JPH1155206A - Error compensation method and multi-carrier transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need of adding code error detection signals to data for respective carriers by measuring carrier quality on a reception side and estimating the specification of the occurred part of a code error by means of carrier quality when the code error occurs in a transmission channel. SOLUTION: The quality of transmitted data is measured in a carrier signal quality measuring part 17 and a use carrier decision part 18 selects a carrier M wave superior in quality. When the code error is contained, data transmitted by the carrier of good quality is preserved in a received data memory 21. A carrier number receiving data transmitted by the carrier of inferior quality is managed by a re-transmission control part 20. A retransmission request signal containing the carrier number is transmitted to a transmission device from a control information transmission part 22 by the carrier of good quality, which the use carrier decision part 18 decides. When received data is retransmission data, a series of new data are detected in a code error detection part 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a multi-carrier transmission system for transmitting a plurality of N data in parallel by using a plurality of N carriers having different frequencies. The present invention relates to an error compensation technique for compensating for a code error of data generated on a transmission path by retransmission.

[0002]

2. Description of the Related Art In a multicarrier transmission type transmitting apparatus, a plurality of N-wave carriers having different frequencies are modulated by a plurality of N different data and transmitted simultaneously. A multi-carrier transmission receiving apparatus simultaneously receives and combines a plurality of data transmitted using the plurality of carriers.

A method for compensating for a transmission data code error in such a conventional multicarrier transmission system will be described. The transmitting device adds a code error detection code and a sequence number for managing the order of data to the data for each carrier and transmits the data. Performs error detection, saves data for which no code error was detected in the data memory of the receiving device, and transmits a retransmission request signal including a sequence number for data where a code error was detected, regardless of carrier quality. The transmission device transmits the retransmission data to the carrier that transmitted the data in which no code error was detected, based on the retransmission request signal.

The above is described in the reference (Atarashi, H. et a
l., "Partial Frequency ARQ System for Multi-Carrier
Packet Communication ", IEICE TRANS.COMMUN., Vol.E78-
B, August 1995).

[0005] A conventional transmitting apparatus and receiving apparatus of the multicarrier transmission system will be described with reference to FIGS. 7 and 8.
FIG. 7 is a block diagram of a conventional transmitting apparatus. FIG. 8 is a block diagram of a conventional receiving apparatus. In the transmitting apparatus T shown in FIG. 7, a code error detection code adding section 40 adds a code error detection code to each of the carriers to the input transmission data. Also, in preparation for retransmission, the transmission data is stored in the transmission data memory 12, and the data is transmitted by the multicarrier data transmission unit 15.

In the case of retransmission, the control information sent from the receiving device is received by the control information receiving unit 13, and the data to be retransmitted is read from the transmission data memory 12 by the transmission control unit 41 based on the control information. The retransmission data is transmitted by the multicarrier data transmission unit 15. In this case, data transmitted by a carrier in which a code error is detected is retransmitted by a carrier in which a code error is not detected.

In the receiving apparatus R shown in FIG. 8, transmission data is received by a multi-carrier data receiving section 16, and a code error detection section 19 detects a code error of the transmission data for each carrier. Is discarded, and data in which no code error is detected is stored in the transmission data memory 12. The retransmission control unit 20 manages the sequence numbers of the data in which the code error is detected and the data in which the code error is not detected, and the control information transmitting unit 22 transmits a retransmission request signal including the sequence numbers.

[0008]

In such a conventional transmission technique using multicarriers, data sequence management for each carrier is indispensable, and the complexity of the management increases the circuit scale and the sequence. A problem arises in that the transmission efficiency is reduced by adding the number information bits to each data of each carrier.

Further, it is necessary to detect a code error for data transmitted by each carrier, and a large number of code error detection code bits are added, thereby deteriorating transmission efficiency. If the frequency of adding the code error detection code to the transmission data is reduced, the time required for code error compensation such as retransmission is long, resulting in a problem that transmission delay increases.

An object of the present invention is to provide an error compensation method and a multi-carrier transmission apparatus which can eliminate the sequence management of data for each carrier. I do. SUMMARY OF THE INVENTION An object of the present invention is to provide an error compensation method and a multi-carrier transmission apparatus that do not need to add a code error detection code to each data of each carrier. The present invention
An object of the present invention is to provide an error compensation method and a multi-carrier transmission device with a small transmission delay. An object of the present invention is to provide an error compensation method and a multi-carrier transmission device with high transmission efficiency.

[0011]

The present invention measures the carrier quality on the receiving side and, when a code error occurs on the transmission line, estimates the location of the occurrence based on the quality of the measured carrier. The most important feature.

