KR20080108237A - Diversity reception device - Google Patents

Abstract

It is possible to provide a diversity reception device capable of reducing power consumption and increasing a battery service life by detecting a difference of reception qualities between reception branches and controlling start/stop of diversity operation according to the difference of the reception qualities. According to a difference between reception levels (A, B) as reception qualities of reception branches (13a, 13b), it is judged whether a desired diversity effect can be obtained. If it is judged that the desired diversity effect cannot be obtained, the diversity operation is stropped and power supply to the reception branch not to be used is stopped and the synthesis process operation is stopped. ® KIPO & WIPO 2009

Description

Diversity Receiver {DIVERSITY RECEPTION DEVICE}

The present invention relates to a diversity receiver having a plurality of reception branches including an antenna, a receiver, and a demodulator.

Conventional diversity receivers include those using antenna switching diversity and those using synthetic diversity (see, for example, Japanese Patent Application Laid-Open No. 2000-183793). The former has the advantage of low power consumption, and the latter has the advantage of obtaining a high diversity effect.

12 is a diagram illustrating diversity gain with respect to a difference in reception levels between reception branches in conventional diversity reception. In this figure, the horizontal axis is Carrier to Noise ratio (C / N), and the vertical axis is BER (Bit Error Rate). This figure shows the BER characteristics when the reception level difference between the reception branches at the time of diversity reception is 0 dB, 4 dB, and 8 dB, and the BER characteristics at the time of reception in a single branch. The characteristic Ch1 is a BER characteristic when the level difference between reception branches is 0 dB at the time of diversity reception. The characteristic Ch2 is a BER characteristic when the level difference between reception branches is 4 dB at the time of diversity reception. The characteristic Ch3 is a BER characteristic when the level difference between reception branches is 8 dB at the time of diversity reception. The characteristic Ch4 is a BER characteristic at the time of single branch reception. Point (a), point (b), point (c), and point (d) are C / N values of sensitivity points in BER of characteristics (Ch1, Ch2, Ch3, Ch4).

In addition, the diversity gain G1 is obtained at the sensitivity point of the BER characteristic when the level difference between the reception branches is 0 dB in the diversity reception of the characteristic Ch1 with respect to the BER characteristic in the single branch reception of the characteristic Ch4. Diversity gain (point (d)-point (a)). Similarly, the diversity gain G2 is at the sensitivity point of the BER characteristic when the level difference between reception branches is 4 dBd in the diversity reception of the characteristic Ch2 relative to the BER characteristic in the single branch reception of the characteristic Ch4. Diversity gain (point (d)-point (b)). Similarly, the diversity gain G3 is the sensitivity point of the BER characteristic when the level difference between reception branches is 8 dBd at the time of the diversity reception of the characteristic Ch3 to the BER characteristic at the time of the single branch reception of the characteristic Ch4. Diversity gain at (point d-point c).

The BER characteristic at the time of diversity reception becomes closer to the BER characteristic at the time of single branch reception as the level difference between reception branches becomes larger, and the diversity gain by diversity reception becomes smaller. In other words, when the level difference between reception branches is somewhat large, it becomes the same as when receiving a single branch.

However, since the conventional diversity receiver performs the diversity operation regardless of the magnitude of the diversity gain, there is a problem in that it consumes power unnecessarily. That is, when there is a difference in antenna gain of each reception branch or when there is a difference in noise figure (NF) or gain in each reception branch, the difference in reception quality (reception level, etc.) between reception branches is different. Even when this cursor diversity effect is not obtained, the diversity reception operation is performed, thus consuming unnecessary power. In particular, since small electronic devices such as mobile phones use miniaturized batteries, it is not possible to extend the duration of the battery when it consumes unnecessary power. That is, in the related art, a synthetic diversity operation with a large power consumption is performed unnecessarily, and thus the increased power is consumed unnecessarily, so that the battery duration is short.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a diversity receiver capable of performing a diversity operation according to the magnitude of diversity gain.

The above object is achieved by the following configuration.

