EP3228031A1

EP3228031A1 - Method and device for receiving a broadcast signal

Info

Publication number: EP3228031A1
Application number: EP15775462.3A
Authority: EP
Inventors: Manh-Thang Tran; Marcus Risse
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2014-12-05
Filing date: 2015-10-09
Publication date: 2017-10-11
Anticipated expiration: 2035-10-09
Also published as: WO2016087099A1; CN107005321A; CN107005321B; DE102014225043A1; EP3228031B1

Abstract

The invention relates to a method for receiving a broadcast signal. According to the invention, in a first step, reference information (108) relative to a signal quality of the broadcast signal at a reference point in time is read in. In an additional step, signal information (110) relative to a signal quality of the broadcast signal at a current point in time is received. In a third step, the signal quality detected at the current point in time is checked, using the signal information (110) and the reference information (108), in order to measure the reproduction quality of the broadcast signal.

Description

Description title

Method and apparatus for receiving a broadcast signal prior art

The present invention relates to a method for receiving a broadcast signal, to a corresponding device and to a

corresponding computer program.

AM broadcast receivers that use the amplitude modulation as a modulation type, usually have a search function to set from a set reception frequency to the next receivable station and play. In this case, the reception frequency can be increased or decreased by a fixed frequency step. On the new reception frequency can now be checked, for example, whether a

Receive field strength is greater than a threshold value and if quality information indicating further disturbances are smaller than a threshold value. If all criteria are met, the search can be ended, with the current frequency being used for playback.

Disclosure of the invention

Against this background, with the approach presented here, a method for receiving a broadcast signal, furthermore a device which uses this method, and finally a corresponding computer program according to the main claims are presented. Advantageous embodiments emerge from the respective subclaims and the following description. The approach proposed here provides a method for receiving a broadcast signal, the method comprising the steps of:

Reading reference information about a signal quality of the broadcast signal detected at a reference time;

Receiving signal information about a signal quality of the broadcast signal detected at a current time; and

Checking the signal quality detected at the present time using the signal information and the reference information to determine a reproduction quality of the broadcasting signal.

A broadcast signal can be understood to mean an amplitude-modulated signal, such as a long, medium or shortwave signal of a radio transmitter. A signal quality of the broadcast signal, for example, by a

Reception field strength of the broadcast signal, a disturbance of the broadcast signal or a reception field strength of neighboring signals of the broadcast signal to be characterized. A reference time can be understood to mean a time before the current time. For example, the step of reading in a predetermined rhythm may be repeatedly executed to read in a plurality of reference information, each reference information representing a signal quality of the broadcasting signal detected at a different reference timing. The reference information, for example, in a suitable memory, also called landscape memory, be maintained during a predetermined period of time and read from there in the step of reading. The reading and receiving steps can be performed simultaneously or sequentially in any order. The signal quality of the broadcast signal detected at the present time can be used, for example, in the step of checking

different threshold comparisons. The threshold values used in this case can be chosen so that the broadcast signal has a sufficiently high quality of reproduction in a successful test. The approach presented here is based on the knowledge that a signal quality of a receivable broadcast signal can be tested as a function of an earlier signal quality of the broadcast signal. As a result, fluctuations in the signal quality due to reception time can be detected and taken into account during the examination of the broadcasting signal. For example, by means of such a test, a search function of a radio receiver can be controlled such that at different reception times of the radio receiver

Broadcasting signal a consistently good reproduction quality is guaranteed. In particular, the reception of AM stations can be heavily dependent on the time of day. While daytime attenuation in the area of long, medium and short wave bands means that relatively few transmitters can be received during the day, significantly more transmitters can be received during twilight and at night. However, many of these transmitters can be affected by strong field strength loss, English fading, adjacent channel interference or other electromagnetic

Interferences are disturbed.

