JP2003078480A - Mobile communication system and method, base station, mobile station and method for transmitting signal in mobile communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve throughput by reducing repeating of a retransmission request from a mobile station. SOLUTION: A mobile station measures receiving qualities of respective signals from a first antenna and a second antenna of a base station (S3, S5), stores the results of the measurement, and requests the base station to retransmit a signal from an antenna with a higher receiving quality, based on the stored measurement results, when an error is detected in received data thereafter (S10, S11, S12). The base station retransmits the data, using the antenna with the higher receiving quality (i.e., a base station antenna to yield the higher receiving quality at the mobile station) (S15). In another aspect, the mobile station measures a receiving quality of a signal and notifies the base station of the receiving quality. The base station selects a radio channel adapted to a receiving quality on the basis of the measurement result and transmits a signal, using the radio channel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication system, a mobile communication method, a base station and a mobile station, and more particularly to a mobile station and a base station having a plurality of antennas. A mobile communication system that performs signal transmission / reception control including signal retransmission control by a base station based on an automatic retransmission request from a mobile station, a mobile communication method executed in the mobile communication system, and the mobile communication system. The present invention relates to a base station and a mobile station which are configured.

The present invention also relates to a signal transmission method and system in a mobile communication system, and more specifically, in a mobile communication system that transmits and receives signals while making an automatic retransmission request, improves reception quality in a mobile station. The present invention relates to a signal transmission method and system for changing a channel and transmitting a signal.

Further, the present invention relates to a base station which communicates according to such a signal transmitting method. The present invention also relates to a mobile station that performs communication according to the signal transmission method.

[0004]

2. Description of the Related Art FIG. 13 shows a conventional mobile communication system 1.
0 is a block configuration diagram, and FIG. 14 is a diagram for explaining the cooperative operation of the mobile communication system in the conventional automatic retransmission request. In the base station 1, data addressed to the mobile station 11 inputted from the data input terminal 6 is transmitted by ARQ (Automatic Repeat R).
equest) Input to the processor 2. In the ARQ processor 2,
CRC (Cyclic) to detect errors that occur during transmission
The data is stored after adding error-detectable parity such as Redundancy Checking (A1 in FIG. 14).
It is also output to the transmitter 3. The transmitter 3 modulates the input data into a transmission signal, and then transmits the transmission signal from the base station first antenna 7 via the transmission / reception duplexer 4 to the mobile station 11 via the downlink 22 (A2).

In the mobile station 11, the signal from the mobile station antenna 17 is input to the receiver 12 via the transmission / reception duplexer 16. Then, the signal received by the receiver 12 is input to the ARQ processor 13 as received data (A3). The ARQ processor 13 detects an error using the CRC (A4).

If no error is detected in the received data, the ARQ processor 13 outputs the received data to the data output terminal 1.
4 and outputs confirmation of arrival of the received data to the transmitter 15. The transmitter 15 confirms arrival of the received data via the uplink 21 by the ARQ processor 2 of the base station 1.
(A5). And A who received the notification of arrival confirmation
The RQ processor 2 deletes the data stored for retransmission (A7 and A8).

On the other hand, when an error is detected in the received data in A4, the ARQ processor 13 notifies the ARQ processor 2 of the base station 1 of the retransmission request of the received data via the uplink 21 (A6). And the ARQ that received the notification of the retransmission request
The processor 2 transmits the requested data to the base station first antenna 7
To retransmit (A7 and A9).

Further, FIGS. 15 and 16 are flowcharts for explaining the configuration and operation of a conventional mobile communication system. As shown in FIG. 15, the conventional mobile communication system includes a base station 21 and a mobile station 31.

The base station 21 uses ARQ (Automatic Repeat).
(Request) processor 22, transceiver 23, signal input terminal 24, and base station antenna 25.
One mobile station 31 includes a transceiver 32 and an ARQ processor 3
3, a signal output terminal 34, and a mobile station antenna 35.

The operation of the conventional mobile communication system will be described below with reference to the flowchart of FIG. In the base station 21, the mobile station 31 input from the signal input terminal 24
The addressed signal is input to the ARQ processor 22. The ARQ processor 22 is provided with C so that it can detect errors that occur during transmission.
After adding error-detectable parity such as RC (Cyclic Redundancy Checking), the signal is stored (B1) and output to the transceiver 23. The transceiver 23 notifies the mobile station of the start of signal transmission (B2), and then transmits the signal to the mobile station 31 via the downlink 42 which is a frequency channel determined for signal transmission to the mobile station. Send (B3).

In the mobile station 31, the signal of the downlink 42 received by the mobile station antenna 35 is received by the transceiver 32 (B
After 4), it is input to the ARQ processor 33. The ARQ processor 33 performs error detection on the received signal using CRC. When no error is detected in the received signal (NO in B5), the received signal is output from the signal output terminal 34, and the arrival confirmation of the received signal is confirmed via the uplink 41 by the ARQ processor 22 of the base station. (B6).
After that, the ARQ processor 22 that receives the arrival confirmation
The signal stored for retransmission is deleted (N in B8
O, and B9).

On the other hand, when an error is detected in the received signal (YES in B5), the ARQ processor 33 notifies the retransmission request of the received signal to the ARQ processor 22 of the base station via the uplink 41 (B7). To do. Then, the ARQ processor 22 that received the notification of the retransmission request retransmits the requested signal on the frequency channel used for the transmission (YES in B8,
And B10).

[0013]

However, as shown in FIG.
And in the method of transmitting a high quality signal with an automatic retransmission request in the conventional mobile communication system described with reference to FIG. 14, since the same base station antenna is always used for transmission,
In a simple mobile station that cannot achieve receive antenna diversity or in a mobile station that stays in the same place for a long time, the low reception quality state is continued due to the effects of fading or shadowing, and repeat requests are repeated, resulting in a decrease in throughput. There was a problem.

Further, as described with reference to FIGS. 15 and 16, in the conventional mobile communication system, the base station is
Fading or shadowing effects on a simple mobile station that cannot achieve receive antenna diversity, or on a mobile station that has a long potential at the same location, because it transmits only on the determined frequency channel for signal transmission to the mobile station. As a result, there is a problem that the reception quality remains low, the retransmission request is repeated, and the throughput decreases.

Therefore, an object of the present invention is to reduce the number of repeat requests for retransmission from mobile stations and improve throughput.

[0016]

In order to solve the above-mentioned problems, a mobile communication system according to the present invention comprises a mobile station and a base station as set forth in claim 1, wherein the mobile station is In a mobile communication system that transmits and receives a signal while making an automatic retransmission request to a base station, the mobile station includes reception quality measuring means for measuring the reception quality of a radio signal transmitted from the base station, and the reception quality measuring means. Request transmitting means for transmitting to the base station a radio resource use request for requesting the use of a radio resource adapted to the reception quality based on the reception quality of the radio signal. The base station is directed to the mobile station including a request receiving unit that receives the wireless resource use request, and a signal that is requested to be retransmitted by the automatic retransmission request using the wireless resource requested by the wireless resource use request. And a signal transmitting means for transmitting a signal.

Further, in the mobile communication system according to the second aspect, the signal transmitting means transmits signals by using radio resources in the order of the number of retransmission requests from the mobile station.

Further, in the mobile communication system according to claim 3, the reception quality is the reception power, or (Equation 1) C / (I + N) C: carrier power I: interference power N: noise power or (Equation) 2) S / (I + N) S: Signal power I: Interference power N: Noise power or (Equation 3) C / N C: Carrier power N: Noise power (Equation 4) S / N S: Signal power N: Noise power Or, the error rate, or the likelihood obtained at the time of error decoding, or the base station transmission power value, or the increase or attenuation amount of the base station transmission power, or the correlation value obtained by despreading the spreading code,
Alternatively, a combination of these is used.

Further, in the mobile communication system according to claim 4, as the radio resource, at least one antenna, directivity of at least one antenna, a radio channel, a transmission path, or a combination thereof is used. It is characterized by that. Here, the antenna may be single or plural, and when using a plurality of antennas, the directivity of each antenna may be different. Further, the transmission route is assumed to be a case where a signal is indirectly transmitted via a mobile station as a relay station (multi-hop connection).

A mobile communication system according to the present invention comprises a mobile station and a base station having a plurality of antennas, as in claim 5, and is a base station based on an automatic retransmission request from the mobile station. In the mobile communication system for performing signal transmission / reception control including signal retransmission control by the mobile station, the mobile station measures quality of reception of signals transmitted from a plurality of antennas of the base station, and Request transmitting means for transmitting to the base station an antenna use request for requesting transmission of a signal from at least one antenna of the plurality of antennas, based on the acquired reception quality of the signal from each antenna. And a request receiving unit that receives an antenna use request to request transmission of a signal from at least one antenna of the plurality of antennas, From the antenna requested by the antenna use request, it is characterized by and a signal transmitting means for transmitting a signal addressed to the mobile station containing the requested signal retransmission by the ARQ.

Further, the mobile communication method according to the present invention is executed in a mobile communication system including a mobile station and a base station having a plurality of antennas, as in claim 11. A mobile communication method for performing signal transmission / reception control including signal resending control by a base station based on an automatic resending request from a mobile station, wherein the mobile station, of a signal transmitted from a plurality of antennas of the base station A quality measurement step of measuring reception quality, and transmission of a signal from at least one antenna of the plurality of antennas based on the reception quality of the signal from each antenna acquired by the measurement in the mobile station. Request transmission step of transmitting to the base station an antenna use request for requesting the request, and requesting the base station to transmit a signal from at least one antenna of the plurality of antennas. Request receiving step of receiving the antenna use request of the above, and the base station transmits a signal addressed to the mobile station from the antenna requested by the antenna use request, including a signal requested to be retransmitted by the automatic retransmission request. And a signal transmitting step for performing the same.

Further, a base station according to the present invention is defined in claim 17.
As described above, a mobile station including a plurality of antennas, a mobile station that requests transmission of a signal from at least one of the plurality of antennas based on the reception quality of signals transmitted from the plurality of antennas, and a mobile body A base station which configures a communication system and performs signal transmission / reception control including signal retransmission control based on an automatic retransmission request from the mobile station, with at least one of the plurality of antennas. Request receiving means for receiving an antenna use request to request transmission of a signal from one antenna, and the mobile station including a signal requested to be retransmitted by the automatic retransmission request from the antenna requested by the antenna use request And a signal transmitting means for transmitting a signal addressed thereto.

A mobile station according to the present invention is a mobile station according to claim 21.
As described above, including the retransmission control of the signal based on the automatic retransmission request with the base station that includes the plurality of antennas and transmits the signal based on the signal transmission request from at least one of the plurality of antennas. A mobile station that performs signal transmission / reception control, based on quality measurement means for measuring reception quality of signals transmitted from a plurality of antennas of the base station, and reception quality of signals from each antenna acquired by measurement. Request transmitting means for transmitting to the base station an antenna use request for requesting transmission of a signal from at least one of the plurality of antennas.

The mobile communication system, the mobile communication method, the base station and the mobile station according to the present invention are based on the same technical idea. Captured, captured from mobile communication methods, captured from base stations, captured from mobile stations.

Therefore, the problem solving means by the mobile communication system according to the present invention will be described below, but the problem solving means for the mobile communication method, the base station and the mobile station are also based on the same technical idea. is there.