Diversity receiving apparatus of the present invention is a diversity receiving apparatus having a plurality of receiving branches having an antenna, a receiving unit and a demodulation unit, the difference between the plurality of receiving branches of the reception quality obtained in each of the plurality of receiving branches. Control the starting and stopping of the diversity operation by changing the ratio between the diversity reception operation using the plurality of reception branches and the single branch reception operation according to the reception quality difference detection means for detecting and the reception quality difference between the plurality of reception branches. And diversity operation control means.

The diversity receiver of the present invention includes power supply control means for controlling power supply to each of the plurality of reception branches, and synthesis processing means for synthesizing demodulation signals from each of the plurality of reception branches, The power supply control unit feeds power to each of the plurality of reception branches when controlling the diversity reception operation by the diversity operation control means, and does not perform the reception operation among the plurality of reception branches when controlling the single branch reception operation. Feeding to the receiving branch is stopped, and the combining processing means stops the combining processing operation upon controlling the single branch receiving operation by the diversity operation controlling means.

In the diversity receiving apparatus of the present invention, the receiving quality difference detecting means receives at least one of a reception level, an AGC level, a bit error rate, a packet error rate, a ratio of carrier and noise of each of the plurality of reception branches. Detect the difference in quality.

The program of the diversity receiver according to the present invention is a program of a diversity receiver having a plurality of reception branches including an antenna, a receiver, and a demodulator, wherein the plurality of reception branches of the reception quality obtained in each of the plurality of reception branches are provided. Detecting a difference between the plurality of reception branches and controlling the start and stop of the diversity operation by changing a ratio between the diversity reception operation using the plurality of reception branches and the single branch reception operation according to the difference in the reception quality between the plurality of reception branches. And performing each of the above steps on a computer.

The diversity receiver of the present invention can save power by adapting the diversity effect to start and stop the diversity operation, so that the battery duration can be extended when applied to miniaturized electronic devices such as mobile phones. Can be.

1 is a block diagram showing a schematic configuration of a diversity receiver according to a first embodiment of the present invention.

Fig. 2 is a diagram showing an example of variation in reception level in each reception branch of the diversity receiver according to the first embodiment of the present invention.

Fig. 3 is a diagram showing an example of variation in reception level in each reception branch of the diversity receiver according to the first embodiment of the present invention.

Fig. 4 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the first embodiment of the present invention.

Fig. 5 is a block diagram showing a schematic configuration of a diversity receiver according to a second embodiment of the present invention.

Fig. 6 is a diagram showing an example of variation in error rate (BER) in each reception branch of the diversity receiver according to the second embodiment of the present invention.

Fig. 7 is a diagram showing an example of variation of the error rate (BER) in each reception branch of the diversity receiver according to the second embodiment of the present invention.

Fig. 8 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the third embodiment of the present invention.

Fig. 9 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the fourth embodiment of the present invention.

Fig. 10 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the fifth embodiment of the present invention.

Fig. 11 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the sixth embodiment of the present invention.

12 is a diagram showing diversity gain with respect to reception level differences between reception branches in conventional diversity reception.

(Explanation of symbols for the main parts of the drawing)

1a, 1b antenna

2a, 2b receiver

3a, 3b demodulator

4 Synthesis Processing Unit

5 reception quality difference detection unit

6 diversity operation control unit

7 power control unit

13a, 13b receive branch

EMBODIMENT OF THE INVENTION Hereinafter, the preferred embodiment for implementing this invention is demonstrated in detail with reference to drawings.

1 is a block diagram showing a schematic configuration of a diversity receiver according to a first embodiment of the present invention. In this figure, the diversity receiver according to the present embodiment receives terrestrial digital broadcasting, for example, and includes two branches, a reception branch 13a and a reception branch 13b. The reception branch 13a includes an antenna 1a, a receiver 2a for receiving a high frequency (RF) signal captured by the antenna 1a, converting the signal into a baseband signal, and outputting the baseband signal, and a baseband signal from the receiver 2a. And a demodulation section 3a for demodulating and outputting a digital signal. The reception branch 13b, like the reception branch 13a, has an antenna 1b, a receiver 2b for receiving a high frequency (RF) signal captured by the antenna 1b, converting it into a baseband signal, and outputting the baseband signal, and a receiver ( A demodulation section 3b for demodulating the baseband signal from 2b) and outputting a digital signal is provided. The receivers 2a and 2b input the received signals S8a and S8b to the reception quality difference detection unit 5.