These daytime-dependent signal impairments can now be taken into account in a station search by responding not only to currently determined signal quality parameters such as a reception field strength or quality values indicating further disturbances, but additionally in one

Landscape memory stored signal information can be used to determine a respective reception quality of the transmitter. The

Signal information, for example, in a separate

Signal processing path next to a playback path are determined.

In this way, the search can be designed so that at any time of day stations with a sufficiently good reception quality are played. The method may be provided with a step of determining a check threshold using the reference information. The signal quality detected at the present time can be compared with the test threshold value. In this case, the signal quality detected at the present time can be checked in the step of checking if it exceeds the test threshold value. A test threshold value can be understood as a reception field strength which the broadcast signal must at least have to be tested in the testing step. For example, the check threshold may vary depending on a number of receivable broadcast signals that exceed a certain field strength threshold and a particular one

Fault threshold below, be predetermined. With the help of

Check threshold value can be prevented that broadcast signals that have a low signal quality from the outset and thus for a

Playback are not suitable for further examination. This can increase the efficiency of the process.

In this case, it is advantageous if, in the reading-in step, at least one additional reference information is read in via a signal quality of an additional broadcast signal detected at the reference time or at an additional reference time. Similarly, in the step of determining, the check threshold may be further determined using the additional

Reference information can be determined. An additional broadcast signal can be understood to mean a broadcast channel deviating from the broadcast signal. The signal quality of the additional broadcast signal can be either at the reference time or at a different additional

Be recorded reference time. By means of the additional reference information, it is possible, for example, to determine a general quality of broadcast reception over a frequency range comprising a plurality of broadcast signals. In this case, the test threshold value can be determined as a function of the general quality of the radio reception. For example, a low test threshold can be selected, if only a few good receivable

Broadcast signals are present, or a high test threshold value can be selected, if many well receivable broadcast signals are present.

The reference information can be in the step of reading a for

Reference time recorded received field strength of the broadcast signal

represent. Additionally or alternatively, the reference information may be a detected at the reference time disturbance of the broadcast signal or a for

Reference time detected detected field strength of at least one adjacent signal of the broadcast signal. Analogous to the reference information, the signal information in the step of receiving one at the current time detected reception field strength of the broadcast signal or, additionally or alternatively, detected at the current time disturbance of the broadcast signal or detected at the current time receiving field strength of the

Represent the neighboring signal. A receive field strength can be understood as a measured value of a field strength with which the broadcast signal from a radio receiver, such as a long, medium or

Shortwave receiver, is received. A disturbance can be a measured value of the signal quality which represents a deterioration of the signal quality

Broadcasting signal or a signal interacting with the broadcast signal are understood. A neighboring signal may be understood to mean a signal, such as an adjacent radio transmitter, whose frequency range is adjacent to or at least close to a frequency range of the broadcasting signal. By means of such reference information, the signal quality of the broadcast signal can be determined comprehensively and with great accuracy.

It is also advantageous if, in the step of reading in, at least one further reference information is read in via a signal quality of the broadcast signal detected at a further reference time. In the step of checking, the signal quality detected at the present time can also be checked using the further reference information. By virtue of the fact that the signal quality detected at the present time can be compared in the step of checking with at least two older signal qualities detected at a different point in time, it is possible, for example, to reliably determine a field strength decrease of the broadcast signal.

According to a further embodiment, in the step of reading in, the further reference information may represent a received field strength of the neighboring signal detected at the further reference time. In the step of testing, a field strength average from the detected at the reference time

Receiving field strength of the neighboring signal and the other

Reference time detected reception field strength of the neighboring signal are formed. In this case, a difference between the field intensity mean value and the received field strength detected at the present time can be determined and compared with a predetermined difference value. Under a Field strength mean can be understood, for example, an arithmetic, geometric or harmonic mean. This can be a one

Reception quality of the broadcast signal impairing neighboring signal can be detected.

It is also advantageous if, in the step of checking, a deviation between the reception field strength detected at the reference time and the reception field strength detected at the current time is determined. The deviation can be compared with a predetermined deviation value. To determine the deviation, for example, a variation of the respective reception strengths can be determined. By comparing the deviation with the deviation value, a field strength variation of the broadcasting signal can be detected.

