alternative frequency in the event of a deteriorating reception of the currently received radio frequency, namely either switching to an alternative frequency with prior checking of the PI code and the current reception quality, or without prior checking solely on the basis of the sorting in Frequency memory 16 ,
• - Languages to display, for example, as part of the Radio data signal transmitted, so-called radio text Messages (Radio Text RT), or to play back,  also as part of the radio data signal, in coded Form as part of the TMC (Traffic Message Channel) transmitted traffic information.

Furthermore, the controller 14 is connected to a location device 20 , in the case of a car radio preferably a location device for a motor vehicle, which can also be part of a vehicle navigation system known per se. The locating device comprises, in a manner known per se, a second controller 22 for controlling the various functions of the locating device in accordance with a second predetermined control program.

Program-controlled location devices are in one Numerous variants, for example from the Blaupunkt Werke GmbH, Hildesheim, available so that control programs for locating devices belong to the prior art and so that need not be explained in more detail.

In connection with the present invention, the control 22 of the locating device, i.e. the second control, has the task of using signals from sensors, such as wheel sensors 26 , on the basis of which a distance traveled can be calculated with a known wheel circumference, and on of angle sensors 28 , on the basis of which a direction of travel can be determined and finally, based on the position signals of a GPS receiver 24, to determine a current location of the vehicle or the radio receiver operated therein and this with a card 30 , for example stored on a CD-ROM, in the sense of a plausibility check to generate a compare reliable location information. This location information 21 and / or topography information derived from the location information with the aid of the map data is supplied to the controller 14 of the radio receiver.

In connection with the present invention, the control program of the controller 14 has a routine which assigns the control program for controlling the radio receiver in accordance with location information and / or topography information to at least one of the set of parameter sets stored in the parameter memory 18 and thus the control program as a function of the Location information and / or topography information influenced.

The arrangement according to the invention described above is Basis for the invention described below Method.

In a first embodiment of the invention provided that for voice output, for example by means of the radio data system in encrypted form transmitted traffic information (TMC), or that for Text ads on a display unit of the Radio receiver, for example by means of the radio Data system broadcast radio text messages (RT) or the station name of the currently selected radio station (PS), selected language with the one valid at the recipient location Official language or alternatively one predominant spoken dialect is brought into line.

If, for example, a radio receiver according to the invention in the form of a car radio is installed in a motor vehicle and the car radio is put into operation at the customer's home location for the first time after delivery of the vehicle to the customer, the second controller 22 of the locating device 20 determines from the data from the sensors 24 to 28 the current vehicle location with the aid of the map information 30 and transmits this location information to the controller 14 of the car radio. Depending on the location information, this reads from the parameter memory 18 a parameter set, in the present case the official language belonging to the recipient location, for subsequent output, be it voice output, for example, of traffic information transmitted by means of the RDS-TMC system or the display of information using the RDS - Systems broadcast radio text information (RT) or station name (PS) is used.

If, for example, the vehicle is delivered to Bern, Switzerland, the locating device determines a point within the city of Bern as the current location when the radio receiver and the locating device are put into operation. A language parameter set belonging to the Bern location is selected in the parameter memory 18 , so that the German language is selected for subsequent outputs. If, on the other hand, the vehicle is delivered to Geneva, i.e. the French-speaking part or to Chiasso, the Italian-speaking part of Switzerland, the French or Italian language will be selected after subsequent commissioning of the radio receiver and the locating device for subsequent issues, depending on the receiver location determined.

It can also be provided that instead of preferred official language preferred at the recipient location spoken language or a dialect for speech output is chosen. For example, in parts of Switzerland instead of the official official language German, the Romansh language chosen for the speech output become.

In a further development of this embodiment provided that the last language set for  further speech outputs can be saved and the automatic location-dependent language selection can be switched off. So after an automatic location-dependent language selection information to be displayed even when traveling abroad, where one from the home location of the radio receiver different language is valid, the driver in the reproduced the familiar language of his home location become.

In a second embodiment of the invention provided that to assess the reception quality a radio frequency used quantities, such as Reception field strength, RDS error rate, stereo subcarrier Sideband symmetry and the measure of high-frequency interference in the Stereo multiplex signal depending on the Recipient location are taken into account.

For example, the phenomenon of Multipath reception by reflecting a received one Radio frequency on mountain ranges or high buildings and Reception not only that from the radio station broadcast, but also reflected radio signals. Multi-way reception affects both the quality of a Playback of an audio signal received via radio, as also on the error rate of the received over Broadcast frequency transmitted radio data signal.

In contrast, multi-path reception plays on flat terrain practically no role.

