Abstract:
A radio apparatus ( 95 ), particularly for mobile radio, which makes it possible to adjust the signal reception in a predeterminably optimized way is proposed. The radio apparatus ( 95 ) includes a receiver part ( 1 ) and an evaluation unit ( 5 ), which controls the sensitivity and/or the signal-to-noise ratio of the receiver part ( 1 ) as a function of a predeterminable signal reception quality and the actual signal reception. In the event of defective signal reception, the evaluation unit ( 5 ) increases the sensitivity and/or the signal-to-noise ratio of the receiver part ( 1 ), and when signal reception is error-free for a predeterminable time it reduces the sensitivity and/or the signal-to-noise ratio of the receiver part ( 1 ).

Description:
BACKGROUND OF THE INVENTION 
   The invention is based on a radio apparatus provided with a receiver part. 
   Radio apparatuses that are provided with a receiver part for signal reception from radio stations are already known. 
   SUMMARY OF THE INVENTION 
   The radio apparatus of the invention has the advantage over the prior art that the quality of the actual signal reception can be adapted to a signal reception quality that can for instance be predetermined by the user. In this way, the reception quality of the radio apparatus can be adjusted individually as needed. 
   It is especially advantageous that in the event of defective signal reception, the evaluation unit increases the sensitivity and/or signal-to-noise ratio, particularly in the event of neighboring channel disturbance or intermodulation, of the receiver part, and in the event of error-free signal reception for a predetermined time lowers the sensitivity and/or signal-to-noise ratio of the receiver part. In this way, especially in good reception conditions, energy can be saved, so that the service life of a battery in the radio apparatus is increased. 
   It is also advantageous to use at least one add-on reception amplifier, which the evaluation unit adds in the event of defective signal reception and bypasses in the event of error-free signal reception. This provides an especially simple opportunity of varying the sensitivity of the receiver part, which particularly in the case of error-free signal reception leads to a considerable electrical saving. 
   It is also advantageous that the receiver part has at least one mixer, and that the evaluation unit, in the event of defective signal reception, increases the power supply of the at least one mixer to a first pre-determined value and in the event of error-free signal reception reduces it to a second predetermined value. In this way an especially simple possibility for varying the signal-to-noise ratio and in particular the intermodulation performance of the receiver part is provided, in which the power consumption can be reduced considerably, especially for error-free signal reception. 
   It is also advantageous that the receiver part includes at least one first filter configuration and one second filter configuration, and that the evaluation unit switches over to the first filter configuration in the event of defective signal reception and to the second filter configuration in the event of error-free signal reception. In this way, depending on whether neighboring channel filtration is especially important or interference in the useful channel has to be blanked out, it is possible to select that filter configuration which is more suitable for a given case, so that as a result, it is easy to optimize the quality of the signal reception. 
   It is also advantageous that an operating mode is provided in which the evaluation unit increases the sensitivity and/or the signal-to-noise ratio of the receiver part to a maximum value. In this way, a switchover to maximum sensitivity and/or signal-to-noise ratio of the receiver part can be made at any time, if power consumption is not crucial, such as for testing purposes. 
   It is also advantageous that and that the operating mode can be established as a function of a chip card detected in the insertion slot by the card reader. In this way, for an equipment test, the performance of the receiver part of the radio apparatus can be checked with the aid of the chip card. At the same time, the chip card can perform the function of access authorization for testing purposes. 
   A further advantage is that the operating mode can be established at the radio apparatus, preferably by a key on the radio apparatus. This is an especially simple provision for adjusting the maximum performance of the receiver part of the radio apparatus. 
   Still another advantage is that the operating mode can be established at the radio apparatus as a function of a request by a base station, preferably for sending back a signal sent previously to the radio apparatus. In this way, the receiver part of the radio apparatus is adjusted automatically, for instance for testing purposes initiated by the base station, to the best possible reception quality. 