Furthermore, in the step of testing, a mean interference level from the to

Reference time detected fault and the detected at the current time disturbance is formed. The perturbation mean can be compared to a given perturbation value. By using such averaged disturbance value, the accuracy of the test of the

Broadcast signal to be increased.

Depending on the embodiment, in the step of checking, the difference value, the deviation value or the disturbance value may be determined as a function of a

Speed of a vehicle receiving the broadcast signal

be predetermined. For example, at high speed the

Deviation value and the disturbance value be higher than at low speed. As a result, a consistently good playback of the broadcast signal can be ensured even at different speeds.

The method may be provided with a step of reproducing the broadcast signal. The step of reproducing may be performed if, in the step of checking, the field strength average is greater than the difference detected at the current time at most

Reception field strength is or, additionally or alternatively, the deviation is smaller than the deviation value or, additionally or alternatively, the Interference mean value is less than the disturbance value. This can ensure that the broadcast signal is only reproduced if a sufficiently good reproduction quality has resulted in the step of checking. The approach described here also provides an apparatus for receiving a broadcast signal, the apparatus comprising the following features: a read-in unit for reading in reference information about a signal quality of the broadcast signal detected at a reference time; a receiving unit for receiving signal information about a signal quality of the broadcast signal detected at a current time; and a check unit for checking the signal quality detected at the present time using the signal information and the reference information by one

To determine the playback quality of the broadcast signal.

In the present case, a device can be understood as meaning an electrical device which processes sensor signals and outputs control and / or data signals in dependence thereon. The device may have an interface, which may be formed in hardware and / or software. In the case of a hardware-based embodiment, the interfaces can be part of a so-called system ASIC, for example, which contains a wide variety of functions of the device. However, it is also possible that the interfaces are their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules. Of advantage is also a computer program product or computer program with

Program code, which may be stored on a machine-readable medium or storage medium, such as a semiconductor memory, a hard disk memory or an optical memory, and for carrying out, implementing and / or controlling the steps of the method according to one of the above

described embodiments is used, in particular when the Program product or program is executed on a computer or a device.

The approach presented here will be described below with reference to the attached

Illustrated drawings by way of example. Show it:

Fig. 1 is a block diagram of a device according to an embodiment of the present invention;

2 shows a schematic representation of a receiving system with a device according to an embodiment of the present invention; and

3 is a flowchart of a method according to a

Embodiment of the present invention.

In the following description of favorable embodiments of the present invention are for the in the various figures

represented and similar elements acting the same or similar

Reference numeral used, wherein a repeated description of these elements is omitted.

Fig. 1 shows a block diagram of a device 100 according to a

Embodiment of the present invention. The apparatus 100 for receiving a broadcast signal comprises a read-in unit 102, a receiving unit 104 and a test unit 106. The read-in unit 102 is designed to transmit a reference information 108 via a to a

Reference time recorded signal quality of the broadcast signal. The receiving unit 104 is designed to receive signal information 110 via a signal quality of the broadcast signal detected at a current point in time. The test unit 106 is configured to receive the information 108, 110 and, using the information 108, 110, to check the signal quality detected at the present time. For example, the test unit 106 is configured to detect the current time

Check signal quality by means of different threshold comparison. Depending on the embodiment, the read-in unit 102 and the

Receiving unit 104 via separate interfaces or a common interface with a suitable receiver for receiving the

Be connected to the broadcast signal. According to one embodiment, the read-in unit 102 or the receiving unit 104 is designed to accommodate the

Reference information 108 and the signal information 110 directly from the

Receive receiver. Alternatively, the read-in unit 102 and the

Receiving unit 104 is formed to receive each of the broadcast signal from the

Receive receiver and using the broadcast signal to generate the reference information 108 and the signal information 110 itself.