Therefore, in the second exemplary embodiment of the invention, the variables relevant for evaluating the reception quality of a received radio frequency are carried out as a function of the current receiver location or information derived therefrom about the topology of the surroundings of the receiver location. If, for example, after the location of the receiver 20 has been determined by the locating device 20 and the topology of the location of the receiver has been determined on the basis of the stored map information, that the receiver is located in a mountainous area or in a high-rise area, a parameter set is selected from the parameter memory 18 of the radio receiver , in which the relevant parameters for determining multipath reception flow with a high weight in the assessment of the reception quality of a received radio frequency. If, on the other hand, a receiver location is found in a practically flat environment, for example the North German Plain outside of larger cities, i.e. far away from higher buildings, a multipath reception situation is unlikely to occur. For this reason, the parameters that are decisive for the determination of multi-path reception for the assessment of the reception quality of a radio frequency in accordance with the specifications of a correspondingly selected parameter set are considered less strongly.

Because of the situation described, namely in places poor reception conditions in the mountains or in the High buildings due to shadows or Reflections, the transmitter density is higher in such an environment than in a flat environment to get an acceptable reception guarantee. Thus there is a lack of reception field strength due to the distance from the transmitter location in the mountains or the surrounding area less frequently than in level environment where the transmitter density is generally lower is selected. Therefore, depending on the station location the reception field strength for assessing the reception quality at a location of the recipient in level surroundings considered relatively more than one Receiver location in the mountains or in the vicinity of high  Development is the case, as in this case, as already mentioned, for example also multi-way reception in the Includes quality assessment.

According to a third embodiment of the invention also the parameters for those realized in the radio receiver RDS strategies depending on the recipient location chosen.

For example, in the mountains more common AF PI tests required than in the level. Under AF-PI Tests is a short trial switching of the Receiver from the currently received radio frequency an alternative frequency (AF) for the purpose of checking the over the alternative broadcast frequency broadcast Program identifier (PI), i.e. to identify the via the Alternative frequency transmitted program, with subsequent switch back to the original set radio frequency understood. Because in the mountains Density of the transmitter locations through so-called filling transmitters for Valleys and shadows are usually higher than in the Plain and also, for example, on mountain tops or in valleys Under certain circumstances, stations from a neighboring country can also be received can not be guaranteed that an im Receiver stored as an alternative frequency Broadcast frequency actually the same program as transmits the currently set radio frequency. Therefore is before a vote on an alleged one Alternative frequency, for example to improve reception if the reception quality of the currently received deteriorates Broadcast frequency, the program identifier of this supposed Check alternative frequency.

In contrast, the transmitter density is in the lowlands comparatively small, in addition to each other  adjacent areas from neighboring transmitters different program chains are not the same Broadcast frequencies used. PI exams are here not before every switchover to an alternative frequency imperative.

Accordingly, when determining the recipient location in Mountains before switching to an alternative Broadcast frequency, which based on its last rating a better reception than a currently set one Broadcast frequency can be expected, their PI code Corresponds to that of the originally set Receiving frequency checked. This review is due the low data rate of the RDS signal, its Susceptibility to interference and the need for synchronization of the receiver to the RDS signal comparatively time consuming and therefore requires audible interruptions of the Playback of a received broadcast signal. Therefore at AF switching in the lowlands on PI tests rather waived.

In a fourth embodiment of the invention provided that the card base also information about Contains transmitter locations and / or information about them, which stations at certain locations, for example particularly well in certain valleys of a mountain range are received. In this case, due to Card base information for a specific Broadcasting program due to the existing in the card base Information on the radio receiver is the best for each receiving radio frequency without prior elaborate Alternative frequency tests and evaluations depending on location can be set. Alternative frequency tests can in addition to verifying the card information with regard to the radio frequencies.  

It is within the scope of the present invention that the above embodiments with each other can be combined. It also lies in the area of the invention, not just a country or topography-dependent parameter setting. Rather, regional ones can also be used Peculiarities that only apply to a very specific one Applicant location apply, are taken into account. For example, a spatial selection of received traffic information possible that only relevant for the recipient location Traffic information can be played.

Claims (5)

1. Method for controlling control parameters of a radio receiver,
characterized in that the control parameters are set depending on a current recipient location,
and that the receiver location is determined by means of a locating device. 2. The method according to claim 1, characterized in that for speech output or text ads the on Recipient location valid, or in the case of multiple languages one of the official languages valid at the recipient location or a preferred spoken language at the recipient site is chosen. 3. The method according to claim 2, characterized in that the automatic location-dependent language selection can be switched off so that a last selected language is retained. 4. The method according to any one of the preceding claims, characterized characterized that the control parameters the Consideration or weighting of measured variables for Quality assessment of a radio frequency include. 5. The method according to any one of the preceding claims, characterized characterized that the control parameters are a strategy for Evaluation of radio frequencies and / or for switching from a current to an alternative broadcasting frequency same program content.