In addition to the above-described configuration, the diversity receiver of the present embodiment includes a synthesis processor 4 for synthesizing the digital signals from the demodulators 3a and 3b, and the received signals S8a and S8b obtained from the receivers 2a and 2b. And a determination of starting and stopping of the diversity operation on the basis of the detection result of the reception quality difference detection unit 5 and the reception quality difference detection unit 5 for detecting the difference between the two, and the indication signal S10 based on the result. Control unit 6 for inputting the power to the power control unit 7 and the power supply control unit for controlling the power supply to the reception branches 13a and 13b according to the instruction signal S10 from the diversity operation control unit 6 ( 7) is provided.

The reception quality difference detection unit 5 includes an A / D conversion circuit (not shown), and digitally converts the reception signals S8a and S8b from the reception units 2a and 2b and detects these differences. That is, after digitally converting the received signal S8a from the receiver 2a and the received signal S8b from the receiver 2b, respectively, the difference is obtained to generate the difference signal S9, and the diversity operation control unit 6 ). The diversity operation control unit 6 performs diversity reception operation using the reception branches of the reception branches 13a and 13b according to the difference signal S9 from the reception quality difference detection unit 5, and the reception branches 13a and 13b. It is to control the start and stop of the diversity operation by changing the ratio with the reception operation in a single branch using either one. That is, the diversity operation control unit 6 determines the presence or absence of the desired diversity effect on the basis of the difference signal S9, and generates the instruction signals S10 and S12 for instructing the start and stop of the diversity operation.

That is, the diversity operation control unit 6 compares the difference signal S9 with a predetermined value X for determining the presence or absence of a desired diversity effect, and when the difference signal S9 is larger than the predetermined value X, It is determined that the desired diversity effect cannot be obtained, and control for stopping the diversity operation is performed. That is, the instruction signals S10 and S12 for instructing the stop of the diversity operation are generated and input to the power supply control unit 7 and the synthesis processing unit 4. In contrast, when the difference signal S9 is equal to or less than the predetermined value X, it is determined that the desired diversity effect can be obtained, and control is performed to stop the diversity operation. That is, the instruction signals S10 and S12 for instructing the start of the diversity operation are generated and input to the power supply control unit 7 and the synthesis processing unit 4.

The determination of the difference signal S9 with respect to the predetermined value X is performed in a predetermined time and a predetermined number of times. The predetermined value X, the predetermined time, and the predetermined number of times are set to a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM), which are not shown.

When the instruction signal S12 from the diversity operation controller 6 is an instruction that the diversity operation is not stopped, the synthesis processor 4 combines the demodulated signals obtained by synthesizing the digital signals from the demodulators 3a and 3b. Output On the other hand, when the instruction signal S12 is an instruction to stop the diversity operation, the signal to be used without synthesizing the digital signals from the demodulators 3a and 3b is output as a demodulation signal. When the instruction signal S10 from the diversity operation controller 6 indicates that the diversity operation is not stopped, the power supply control unit 7 supplies a feed signal S11a to perform power feeding to the reception branches 13a and 13b. , S11b). When the instruction signal S10 is an instruction to stop the diversity operation, power is supplied to the reception branch used in the reception branches 13a and 13b, and power supply is stopped for the reception branch not in use. For example, when using the reception branch 13a, the feed signal S11a is input only to the reception branch 13a. In the reverse case, the feed signal S11b is input only to the reception branch 13b.

2 and 3 are diagrams showing examples of level variations of the received signals of the respective reception branches 13a and 13b of the diversity receiver according to the present embodiment. 2 and 3, the reception level A is the signal level of the reception signal S8a at the timing t1 of the reception unit 2a. The reception level B is a signal level of the reception signal S8b at the timing t1 of the reception unit 2b.