According to the embodiment shown in FIG. 1, the device 100 has a coupled to the receiving unit 104 and the test unit 106

Detection unit 112, which is designed to use the reference information 108 to determine a test threshold value 114 and to send this to the test unit 106. In addition, the detection work 112 in FIG. 1 is coupled to the read-in unit 102 to supply the signal information 108

and to determine the check threshold 114 further using the signal information 108. The test unit 106 is designed to detect the signal quality of the broadcast signal detected at the present time,

hereafter briefly called current signal quality, using the

Check threshold 114 to undergo an incoming inspection. If this input check shows that the current signal quality is above the

Test threshold value 114, the current signal quality is checked by further test criteria by the test unit 106, as described in more detail below. If, on the other hand, the current signal quality lies below the test threshold value 114, then the test of the broadcast signal is interrupted by the test unit 106. The test unit 106 is configured to respond in response to a successful

Examination of the current signal quality using the further test criteria, ie to produce a playback signal 116 with an expected good reproduction quality of the broadcast signal. A playback device coupled to the device 100 may be configured to encode the playback signal 116 receive and reproduce the broadcast signal using the reproduction signal 116.

Depending on the embodiment, the read-in unit 102 may be configured to transmit at least one further reference information 118 via one to another

Reference time detected signal quality of the broadcast signal or at least one additional reference information 120 detected at a reference time or at a different time from the reference time

Signal quality of an additional broadcast signal to read. Here, the further reference time and the additional reference time analogous to

Reference time each represent a time preceding the current time. The determination unit 112 may be configured to receive the additional reference information 120 from the read-in unit 102 and to further use the additional threshold value

Reference information 120 to determine. The test unit 106 may be configured to receive the further reference information 118 from the read-in unit 102 and to further check the current signal quality of the broadcast signal using the further reference information 118. Fig. 2 shows a schematic representation of a receiving system 200 with a

Device 100 according to an embodiment of the present invention. The device 100 is, for example, a device as described with reference to FIG. 1. The receiving system 100 may be part of a radio receiver. In particular, the radio receiver may be suitable for use in a vehicle.

According to the embodiment shown in FIG

Receiving system 200, a first signal processing path 202, too

Called a reproduction path, and a second signal processing path 204.

Optionally, however, the receiving system 200 may also be used with more than two

Be implemented signal processing paths. The signal processing paths 202, 204 are configured to process amplitude modulated signals.

For this purpose, the reproduction path 202 has a high-frequency processing unit 206, which is designed to supply a high-frequency signal as a broadcast signal 208 to process. In the high-frequency processing unit 206, the

For example, broadcast signal 208 is filtered, mixed and amplified.

Furthermore, the reproduction path 202 comprises a signal processing block serving as a demodulation unit 210, which is connected to the

High frequency processing unit 206 is coupled to the

demodulate amplitude modulated broadcast signal 208.

Another signal processing block of the playback path 202 functions as an information providing unit 212 which is configured to provide information about a channel field strength, also called reception field strength, as well as other signal quality indicative values such as a

To generate adjacent channel detector value or a value obtained from a differentiated phase signal.

Analogous to the reproduction path 202, the second signal processing path 204 comprises a further high-frequency processing unit 214, another one

Demodulation unit 216 and another information providing unit 218th

The apparatus 100 according to this exemplary embodiment is designed to provide control software for controlling the signal processing paths 202, 204

perform. For this purpose, the device 100 reads in the

Information providing units 212, 218 determined values. These values may include the reference information 108, 118, 120 as well as the signal information

110 include. Further, the device 100 controls the

High frequency processing units 206, 214 to various

Set reception frequencies. The device 100 can be realized with a so-called landscape memory, in which for each AM receive frequency a plurality of entries are stored via a respective receive field strength and respective fault information together with a time information. For example, the

Landscape memory configured to store ten different entries for each AM receive frequency. Are for a particular AM Receiving frequency already ten entries available, then the oldest value is overwritten to enter a new value.