   It is furthermore advantageous that the operating mode can be established upon detection of an external power supply, in particular via a power supply adapter, and/or of a connected external antenna. In this case, power saving provisions in the radio apparatus can be dispensed with in favor of improved signal reception, since an external power supply is available, or above all if a connected external antenna is detected, it can be concluded that the radio apparatus is being used in a motor vehicle, so that it can be expected that the radio cells involved will change faster than when the radio apparatus is being used on foot, and the radio apparatus must therefore be adjusted to the best possible reception quality. On the basis of the detection, the establishment of this operating mode can be made automatically, or in other words without any action on the part of the user. 
   It is also advantageous that a sensor is provided, and that the operating mode can be established as a function of a measured value ascertained by the sensor. This affords a further simple possibility of adjusting the receiver part of the radio apparatus automatically to the best possible signal reception. Depending on the type of sensor selected, virtually arbitrary measurement variables can be made the basis for the establishment of this operating mode. 
   Another advantage [verb missing] in that the sensor detects the charge of a battery connected to the radio apparatus and that the operating mode can be established as a function of the charge of the battery detected by the sensor. In this way it is assured that a switchover to high power consumption in the receiver part of the radio apparatus is made only whenever the voltage made available by the battery does not break in excessively strongly. 
   Another advantage is that an interface is provided for connecting a data processing unit, and that the operating mode can be established as a function of data transmitted to the radio apparatus via the interface. In this way, the reception quality of the receiver part of the radio apparatus can be controlled and programmed from outside by the user. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     One exemplary embodiment of the invention is shown in the drawing and described in further detail in the ensuing description.  FIG. 1  shows a block circuit diagram of a radio apparatus of the invention; and  FIG. 2  is a flow chart for an edt of the radio apparatus. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   In  FIG. 1 , reference numeral  35  identifies a first receiving antenna of a radio apparatus  95  intended for mobile radio. The receiving antenna  35  can be connected via a first switch  135  and a first switch position  140  to a second switch  40  that is controllable. Via the first switch  135 , in a second switch position  145 , a second receiving antenna  115  can be connected to the second switch  40 . Via the second switch  40 , in a first switch position  85 , the input of a pd  10  of a receiver part  1  of the radio apparatus  95  can be connected to the receiving antenna  35 ,  115  connected via the first switch  135 . The receiver part  1  further includes a demodulator  45 , connected on the input side to the output of a reception amplifier  10 ; along with other component groups not shown, the demodulator also includes a mixer  15 . The output of the demodulator  45  can be connected via a third switch  165  in a first switch position  170  to the input of a first filter configuration  100  and in a second switch position  175  to the input of a second filter configuration  105 . The output of the first filter configuration  100  and the output of the second filter configuration  105  are interconnected and are connected to the input of a decoder  50 , which like the two filter configurations  100 ,  105  is also disposed in the receiver part  1  and which can be connected at its output, in a manner known to one skilled in the art, to further receiving components of the radio apparatus, as is indicated by the arrow drawn in dashed lines in  FIG. 1  at the output of the decoder  50 . The output of the decoder  50  is also connected to a first input  60  of an evaluation unit  5 . A second input  65  of the evaluation unit  5  can be connected to a reference potential via a pushbutton switch  30 . A third input  70  of the evaluation unit  5  is connected to a card reader  25 , which is disposed in an insertion slot  20  of the radio apparatus  95 . Via a fourth input  71  of the evaluation unit  5 , the first switch  135  is connected to the evaluation unit  5  so that its switch position can be detected. Via a battery  55 , the second switch  40 , the reception amplifier  10 , the demodulator  40  with the mixer  15 , the third switch  165 , the decoder  50 , the evaluation unit  5 , and the card reader  25  can all be supplied with current. The power supply can be delivered to the reception amplifier  10  via a fourth switch  150  and a first switch position  155 , while conversely in a second switch position  160  of the fourth switch  150  the reception amplifier  10  can be disconnected from the power supply. The fourth switch  