JP2015026999A - Receiving device and receiving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a receiving device and a receiving method, which can improve reception performance, in the receiving device that can perform error correction processing on reception information.SOLUTION: A receiving device can use reception information when a signal is received by one radio frame when the signal is received by radio frames subsequent to the one radio frame. The receiving device includes a reception information update determination section 9 which determines whether the reception information when the signal is received by the one radio frame in the subsequent radio frames in response to presence or absence of an error in the signal received by the one radio frame and presence or absence of execution of error correction processing.

Description

  The present invention relates to a receiving apparatus and a receiving method, and more particularly to a technique for improving reception performance of a receiving apparatus that can perform error correction processing on received information.

  Conventionally, in a reception result update process by a communication device, reception information errors may be detected. In this case, whether or not there is an error in the received information is determined. If there is no error in the reception result, update processing is performed. If there is an error, update processing is not performed, and the received information obtained in the previous radio frame. Is used (see, for example, Patent Document 1). Also, for example, in a communication apparatus having a CRC (Cyclic Redundancy Check) error correction function, the result after error correction is determined again, and update processing is performed when there is no error in the result.

JP 2011-199480 A

  However, in the error correction process as described above, an incorrect correction process may be performed. If the received information is updated even though the result after the error correction processing includes an error, the incorrect reception information is updated in the subsequent radio frame. There was a problem that could not be derived.

  Therefore, an object of the present invention is to provide a receiving apparatus and a receiving method capable of improving reception performance in a receiving apparatus capable of performing error correction processing on received information.

The present invention has been made to solve the above-described problem, and the receiving apparatus of the present invention uses reception information when a signal is received in one radio frame as a radio frame subsequent to the one radio frame. A receiving device that can be used when receiving a signal at
Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, whether there is an error in the signal received in the one radio frame, and implementation of error correction processing A reception information update determination unit that is determined based on the presence or absence of the received information.

  In the receiving apparatus of the present invention, when there is an error in the signal received in the one radio frame and error correction processing is performed, the reception information when the signal is received in the one radio frame Is not used in the next and subsequent radio frames.

  In the receiving apparatus of the present invention, it is further determined whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, EVM, phase error, and reception CIR. Preferably, it is determined based on at least one of the frequency offset value and the synchronization position of the radio frame.

Also, the reception method of the present invention is a reception method by a receiving apparatus that can be used when receiving a signal in a radio frame subsequent to the one radio frame. Because
Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, whether there is an error in the signal received in the one radio frame, and implementation of error correction processing A reception information update determination unit that is determined based on the presence or absence of the received information.

  Further, in the reception method of the present invention, when there is an error in the signal received in the one radio frame and error correction processing is performed, the reception information when the signal is received in the one radio frame Is not used in the next and subsequent radio frames.

  In the receiving method of the present invention, whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, EVM, phase error, and reception CIR are further determined. Preferably, it is determined based on at least one of the frequency offset value and the synchronization position of the radio frame.

  According to the present invention, it is possible to provide a receiving apparatus and a receiving method capable of improving reception performance in a receiving apparatus capable of performing error correction processing on received information.

It is a functional block diagram which shows schematic structure of the receiver which concerns on one Embodiment of this invention. It is a flowchart which shows the process of the receiver which concerns on one Embodiment of this invention. It is a flowchart which shows the process of the receiver which concerns on other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a functional block diagram showing a schematic configuration of a receiving apparatus 1 according to an embodiment of the present invention. The receiving device 1 is, for example, a base station, but is not limited thereto, and the present invention can be applied to a communication device, a communication terminal, or the like that receives a signal.

  The receiving apparatus 1 of this embodiment includes a demodulation processing unit 3, a CRC detection unit 5, a CRC error correction processing unit 7, a reception information update determination unit 9, a reception information update processing unit 11, and a reception information storage unit 13.

  The demodulation processing unit 3 demodulates a signal for each radio frame received from a communication terminal or the like via an antenna using reception information described later, and converts the signal into bit data. The demodulation processing unit 3 sends bit data obtained by demodulating the reception signal to the CRC detection unit 5 and sends reception information to the reception information update determination unit 9. In the present embodiment, the reception information includes a frequency offset value, a synchronization timing position, and the like.

  The CRC detection unit 5 performs CRC error detection on the bit data acquired from the demodulation processing unit 3 and determines the presence or absence of an error. The CRC detection unit 5 sends bit data to the CRC error correction processing unit 7 when an error is detected as a result of CRC error detection. If no error is detected, no bit data is sent to the CRC error correction processing unit 7 and the CRC error detection result is sent to the reception information update determination unit 9.