The device 100 controls the second signal processing path 204 to pass through the AM receive frequencies supported by the radio receiver in a fixed timing scheme, or when not required for other tasks. The reception field strength and the interference information for each set AM receive frequency are entered together with a time stamp in the landscape memory.

The apparatus 100 reads the landscape memory at a fixed rhythm. In this case, the device 100 can be designed to determine the test threshold value for an AM search depending on a number of those transmitters which exceed a certain field strength threshold and fall below a certain interference threshold. If the landscape memory contains only a few receivable stations, the test threshold value will be set correspondingly low. If, however, many stations are receivable well, then the

Test threshold value set correspondingly high. In one embodiment, the device 100 is configured to promptly activate the second signal processing path 204 in response to starting an AM search by a user of the broadcast receiver. Thereby, a search of a current receiving frequency of the reproducing path 202, also called a playback receiving or reproducing signal path, is activated in a direction defined by the user. The determined

Values for the reception field strength and the fault information are again entered together with a time stamp in the landscape memory.

After a short delay, the device 100 now also starts an AM search in the reproduction path 202. At each reception frequency, a current value of the reception field strength and current quality values, for example a disturbance of the reception frequency or a reception field strength of adjacent reception frequencies, are determined. If the received field strength is below the determined check threshold value, which can also be referred to as the search threshold, the device 100 sets the next receive frequency. The test is now carried out again. If the reception field strength of the next reception frequency lies above the determined check threshold value, the device 100 checks all entries of the landscape memory for the set reception frequency as well as the entries for the respectively adjacent channels. Only those entries are considered, the one

given age of for example 10, 15 or 30 minutes not

exceed.

Depending on the embodiment, the device 100 now checks one or more of the following criteria.

First, the device 100 checks whether a variation of the received field strengths stored in the landscape memory, including the currently determined reception field strength, is less than a predetermined deviation threshold value.

Second, the device 100 checks whether a mean interference level in the

Landscape memory stored fault information including the currently determined fault information smaller than a predetermined

Fault threshold is.

Third, device 100 checks to see if a field strength average of the

Landscape memory stored reception field strengths of the adjacent channels at most by a predetermined amount greater than the current

Receive field strength is.

Is the radio receiver a mobile one?

Broadcast receiver in a vehicle, the device 100 may be configured to control the respective threshold values for the above-mentioned criteria in dependence on a driving speed of the vehicle. If the vehicle is stationary, the thresholds for the field strength variation and the disturbance information can be set low. If the vehicle moves, the threshold values can be increased accordingly.

The first criterion determines whether a station with a high field strength fluctuation is received at the current reception frequency. Is this the Case, the current reception frequency is not reproduced. The second criterion evaluates averaged fault information, which allows a more accurate image than a single measurement. Via the third criterion, stations with a very strong adjacent channel are suppressed, since reception problems due to the adjacent channel are to be expected here.

When all of the above criteria are met, the apparatus 100 stops the AM search on the reproduction path 202 and outputs the set one

Receive frequency free for playback.

FIG. 3 shows a flowchart of a method 300 according to FIG

Embodiment of the present invention. The method 300 for

Receiving a broadcast signal, for example, by a device, as described with reference to Figures 1 and 2, are performed.

According to an exemplary embodiment, the method 300 can be used for

Search optimization are performed. This is done in a first

Method step 302 first read in reference information about a detected at a reference time signal quality of the broadcast signal. In a further method step 304, signal information about a signal quality of the broadcast signal detected at a current time is received. Steps 302, 304 may be simultaneous or arbitrary

Order to be performed. Finally, in a step 306, the signal quality detected at the present time is checked by using the signal information under reference information to determine a reproduction quality of the broadcast signal.

Depending on the embodiment, in steps 302, 304 a

Reception field strength of the broadcast signal, a disturbance of the broadcast signal or a reception field strength of at least one adjacent signal of the

Broadcast signal are read as information about a signal quality of the broadcast signal.