150  can also be supplied with current from the battery  55 . For supplying power, the battery  55  can be connected to the applicable components via a fifth switch  180  in a first switch position  185 . The power supply can also be provided externally, however, for instance via the car radio and a motor vehicle, or in general via a power supply adapter  110  for mains operation; the connection with the mains is represented in  FIG. 1  by an arrow drawn in dashed lines at one input of the power supply adapter  110 . For connection of the external power supply, the power supply adapter  110  is connected to the components to be supplied, in a second switch position  90  of the fifth switch  180 . A sensor  120  for detecting the charge status of the battery  55  is connected to the battery  55  and is likewise supplied with current from the battery  55  or the power supply adapter  110 , depending on the switch position, via the fifth switch  180 . Since the sensor  120  is used only for detecting the charge status of the battery  55 , it also suffices to provide the power supply of the sensor  120  only via the battery  55 . The fifth switch  180  is connected to the evaluation unit  5  via a fifth input  72 , and the sensor  120  is connected to the evaluation unit  5  via a sixth input  73 . An external data processing unit  130  is connected to the evaluation unit  5  via an interface  125  and a seventh input  74 . The battery  55  or the power supply adapter  110  also takes on the task of power supply to other reception components, not shown in  FIG. 1 . The evaluation unit  5  has a first output  75  for controlling the power supply to the mixer  15 , a second output  80  for controlling the switch positions of the second and fourth controllable switches  40 ,  150 , and a third output  81  for controlling the switch positions of the also-controllable third switch  165 . In a second switch position  90 , the second switch  40  connects the receiving antenna  35 ,  115 , connected accordingly via the first switch  135 , directly to the output of the reception amplifier  10  and thus to the input of the demodulator  45 , so that the reception amplifier  10  is thereby bypassed. 
   The mode of operation of the evaluation unit  5  will be explained in detail in terms of a flow chart in  FIG. 2 . The flow chart is run through each time a pulse train, also known as a burst, is received. A global variable is introduced that contains the number of successive uninterrupted bursts received without error. This global variable is initialized with zero the first time the flow chart of  FIG. 2  is run through, and at the same time the second switch  40  and the fourth switch  150  are each in their respective second switch position  90 ,  160 ; the power supply to the mixer  15  is reduced to a second predetermined value, and the third switch  165  is in its second switch position  175 . A constant is also provided, which indicates the number of uninterrupted bursts received successively without error after which the receiver part  1  can be operated in a power-saving mode. This constant thus specifies a length of time after which, in the event of error-free signal reception, the sensitivity and/or the signal-to-noise ratio of the receiver part  1  can be reduced. 
   At a program point  200 , the evaluation unit  5  asks whether the card reader  25  in the insertion slot  20  detects a chip card; on the one hand, this realizes an access authorization for the radio apparatus, and on the other it provides for the switchover to an operating mode for testing purposes. Also at this program point  200 , the question is asked whether the second input  65  of the evaluation unit  5  has been connected to the reference potential via the pushbutton switch  30 . The switch position of the first switch  135  and the switch position of the fifth switch  180  are also checked. In this process the question is asked whether the second receiving antenna  115  has been connected to the radio apparatus  95 , and whether the radio apparatus  95  is being supplied with current externally via the power supply adapter  110 . The question is also asked whether the establishment of the operating mode for test purposes has been arranged by the data processing unit  130 . By the evaluation of the signal decoded by the decoder  50 , the question is furthermore asked in the evaluation unit  5  whether a base station has requested the operating mode for test purposes on the part of the radio apparatus  95 , in which the radio apparatus  95  in a so-called echo mode sends a signal, sent previously from the base station to the radio apparatus  95 , back to the base station again for test purposes. Furthermore, by means of the measured signal from the sensor  120 , the question is asked in the evaluation unit  5  whether, at an established first switch position  185  of the fifth switch  180 , there is still a sufficient charge in the battery  55  in order to switch over to high power consumption, without the supply voltage breaking in excessively strongly. If with a sufficient charge in the battery  55  or with the power supply adapter  110  connected at least one of the