  The CRC error correction processing unit 7 performs CRC error correction processing on the bit data acquired from the CRC detection unit 5, and sends the result after CRC error correction to the reception information update determination unit 9.

  The reception information update determination unit 9 acquires reception information from the demodulation processing unit 3. The CRC error detection result is acquired from the CRC detection unit 5. Also, bit data after error correction is acquired from the CRC error correction processing unit 7. The reception information update determination unit 9 performs CRC error detection again on the reception information acquired from the demodulation processing unit 3 or the bit data after error correction acquired from the CRC error correction processing unit 7. If an error is detected as a result of CRC error detection, the reception information derived from the current radio frame is not used (not taken over), for example, reception information of the radio frame immediately before the current radio frame. Is used (takes over). If no error is detected, the CRC error correction processing unit 7 determines whether or not CRC error correction processing has been performed. If CRC error correction processing has not been performed, the current radio frame is used. Use the derived reception information. In addition, when CRC error correction processing has been performed, reception information derived from the current radio frame is not used because there is a risk of error correction. The reception information update determination unit 9 sends the reception information to be used based on the above determination to the reception information update processing unit 11.

  The reception information update processing unit 11 performs a process for updating the reception information acquired from the reception information update determination unit 9. The reception information that has been updated by the reception information update processing unit 11 is stored in the reception information storage unit 13. The reception information stored in the reception information storage unit 13 can be sent to the demodulation processing unit 3.

  Next, regarding the reception method performed by the reception apparatus 1 according to an embodiment of the present invention, the determination of update of reception information will be described with reference to the flowchart shown in FIG.

  First, the demodulation processing unit 3 demodulates a signal received from a communication terminal or the like via an antenna and converts it into bit data (step S11).

  Next, the CRC detection unit 5 performs CRC error detection on the bit data acquired from the demodulation processing unit 3 (step S12).

  If an error is detected in step S12 (“Yes” in step S12), the CRC error correction processing unit 7 performs CRC error correction processing (step S13), and the reception information update determination unit 9 performs CRC again. Error detection is performed (step S14).

  If no error is detected in step S12 ("No" in step S12), the error is not sent to the CRC error correction processing unit 7, the result is notified to the reception information update determination unit 9, and CRC error detection is performed again. (Step S14). If no error is detected in step S12 (“No” in step S12), it is possible to determine that there is no error in step S14 without performing CRC error detection again.

  If an error is detected in the CRC error detection performed by the reception information update determination unit 9 ("Yes" in step S14), the reception information derived from the current radio frame is not used (not taken over). (Step S15), the process ends.

  If no error is detected in the CRC error detection performed by the reception information update determination unit 9 (“No” in step S14), whether or not the CRC error correction processing unit 7 has performed the CRC error correction processing. Is determined (step S16). If the reception information update determination unit 9 determines that error correction has been performed (“Yes” in step S16), the reception information derived in the current radio frame is not used (not inherited) (step S17). ), The process ends.

  Here, when the reception information derived in the current radio frame is not used, for example, the reception information in the previous radio frame can be used.

  If the reception information update determination unit 9 determines that error correction has not been performed (“No” in step S16), the reception information derived from the current radio frame is used (updated) (step S16). S18), the process ends.

  The receiving apparatus 1 according to the present embodiment as described above determines whether to use the reception information of the current radio frame based on whether CRC error correction is performed as well as the CRC error correction result. Therefore, when the error correction function performs an incorrect correction process, it is possible to prevent updating with incorrect information. Therefore, it is no longer possible to derive a normal reception result because the incorrect reception information is updated, and the reception performance can be improved.

  In addition, when the present invention is applied to a base station, reception performance particularly in a weak electric field is improved. This is because there are many cases where the CRC error correction result is erroneous correction and the received information is updated in a state where there is no signal input or a weak electric field. By preventing the case according to the present invention, the communication area can be expanded. In addition, when the present invention is applied to a mobile station, it is possible to improve the connection rate by improving reception performance.

(Other embodiments)
Next, as another embodiment of the present invention, a receiving apparatus in which a condition for determining update of received information is added to the previous embodiment will be described.

  In the previous embodiment, when CRC error correction processing is performed, it is assumed that there is a possibility of error correction, and the reception information of the current wireless frame is not used. However, CRC error correction is performed correctly. You may consider the case. In this case, when an error correction process is performed, an additional condition determination (hereinafter referred to as an additional determination) is further performed. And when the said conditions are satisfy | filled, the reception information in the present radio | wireless frame is utilized as what has high reliability.