In the mobile communication system according to the present invention, the quality measuring means in the mobile station measures the reception quality of the signals transmitted from the plurality of antennas of the base station, and the request transmitting means obtains each of the obtained values. Based on the reception quality of the signal from the antenna, an antenna use request for requesting the transmission of the signal from at least one of the plurality of antennas is transmitted to the base station. That is, the request transmitting means transmits to the base station an antenna use request to the effect that the base station requests the signal transmission from at least one antenna whose reception quality of the signal was better than that of the other antennas.

In the base station, when the request receiving means receives the antenna use request from the mobile station, the signal transmitting means causes the antenna requested by the antenna use request to retransmit the signal requested by the automatic retransmit request. And transmits a signal addressed to the mobile station.

As a result, based on the reception quality of the signal measured by the mobile station, the signal addressed to the mobile station is transmitted from at least one antenna of the base station whose reception quality is relatively good. To be done. Therefore, the reception quality of the signal at the mobile station is improved. By this means, it is possible to prevent repeated requests for retransmission from the mobile station and improve throughput.

The above mobile communication system can also be applied to the transmission of multicast signals addressed to a plurality of mobile stations. That is, in the mobile communication system according to claim 6, the quality measuring means in the mobile station measures the reception quality of the signal transmitted from the plurality of antennas of the base station, and the request transmitting means obtains the measurement. Based on the reception quality of the signal from each antenna, an antenna use request for requesting the transmission of the multicast signal from at least one of the plurality of antennas is transmitted to the base station. That is, the request transmitting means transmits to the base station an antenna use request to the effect that the base station requests the multicast signal to be transmitted from at least one antenna whose signal reception quality was better than other antennas. .

In the base station, when the request receiving means receives the antenna use request from the mobile station, the multicast signal transmitting means is requested to retransmit by the automatic retransmit request from the antenna requested by the antenna use request. A multicast signal including the multicast signal addressed to the mobile station is transmitted.

As a result, the multicast signal addressed to the mobile station is transmitted from at least one antenna whose reception quality is relatively good, based on the reception quality of the signal measured by the mobile station. It is possible to improve the reception quality of the multicast signal at the mobile station, prevent repeated retransmission requests from the mobile station, and improve throughput.

However, in the above case, there may be a case in which the antenna use requests from a plurality of mobile stations exist over a plurality of antennas. However, as in claim 7, the multicast signal transmitting means uses the antenna use requests from a plurality of mobile stations. But,
If there are multiple antennas, if the configuration is such that the multicast signals are transmitted using the antennas in descending order of the number of requests, the overall system will improve the reception quality of the multicast signals in more mobile stations and improve the overall reception. It is possible to reduce the number of unnecessary retransmission requests and improve the throughput of the entire system.

The inventions of claims 6 and 7 can be described as follows from the viewpoint of the mobile communication method, the base station and the mobile station. That is, the mobile communication method according to claim 12 is executed in a mobile communication system configured to include a plurality of mobile stations and a base station having a plurality of antennas, and an automatic retransmission request from the mobile station is made. A mobile communication method for performing signal transmission / reception control including signal retransmission control by a base station according to, wherein the mobile station measures quality of reception of signals transmitted from a plurality of antennas of the base station. And an antenna for requesting transmission of a multicast signal from at least one of the plurality of antennas based on the reception quality of the signal from each antenna acquired by the measurement in the mobile station. Request transmission step of transmitting a usage request to the base station, and transmission of a multicast signal from the at least one antenna of the plurality of antennas at the base station A request receiving step of receiving an antenna use request to the effect that the request is made, and the base station addressed to the mobile station including the multicast signal requested to be retransmitted by the automatic retransmit request from the antenna requested by the antenna use request. And a multicast signal transmitting step of transmitting the multicast signal.

A mobile communication method according to a thirteenth aspect is the mobile communication method according to the twelfth aspect, wherein in the multicast signal transmitting step, antenna use requests from a plurality of mobile stations are present over a plurality of antennas. The base station is characterized in that the base station transmits a multicast signal using an antenna in descending order of the number of requests.

The base station according to claim 18 is provided with a plurality of antennas, and a multicast signal is transmitted from at least one of the plurality of antennas based on the reception quality of the signals transmitted from the plurality of antennas. In a base station that configures a mobile communication system together with a plurality of mobile stations requesting, and performs signal transmission / reception control including retransmission control of a multicast signal based on an automatic retransmission request from the mobile station, with the mobile station. A request receiving means for receiving an antenna use request for requesting transmission of a multicast signal from at least one of the plurality of antennas; and the automatic retransmission from the antenna requested by the antenna use request. Send a multicast signal addressed to the mobile station, including the multicast signal requested to be retransmitted by the request And multicast signal transmitting means that,
It is characterized by having.

Further, in the base station according to claim 19, in the base station according to claim 18, when the request for antenna use from a plurality of mobile stations exists over a plurality of antennas, the number of requests is large. It is characterized by transmitting multicast signals using antennas in sequence.

A mobile station according to a twenty-second aspect is provided with a plurality of antennas and automatically retransmits with a base station which transmits a multicast signal based on a signal transmission request from at least one of the plurality of antennas. A mobile station that performs signal transmission / reception control including retransmission control of a multicast signal based on a request, quality measuring means for measuring reception quality of signals transmitted from a plurality of antennas of the base station, and each obtained by the measurement. Request transmitting means for transmitting to the base station an antenna use request for requesting transmission of a multicast signal from at least one of the plurality of antennas based on reception quality of a signal from the antenna. It is characterized by that.

In the mobile communication system according to claim 5 or 6, as in claim 8, the request receiving means of the base station, when receiving the antenna use request, performs antenna reception by the diversity system. It is desirable to configure it to do so. Diversity has multiple antennas,
There are three methods: a selective combining method using a signal from the antenna with the maximum level, an equal gain combining method of adding a plurality of antenna outputs as they are, and a maximum ratio combining method of weighting and adding according to the level. The request receiving means of the base station may use any method. By performing antenna reception by these diversity methods, stable reception of an antenna use request can be realized.

Similarly, in the mobile communication method according to claim 14, in the mobile communication method according to claim 11 or 12, in the request receiving step, the base station receives the antenna use request. It is characterized by performing antenna reception by the diversity method. Further, a base station according to a twentieth aspect is characterized in that, in the base station according to the seventeenth aspect or the eighteenth aspect, when the request receiving means receives the antenna use request, antenna reception is performed by a diversity method.

Further, in the mobile communication system according to any one of claims 5 to 8, when the quality measuring means in the mobile station measures the reception quality of the signals transmitted from the plurality of antennas of the base station. The signal to be measured is not limited to a specific signal, and various signals can be used. Specifically, as in claim 9, the quality measuring means is a synchronization signal transmitted from at least one antenna of the base station, a signal of broadcast information, an individual signal to the mobile station, a multicast signal, or these. Among these, the reception quality can be measured by using a combination of two or more.

Similarly, in the mobile communication method according to claim 15, in the mobile communication method according to any one of claims 11 to 14, the mobile station in the quality measuring step is at least the base station. It is possible to measure the reception quality by using a synchronization signal, a signal of broadcast information, an individual signal to a mobile station, a multicast signal, or a combination of two or more thereof transmitted from one antenna. It has a feature. The mobile station according to claim 23 is the mobile station according to claim 21.
Or 22 in the mobile station, the quality measuring means is transmitted from at least one antenna of the base station,
The reception quality is measured by using a synchronization signal, a broadcast information signal, an individual signal to a mobile station, a multicast signal, or a combination of two or more of these.

The physical quantity used as the reception quality measured at this time is not limited to a specific physical quantity, and various physical quantities can be used. Specifically, as in claim 10, as the reception quality, a value (C / (I + N)) obtained by dividing the carrier power by the sum of the reception power, the interference power and the noise power, the interference power and the noise. The value obtained by dividing the signal power by the sum of the power (S /
(I + N)), error rate, likelihood obtained during error correction decoding, C / N ratio (Carrier to Noise Ratio), S / N ratio (Signal to Noise Ratio), correlation value obtained by despreading spreading code, Alternatively, a combination of two or more of them can be used.

Similarly, the mobile communication method according to claim 16 is the mobile communication method according to any one of claims 11 to 15, wherein the reception quality includes reception power, interference power, and noise power. A value obtained by dividing the carrier power by the sum, a value obtained by dividing the signal power by the sum of the interference power and the noise power, an error rate, a likelihood obtained at the time of error correction decoding, C / N ratio, S / It is characterized in that an N ratio, a correlation value obtained by despreading a spreading code, or a combination of two or more of these is used. A mobile station according to claim 24 is the mobile station according to any one of claims 21 to 23, wherein carrier power is divided by a sum of received power, interference power, and noise power as reception quality. The value obtained,
A value obtained by dividing the signal power by the sum of the interference power and the noise power, an error rate, a likelihood obtained at the time of error correction decoding, C
It is characterized in that the / N ratio, the S / N ratio, the correlation value obtained by despreading the spreading code, or a combination of two or more of these is used.

As described above, according to the present invention, based on the reception quality of the signal measured by the mobile station, at least one antenna whose reception quality is relatively good is addressed to the mobile station. Since the signal (including the multicast signal) is transmitted, it is possible to improve the reception quality of the signal in the mobile station, prevent repeated retransmission requests from the mobile station, and improve the throughput.

Further, when the present invention is used in combination with site diversity, the effect of increasing the diversity gain can be obtained for shadowing by using a plurality of base stations.
Further, because of the feature of the present invention that a plurality of antennas are used in one base station, the control time can be shortened as much as possible, so that a large diversity gain can be realized even with respect to fading. As described above, by applying the site diversity to the present invention, the maximum diversity gain can be obtained.

In order to solve the above-mentioned problems, the present invention comprises, as described in claim 25, a mobile communication system comprising a mobile station and a base station for transmitting / receiving a signal while making an automatic retransmission request. In the signal transmission method according to, the mobile station measures the reception quality of the radio signal transmitted from the base station, notifies the base station of the reception quality of the measured radio signal, and the base station is notified of the reception quality. Based on the received quality, the signal retransmitted by the mobile station is transmitted so as to meet the required received quality of the mobile station.

According to the present invention, the base station adapts the signal retransmitted by the mobile station to the required reception quality that the mobile station satisfies, based on the reception quality of the radio signal notified from the mobile station. Therefore, it is possible to prevent the low reception quality state from continuing due to the effects of fading and shadowing as in the conventional case. As a result, it is possible to reduce the number of repetitions of the retransmission request from the mobile station, and it is possible to improve the throughput.

The radio signal from the base station measured by the mobile station is, as described in claim 26, in the signal transmitting method, the radio signal transmitted from the base station is a plurality or a single radio channel. Is configured to be.

Further, the kind of the radio channel from the base station measured by the mobile station is, for example, as described in claim 27, broadcast among a plurality of or a single radio channel transmitted from the base station. The mobile station is configured to use an information channel, a dedicated channel, a multicast channel, or a combination thereof as a radio channel for measuring reception quality.

According to the present invention, any radio channel transmitted from the base station can be used for measuring the reception quality at the mobile station.