The embodiments described and shown in the figures are chosen only by way of example. Different embodiments may be combined together or in relation to individual features. Also can an embodiment be supplemented by features of another embodiment. Furthermore, the method steps presented here can be repeated as well as executed in a sequence other than that described.

If an exemplary embodiment comprises an "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

Claims

claims

A method (300) for receiving a broadcast signal (208), the method (300) comprising the steps of:

Reading (302) reference information (108) about a signal quality of the broadcasting signal (208) detected at a reference time;

Receiving (304) signal information (110) about a signal quality of the broadcast signal (208) detected at a current time; and

Checking (306) the signal quality detected at the present time using the signal information (110) and the reference information (108) to determine a reproduction quality of the broadcast signal (208).

The method (300) according to claim 1, further comprising the step of determining a check threshold using the reference information (108), wherein in the step of checking (306) the signal quality detected at the present time is checked if the signal quality detected at the present time is the Check threshold exceeds.

3. Method (300) according to claim 2, wherein in the step of reading (302) at least one additional reference information (120) is read in via a signal quality of an additional broadcast signal detected at the reference time or at an additional reference time, wherein in the step of determining the check threshold value is further determined using the additional reference information (120). Method (300) according to one of the preceding claims, in which, in the step of reading in (302), the reference information (108) has a reception field strength of the

Broadcast signal (208) and / or interference of the broadcast signal (208) and / or received field strength of at least one adjacent signal of the broadcast signal (208), wherein in the step of receiving (304) the signal information (110) detected at the current time receiving field strength of the broadcast signal (208 ) and / or interference of the broadcast signal (208) and / or reception field strength of the

Neighbor signal represents.

Method (300) according to one of the preceding claims, wherein in the step of reading (302) at least one further

Reference information (118) about one to another

Reference signal recorded signal quality of the broadcast signal (208) is read, wherein in the step of checking (306), the signal quality detected at the current time is further checked using the further reference information (118).

Method (300) according to claim 4 and 5, wherein in the step of reading (302) the further reference information (118) detects a received field strength of the

In the step of testing (306), a field strength average from the detected at the reference time point

Receiving field strength of the neighboring signal and the other

Reference time detected field strength of the adjacent signal is formed, wherein a difference between the field strength mean and the detected at the current time receiving field strength is determined and compared with a predetermined difference value.

A method (300) according to claim 4 or 6, wherein in the step of checking (306), a deviation between the received field strength detected at the reference time and the received field strength detected at the current time is determined, the deviation being compared with a predetermined deviation value. A method (300) according to any one of claims 4, 6 or 7, wherein in the step of checking (306) a mean interference level from that of

Reference time detected disturbance and the detected at the current time disturbance is formed, wherein the disturbance mean value is compared with a predetermined disturbance value.

Method (300) according to one of Claims 6 to 8, in which, in the step of checking (306), the difference value and / or the deviation value and / or the interference value are predetermined as a function of a speed of a vehicle receiving the broadcast signal (208).

The method (300) according to any one of claims 6 to 9, comprising the step of reproducing the broadcast signal (208) if, in the step of checking (306), the field strength average is greater than the received field strength and / or the deviation detected by the difference value at most greater than the current time is less than the deviation value and / or the mean interference value is less than the disturbance value.

Apparatus (100) for receiving a broadcast signal (208), the apparatus (100) comprising: a read-in unit (102) for reading reference information (108) about a signal quality of the broadcast signal (208) detected at a reference time; a receiving unit (104) for receiving signal information (110) about a signal quality of the broadcasting signal (208) detected at a current time; and a check unit (106) for checking the signal quality detected at the present time using the signal information (110) and the reference information (108) to obtain a reproduction quality of the

Broadcast signal (208) to determine. A computer program adapted to perform all the steps of a method (300) according to any one of claims 1 to 10

A machine-readable storage medium having a computer program stored thereon according to claim 12.