That is, data transmitted using a carrier that satisfies a predetermined quality is treated as having no code error, and any of data transmitted using a carrier that does not satisfy a predetermined quality contains a code error. Retransmission control is performed based on the determination that the

Thus, it is not necessary to detect a code error for each data, but only to detect the presence or absence of a code error for a plurality of N pieces of data transmitted in parallel. There is no need to add a code error detection code. As a result, the circuit scale of the code error detection means can be made smaller than before, and the bit length of the code error detection code can be made shorter than before. Also, for retransmission control, it is not necessary to perform data sequence management for each carrier and other complicated controls, so that the circuit scale can be reduced.

That is, a first aspect of the present invention is to sort a series of data into a plurality of N data and transmit the plurality of N data in parallel using a plurality of N-wave carriers having different frequencies. This is an error compensation method for compensating for a code error of data in the transmission path. A feature of the present invention is that, on the receiving side, the quality of each of the plurality of N-wave carriers is measured, and a series of the plurality of N data transmitted using the plurality of N-wave carriers is measured. Detects code errors in the entire data,
When a code error is detected in the series of data, M (M <M <) satisfying a predetermined quality among the plurality of N-wave carriers.
N) The carrier of the wave is selected, and the data transmitted using the carrier of the M wave is stored in the data memory on the receiving side assuming that there is no code error, and the other predetermined quality is not satisfied (N- M) For data transmitted using the carrier of the wave, a retransmission request is sent to the transmission side using the carrier of the M wave.

Preferably, the retransmission request includes carrier number information of an (NM) wave that does not satisfy a predetermined quality when the data requesting retransmission is transmitted.

[0016] The transmitting side, based on the retransmission request signal,
Data transmitted on a (NM) wave carrier that does not satisfy the predetermined quality can be retransmitted on the M wave carrier. Alternatively, based on the retransmission request signal, the transmitting side uses the (NM) wave carrier and the (NM) wave carrier to transmit data transmitted on the (NM) wave carrier that does not satisfy the predetermined quality. The data transmitted on the carrier of the (NM) wave that does not satisfy the predetermined quality may be overlapped and retransmitted using a plurality of carriers having low correlation with each other. In this case, the receiving side can perform selection diversity. Here, (N−M) ≦ M. The quality can be determined by the reception level of the carrier.

A second aspect of the present invention is a multicarrier transmission apparatus, which divides a series of data into a plurality of N data, and divides the plurality of N data using a plurality of N-wave carriers having different frequencies. A transmitting device having a means for transmitting the data to a plurality of N-wave carriers, a means for receiving a multi-carrier signal transmitted in parallel using the plurality of N-wave carriers, and synthesizing the multi-carrier signal into the series of data. And a receiving device including means for requesting the transmitting device to retransmit the data.

Here, it is a feature of the present invention that the receiving apparatus includes: means for measuring the quality of each of the plurality of N-wave carriers; and the means for transmitting the plurality of N-wave carriers using the plurality of N-wave carriers. Means for detecting a code error in the entire series of data consisting of a plurality of N data, and when a code error is detected in the series of data by the detection means, a predetermined quality of the plurality of N-wave carriers is determined. Means for selecting an M (M <N) wave carrier that satisfies the above condition, and the other means that does not satisfy the predetermined quality (N−
M) means for transmitting a retransmission request signal to the transmitting device using the M-wave carrier for data transmitted using the M-wave carrier.

The retransmission request signal does not satisfy the predetermined quality at the time when the data requesting retransmission is transmitted (NM).
It is desirable to include wave carrier number information.

[0020] The transmission device may include means for adding one code error detection code to the entire series of data.

[0021] The transmitting apparatus may include means for retransmitting, on the basis of the retransmission request signal, data transmitted on the (NM) wave carrier that does not satisfy the predetermined quality by the M wave carrier. . Alternatively, in the transmitting device, based on the retransmission request signal, the retransmission means,
Based on the retransmission request signal, data transmitted on the (NM) wave carrier that does not satisfy the predetermined quality is retransmitted by using the M wave carrier and the (NM) wave carrier, respectively. Or a means for retransmitting data transmitted on carriers of the (NM) wave less than the predetermined quality by using a plurality of carriers having low correlation with each other. You can also. Here, (N−M) ≦ M. The quality can be determined by the reception level of the carrier.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram of a transmitting apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram of the receiving apparatus according to the embodiment of the present invention.