As for the reception quality of the radio channel measured by the mobile station, as described in claim 28, in the signal transmission method, the reception quality is the reception power or (Equation 1) C / ( I + N) C: Carrier power I: Interference power N: Noise power or (Equation 2) S / (I + N) S: Signal power I: Interference power N: Noise power or (Equation 3) C / N C: Carrier power N: Noise power or (Formula 4) S / N S: Signal power N: Noise power or error rate, or likelihood obtained at error decoding, or base station transmission power value, or increase or attenuation amount of base station transmission power, Alternatively, it is configured to be either of these combinations.

Further, the radio channel used for radio transmission between the mobile station and the base station is, in the signal transmitting method, as described in claim 29, between the base station and the mobile station. The transmitted and received radio channels are configured to be at least one of subcarrier channels or orthogonal subcarrier channels or frequency channels or frequency channels in different frequency bands.

According to the present invention, a subcarrier channel is used when the transmission system for transmitting and receiving signals between a base station and a mobile station is a multicarrier transmission system, an orthogonal subcarrier channel is used when an OFDM transmission system, and an FDM transmission is performed. It is possible to use frequency channels in the system and frequency channels in different frequency bands in the multiband transmission system.

From the viewpoint of enabling the notification of the measured reception quality when the mobile station notifies the base station of the retransmission request, the present invention provides the signal transmission as described in claim 30. In the method, the mobile station is configured to notify the base station of the retransmission request together with the measured reception quality of the radio signal when the retransmission request of the received signal is required.

Further, from the viewpoint of enabling the notification of the measured reception quality when the mobile station notifies the base station of the arrival confirmation of the received packet, the present invention is described in claim 31. Thus, in the signal transmission method, the mobile station, when notifying the base station of the arrival confirmation of the received signal, notifies the base station of the measured reception quality of the plurality of or single radio channels. Is configured as follows.

As for the information relating to the reception quality notified from the mobile station to the base station, as described in claim 32, in the signal transmission method, the mobile station has a plurality of single radio channels. No. and the reception quality of the radio channel or the channel number of the reception quality within a predetermined range are notified to the base station as the reception quality of the measured plural or single radio channels.

Further, the information relating to the reception quality is as described in claim 33, in the signal transmitting method,
The mobile station is configured to notify the base station of the number of a plurality of or a single radio channel that has obtained the required reception quality including the reception quality that maximizes the reception quality at the mobile station, together with the obtained reception quality. .

From the viewpoint of changing and transmitting the radio channel used for signal transmission so as to improve the reception quality in the mobile station, the present invention provides the signal transmission method according to claim 34, in which the base station is used. The station, based on the notification from the mobile station, the mobile station obtains a radio channel satisfying the required reception quality, and using the obtained radio channel,
The mobile station is configured to transmit a signal requested to be retransmitted.

According to the present invention, the base station sets the radio channel so that the mobile station can receive the signal for which retransmission is requested from the mobile station based on the reception quality notified from the mobile station, with the required reception quality. Change it and send it.
It is not always necessary to use a predetermined radio channel for signal transmission to the mobile station. That is, since the wireless channel is adaptively changed so as to improve the reception quality in the mobile station, the mobile station can receive a signal with good reception quality, and as a result, the number of retransmission requests is reduced. As a result, throughput can be improved.

From the viewpoint that the required reception quality in the mobile station can be maintained by performing signal transmission to the corresponding mobile station using the radio channel even after the radio channel is changed as described above. The present invention provides the signal transmitting method as set forth in claim 35, wherein the base station is addressed to the mobile station even after transmitting the signal requested to be retransmitted by the mobile station through the obtained wireless channel. The signal is transmitted using the obtained wireless channel.

From the viewpoint of reducing interference with other mobile stations, the present invention provides the signal transmission method as described in claim 36, in which the base station is based on a notification from the mobile station. Satisfying the required reception quality at the mobile station,
The number of the radio channel to be transmitted and the transmission power of the radio channel are determined so that the transmission power from the base station becomes a predetermined value.

According to the present invention, when a retransmission request is sent from a mobile station, the retransmission request is sent on a radio channel in which the transmission power from the base station reaches a predetermined value while satisfying the required reception quality at the mobile station. The existing signal is transmitted. Therefore, if the predetermined value is set to the minimum value, the mobile station can receive the signal requested for retransmission with the required reception quality even if the transmission power from the base station is minimum. That is, since the transmission power from the base station is suppressed to the minimum and transmitted, it is possible to reduce interference with other mobile stations that do not receive the retransmission request signal.

Further, according to the present invention, from the viewpoint of improving the reception quality of signals received by mobile stations, even in the case of multicast transmission in which the same signal is transmitted to a plurality of mobile stations,
The present invention, as described in claim 37, in the signal transmitting method, when the base station transmits the same multicast signal to a plurality of mobile stations, based on a notification from each mobile station, Satisfies the required reception quality at each mobile station,
Further, the number of a plurality of or a single radio channel transmitting the multicast signal and the transmission power of the radio channel are determined so that the transmission power from the base station becomes a predetermined value.

Further, according to the present invention, in the signal transmitting method as set forth in claim 38, when the base station transmits the same multicast signal to a plurality of mobile stations, each base station notifies the mobile station of the same multicast signal. Among the channel numbers of the reception quality within the predetermined range, the number of the wireless channel that can be regarded as having many retransmission requests from the mobile station is obtained.

Further, according to the present invention, in a mobile communication system comprising a mobile station and a base station for transmitting and receiving a signal while making an automatic retransmission request, the mobile station The receiving quality measuring means for measuring the reception quality of the radio signal transmitted from the base station, and the reception quality notifying means for notifying the base station of the reception quality of the measured radio signal, the base station, The mobile station is further configured to include a transmitting unit that transmits a signal requested to be retransmitted by the mobile station so that the mobile station satisfies a required reception quality based on the reception quality notified from the mobile station.

A mobile communication system according to claim 1,
The mobile communication system according to claim 39 is different from the mobile communication system according to claim 39 in that the former is a mobile station side and the latter is a base station side, and the same technique is used for each. It belongs to the intellectual thought.

Further, according to the present invention, in a base station in a mobile communication system which comprises a mobile station and a base station and transmits and receives a signal while making an automatic retransmission request, The base station is configured to include a transmitting unit that transmits a signal requested to be retransmitted by the mobile station based on the reception quality notified from the mobile station so that the mobile station satisfies a required reception quality. It

Further, the present invention, as set forth in claim 63, is a mobile station in a mobile communication system, comprising a mobile station and a base station, for transmitting and receiving a signal while making an automatic retransmission request, The mobile station is configured to include reception quality measuring means for measuring reception quality of a radio signal transmitted from the base station, and reception quality notifying means for notifying the base station of the reception quality of the measured radio signal. To be done.

In order to more fully understand the present invention, detailed description and accompanying drawings will be given below, but the present invention is not limited to these descriptions. Further, the preferred scope of the present invention will become apparent from the detailed description given below.
However, this detailed description merely shows preferred examples of the embodiments of the present invention, and based on the technical contents clearly derived from the detailed description, within the scope and spirit of the present invention. It is possible to adopt various variations and modifications as appropriate.

Further, in the mobile communication system according to the present invention, as described in claim 53, the base station obtains a radio resource satisfying the required reception quality of the mobile station based on the notification from the mobile station. The wireless resource determining means includes a wireless resource determining means, and a signal transmitting means for transmitting a signal requested to be retransmitted from the mobile station using the wireless resource determined by the wireless resource determining means.

Furthermore, in the mobile communication system according to a fifty-fourth aspect, the transmitting means transmits a signal using radio resources in the order of the number of retransmission requests from the mobile station.

In the mobile communication system according to claim 55, the radio resource is at least one antenna,
Alternatively, the directivity of at least one antenna, or the radio channel or the transmission path, or a combination thereof is used. Here, the antenna may be single or plural, and when using a plurality of antennas, the directivity of each antenna may be different. Further, the transmission route is assumed to be a case where a signal is indirectly transmitted via a mobile station as a relay station (multi-hop connection).

[0073]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. [First Embodiment] FIG. 1 shows the first embodiment of the present invention.
~ It demonstrates using FIG. 2 base station antennas here
The case of using a book will be described, but the present invention can be realized by using any number of the base station antennas.

First, the configuration of the mobile communication system will be outlined. As shown in FIG. 1, the mobile communication system 100 includes
The base station 101 and the mobile station 111 are included.
The base station 101 includes a plurality of base station antennas 7 and 8, a plurality of transmission / reception duplexers 4 provided corresponding to the respective antennas, and an antenna switch 109 for switching the transmission / reception duplexer 4 to be used.
And CRC for the data input from the data input terminal 6.
An ARQ processor 102 that performs processing such as adding error-detectable parity such as, and performing retransmission according to a retransmission request from the mobile station, and notifying the transmitter 103 to use the antenna based on the antenna usage request, Antenna switch 1
09 includes a transmitter 103 that switches the output of 09 to transmit data from the ARQ processor 102, and a receiver 5 that receives data from the outside via the base station antennas 7 and 8 and inputs the data to the ARQ processor 102. Composed.

The mobile station 111 has a mobile station antenna 17 and
A transmission / reception demultiplexer 16, a reception quality measuring device 118 that measures the reception quality of the received signal for measuring reception quality and stores the reception quality in the memory 119, and a signal from the outside via the transmission / reception demultiplexer 16. Receiver 12 and a signal received by the receiver 12, which performs error detection using CRC and outputs the result from the data output terminal 14, and at the time of error detection, a retransmission request for received data and a base station antenna with high reception quality. ARQ processor 113 that outputs a notification of the number to transmitter 15 and AR
It is configured to include a transmitter 15 which transmits a retransmission request from the Q processor 113 and a notification of a base station antenna number of high reception quality.

In the present embodiment, the following description will be continued in the case where the received power is used as the reception quality. However, as specified in claim 10, the carrier power is divided by the sum of the interference power and the noise power. Value (ie C / (I +
N)), a value obtained by dividing signal power by the sum of interference power and noise power (that is, S / (I + N)), error rate, likelihood obtained at error correction decoding, C / N ratio, S / N
It is also possible to use a ratio, a correlation value obtained by despreading a spreading code, or a combination of two or more of these.

Next, the operation of the mobile communication system will be described with reference to FIG. In the base station 101, the data addressed to the mobile station 111 input from the data input terminal 6 is input to the ARQ processor 102. The ARQ processor 102 adds error-detectable parity such as CRC so that an error that occurs during transmission can be detected, and then stores the data and outputs it to the transmitter 103 (step 1).

Before transmitting the transmission signal of the input data, the transmitter 103 switches the output of the antenna switching unit 109 to the first antenna of the base station and outputs a signal for measuring reception quality. The signal for measuring the reception quality is transmitted from the first base station antenna 7 to the mobile station 111 via the duplexer 4 (step 2).

In the mobile station 111, the signal for measuring the reception quality is input to the reception quality measuring device 118 via the transmission / reception duplexer 16. The reception quality measuring device 118 measures the reception power value of the signal for measuring the reception quality and stores the reception power value in the memory 119 as the reception quality at the first antenna of the base station (step 3).

Next, the output of the antenna switching unit 109 is switched to the second antenna of the base station, and the signal for measuring the reception quality is output. The signal for measuring the reception quality is transmitted from the second base station antenna 8 to the mobile station 111 via the duplexer 4 (step 4).