In Fig. 2, the difference Y1 between the reception level A and the reception level B indicates the difference between the reception quality of the reception branch 13a and the reception branch 13b. The difference Y1 is input to the diversity operation control section 6 as the difference signal S9 and compared with a predetermined value X for determining the presence or absence of the desired diversity effect. In this case, when the difference signal S9 is larger than the predetermined value X, the difference between the reception quality of the reception branch 13a and the reception quality of the reception branch 13b is large and a desired diversity effect cannot be obtained. to be. In Fig. 3, the difference Y2 between the reception level A and the reception level B indicates the difference between the reception quality of the reception branch 13a and the reception branch 13b. The difference Y2 is input to the diversity operation control section 6 as the difference signal S9 and compared with a predetermined value X for determining the presence or absence of the desired diversity effect. In this case, when the difference signal S9 is equal to or less than the predetermined value X, the difference between the reception quality of the reception branch 13a and the reception quality of the reception branch 13b is small so that a desired diversity effect can be obtained. .

4 is a flowchart for explaining start stop control of the diversity operation in the diversity receiving apparatus according to the present embodiment. In Fig. 4, steps S1 to S8 represent steps of start stop control of diversity operation. First, the diversity operation control section 6 starts the diversity start stop control immediately after the diversity operation starts or as an interrupt process during the diversity operation (step S1). After the start of the diversity start stop control, the diversity operation control section 6 determines whether the reception branch 13a and the reception branch 13b are in the diversity operation (step S2). If the diversity operation is not in progress, the process ends. In contrast, when the diversity operation is performed, the reception quality difference detection unit 5 detects the reception quality (the reception levels A and B in Figs. 2 and 3) of the respective reception branches 13a and 13b (step S3). ).

Subsequently, it is determined whether or not the detection of the difference in reception quality is performed for a predetermined time and a predetermined number of times (step S4). That is, the diversity operation control section 6 detects the difference in reception quality (the differences Y1 and Y2 in Figs. 2 and 3) for a predetermined time and a predetermined number of times. For example, let it be an average value in predetermined time (1 second) and predetermined number of times (once). If the detection of the difference in reception quality is not performed for a predetermined time or a predetermined number of times, this determination process is repeated until this detection is performed, and in the case of detecting the difference in reception quality for a predetermined time and a predetermined number of times, the step is performed. Shift to S5. In step S5, the difference in reception quality (differences Y1 and Y2 in Figs. 2 and 3) is compared with a predetermined value X for determining the presence or absence of a desired diversity effect. Here, when the difference Y1 is larger than the predetermined value X as shown in FIG. 2, it becomes determination NO, and it transfers to step S7. On the other hand, if the difference Y2 is equal to or less than the predetermined value X as shown in Fig. 3, the determination is YES, and the flow proceeds to step S6. In step S6, the diversity operation of the reception branches 13a and 13b is continued. On the other hand, in step S7, the diversity operation is stopped. That is, the power supply from the power supply control part 7 is stopped and either the synthesis processing operation | movement stops which one of the reception branches 13a and 13b is set as the unused reception branch. In step S8, diversity start stop control is terminated. This diversity start stop control occurs as an interrupt process.

According to the diversity receiving apparatus according to the present embodiment as described above, a diver who desires according to the difference between the reception level A which is the reception quality of the reception branch 13a and the reception level B which is the reception quality of the reception branch 13b is desired. If it is determined whether or not the city effect can be obtained, and if it is determined that the desired diversity effect cannot be obtained, the diversity operation is stopped, and power supply to the receiving branch that is not in use is stopped and synthesis is performed. Stop the processing operation. For this reason, electric power can be saved, and battery duration can be extended when it is applied to miniaturized electronic devices, such as a mobile telephone.