above conditions is met, then a jump is made to program point  205 ; if not, a jump is made to program point  220 . At program point  205 , the second switch  40  and the fourth switch  150  are switched over by the evaluation unit  5  to the respective first switch position  85 ,  155 , and as a result the reception amplifier  10  in the receiver part  1  is added, unless it had already been added. In this way, the evaluation unit  5  increases the sensitivity of the receiver part  1  to a maximum value. At program point  210 , the power supply of the mixer  15  is raised by the evaluation unit  5  to a first predetermined value, unless this power supply had already been set to that value. In this way, the intermodulation strength of the receiver part  1  is raised to a maximum value, or in other words interference in the useful channel is minimized. At program point  215 , the third switch  165  is switched over by the evaluation unit  5  to its first switch position  170 , and as a result the first filter configuration  100  is switched into the reception signal path, if the first filter configuration  100  has not already been switched into the signal reception path. In this way, the signal-to-noise ratio of the receiver part  1  is increased still further, because neighboring channel interference and interference in the useful channel are largely blanked out in the selected first filter configuration  100 . Depending on the test situation, this task may also be performed better by the second filter configuration  105 , or by other filter configurations, not shown in  FIG. 1 , that can be added via the third switch  165 . The evaluation unit  5  must cause the switch position to be established at the third switch  165  as a function of the test situation prevailing, which it can be informed of for instance by the data processing unit  130  or by the base station. Thus after program step  215  has been executed, the radio apparatus  95  can be tested at maximum performance of its receiver part  1 . An exit from the program is then made. At program point  220 , the question is asked whether the burst received most recently was erroneous. If so, then a jump is made to program point  225 , and if not, to program point  260 . At program point  225 , the global variable is reset to zero. At program point  230 , the question is asked whether at the second output  80  of the evaluation unit  5  a control signal is present which keeps the second switch  40  and the fourth switch  150  in its respective first switch position  85 ,  155 . If so, a jump to program point  235 , and if not to program point  255 , is made. At program point  235 , the question is asked whether the power supply of the mixer  15  has been raised to the first predetermined value by the evaluation unit  5 . If so, then a jump to program point  240  is made, and if not then to program point  250 . In program point  240 , the question is asked whether at the third output  1  of the evaluation unit  5  a control signal is present which keeps the third switch  165  in its first switch position  170 . If so, an exit from the program is made; if not, a jump is made to program point  245 . At program point  245 , the evaluation unit  1  causes the third switch  165  to switch over to its first switch position  170 . Depending on the test situation, some other filter configuration instead of the first filter configuration  100  may be better suited to increasing the reception quality, so that a switchover is made as described above to whichever is the best suited filter configuration. For the present exemplary embodiment, it will always be assumed that this is true for the first filter configuration  100 . After program point  245 , an exit from the program is made. At program point  250 , the power supply of the mixer  15  is raised by the evaluation unit  5  to the first predetermined value. An exit from the program is then made. At program point  255 , the evaluation unit  5  causes the second switch  40  and the fourth switch  150  to switch over into its respective first switch position  85 ,  155 . An exit from the program is then made. 
   At program point  260 , the global variable is incremented. At program point  265 , the question is asked whether the value of the global variable is equivalent to the value of the constant. If so, then a jump to program point  270  is made; if not, an exit from the program is made. At program point  270 , the evaluation unit  5  causes the second switch  40  and the switch  150  to switch over to their respective second switch position  90 ,  160 , if this second switch position  90  has not already been established. At program point  275 , the power supply of the mixer  15  is reduced by the evaluation unit  5  to the second predetermined value, if the power supply of the mixer  15  has not already been set to that value. At program point  280 , the second filter configuration  105  is switched into the transmission path by means of the second switch position  175  of the third switch  165 , or if active filters are used, whichever filter configuration  100 ,  105  consumes less current is used. An exit from the program is then made. 