In the mobile station 111, similarly to the above, it is input to the reception quality measuring device 118 via the transmission / reception duplexer 16, the reception power value is measured, and the reception power value is measured by the second antenna of the base station. The reception quality is stored in the memory 119 (step 5).

Then, as shown in FIG. 3 (a),
The output of the antenna switching unit 109 is switched to the base station first antenna 7 to output a data transmission signal. The transmission signal is transmitted from the first base station antenna 7 to the mobile station 111 via the duplexer 4 (step 6).

The above description is based on TDM (Time Division).
This is the case when the Multiple) method is applied, but the CDM (Code
It is also possible to apply the Division Multiple) method. This is, as shown in FIG. 3B, after spreading a signal for measuring reception quality with a spreading code uniquely corresponding to each antenna, the signal is transmitted from the corresponding antenna. The mobile station can use the received power, the correlation value, or the like, which is obtained by receiving the signal and despreading it with a spreading code uniquely corresponding to the antenna.

Hereinafter, description will be given returning to the case where the TDM method is applied. In the mobile station 111, the received signal is input to the receiver 12 via the transmission / reception duplexer 16. The signal received by the receiver 12 is used as received data for the ARQ processor 1
13 (step 7). And ARQ processor 1
At 13, error detection is performed using CRC. If no error is detected in the received data, the received data is output from the data output terminal 14 and the arrival confirmation of the data is notified to the ARQ processor 102 of the base station 101 via the uplink 21 (step 8). And step 9).

When the base station 101 receives the arrival confirmation or the notification of the retransmission request from the mobile station 111, the base station first
It is possible to improve the uplink reception quality by inputting the outputs from the antenna 7 and the base station second antenna 8 into the receiver 5 to perform antenna reception by the 2-branch diversity method. The ARQ processor 102 that has received the notification of arrival confirmation deletes the data stored for retransmission (step 13 and step 1).
4).

On the other hand, when an error is detected in the received data in step 8, the ARQ processor 113 searches the high reception quality stored in the memory 119, that is, the number of the base station antenna having the higher received power value. Then, the number of the base station antenna is output to the transmitter 15 together with the retransmission request for the received data. The transmitter 15 sends the retransmission request for the received data and the base station antenna number to the base station 1 via the uplink 21.
01 to the ARQ processor 102 (step 10,
Step 11, step 12). Upon receiving the notification of the retransmission request, the ARQ processor 102 first notifies the transmitter 103 of the antenna number requested by the mobile station 111, and then the transmitter 1
03 controls the antenna switch 109 so that it can transmit to the mobile station 111 using this antenna. Then, the data requested to be retransmitted is retransmitted from the antenna requested by the mobile station 111 (steps 13 and 15).

By storing the antenna number requested by the mobile station 111 in the ARQ processor 102, the mobile station 111 subsequently input from the data input terminal 6 will be described.
New data addressed to the mobile station 111 can be transmitted using the base station antenna having high reception quality without transmitting the above-described signal for measuring reception quality from the base station 101.

According to the first embodiment described above,
Based on the reception quality of the signal measured by the mobile station 111,
Since the signal addressed to the mobile station 111 is transmitted from the base station 101 using the antenna whose reception quality is relatively good, the reception quality of the signal in the mobile station 111 is improved and It is possible to prevent the retransmission request from being repeatedly made and improve the throughput of the mobile communication system 100.

In the above description, the signal for measuring the reception quality is transmitted before transmitting the data.
The mobile station 111 receives the synchronization signal, the broadcast information signal, the individual signal to the mobile station, the multicast signal, or a combination of two or more of them, and stores them in the memory 119 as described in 1. By constantly updating the contents, the present invention can be realized without transmitting a signal for measuring reception quality before transmitting data.

Further, this embodiment is applicable to a mobile station which functions as a relay station instead of the base station, assuming a case of multi-hop connection. In this case, the mobile station 111, which is the transmission source of the retransmission request, has previously recognized the presence of the surrounding mobile stations that are relay stations, and the retransmission is performed by designating the transmission path including the mobile station (relay station). Request. Similarly,
The base station 101, which is the transmission source of the signal in response to the retransmission request,
Knowing in advance the presence of surrounding mobile stations that are relay stations,
It responds to the retransmission request by designating the transmission path including the mobile station (relay station).

[Second Embodiment] The configuration of a second embodiment of the present invention will be described with reference to FIG. The present embodiment is a case of multicast transmission in which the same data (referred to as multicast data in the present embodiment) is transmitted from a base station to a plurality of mobile stations, and a retransmission request is notified when an error is detected. This will be described as an automatic resend request only performed. Moreover, although there are a plurality of mobile stations that receive the multicast data, the operation of one of the mobile stations will be described below. Of course, the other mobile stations which are the omitted multicast targets also perform the same operation.

In the base station 201, the multicast data destined for the mobile station 211 inputted from the data input terminal 6 is
Input to the RQ processor 202. The ARQ processor 202 stores the multicast data in the memory 21 for retransmission.
After being stored in 0, CRC is added, error correction coding is performed, number information of the base station antenna used for transmission is further added, and then output to the transmitter 3. Then, the antenna switch 109 is controlled so that the antenna indicated by the assigned base station antenna number information is used for transmission. The transmitter 3 modulates the input multicast data into a transmission signal (multicast signal) and then outputs it to the antenna switching unit 109. The antenna switch 109 is capable of transmitting a multicast signal from the base station antenna (one of the base station first antenna 7 or the base station second antenna 8) corresponding to the number information via the transmission / reception duplexer 4. Has become.

In this embodiment, it is assumed that the antenna switching unit 109 is controlled so that the multicast signal can be transmitted by preferentially using the base station antenna with a large number of requests from the mobile station that is the target of the multicast. That is,
Before outputting the multicast data to the transmitter 3, the ARQ processor 202 searches the storage information of the memory 210 for the number information of the base station antenna that has a large number of requests from the mobile station, and the base station corresponding to the number. The antenna switch 109 is controlled so as to transmit the multicast signal from the antenna. The memory 210 is used to store the correspondence between the number of requests from mobile stations and the base station antenna number.

In the mobile station 211, the downlink 22
The multicast signal received by the mobile station antenna 17 via the is input to the receiver 12 via the transmission / reception duplexer 16. The receiver 12 demodulates the received multicast signal and outputs it to the ARQ processor 213 as received multicast data. The ARQ processor 213, after decoding the error correction code, performs error detection using the added CRC. At the same time, the likelihood obtained at the time of decoding the error correction code is stored in the memory 119 together with the base station antenna number information added to the received multicast data. The above likelihood is calculated as BCH as error correction coding.
The number of correction bits can be used in the case of a code or a block code such as an RS code, and the metric can be used in the case of a convolutional code.

When there is no error in the received multicast data due to the error detection in the CRC, the ARQ processor 21
3 does not send any signal to the base station 201, and outputs the received multicast data from the data output terminal 14. On the other hand, when an error is detected in the received multicast data, the ARQ processor 213 searches the number information of the high reception quality base station antenna stored in the memory 119 and retransmits the received multicast data. The number information of the base station antenna is output to the transmitter 15 together with the request. The transmitter 15 sends the retransmission request of the received multicast data and the number information of the base station antenna to the uplink 2
1 to the base station 201.

In the base station 201, the retransmission request of the received multicast data and the number information of the base station antenna are received by the receiver 5, and the receiver 5 transmits the ARQ processor 20.
2 is output. As described above, the ARQ processor 202 measures the required number of base station antenna numbers requested from each mobile station, and stores the correspondence between the base station antenna numbers and the number of mobile stations requesting them in the memory 210. And remember
After that, when retransmitting the multicast data, the base station antenna with a large number of requests is preferentially used for the retransmission.

Next, the cooperative operation of the base station 201 and a plurality of mobile stations (here, four mobile stations A to D, as an example) will be described with reference to FIG. In addition, mobile station A ~
The configuration of the mobile station D is the same as that of the mobile station 211 of FIG. 4, and the memory 210 provided in the base station 201 and the memory 119 provided in each mobile station are in an initial state in which no data is stored yet.

The base station 201 adds the number information of the first antenna 7 to the multicast data and transmits the added multicast data to all mobile stations (mobile station A to mobile station D) to be multicast. For example, since the mobile station A to the mobile station C have detected an error in the received multicast data, a request to retransmit the data and an antenna use request to use the second antenna 8 whose error rate is not stored in the memory 119 are made. To the base station 201. Mobile station D
Since no error is detected in the received multicast data, no signal is transmitted to the base station 201.

Next, in the base station 201, the ARQ processor 2
02 measures the number of requests for antenna number information used at the time of retransmission from mobile station A to mobile station C, and the measurement result, that is, the number of retransmission requests at the second antenna 8 is 3, and at the first antenna 7 Information indicating that the number of retransmission requests is 0 is stored in the memory 210.
Remember. Therefore, the base station 201 has the memory 210
Based on the above-mentioned measurement result stored in, the second antenna 8 having the largest number of retransmission requests transmits the multicast data to be retransmitted (hereinafter referred to as retransmission multicast data) to the mobile stations A to C ( In FIG. 5, it corresponds to “first retransmission”).

In the first reception of the retransmitted multicast data, mobile stations A to C detect the error again, and therefore notify base station 201 of the retransmission request. At this time, the mobile station A has a lower error rate when receiving the multicast data transmitted by the second antenna 8. Therefore, the base station 201 transmits the retransmission request together with the notification of the retransmission request.
To request. On the other hand, in mobile station B and mobile station C, the first
Since the error rate when the multicast data transmitted by the antenna 7 is received is lower, the base station 201 is requested to retransmit with the first antenna 7 together with the notification of the retransmission request.

In the base station 201, the memory 210 stores information indicating that the number of retransmission requests for the second antenna 8 is one and the number of retransmission requests for the first antenna 7 is two. For this reason,
Based on the measurement result stored in the memory 210, the base station 201 transmits retransmission multicast data from the first antenna 7 having the maximum number of retransmission requests to the mobile stations A to C (“2” in FIG. 5). Corresponding to "the second retransmission").

In the second reception of the retransmitted multicast data, mobile station B and mobile station C did not detect any error, and therefore nothing is transmitted to base station 201. On the other hand, although an error is detected in the mobile station A, the base station antenna used for transmission is not the antenna requested by the mobile station A and therefore does not notify the base station 201 of the retransmission request. This is because it is expected that retransmission multicast data will be transmitted using the second antenna 8 requested by the mobile station A in the next transmission.

Then, the base station 201 transmits the retransmission multicast data to the mobile station A from the second antenna 8 having the second largest number of retransmission requests, based on the measurement result stored in the memory 210 (in FIG. It corresponds to the "third retransmission").

Since mobile station A did not detect any error in receiving the third retransmission multicast data, mobile station A does not transmit anything to base station 201, and base station 201
End the multicast transmission from. With the above operation, it is possible to realize the transmission of the high quality signal by the automatic retransmission request of the present invention during the multicast data transmission.