5 is a block diagram showing a schematic configuration of a diversity receiver according to a second embodiment of the present invention. In FIG. 5, the diversity receiver according to the present embodiment has two branches of the reception branches 13a and 13b, similarly to the diversity receiver according to the first embodiment, and uses the error rate BER as the reception quality. Diversity operation is controlled. In addition, in FIG. 5, the same reference numerals as those in FIG. 1 perform the same operations, and thus description thereof will be omitted. The reception quality difference detection unit 5 includes an A / D conversion circuit (not shown), and detects a difference in reception quality of the reception branches 13a and 13b. That is, error rates S13a and S13b are input from the demodulators 3a and 3b, these differences are detected, and the difference signal S14 is input to the diversity operation control unit 6.

6 and 7 are diagrams showing an example of variation in the error rate BER in the reception branches 13a and 13b of the diversity receiver according to the present embodiment. 6 and 7, the error rate A is the error rate S13a at the timing t1 of the demodulator 3a. The error rate B is the error rate S13b at the timing t1 of the demodulator 3b. In particular, in FIG. 6, the difference Y1 between the error rate A and the error rate B indicates a difference in reception quality between the reception branch 13a and the reception branch 13b. The difference Y1 is input to the diversity operation control section 6 as the difference signal S14 and compared with a predetermined value X for determining the presence or absence of the desired diversity effect. In this case, the difference signal S14 is larger than the predetermined value X. The difference between the reception quality of the reception branch 13a and the reception quality of the reception branch 13b is large, so that the desired diversity effect cannot be obtained. Indicates the state.

Similarly, in Fig. 7, the difference Y2 between the error rate A and the error rate B indicates the difference in reception quality between the reception branch 13a and the reception branch 13b. The difference Y2 is input to the diversity operation control section 6 as the difference signal S14 and compared with a predetermined value X for determining the presence or absence of the desired diversity effect. In this case, when the difference signal S14 is equal to or less than the predetermined value X, the difference between the reception quality of the reception branch 13a and the reception quality of the reception branch 13b is small, so that a desired diversity effect can be obtained. Indicates.

Since the start stop control of the diversity operation in the diversity receiver according to the present embodiment is almost the same as the start stop control of the diversity operation in the diversity receiver according to the first embodiment, only different parts will be described. (See FIG. 4).

First, the reception quality difference detection unit 5 detects the reception quality (error rates A and B in Figs. 6 and 7) of each of the reception branches 13a and 13b (step S3). The diversity operation control section 6 determines whether the detection of the difference in the reception quality (the differences Y1 and Y2 in Figs. 6 and 7) has been performed for a predetermined time and a predetermined number of times (step S4). For example, let it be an average value in predetermined time (1 second) and predetermined number of times (once). In the case of determination NO, the process is repeated until determination YES, and when the determination YES is reached, step S5 is reached. In step S5, the difference in reception quality (differences Y1 and Y2 in Figs. 6 and 7) is compared with a predetermined value X for determining the presence or absence of the desired diversity effect, and the difference ( If Y1) is larger than the predetermined value X, it is determined NO and the process proceeds to step S7. In contrast, when the difference Y2 is equal to or less than the predetermined value X as shown in FIG. 7, the determination is YES, and the flow proceeds to step S6.

According to the diversity receiver according to the present embodiment, the difference between the error rate BER (A), which is the reception quality of the reception branch 13a, and the error rate BER, B, which is the reception quality of the reception branch 13b, is determined. Therefore, it is determined whether or not the desired diversity effect can be obtained, and when it is determined that the desired diversity effect cannot be obtained, the diversity operation is stopped, and power supply to the receiving branch that is not used is stopped. At the same time, the synthesis processing operation is stopped. For this reason, electric power can be saved, and battery duration can be extended when it is applied to miniaturized electronic devices, such as a mobile telephone.

Fig. 8 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the third embodiment of the present invention. In Fig. 8, steps S1 to S8 indicate the step of starting stop control of the diversity operation, and the steps denoted by the same reference numerals as Fig. 4 shown in Fig. 8 perform the same operation, and thus description thereof is omitted.