The present invention relates to a multicarrier transmission apparatus, as shown in FIG. 1, which divides a series of data into a plurality of N data and uses the N data carriers each having a different frequency. 2. A transmitting apparatus T having a multi-carrier data transmitting section 15 for transmitting data in parallel, and as shown in FIG. 2, receiving a multi-carrier signal transmitted in parallel using the plurality of N-wave carriers, and A multi-carrier data receiving unit 16 comprising a multi-carrier data receiving unit 16 and a re-transmission control unit 20 for requesting the transmitting device T to re-transmit the data when the data contains a code error. It is a transmission device.

Here, a feature of the present invention is that the receiving apparatus R comprises: a carrier signal quality measuring unit 17 for measuring the quality of each of the plurality of N-wave carriers;
The plurality N transmitted using the plurality of N-wave carriers
And a code error detecting unit 19 for detecting a code error in the entire series of data consisting of a plurality of data. When the code error detecting unit 19 detects a code error in the series of data, And a used carrier determining unit 18 for selecting a carrier of an M (M <N) wave that satisfies a predetermined quality among the above, and a retransmission control unit 20 controls the carrier of another (NM) wave that does not satisfy the predetermined quality. Is to send a retransmission request signal to the transmitting apparatus T using the M-wave carrier.

[0025] The retransmission request signal does not satisfy the predetermined quality at the time when the data requesting retransmission is transmitted (NM).
Contains wave carrier number information.

The transmitting apparatus T includes a code error detection code adding section 11 for adding one code error detection code to the whole series of data, and the predetermined quality (N- M) a transmission control / carrier designation unit 14 for retransmitting data transmitted on the carrier of the M wave by the carrier of the M wave.

Based on the retransmission request signal, the transmission control / carrier designation section 14 does not satisfy the predetermined quality (N
-M) the data transmitted on the wave carrier can be retransmitted in an overlapping manner using the M wave carrier and the (NM) wave carrier, respectively, or based on the retransmission request signal, The predetermined quality is not satisfied (N
-M) It is also possible to retransmit data transmitted on a wave carrier using a plurality of carriers having low correlation with each other. Here, (N−M) ≦ M. The quality is determined by the reception level of the carrier.

[0028]

【Example】

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS. 1 and 2 are as described above. FIG. 3 is a flowchart showing the operation of the transmitting apparatus T according to the embodiment of the present invention. FIG. 4 is a flowchart showing the operation of the receiving apparatus R according to the embodiment of the present invention. FIG. 5 is a diagram for explaining the relationship between carriers and data according to the first embodiment of the present invention.

The operation of the transmitting apparatus T according to the first embodiment of the present invention will be described with reference to FIG. As shown in FIG.
Receives the control signal from the receiving device R by the control information receiving unit 13. It is determined whether the control signal is a retransmission request signal (S10). If the control signal is not a retransmission request signal, the code error detection code adding unit 11 adds a code error detection code to the new data (S11). The new data is distributed to the multicarrier (S12). At this time, in the present invention, it is not necessary to add the code error detection code to each data allocated to the multicarrier, but only to add one to a series of new data. Further, the code error detecting code adding unit 11 stores a copy of the new data in the transmission data memory 12 in case of retransmission (S
13). The new data allocated to the multicarrier is transmitted by the multicarrier data transmitting unit 15 to the receiving device R by the multicarrier. When the control information receiving unit 13 receives the retransmission request signal (S1
0), the transmission control / carrier designation unit 14 reads the retransmission data from the transmission data memory 12 (S14), and transmits the data by multicarrier via the multicarrier data transmission unit 15 (S15).

The operation of the receiving apparatus R according to the first embodiment of the present invention will be described with reference to FIG. As shown in FIG.
The carrier signal quality measuring unit 17 measures the quality of the carrier that carries the data received by the multicarrier data receiving unit 16 (S16). The multicarrier data receiving unit 16 determines whether the received data is retransmission data (S17). If the received data is not retransmission data, the code error detection unit 19 detects a code error of the data (S1).
8). At this time, according to the present invention, it is not necessary to detect a code error for each data allocated to the multicarrier, and it is sufficient to detect a code error for a combination of each data transmitted by the multicarrier into a series of data. If no code error is detected, the code error detection unit 19
The received data is stored in the received data memory 21 (S1
9). At this time, if a code error is detected, the code error detection unit 19 stores the data transmitted on the high quality carrier in the reception data memory 21 (S2).
0), the data transmitted on the poor quality carrier is notified to the retransmission control unit 20; The retransmission control unit 20 issues a retransmission request to the transmitting device T according to this notification (S2
1). The control information transmitting unit 22 generates a retransmission request signal according to the retransmission request, and transmits the retransmission request signal to the transmitting device T as a control signal (S24).