According to the second embodiment described above, retransmission multicast data is transmitted from the base station 201 in order from the base station antenna with the largest number of antenna use requests required based on the reception quality of the signal measured by each mobile station. Therefore, for the mobile communication system as a whole, it is possible to improve the reception quality of retransmitted multicast data in more mobile stations, reduce the total number of retransmission requests, and improve the throughput of the entire system. You can

In the above first and second embodiments, an example in which the mobile station transmits an antenna use request indicating that one of the plurality of base station antennas is to be used has been described.
When a large number of base station antennas are provided, the mobile station is configured to transmit an antenna use request specifying two or more base station antennas with good reception quality as the use request antennas. Good.

By the way, the present invention can be said to be a diversity method in which one base station uses a plurality of antennas, and site diversity is known as a diversity method in which a plurality of base stations uses one antenna.

In this site diversity, there is no correlation with respect to shadowing (short-term median fluctuation), so that the diversity gain is large, but there is no correlation with respect to fading (instantaneous fluctuation), so there is diversity. Although the gain is large, it is difficult to realize diversity gain because the control signal is transmitted between multiple base stations and the delay becomes large with respect to the control time. Since it is pre-occupied for control, it has the drawback of being inefficient.

When the present invention is used in combination with the site diversity described above, the effect of increasing the diversity gain can be obtained for shadowing by using a plurality of base stations. Further, because of the feature of the present invention that a plurality of antennas are used in one base station, the control time can be shortened as much as possible, so that a large diversity gain can be realized even with respect to fading. As described above, by applying the site diversity to the present invention, the maximum diversity gain can be obtained.

The present embodiment is applicable to a mobile station that functions as a relay station instead of the base station, assuming a multi-hop connection. In this case, the mobile station 211, which is the transmission source of the retransmission request, has previously recognized the presence of the surrounding mobile stations that are relay stations, and the retransmission is performed by designating the transmission path including the mobile station (relay station). Request. Similarly,
The base station 201, which is the transmission source of the signal in response to the retransmission request,
Knowing in advance the presence of surrounding mobile stations that are relay stations,
It responds to the retransmission request by designating the transmission path including the mobile station (relay station).

[Third Embodiment] A third embodiment of the present invention will be described with reference to FIGS. 6 and 7. In this embodiment, a case where the base station transmits a signal to the mobile station by the multiband transmission method will be described as an example.

FIG. 6 is a block diagram of a mobile communication system according to this embodiment, which is a base station 301 and a mobile station 311.
Composed of. The base station 301 has an ARQ processor 302.
, A transceiver 303, a signal input terminal 304, a base station antenna 305, and a channel determiner 306. The mobile station 311 has a transceiver 312 and an ARQ.
A processor 313, a signal output terminal 314, a mobile station antenna 315, a reception quality measuring instrument 316, and a memory 317 are provided.

Next, the operation will be described with reference to the flowchart of FIG. In the base station 301, the signal input terminal 3
The signal addressed to the mobile station 311 input from 04 is input to the ARQ processor 302. The ARQ processor 302 adds an error-detectable parity such as CRC so as to detect an error that occurs during transmission, and then stores the signal for retransmission (T2) and outputs the signal to the transceiver 303. The device 303 notifies the mobile station 311 of the transmission start of the signal addressed to the mobile station 311 and the frequency channel number of the frequency band for transmitting the signal (T3), and then transmits the signal to the mobile station 311 (T4). ).

If the offset of the frequency channel number of the frequency band used for signal transmission is known in advance,
The notification of the frequency channel number of the frequency band can be omitted.

On the other hand, in the mobile station 311, the reception quality measuring device 316 receives the C / I (Carrier-to-Interfere ratio) of the dedicated channel or the like transmitted from the base station 301 as the reception quality. As the frequency channel number in each measured frequency band and the C / C of the frequency channel.
The relationship with I is stored in memory 317.

[0116] As described above, the reception quality measuring instrument 316 uses the C / s such as dedicated channels transmitted from the base station 301.
I is continuously measured at all times. Therefore, the memory 3
The relationship between each frequency channel number in each frequency band stored in 17 and the C / I of the frequency channel is constantly updated.

In such a mobile station 311, the signal transmitted from the base station 301 to the mobile station is sent to the downlink 3
The signal is input to the ARQ processor 313 after being received (T5) by the transceiver 312 via 22. ARQ processor 31
3 performs error detection of the received signal using CRC.
When no error is detected in the received signal (NO in T6), the received signal is output from the signal output terminal 314, and the arrival confirmation of the received signal is confirmed by the ARQ processor of the base station 301 via the uplink 321. Notify 302 (T
7). Then, the ARQ processor 302, which has received the notification of arrival confirmation from each mobile station, deletes the signal addressed to the mobile station stored for retransmission (T9 and T10). At this time, the notification of the arrival confirmation (T7) is omitted, the process for detecting the retransmission request (T9) is provided with a timeout determination function, and if the retransmission request is not detected within a certain period of time, the operation of T10 is performed. It may be configured to be executed.

On the other hand, when an error is detected in the signal received at T6 (YES at T6), the ARQ processor 313 is
The retransmission request of the received signal is notified to the ARQ processor 302 of the base station 301 via the uplink 321 and the maximum C among the frequency channel numbers of the measured frequency bands stored in the memory 317 is transmitted. Frequency channel number of the frequency band that is / I and C / of the frequency channel
The I is notified to the channel determiner 306 of the base station 301 (T8).

When a retransmission request is input to the ARQ processor 302, it is determined at T9 whether or not the input signal is a retransmission request. In the determination of T9, if the retransmission request is detected (YES in T9), the detection result is notified to the channel determiner 306. The channel determiner 306 uses the AR
When the notification that the retransmission request is detected is received from the Q processor 302, the mobile station 311 based on the notified C / I.
The transmission power is calculated so that the reception quality in (1) becomes a required value (T11), and the transceiver 303 is controlled to retransmit the signal requested to be retransmitted with the notified frequency channel number and the obtained transmission power. When the signal retransmitted from the ARQ processor 302 is input to the transceiver 303, the transceiver 303 broadcasts the frequency channel number of the frequency band used for retransmission (T12), and then transmits the retransmission signal (T13). ).

The base station 301 also receives a new signal addressed to the mobile station from the signal input terminal 304 thereafter.
Transmission is performed with the frequency channel number and transmission power of the frequency band acquired above.

When the candidate of the frequency band station wave number channel number used for retransmission is known in advance, the notification of the frequency channel number of the frequency band used for retransmission is omitted, and the mobile station sets the frequency channel number of the frequency band. The retransmitted signal is received with the frequency channel number of the frequency band having the highest reception quality from among the candidates.

As described above, in the present embodiment,
The case where the multi-band transmission method is used as an example of the transmission method between the base station 301 and the mobile station 311 has been described. In addition, the transmission method between the base station 301 and the mobile station 311 can be used as an FDM (Frequency Division Multiplexing). Multiplex) transmission method, multi-carrier transmission method, OF
DM (Orthogonal Frequency Division Multiplexing:
It is also possible to use an orthogonal frequency division multiplexing) transmission system. For example, when the FDM transmission method is used, the frequency channel number and the reception quality of the frequency channel, when the multicarrier transmission method is used, the subcarrier channel number and the reception quality of the subcarrier channel, and when the OFDM transmission method is used. By notifying the base station 301 of the orthogonal subcarrier channel number and the reception quality of the orthogonal subcarrier channel, the reception quality at the mobile station 311 can be improved by the same operation as in the first embodiment.

As described above, according to the third embodiment of the present invention, the base station 301 has the frequency channel number notified from the mobile station 311 and the C / C of the frequency channel.
Based on I, the mobile station calculates the transmission power that achieves the required reception quality, and retransmits the signal requested by the mobile station 311 for retransmission with the notified frequency channel number and the calculated transmission power. It is possible to prevent the 311 from remaining in low reception quality due to the effects of fading and shadowing. As a result, the repetition of the retransmission request from the mobile station 311 can be reduced and the throughput can be improved. Further, since the retransmission signal is retransmitted by switching to the frequency channel that minimizes the transmission power from the base station 301, it is possible to reduce interference with the mobile station 311 that does not receive the retransmission signal.

The present embodiment is applicable to a mobile station that functions as a relay station instead of the base station, assuming a case of multi-hop connection. In this case, the mobile station 311 that is the transmission source of the retransmission request recognizes in advance the presence of surrounding mobile stations that are relay stations, and retransmits by specifying the transmission path that includes the mobile station (relay station). Request. Similarly,
The base station 301, which is the transmission source of the signal in response to the retransmission request,
Knowing in advance the presence of surrounding mobile stations that are relay stations,
It responds to the retransmission request by designating the transmission path including the mobile station (relay station).

[Fourth Embodiment] Next, a fourth embodiment of the present invention will be described with reference to FIGS. In the present embodiment, a case where the base station transmits a multicast signal to each mobile station by the FDM transmission method will be described as an example.

FIG. 8 is a block diagram of a mobile communication system in the fourth embodiment, which is composed of a base station 401 and a mobile station 411, as in the third embodiment. The base station 401 includes an ARQ processor 402, a transceiver 403, a signal input terminal 404, and a base station antenna 405.
And a channel determiner 406. The mobile station 411 includes a transceiver 412 and an ARQ processor 413.
, A signal output terminal 414, a mobile station antenna 415, a reception quality measuring instrument 416, and a memory 417.

Next, the operation of the mobile communication system in the present embodiment will be described with reference to the flowchart in FIG. Here, although there are a plurality of mobile stations in a group that receives one multicast signal, only one mobile station in the group will be taken up and described below. In addition,
The other mobile stations belonging to the group also perform the same operation as the mobile station described below.

At the base station 401, the multicast signal addressed to the mobile station 411 inputted from the signal input terminal 404 is AR.
Input to the Q processor 402. The ARQ processor 402 is
After adding error-detectable parity such as CRC so that an error that occurs during transmission can be detected, the multicast signal is stored for retransmission (T22) and is output to the transceiver 403. The transceiver 403 notifies each mobile station of the start of transmission of the multicast signal and the frequency channel number for transmitting the multicast signal, and then transmits the multicast signal to the mobile station 411 (T23 and T24). It should be noted that, if the candidate for the frequency channel number used for transmitting the multicast signal is known in advance, the notification of the frequency channel number can be omitted.

On the other hand, in the mobile station 411, the reception quality measuring instrument 116 continuously measures the C / I of the individual channel or the like transmitted from the base station 401 as the reception quality (T21), and the measurement is performed. Memory 1 for the relationship between the selected frequency channel number and C / I of the frequency channel
Set to 17.

[0130] As described above, the reception quality measuring instrument 416 uses the C / s such as dedicated channels transmitted from the base station 401.
I is continuously measured at all times. Therefore, memory 1
The relationship between the frequency channel number stored in 17 and the C / I of the frequency channel is constantly updated.

In the present embodiment, the case where C / I is used as the reception quality will be described below.
Or C / (I + N), or S / (I + N), or C /
N, or S / N, an error rate, a likelihood obtained at the time of error decoding, a base station transmission power value, an increase amount or an attenuation amount of the base station transmission power, or a combination thereof may be used as the reception quality. Good. "C" of C / (I + N) represents carrier power, and "S" of S / (I + N) represents signal power. Further, the above C / (I + N) and the above S / (I +
"I" in N) represents interference power, and "N" represents noise power. Thus, according to the present invention, any signal transmitted from the base station 401 transmitting a multicast signal can be used for measuring the reception quality.