   The first switch  135  and the fifth switch  180  are embodied noncontrollably, in contrast to the second switch  40 , third switch  165 , and fourth switch  150 . The switchover of the first switch  135  and the fifth switch  180  is also not effected by the evaluation unit  5  but instead occurs upon connection of the radio apparatus  95  to the second receiving antenna  115  or to the external power supply or to the power supply adapter  110 , for instance of the car radio, to which end the two switches  35 ,  180  are advantageously embodied as pressure contacts. If the radio apparatus  95  is disconnected from the car radio, the two switches  135 ,  180  then resiliently return to their first switch position  140 ,  185  for the connection of the first receiving antenna  35  or of the battery  55 . The establishment of the operating mode for test purposes, which leads to optimized reception conditions and is established for instance by actuating the pushbutton switch  30 , can also be used for normal operation, in order to prevent generally poor intelligibility caused by erroneous bursts. 
   An operating menu may also be provided on the radio apparatus  95 , by means of which the user can choose whether he places more value on good reception quality or on a long service life of the battery  55 . This choice can be stored in a memory of the radio apparatus  95 , not shown in  FIG. 1  and connected to the evaluation unit  5 , and can also be monitored as a condition for establishing the operating mode for test purposes. 
   A chip card to be inserted into the insertion slot  20  can also be programmed such that the evaluation unit  5  is made to operate the radio apparatus  95  with the least possible current at all times, including at the expense of reception quality. Finally, it is also conceivable that each user is given what he prefers in terms of the reception quality of the receiver part  1  and the supply life of a battery charge in accordance with a suitably programmed chip card for insertion into the insertion slot  20 , so that the reception quality of the receiver part  1  of the radio apparatus  95  can be adjusted individually for each user. By suitably programming the chip cards, a service provider can also set variably high fees for different levels of reception quality. 
   If the power supply of the mixer  15 , or in other words its operating point, is increased, the result is a mixer characteristic curve in which intermodulation products in the useful frequency range are reduced, and as a result, the attendant influence of interference in the received useful signals is reduced. In the exemplary embodiment described, the evaluation unit  5  has a plurality of opportunities for intervention in order to adapt the sensitivity and/or the signal-to-noise ratio of the receiver part  1  to reception conditions or test conditions. The power consumption is not relevant then if a chip card has been introduced into the insertion slot  20 , for instance for test purposes. In that case, it is not normal telephone operation that is involved but rather a test operating mode. The sensitivity and/or signal-to-noise ratio of the receiver part  1  is therefore increased to the maximum value. 
   In normal operation, a differentiated procedure is realized. If a previously received burst was bad, the sensitivity of the receiver part  1  is first increased, by adding the power-consuming reception amplifier  10 . If this provision is unsuccessful, as indicated by the fact that erroneous reception of the burst again occurs within the specified time, then the intermodulation strength is improved by increasing the operating point or the power supply of the mixer  15 . If even this provision does not lead to the desired success, one skilled in the art can employ further provisions known to him for increasing the sensitivity and/or signal-to-noise ratio of the receiver part  1 , such as adding whichever filter configuration  100 ,  105  is better suited to the particular reception situation, or other provisions not however described in this exemplary embodiment. Only after the time specified by the constant has elapsed with error-free reception having occurred are the power-consuming provisions mentioned rescinded, in order to save power. If by then the reception conditions have still not improved, then once again a maximum of three bursts are lost by erroneous reception until a switchover is again made to maximum sensitivity and/or signal-to-noise ratio of the receiver part  1 . 
   The invention is not limited to radio apparatuses for mobile radio but instead can be employed in all radio traffic applications, such as in cordless telephones, for instance, as well.