If the received data is retransmitted data, the code error detecting section 19 first reads out data transmitted on a high quality carrier from the received data memory 21 (S22) and combines the data with the retransmitted data. The data is synthesized into a series of data and its code error is detected (S18).

That is, the data input to the transmitting apparatus T is added with one code error detection code by the code error detection code adding section 11 before being allocated to the multicarrier, and the transmission data is prepared for retransmission of data. Stored in the memory 12. The control information sent from the receiving device R is received by the control information receiving unit 13. The retransmission data is read from the transmission data memory 12 by the transmission control / carrier specifying unit 14, and a carrier for transmitting the retransmission data is specified. The data and the retransmission data are transmitted by the multicarrier data transmission unit 15.

At this time, as shown in FIG. 5, when the total number of carriers is "4" and the number of high quality carriers to be selected is "2", the transmission control / carrier designating section 14 Carriers 1 and 3 are selected as good carriers (S50), and data 2 and data 4 transmitted on the carrier of lower quality are combined with carrier 1 and carrier 3 of a set of carriers of higher quality and carrier of lower quality. Is retransmitted by the set of carrier 2 and carrier 4 (S51).

The data transmitted from the transmitting apparatus T in this manner is received by the multi-carrier data receiving section 16, the carrier quality is measured by the carrier signal quality measuring section 17, and the carrier quality is determined by the used carrier determining section 18. The selected carrier M wave is selected.

If the data received by the multicarrier data receiving section 16 is new data, a code error is detected by the code error detecting section 19. At this time, according to the present invention, a code error is detected in a case where each data that has been distributed to the multicarrier is combined with a series of new data. If no code error is included, all received data is stored in the received data memory 21. When a code error is included, data transmitted on a high-quality carrier is stored in the reception data memory 21, and data transmitted on a low-quality carrier is retransmitted by the retransmission control unit 20. The received carrier number is managed, and the used carrier determining unit 18 is used.
The retransmission request signal including the carrier number is transmitted to the transmitting apparatus T by multi-carrier transmission by the control information transmitting unit 22 using a carrier of good quality determined by the above.

If the data received by the multi-carrier data receiving unit 16 is retransmission data, the data that has been transmitted on a high-quality carrier and stored in the reception data memory 21 is read out from the reception data memory 21,
The data is combined with the retransmission data to form a series of new data, and a code error is detected by the code error detector 19 for this data.

At this time, the code error detecting section 19
Since the same data 2 and 4 are transmitted using both good quality carriers 1 and 3 and poor quality carriers 2 and 4, as shown in FIG. It can be carried out.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a diagram for explaining the relationship between carriers and data according to the second embodiment of the present invention. In the second embodiment of the present invention, as shown in FIG. 6, when the total number of carriers is "4" and the number of high quality carriers to be selected is "2", the carriers having good quality at the time of reception are determined as carriers. When 1 and 3 are selected (S52), the data 2 and 4 transmitted by the carriers 2 and 4 of the lower quality
Irrespective of the carrier quality, a combination of carriers having a low correlation (for example, a set of carrier 1 and carrier 3 and a set of carrier 2 and carrier 4 separated by frequency intervals) is determined in advance, and carrier 1 and carrier 3 are used. Data 2 is retransmitted, and data 4 is retransmitted using carrier 2 and carrier 4 (S53).

As described above, the same data 2 and 4 are transmitted using both the pair of carrier 1 and carrier 3 and the pair of carrier 2 and carrier 4 having low correlation with each other. , Diversity reception for selecting one without a code error can be performed.

[0040]

As described above, according to the present invention,
It is not necessary to manage the sequence of each data for each carrier, and it is not necessary to add a code error detection code to each data for each carrier, and it is possible to reduce redundant bits and improve transmission efficiency. Can be.
Further, by transmitting the control information on a carrier having excellent quality, the probability of erroneous control information can be reduced as compared with the conventional technology, and the number of retransmissions can be reduced.
Transmission delay can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a transmitting apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram of a receiving apparatus according to the embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of the transmitting apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the receiving apparatus according to the embodiment of the present invention.

FIG. 5 is a diagram for explaining a relationship between carriers and data according to the first embodiment of the present invention.

FIG. 6 is a diagram for explaining the relationship between carriers and data according to the second embodiment of the present invention.

FIG. 7 is a block diagram of a conventional transmitting apparatus.

FIG. 8 is a block diagram of a conventional receiving apparatus.