In the mobile station 411, the base station 401
The multicast signal transmitted from the downlink 422
After receiving (T25) at the transceiver 412 via
Input to the RQ processor 413. The ARQ processor 413 is
Error detection is performed on the received multicast signal using CRC. Then, when no error is detected in the received multicast signal (NO in T26), the received multicast signal is output from the signal output terminal 414, and the arrival confirmation of the received multicast signal is transmitted from the base station 401 via the uplink 421. Notify the ARQ processor 402 (T
27).

The ARQ processor 402, which has received only the notification of the arrival confirmation from each mobile station, deletes the multicast signal stored for retransmission (N in T29).
O and T30). At this time, the notification of the above-mentioned arrival confirmation (T2
By omitting step 7), the item for detecting the retransmission request (T29) may be provided with a timeout determination function, and if the retransmission request is not detected within a certain period of time, the operation of (T30) may be executed. .

On the other hand, when an error is detected in the received multicast signal (YES in T26), the ARQ processor 413
Notifies the ARQ processor 402 of the base station 401 of the retransmission request of the received multicast signal via the uplink 421. Also, the ARQ processor 413 accesses the memory 417, and measures the latest measured frequency channel number stored in the memory 417 and the C / I of the frequency channel.
To the channel determiner 406 of the base station 401 (T
28).

When a retransmission request is input to ARQ processor 402, it is determined whether or not the signal input in (T29) is a retransmission request. In the determination of T29, if the retransmission request is detected (YES in T29), the detection result is notified to the channel determiner 406. Channel determiner 406
Upon receiving the notification that the retransmission request is detected by the ARQ processor 402, the frequency channel number and the frequency at the time of retransmission based on the frequency channel number notified from each mobile station and the C / I of the frequency channel. After calculating the transmission power of the channel (T31), the transceiver 403 is controlled so as to retransmit with the determined frequency channel number and transmission power.

Then, the multicast signal stored for retransmission in the ARQ processor 402 is transmitted / received by the transceiver 4
03, the transceiver 403 broadcasts a plurality of or a single frequency channel number used for transmission (T32), and then transmits the input retransmission multicast signal (T33).

Each mobile station that receives the retransmitted multicast signal receives the retransmitted multicast signal on the channel having the frequency channel number that gives the maximum reception quality in the mobile station from the broadcast frequency numbers. If a plurality of or single frequency channel number candidates used for retransmission are known in advance, the notification of the frequency channel number for retransmitting the multicast signal is omitted, and each mobile station selects from among the frequency channel number candidates. The retransmitted multicast signal is received with the frequency channel number that provides the maximum reception quality.

The base station 401 can also transmit a new multicast signal input from the signal input terminal 404 in the subsequent processing with a plurality or a single frequency channel number and transmission power determined above. is there.

As described above, in the fourth embodiment, the case where the FDM transmission method is used has been described as an example of the transmission method between the base station 401 and the mobile station 411. , Base station 401 and mobile station 411
Multi-carrier transmission method, OFDM
It is also possible to use a transmission method or a multi-band transmission method. For example, when using a multicarrier transmission method, a subcarrier channel number and reception quality of the subcarrier channel, and when using an OFDM transmission method, orthogonal subcarrier channel number and reception quality of the orthogonal subcarrier channel, multiband transmission method In the case of using, by notifying the base station 401 of the frequency channel number of the frequency band and the reception quality of the frequency channel of the frequency band, the reception quality at the mobile station 411 can be improved by the same operation as this embodiment.

As described above, according to the fourth embodiment of the present invention, the base station 401 transmits the multicast signal based on the frequency channel number notified from each mobile station and the C / I of the frequency channel. After calculating the frequency channel number at the time of retransmission and the transmission power of the frequency channel, retransmission is performed with the determined frequency channel number and transmission power.
Therefore, the mobile station 411 can receive the retransmitted multicast signal with the required reception quality even when it is affected by fading or shadowing. As a result, the number of repetitions of retransmission requests from the mobile station 411 is reduced, and the throughput can be improved. Further, it is possible to reduce interference with mobile stations that do not receive the retransmission multicast signal.

Next, an example of the procedure for determining the frequency channel number and the transmission power of the radio channel will be described with reference to FIG. 10, assuming the mobile communication system in the present embodiment.

The determination of the frequency channel number and the transmission power is calculated by the channel determiner 406 of the base station.
FIG. 10 is a flowchart (algorithm) showing a processing procedure for determining the frequency channel number and the transmission power. FIG. 11 shows an example of reception quality of each frequency channel in each mobile station 1 to 3.

For convenience of explanation, the number of frequency channels is 3 below.
One case (f = 0 to 2) can be used will be taken as an example. Therefore, up to three frequency channels can be selected, and there are seven (c = 0 to 6) frequency combinations. Further, the reception quality of each frequency channel in each mobile station will be described on the assumption that it has been notified to the channel determiner 406. For example, as shown in FIG. 11, the reception quality at each mobile station 1 to 3 is determined by the channel determiner 40.
6 has been notified.

FIG. 11 is a graph showing an example in which the mobile stations 1 to 3 monitor the reception quality of the signals of the first to third frequency channels transmitted from the base station 401 as described above. Is. In FIG. 11, the horizontal axis represents frequency (f)
However, the reception quality (dB) is specified on the vertical axis. As shown in FIG. 11, for example, in the mobile station 1, the reception quality of the first frequency channel (f = 0) is 0 dB, the reception quality of the second frequency channel (f = 1) is −1 dB, and the third frequency channel ( This shows that the reception quality of f = 2) is -15 dB.

Similarly, in the mobile station 2, the reception quality of the first frequency channel (f = 0) is -20 dB, the reception quality of the second frequency channel (f = 1) is 0 dB, and the third frequency channel (f = 2). ) Represents that the reception quality is -10 dB. In the mobile station 3, the first frequency channel (f =
0) reception quality is −15 dB, second frequency channel (f =
The reception quality of 1) is -20 dB and the third frequency channel (f =
It shows that the reception quality of 2) is 0 dB. In addition,
In this example, the required reception quality (Qre
q) is assumed to be 0 dB.

Here, as a premise for explaining the flowchart of FIG. 10, a correspondence relationship between a combination of frequency channels f assumed to be used for retransmission and c representing a classification of the combination is shown below. c = 0: f = 0 (using the first frequency channel) c = 1: f = 1 (using the second frequency channel) c = 2: f = 2 (using the third frequency channel) c = 3: f = 0,1 (uses first and second frequency channels) c = 4: f = 1,2 (uses second and third frequency channels) c = 5: f = 0,2 (first and third) Frequency channel is used) c = 6: f = 0, 1, 2 (uses first, second and third frequency channels) In FIG. 10, first, c = 0, that is, only the first frequency channel is used. Assuming that the mobile station is mobile station 1
(I = 0) is set (T41), and the calculation of (T42) is executed. At T2, MAX {q (i, f)} is calculated. Here, q (i, f) represents the reception quality of the frequency channel f at the mobile station i. In addition, MAX {q (i,
f)} is the maximum q among all frequency channels f that can be taken by the combination classification c of frequency channels in the mobile station i.
(I, f) is shown. In this example, when i = 0, c = 0
Since the maximum reception quality at the time of is f = 0, it is calculated as Q (0,0) = q (0,0) = 0 dB (see FIG. 11).

When q (0,0) is obtained in this way,
In the next (T43), i is incremented by "1" (i = 1, mobile station 2). At (T43), a modulo operation is performed, so that the remainder obtained by dividing (i + I) by M (the total number of mobile stations reporting the request) is incremented until it becomes zero. Therefore, 1mod3 (=
M) and i ≠ 0, the determination at T44 is NO, and the process from T42 is executed again. That is, until i equals M (until i = 3), T42-
The process of T43 is repeatedly executed.

Therefore, since NO is obtained by the determination at T44, the process returns to T42, MAX {q (i, f)} for the mobile station 2 (i = 1) is calculated, and the result shown below is obtained. It shall be obtained (see FIG. 11). Q (1,0) = MAX {q (1,0)} =-20 dB Further, i (2) (mobile station 3) is calculated in the same manner as above, and Q (2,0) = MAX {q ( 2, 0)} = − 15 dB is obtained (see FIG. 11).

In this way, all mobile stations (i = 0 to 2)
When T42 is executed (c = 0) with respect to, i = 0 in the determination of T44 (YES in T44), and the process proceeds to the next T45. At T45, P (c) = Σ {Qreq−MIN
(Q (i, f))} is calculated as follows. Here, Qreq represents the required reception quality, and P (c) represents the transmission power from the base station when the frequency channel combination classification is c. When c = 0, it is calculated as follows. P (0) = Qreq-MIN {Q (0,0), Q (1,0), Q (2,0)} = 0 dB-MIN {0 dB, -20 dB, -15 dB} = 0 dB-(-20 dB) = + 20 dB Therefore, when c = 0, P (0) = + 20 dB is calculated.

In this way, P in the case of c = 0
When the calculation of (c) is completed, the process proceeds to the next T46, and the frequency channel combination classification c is incremented. In this case, 1mod6 (Nc) and c ≠ 0 (T4
The determination result in 7) is NO, and the processing from (T42) is executed again. That is, the processes of T42 to T46 are repeatedly performed until c and Nc become equal (until c = 6 in this example).

The results of calculating Q (i, f) and P (c) for c = 1 to c = 6 in the same manner as described above will be shown below. c = 1) Q (0,1) = MAX {q (0,1)} =-1 dB (see FIG. 11) Q (1,1) = MAX {q (1,1)} = 0 dB ( (Refer to FIG. 11) Q (2,1) = MAX {q (2,1)} = − 20 dB (Refer to FIG. 11) P (1) = Qreq−MIN {Q (0,1), Q (1, 1), Q (2,1)} = 0 dB-MIN {-1 dB, 0 dB, -20 dB} = 0 dB-(-20 dB) = + 20 dB c = 2) Q (0,2) = MAX {q (0 , 2)} = − 15 dB (see FIG. 11) Q (1,2) = MAX {q (1,2)} = − 10 dB (see FIG. 11) Q (2,2) = MAX {q (2 , 2)} = 0 dB (see FIG. 11) P (2) = Qreq−MIN {Q (0,2), Q (1,2), Q (2,2)} = 0 dB−MIN {−15 dB, −10 dB, 0 dB} = 0 dB − (− 15 dB) = + 15 dB c = 3) Q (0,0) = MAX {q (0,0) q (0,1)} = q (0,0) = 0 dB Q (1,0) = MAX {q (1,0), q (1,1)} = q (1,1) = 0 dB Q ( 2,0) = MAX {q (2,0), q (2,1)} = q (2,0) = − 15 dB P (3) = Qreq−MIN {Q (0,0), Q (2 , 0)} + Qreq−MIN {Q (1,1)} = 0 dB−MIN {0 dB, −15 dB} +0 dB−MIN (0 dB) = (+ 15 dB) + (0 dB) ≈ + 15.1 dB The above (+15 dB) The sum with (0 dB) is (+1
5 dB) and (0 dB) true values are summed to obtain the logarithm.