In Fig. 8, in step S5, for example, the predetermined value X is set to 2 dB, and when the difference between the reception levels A and B is less than or equal to the predetermined value (X = 2 dB), the determination is YES and the step S6. To. In step S6, the diversity operation of the reception branches 13a and 13b is continued and operated at 100% of the activation rate. Here, the activation rate represents the rate at which the diversity operation is started at a predetermined time, and the activation rate 100% indicates that the diversity operation continues to operate at the predetermined time. In addition, the activation rate of 0% indicates that the diversity operation continues to stop.

On the other hand, when the difference between the reception levels A and B is larger than the predetermined value (X = 2 dB), the determination is made to NO and the process proceeds to step S9. In step S9, for example, the predetermined value W is set to 4 dB, which becomes a predetermined value X <W, and the reception quality difference (the difference Y1 in FIG. 2 and the difference Y2 in FIG. 3) and the desired The predetermined value W for determining the presence or absence of the diversity effect is compared. As shown in FIG. 2, when difference Y1 is larger than predetermined value (W = 4dB), it becomes judgment NO and it moves to step S7. On the other hand, as shown in FIG. 3, when difference Y2 is below predetermined value (W = 4dB), it becomes determination YES, and it transfers to step S10.

In step S10, the divergence operation of the diversity operation of the reception branches 13a and 13b is made to K%. Here, the activation rate (K%) is 0% <K <100%. For example, when the activation rate K is 90%, the diversity operation is started at 90% of a predetermined time, and 10% Is a state where the diversity operation is stopped.

In Embodiment 1 described above, the diversity start or diversity stop is determined by using a single predetermined value X to determine the presence or absence of the desired diversity effect. A plurality of predetermined values (X and W) are set to determine the presence or absence, and the diversity ratio is changed by changing the ratio between the diversity reception operation and the single branch reception operation according to the difference in the reception quality of the reception branches 13a and 13b. The start and stop of operation is controlled.

According to the diversity receiver according to the present embodiment as described above, whether or not the desired diversity effect can be obtained according to the difference between the reception levels A and B, which are reception quality of the reception branches 13a and 13b. If it is determined that the desired diversity effect cannot be obtained, the activation rate of the diversity operation is changed, and the feeding to the unused receiving branch is stopped and synthesized at the time of the receiving operation in a single branch. Stop the processing operation. Therefore, the diversity operation is stopped in response to the diversity effect, so that power can be saved, and the battery duration can be extended when applied to miniaturized electronic devices such as mobile phones.

Fig. 9 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the fourth embodiment of the present invention. FIG. 9 differs in that step S11 is added to FIG. 4, and the same reference numerals as those of FIG. 4 perform the same operation, and thus description thereof will be omitted.

In FIG. 9, step S11 shows the operation after stopping the diversity operation of step S7, and starts the diversity operation after waiting for a predetermined time, for example, 1 second, and then proceeds to step S3. do. By this operation, a determination is made to return to the diversity operation again after the diversity operation is stopped in step S7.

According to the diversity receiver according to the present embodiment, when the diversity operation is stopped because it is determined that the desired diversity effect cannot be obtained, the diversity operation is started again after waiting for a predetermined time. Diversity operation can be continued unless the power supply is turned off.

Fig. 10 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the fifth embodiment of the present invention. FIG. 10 differs in that the steps S12 and S13 are added to FIG. 4, and the same reference numerals as those of FIG. 4 perform the same operation, and thus description thereof will be omitted.

In Fig. 10, step S12 is an operation after stopping the diversity operation of step S7, and after receiving a predetermined time, for example, one second, the reception quality of a single branch, for example, an error rate BER, is shown. The process proceeds to step S13. In step S13, when the detected error rate BER is less than or equal to the predetermined value R, the process proceeds to step S3. When the detected error rate BER is larger than the predetermined value R, the flow goes to step S12. Go back. By this operation, after stopping the diversity operation in step S7, a determination is made to return to the diversity operation again in accordance with the reception quality of the single branch.

According to such a diversity receiver according to the present embodiment, when it is determined that a desired diversity effect cannot be obtained and the diversity operation is stopped, an error rate that is a reception quality of a single branch is detected after waiting for a predetermined time. Since the diversity operation is started again when the detected error rate is equal to or less than the predetermined value R, the diversity operation can be continued unless the power supply of the apparatus is turned off.