[Explanation of symbols]

 11, 40 Code error detection code addition unit 12 Transmission data memory 13 Control information reception unit 14 Transmission control / carrier designation unit 15 Multicarrier data transmission unit 16 Multicarrier data reception unit 17 Carrier signal quality measurement unit 18 Used carrier determination unit 19 Code Error detection unit 20 Retransmission control unit 21 Receive data memory 22 Control information transmission unit 41 Transmission control unit T Transmission device R Receiving device

Claims (13)

[Claims] A series of data is divided into a plurality of N data, the plurality of N data are transmitted in parallel using a plurality of N-wave carriers having different frequencies, and a code error of data in a transmission path is detected. In the error compensation method for compensating, on the receiving side, the quality of each of the plurality of N-wave carriers is measured, and a series of data consisting of the plurality of N data transmitted using the plurality of N-wave carriers is measured. A code error is detected for the entire data, and when a code error is detected in the series of data, an M (M <N) wave carrier that satisfies a predetermined quality is selected from the plurality of N waves, and the M wave is selected. The data transmitted using the carrier is stored in the data memory of the receiving side assuming that there is no code error, and the other predetermined quality is not satisfied (N- Error compensating method characterized by sending a retransmission request using the carrier of the M-wave to the transmission side for) data transmitted with a wave of the carrier. 2. The error compensation method according to claim 1, wherein the retransmission request includes carrier number information of an (NM) wave that does not satisfy a predetermined quality when data requesting retransmission is transmitted. 3. The error according to claim 1, wherein the transmitting side retransmits data transmitted on a (NM) wave carrier that does not satisfy the predetermined quality on the M wave carrier based on the retransmission request signal. Compensation method. Where (N−M) ≦ M 4. The transmission side, based on the retransmission request signal, transmits data transmitted on a (NM) wave carrier that does not satisfy the predetermined quality to the M wave carrier and the (N
2. The error compensation method according to claim 1, wherein: -M) retransmission is performed by using a carrier of a wave. However, (N−M) ≦
M 5. The transmission side, based on the retransmission request signal, overlaps data transmitted on carriers of (NM) waves that do not satisfy the predetermined quality using a plurality of carriers having low correlation with each other. The error compensation method according to claim 1, wherein retransmission is performed. Where (N−M) ≦ M 6. The error compensation method according to claim 1, wherein said quality is determined by a reception level of a carrier. 7. A transmitting device comprising means for sorting a series of data into a plurality of N data and transmitting the plurality of N data in parallel by using a plurality of N-wave carriers having different frequencies, respectively. Means for receiving a multi-carrier signal transmitted in parallel using a carrier of a wave and synthesizing the series of data, and when the data includes a code error, a means for requesting the transmitting apparatus to retransmit the data. A multi-carrier transmission apparatus comprising: a reception device comprising: a reception unit configured to measure quality of each of the plurality of N-wave carriers; and The plurality N
Means for detecting a code error with respect to the entire series of data consisting of a plurality of data; and when a code error is detected in the series of data by the detection means, a predetermined quality among the plurality of N-wave carriers is satisfied. Means for selecting the carrier of the M (M <N) wave, and retransmitting the data transmitted using the carrier of the (NM) wave that does not satisfy the predetermined quality by using the carrier of the M wave Means for transmitting a request signal to the transmission device. 8. The retransmission request signal does not satisfy a predetermined quality at the time of transmitting data requesting retransmission (N-
The multi-carrier transmission apparatus according to claim 7, wherein M) includes carrier number information of a wave. 9. The multicarrier transmission apparatus according to claim 7, wherein said transmission apparatus includes means for adding one code error detection code to the entire series of data. 10. The transmission apparatus further includes means for retransmitting, on the basis of the retransmission request signal, data transmitted on a (NM) wave carrier that does not satisfy the predetermined quality using the M wave carrier. Item 8. The multicarrier transmission device according to item 7. Where (N−M) ≦ M 11. The transmitting apparatus transmits, based on the retransmission request signal, data transmitted on a (NM) wave carrier that does not satisfy the predetermined quality to the M wave carrier and the (NM) wave carrier. 8. The multicarrier transmission apparatus according to claim 7, further comprising means for retransmitting the waves by using the carriers of the waves. Where (N−M) ≦ M 12. The transmitting apparatus, based on the retransmission request signal, duplicates data transmitted on carriers of (NM) waves that do not satisfy the predetermined quality using a plurality of carriers having low correlation with each other. 8. The multi-carrier transmission apparatus according to claim 7, further comprising means for causing retransmission. However, (N-
M) ≦ M 13. The multicarrier transmission apparatus according to claim 7, wherein said quality is determined by a reception level of a carrier.