Since the true value of (0 dB) is “1” and the true value of (+15 dB) is “≈31.6”, x = 1 + 31.6 = 32.6 ∴10log x = 10log32.6≈ + 15.1 dB Becomes When c = 4) Q (0,1) = MAX {q (0,1), q (0,2)} = q (0,1) =-1 dB Q (1,1) = MAX {q ( 1,1), q (1,2)} = q (1,1) = 0 dB Q (2,2) = MAX {q (2,1), q (2,2)} = q (2,2) ) = 0 dB P (4) = Qreq-MIN {Q (0,1), Q (1,1)} + Qreq-MIN {Q (2,2)} = 0 dB-MIN {-1 dB, 0 dB} +0 dB-MIN (0 dB) = (+1 dB) + (0 dB) ≈ +3.5 dB The sum of (+1 dB) and (0 dB) is the same as above.
This is performed by taking the sum of the true values of (+1 dB) and (0 dB) and taking the logarithm.

Since the true value of (0 dB) is “1” and the true value of (+1 dB) is “≈1.26”, x = 1 + 1.26 = 2.26 ∴10log x = 10log2.26≈ + 3.5 dB Becomes c = 5) Q (0,0) = MAX {q (0,0), q (0,2)} = q (0,0) = 0 dB Q (1,2) = MAX {q (1 , 0), q (1,2)} = q (1,2) =-10 dB Q (2,2) = MAX {q (2,0), q (2,2)} = q (2,2) ) = 0 dB P (5) = Qreq-MIN {Q (0,0)} + Qreq-MIN {Q (1,2), Q (2,2)} = 0 dB-MIN (0 dB) +0 dB-MIN {-10 dB , 0 dB} = (0 dB) + (+10 dB) ≈ +10.4 dB Note that the sum of (0 dB) and (+10 dB) is the same as above.
It is performed by taking the sum of the true values of (0 dB) and (+10 dB) and taking the logarithm.

Since the true value of (0 dB) is "1" and the true value of (+10 dB) is "10", x = 1 + 10 = 11∴10logx = 10log11≈10.4 dB. When c = 6) Q (0,0) = MAX {q (0,0), q (0,1), q (0,2)} = q (0,0) = 0 dB Q (1,1 ) = MAX {q (1,0), q (1,1), q (1,1)} = q (1,1) = 0 dB Q (2,2) = MAX {q (2,0), q (2,1), q (2,2)} = q (2,2) = 0 dB P (6) = Qreq-MIN {Q (0,0)} + Qreq-MIN {Q (1,1)} + Qreq-MIN {Q (2,2)} = 0dB-MIN (0dB) + 0dB-MIN (0dB) + 0dB-MIN (0dB) = (0dB) + (0dB) + (0dB) ≒ + 4.8dB Same as above The sum of (+0 dB), (0 dB) and (0 dB) is performed by taking the logarithm of the sum of the true values of (0 dB), (0 dB) and (0 dB).

Since the true value of (0 dB) is "1", x = 1 + 1 + 1 = 3∴10log x = 10log3≉ + 4.8 dB. As described above, when P (0) to P (6) are calculated, the process proceeds to T48 and MIN {P (c)} is calculated. Below, MIN {P
The calculation method of (c)} is shown. MIN {P (c)} = MIN {P (0), P (1), P
(2), P (3), P (4), P (5), P (6)} =
MIN {+ 20dB, + 20dB, + 15dB, + 15.1dB,
+35 dB, +10.4 dB, +4.8 dB,} Therefore, by calculation of T48, MIN {P (c)} =
P (4) = + 3.5 dB is obtained.

As a result, the state of the combination of the frequency channels of c = 4 is finally selected, the transmission power of the second frequency channel is +1 dB, the transmission power of the third frequency channel is 0 dB, and the respective frequencies (second and second) are selected. The same multicast signal is retransmitted at the third frequency).

According to the above-described processing, it is possible to obtain the frequency channel number and the transmission power that minimize the transmission power from the base station while satisfying the required reception quality at the mobile station.

Note that this embodiment is applicable to a mobile station that functions as a relay station instead of the base station, assuming multi-hop connection. In this case, the mobile station 411, which is the transmission source of the retransmission request, has previously recognized the presence of the surrounding mobile stations that are relay stations, and the retransmission is performed by designating the transmission path including the mobile station (relay station). Request. Similarly,
The base station 401, which is the transmission source of the signal in response to the retransmission request,
Knowing in advance the presence of surrounding mobile stations that are relay stations,
It responds to the retransmission request by designating the transmission path including the mobile station (relay station).

[Fifth Embodiment] Finally, the fifth embodiment of the present invention
The embodiment will be described with reference to the configuration diagram of FIG.
In the present embodiment, a NACK-based automatic retransmission request is performed in which notification of a confirmation of arrival is not sent but only a request for retransmission is sent, and the base station inputs a multicast signal in units of packets and transmits it by a multicarrier transmission method. And In addition, by using a spreading code as the retransmission request, the base station requests retransmission even if a collision of the retransmission request signal occurs, and combines the method of detecting the packet number of the retransmission requested packet. The explanation will be given by taking the case as an example.

A method capable of detecting that retransmission is requested even if a collision of retransmission requests occurs is described in the international application (PCT / JP01 / 0
2923). FIG. 12 is a configuration diagram of a mobile communication system in the tree embodiment, and the base station 5 is the same as in the first embodiment and the second embodiment described above.
01 and a mobile station 511. Base station 50
1 comprises an ARQ processor 502, a transceiver 503, a signal input terminal 504, a base station antenna 505, a channel determiner 506, and a retransmission request signal quality measurer 507. The mobile station 511 includes a transceiver 512,
ARQ processor 513, signal output terminal 514, mobile station antenna 515, reception quality measuring instrument 516, and memory 51
And 7 are provided.

The base station 501 outputs the packet of the multicast signal input from the signal input terminal 504 to the ARQ processor 502. The ARQ processor 502 is
Transmitter / receiver 5 after adding CRC to the input packet
Output to 03. The transceiver 503 informs each mobile station of the start of packet transmission and the subcarrier number used for transmission of the packet, and then transmits the packet to the downlink 5
22 to the mobile station 511.

On the other hand, the mobile station 511 has the reception quality measuring device 5
16 continuously and continuously measures S / (N + I) of each subcarrier transmitted from the base station 501 as reception quality, and measures the measured subcarrier number and S / (N + I) of the subcarrier. The correlation with is stored in the memory 517.

In such a mobile station 511, the packet transmitted from the base station 501 is transferred to the downlink 522.
After being received by the transmitter / receiver 512 via, the signal is output to the ARQ processor 513. The ARQ processor 513 uses a CRC
Is used to detect an error in the received packet. Then, when no error is detected in the received packet, the ARQ processor 513 outputs the packet from the signal output terminal 514. Since NACK-based automatic resend request is being made,
The arrival confirmation when no error is detected is not notified to the base station 501.

When an error is detected in the received packet, the ARQ processor 513 makes a request for retransmission of the packet,
The subcarrier number of the maximum reception quality stored in the memory 517 is notified to the base station 501 via the uplink 521. In the present embodiment, a description will be given of a method in which a channel number of reception quality within a certain range is set as a subcarrier number of maximum reception quality in each mobile station and only the subcarrier is notified thereafter. A spreading code is used for the packet number for requesting retransmission and the subcarrier number used for transmitting the retransmission packet. For example, when 256 kinds of spreading codes can be used, 128 kinds of spreading codes are used to identify a packet number and the remaining 128 kinds of spreading codes are used to identify a subcarrier number.
Different spreading codes can be assigned. That is, in this case, the spreading code number transmitted from the mobile station 511 to the base station 501 is obtained by the following calculation.

Spread code number = (packet number) + (subcarrier number) × 16 For example, if the retransmission packet number is “8” and the subcarrier number requesting transmission of the retransmission packet is “3”, 8
Since + 3 × 16 = 56, the mobile station transmits the 56th spreading code as the retransmission request signal, so that even if the retransmission request signal collides with the base station 501, the correlation value or despreading by the spreading code is generated. It is possible to judge the retransmission request by using the level of the signal obtained by the above operation as the reception quality. Therefore, the base station 501 can detect that the eighth packet is requested to be retransmitted using the third subcarrier.

Regarding the spreading code transmitted by the mobile station 511, the retransmission request signal quality measuring instrument 307 of the base station 501 detects the above retransmission packet number and subcarrier number. Retransmission request signal quality measurer 307 notifies ARQ processor 502 of the detected retransmission packet signal and channel determiner 506 of the subcarrier number required to be used at the time of retransmission. Then, the ARQ processor 502 controls the transceiver 503 so as to retransmit with the searched subcarrier number after searching the packet number with the largest number of retransmission requests. The transceiver 503 notifies the AR that the subcarrier number will be used for retransmission.
The retransmission packet input from the Q processor 502 is transmitted using the subcarrier.

As described above, according to the configuration and operation of the mobile communication system in this embodiment, it is possible to improve the reception quality at the mobile station.

Further, according to the mobile communication system of this embodiment, the base station 501 receives the retransmission request signal assigned by the spreading code from the mobile station 511, so that the base station 501 does not collide with the retransmission request signal. Even in the case of occurrence, it is possible to detect which number packet requires which retransmission using the subcarrier by obtaining the correlation value of the spreading code. Then, the packet with the largest number of retransmission requests is retransmitted using the subcarrier with the largest number of requests (subcarrier with the maximum reception quality), so that the mobile station can receive the packet with the required reception quality requested for retransmission. . As a result, it is possible to reduce the number of repeated retransmission requests from the mobile station and improve the throughput.

The present embodiment is applicable to a mobile station that functions as a relay station instead of the base station, assuming a multi-hop connection. In this case, the mobile station 511, which is the transmission source of the retransmission request, has previously recognized the presence of surrounding mobile stations that are relay stations, and the retransmission is performed by designating the transmission path including the mobile station (relay station). Request. Similarly,
The base station 501, which is the transmission source of the signal according to the retransmission request,
Knowing in advance the presence of surrounding mobile stations that are relay stations,
It responds to the retransmission request by designating the transmission path including the mobile station (relay station).

In each of the above embodiments, the mobile station 311,
411,511 reception quality measuring instruments 316, 416, 51
The reception quality measuring function 6 corresponds to the reception quality measuring means, and the reception quality transmitting function of the transceivers 312, 412, 512 corresponds to the reception quality notifying means.

The transmission functions of the transceivers 303, 403 and 503 of the base stations 301, 401 and 501 correspond to the transmission means, and the channel determination functions of the channel determiners 306, 406 and 506 correspond to the wireless channel determination means and the It corresponds to the first, second, and third channel number determining means. Further, the transmission power calculation functions of the channel determiners 306, 406, 506 correspond to the first and second wireless channel transmission power determining means, respectively.

The embodiment of the present invention described above can of course take various modifications. Such modifications have been made so as not to deviate from the spirit and purpose of the present invention, and the following claims are technical contents intended to include all the modifications described above.

[0173]

According to the present invention, based on the reception quality of the signal measured by the mobile station, the reception quality is relatively good, from at least one antenna of the base station,
A signal addressed to the mobile station is transmitted. Therefore, the reception quality of the signal at the mobile station is improved. By this means, it is possible to prevent repeated requests for retransmission from the mobile station and improve throughput.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a mobile communication system in a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a cooperative operation of the mobile communication system with an automatic retransmission request according to the first embodiment of the present invention.