Fig. 11 is a flowchart for explaining start stop control of diversity operation in the diversity receiving apparatus according to the sixth embodiment of the present invention. FIG. 11 differs in that step S14 is added to FIG. 8, and the same reference numerals as those of FIG. 8 perform the same operation, and thus description thereof will be omitted.

In Fig. 11, step S14 is an operation after stopping the diversity operation of step S7 or an operation after continuing the diversity operation at the activation rate (K%) of step S10, for a predetermined time, for example. For example, after one second of waiting, the diversity operation is started to proceed to step S3. By this operation, a determination is made to return to the diversity operation again after the processing of step S7 or step S10.

According to such a diversity receiver according to the present embodiment, when the diversity operation is stopped by determining that the desired diversity effect cannot be obtained, or when the diversity operation is performed at the activation rate (K%), Since the diversity operation is started again after waiting for time, the diversity operation can be continued unless the power supply of the apparatus is turned off.

Further, in the first, third, fourth, and sixth embodiments, differences in the reception quality of the reception branches 13a and 13b are detected from the reception levels A and B in the reception units 2a and 2b. In 5, the difference in the reception quality of the reception branches 13a and 13b is detected from the error rates BER (A and B) at the receivers 2a and 2b, but the AGC (Automatic Gain Control) at the receivers 2a and 2b is detected. The same effect can also be obtained by detecting from the ()) level, PER (packet error rate) or C / N (carrier to noise ratio). In this case, any two or more of the reception level, AGC level, BER, PER, and C / N may be combined.

In addition, in the first to sixth embodiments, the case where there is a difference in the performance of the antenna such as the antenna gain and directivity of the antennas 1a and 1b has not been described. By the point, the same effect can be obtained.

Further, in the first to sixth embodiments, detection of the difference in reception quality is set as an average value of a predetermined time (1 second) and a predetermined number of times (one time), but for example, a predetermined time (0.1 second) and a predetermined number of times (three times). The same effect can be obtained also by detecting the average value or the peak value by the intermittent operation.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

The present invention has the effect of saving battery power and extending battery life, and is applicable to a diversity receiver using a plurality of reception branches, particularly a mobile phone or a car navigation system capable of receiving terrestrial digital broadcasting. .

Claims (4)

A diversity receiver having a plurality of reception branches having an antenna, a receiver, and a demodulator, Reception quality difference detection means for detecting a difference between the plurality of reception branches of the reception quality obtained in each of the plurality of reception branches; Diversity operation control means for controlling the start and stop of the diversity operation by changing the ratio of the diversity reception operation and the single branch reception operation using the plurality of reception branches according to the difference in the reception quality between the plurality of reception branches. Diversity receiver. The method of claim 1, Power supply control means for controlling a power supply to each of the plurality of reception branches; Synthesis processing means for synthesizing demodulated signals from each of the plurality of reception branches; The power supply control unit feeds power to each of the plurality of reception branches when controlling the diversity reception operation by the diversity operation control means, and does not perform the reception operation among the plurality of reception branches when controlling the single branch reception operation. Stop feeding to the receiving branch, And said synthesizing processing means stops the synthesizing processing upon controlling the single branch reception operation by said diversity operation controlling means. The method according to claim 1 or 2, The reception quality difference detecting means detects the difference in reception quality by using any one or more of a reception level, an AGC level, a bit error rate, a packet error rate, a ratio of carrier and noise of each of the plurality of reception branches. Diversity receiving device. A program of a diversity receiver having a plurality of reception branches having an antenna, a receiver, and a demodulator, Detecting a difference between the plurality of reception branches of a reception quality obtained in each of the plurality of reception branches; And controlling the start and stop of the diversity operation by changing a ratio between the diversity reception operation using the plurality of reception branches and the single branch reception operation according to the difference in the reception quality between the plurality of reception branches. A program that executes steps on a computer.

Images