  Additional conditions include, for example, values such as EVM (error vector amplitude), phase error, reception CIR (power ratio), difference in frequency offset value between consecutive radio frames, and difference in synchronization position between consecutive radio frames. Can be used. As a condition for determination using the EVM value, for example, the condition can be satisfied when the EVM value of the current radio frame is smaller than a predetermined value. As a condition for determination using the value of the phase error, for example, the condition can be satisfied when the value of the phase error of the current radio frame is larger than a predetermined value. As a determination condition using the value of the reception CIR, for example, the condition can be satisfied when the value of the reception CIR of the current radio frame is larger than a predetermined value. The determination condition using the frequency offset value is, for example, a condition in which the difference between the frequency offset value of the previous radio frame and the frequency offset value of the current radio frame is smaller than a predetermined value. Can be satisfied. As a condition for determination using the synchronization position, for example, the condition is satisfied when the difference between the synchronization position of the previous radio frame and the synchronization position of the current radio frame is smaller than a predetermined value. can do.

  In this embodiment, at least one of the above conditions or a combination of two or more conditions is used as an additional condition in the reception information update determination unit 9 in the block diagram shown in FIG. To implement.

  Next, determination of update of reception information in the reception method according to the present embodiment will be described with reference to the flowchart shown in FIG. Note that description of the same processing as in the previous embodiment is omitted.

  When the CRC error detection performed by the reception information update determination unit 9 does not detect an error (“No” in step S24), and the CRC error correction processing unit 7 determines that the CRC error correction processing has been performed (step S24) In this embodiment, the reception information update determination unit 9 further performs addition determination (“Yes” in S26) (step S27).

  If the additional determination is satisfied (“Yes” in step S27), it is determined that CRC error correction is correctly performed, and the reception information derived from the current radio frame is used (updated). (Step S28), the process ends. If the addition determination is not satisfied (“No” in step S27), it is determined that the CRC error correction processing performed by the CRC error correction processing unit 7 was erroneous correction, and the current wireless frame is used. The derived reception information is not used (step S25), and the process ends.

  According to the receiving apparatus and the receiving method of this embodiment, when CRC error correction is correctly performed, the reception information of the current frame can be used, so that the reception information for each successive radio frame is more effective. Can be used. In addition, more reliable received information can be updated, and as a result, communication performance can be further improved.

  Here, in the above embodiment, the case where the CRC error correction function is used as the error correction function has been described as an example. However, the present invention is not limited to this, for example, turbo encoding, Viterbi decoding of a convolutional code, or the like. The present invention can also be applied to cases having an error correction function using the.

DESCRIPTION OF SYMBOLS 1 Reception apparatus 3 Demodulation process part 5 CRC detection part 7 CRC error correction process part 9 Reception information update determination part 11 Reception information update process part 13 Reception information storage part

Claims (6)

A reception device that can be used when receiving a signal in a radio frame subsequent to the one radio frame, the reception information when the signal is received in one radio frame,
Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, whether there is an error in the signal received in the one radio frame, and implementation of error correction processing A reception apparatus comprising: a reception information update determination unit that is determined based on the presence or absence of the reception information.   When the signal received in the one radio frame has an error and error correction processing is performed, the reception information when the signal is received in the one radio frame is not used in the next and subsequent radio frames. Item 4. The receiving device according to Item 1.   Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames is further determined in terms of EVM, phase error, reception CIR, frequency offset value, and synchronization position of the radio frame. The receiving device according to claim 1, wherein the receiving device is determined based on at least one of the values. Receiving information when receiving a signal in one radio frame is a receiving method by a receiving apparatus that can be used when receiving a signal in a radio frame subsequent to the one radio frame,
Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames, whether there is an error in the signal received in the one radio frame, and implementation of error correction processing A receiving method, wherein the receiving method is determined based on the presence or absence of   When the signal received in the one radio frame has an error and error correction processing is performed, the reception information when the signal is received in the one radio frame is not used in the next and subsequent radio frames. Item 5. The receiving method according to Item 4.   Whether or not reception information when a signal is received in the one radio frame is used in the next and subsequent radio frames is further determined in terms of EVM, phase error, reception CIR, frequency offset value, and synchronization position of the radio frame. The reception method according to claim 4, wherein the reception method is determined based on at least one of the values.

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