FIG. 3 (a) is a diagram for explaining a state of data transmission when the TDM method is applied, and FIG.
FIG. 6 is a diagram for explaining a data transmission state when the CDM method is applied.

FIG. 4 is a block configuration diagram of a mobile communication system according to a second embodiment of the present invention.

[Fig. 5] Fig. 5 is a diagram for explaining a cooperative operation of the mobile communication system with an automatic retransmission request in the second embodiment of the present invention.

FIG. 6 is a block diagram of a mobile communication system of a third embodiment to which the signal transmission method of the present invention is applied.

FIG. 7 is a flowchart showing an operation of the third exemplary embodiment of the present invention.

FIG. 8 is a block diagram of a mobile communication system of a fourth embodiment to which the signal transmission method of the present invention is applied.

FIG. 9 is a flowchart showing an operation of the fourth exemplary embodiment of the present invention.

FIG. 10 is a flowchart showing a processing procedure for determining a frequency channel number and transmission power of the frequency channel according to the fourth embodiment of the present invention.

FIG. 11 is a diagram showing an example of reception quality of each frequency channel in each mobile station in the fourth embodiment of the present invention.

FIG. 12 is a block diagram of a mobile communication system of a fifth embodiment to which the signal transmission method of the present invention is applied.

FIG. 13 is a block diagram of a conventional mobile communication system.

[Fig. 14] Fig. 14 is a diagram for explaining a cooperative operation of a conventional mobile communication system with an automatic repeat request.

FIG. 15 is a block diagram of a conventional mobile communication system in which an automatic repeat request is made.

FIG. 16 is a diagram for explaining the operation of the conventional mobile communication system.

[Explanation of symbols]

4 ... Transmit / receive demultiplexer, 5 ... Receiver, 6 ... Data input terminal, 7 ...
Base station first antenna, 8 ... Base station second antenna, 15 ...
Transmitter, 16 ... Transmit / receive duplexer, 17 ... Mobile station antenna, 1
00 ... Mobile communication system, 101 ... Base station, 102 ...
ARQ processor, 103 ... Transmitter, 111 ... Mobile station, 11
3 ... ARQ processor, 118 ... Reception quality measuring instrument, 119 ...
memory

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shiro Kikuchi             2-11-1, Nagatacho, Chiyoda-ku, Tokyo Stock             Ceremony company NTT Docomo F-term (reference) 5K014 AA01 BA06 DA02 FA03 FA11                       HA10                 5K067 AA01 AA26 BB02 BB21 CC24                       DD11 DD34 DD45 DD51 EE02                       EE10 FF02 JJ11 JJ37 KK03

Claims (71)

[Claims] 1. A mobile communication system comprising a mobile station and a base station, which transmits and receives a signal while making an automatic retransmission request, wherein the mobile station measures the reception quality of a radio signal transmitted from the base station. And a request transmitting means for transmitting to the base station a radio resource use request for requesting the use of a radio resource that matches the reception quality, based on the reception quality of the measured radio signal, The base station is a request receiving unit that receives the radio resource use request, and the mobile station that includes a signal that is requested to be retransmitted by the automatic retransmission request, using the radio resource requested by the radio resource use request. A mobile communication system, comprising: a signal transmitting unit that transmits the signal. 2. The mobile communication system according to claim 1, wherein the signal transmitting means transmits signals by using radio resources in the descending order of the number of retransmission requests from mobile stations. 3. The reception quality is reception power, or (formula 1) C / (I + N) C: carrier power I: interference power N: noise power or (formula 2) S / (I + N) S: signal power. I: interference power N: noise power or (Equation 3) C / N C: carrier power N: noise power (Equation 4) S / NS: signal power N: noise power or error rate, or likelihood obtained at error decoding Degree, or the base station transmission power value, or the increase or decrease amount of the base station transmission power, or the correlation value obtained by despreading the spreading code,
The mobile communication system according to claim 1, wherein a combination of these is used. 4. The radio resource according to claim 1, wherein at least one antenna, directivity of at least one antenna, a radio channel, a transmission path, or a combination thereof is used as the radio resource. Mobile communication system. 5. A mobile communication comprising a mobile station and a base station having a plurality of antennas, and performing signal transmission / reception control including signal retransmission control by the base station based on an automatic retransmission request from the mobile station. In the system, the mobile station is a quality measuring unit that measures the reception quality of signals transmitted from a plurality of antennas of the base station, and based on the reception quality of the signals from each antenna obtained by measurement, Among the plurality of antennas, a request transmission unit that transmits to the base station an antenna use request to request transmission of a signal from at least one antenna, the base station, at least among the plurality of antennas, Request receiving means for receiving an antenna use request for requesting transmission of a signal from one antenna, and an antenna requested by the antenna use request,
A mobile communication system comprising: a signal transmitting unit that transmits a signal addressed to the mobile station, which includes a signal requested to be retransmitted by the automatic retransmission request. 6. A mobile configured to include a plurality of mobile stations and a base station having a plurality of antennas, and performing signal transmission / reception control including signal retransmission control by the base station based on an automatic retransmission request from the mobile station. A body communication system, wherein the mobile station is based on quality measurement means for measuring reception quality of signals transmitted from a plurality of antennas of the base station, and reception quality of signals from each antenna obtained by measurement. A plurality of antennas, and a request transmitting unit that transmits an antenna use request for requesting transmission of a multicast signal from at least one antenna to the base station, wherein the base station includes the plurality of antennas. Request receiving means for receiving an antenna use request for requesting transmission of a multicast signal from at least one antenna, and the antenna use request From the antenna requested by
A mobile communication system, comprising: a multicast signal transmitting means for transmitting a multicast signal addressed to the mobile station, the multicast signal including a multicast signal requested to be retransmitted by the automatic retransmission request. 7. The multicast signal transmitting means, when antenna use requests from a plurality of mobile stations exist over a plurality of antennas, transmit the multicast signals using the antennas in descending order of the number of requests. The mobile communication system according to claim 6. 8. The request receiving means, when receiving the antenna use request, performs antenna reception by a diversity method.
Or the mobile communication system according to item 6. 9. The quality measuring means is a synchronization signal, a broadcast information signal, an individual signal to a mobile station, a multicast signal, or two or more of these signals transmitted from at least one antenna of the base station. The mobile communication system according to any one of claims 5 to 8, wherein the reception quality is measured by using a combination of. 10. The reception quality is a value obtained by dividing carrier power by the sum of reception power, interference power and noise power, and a value obtained by dividing signal power by the sum of interference power and noise power. , Error rate, likelihood obtained during error correction decoding, C / N ratio, S / N ratio, correlation value obtained by despreading of spreading code, or a combination of two or more of these. The mobile communication system according to any one of claims 5 to 9. 11. A retransmission control of a signal by a base station, which is executed in a mobile communication system configured to include a mobile station and a base station provided with a plurality of antennas, based on an automatic retransmission request from the mobile station. A mobile communication method for performing signal transmission / reception control, comprising: in the mobile station, a quality measurement step of measuring reception quality of signals transmitted from a plurality of antennas of the base station; and in the mobile station, Request transmission for transmitting an antenna use request to the base station to request transmission of a signal from at least one of the plurality of antennas based on the reception quality of the signal from each antenna obtained by measurement A request receiving step of receiving an antenna use request to request transmission of a signal from at least one antenna of the plurality of antennas in the base station; And a signal transmitting step of transmitting a signal addressed to the mobile station including a signal requested to be retransmitted by the automatic retransmission request from the antenna requested by the antenna use request. 12. A re-transmission of a signal by a base station based on an automatic re-transmission request from the mobile station, which is executed in a mobile communication system including a plurality of mobile stations and a base station having a plurality of antennas. A mobile communication method for performing signal transmission / reception control including control, in the mobile station, a quality measuring step of measuring reception quality of signals transmitted from a plurality of antennas of the base station, and the mobile station. , Transmitting an antenna use request to the base station to request transmission of a multicast signal from at least one of the plurality of antennas based on the reception quality of the signal from each antenna obtained by the measurement And a request for antenna use to request transmission of a multicast signal from at least one of the plurality of antennas at the base station. A request receiving step of receiving, and a multicast signal for transmitting a multicast signal addressed to the mobile station including a multicast signal requested to be retransmitted by the automatic retransmission request from the antenna requested by the antenna use request at the base station. A mobile communication method comprising: a transmitting step. 13. In the multicast signal transmitting step, when there are antenna use requests from a plurality of mobile stations over a plurality of antennas, the base station transmits the multicast signals using the antennas in descending order of the number of requests. The mobile communication method according to claim 12. 14. The mobile communication method according to claim 11, wherein, in the request receiving step, when the base station receives the antenna use request, the base station performs antenna reception by a diversity method. 15. In the quality measuring step, the mobile station transmits a synchronization signal, a broadcast information signal, an individual signal to a mobile station, a multicast signal, or a signal transmitted from at least one antenna of the base station. The mobile communication method according to any one of claims 11 to 14, wherein the reception quality is measured by using a combination of two or more of the above. 16. The reception quality is a value obtained by dividing the carrier power by the sum of the reception power, the interference power and the noise power, and a value obtained by dividing the signal power by the sum of the interference power and the noise power. , Error rate, likelihood obtained during error correction decoding, C / N ratio, S / N ratio, correlation value obtained by despreading of spreading code, or a combination of two or more of these. The mobile communication method according to any one of claims 11 to 15. 17. A mobile station comprising a plurality of antennas and moving together with a mobile station that requests transmission of a signal from at least one of the plurality of antennas based on reception quality of signals transmitted from the plurality of antennas. A base station that configures a body communication system and performs signal transmission / reception control, including signal retransmission control based on an automatic retransmission request from the mobile station, with the mobile station, at least among the plurality of antennas. Request receiving means for receiving an antenna use request to request transmission of a signal from one antenna, and the movement including a signal requested to be retransmitted by the automatic retransmit request from the antenna requested by the antenna use request. And a signal transmitting unit that transmits a signal addressed to the station. 18. A plurality of mobile stations comprising a plurality of antennas and requesting transmission of a multicast signal from at least one of the plurality of antennas based on the reception quality of signals transmitted from the plurality of antennas. A base station that configures a mobile communication system with the mobile station and performs signal transmission / reception control including retransmission control of a multicast signal based on an automatic retransmission request from the mobile station, the base station including the plurality of antennas. Request receiving means for receiving an antenna use request for requesting transmission of a multicast signal from at least one antenna, and an antenna requested by the antenna use request, and a retransmission request by the automatic retransmission request. Multicast signaling for transmitting a multicast signal addressed to the mobile station including a multicast signal And a base station. 19. The multicast signal transmitting means comprises:
19. The base station according to claim 18, wherein when there are antenna use requests from a plurality of mobile stations over a plurality of antennas, the multicast signals are transmitted using the antennas in descending order of the number of requests. 20. The base station according to claim 17, wherein the request receiving unit, when receiving the antenna use request, performs antenna reception by a diversity method. 21. Retransmission control of a signal based on an automatic retransmission request, between a base station having a plurality of antennas and transmitting a signal based on a signal transmission request from at least one of the plurality of antennas. A mobile station that performs signal transmission / reception control, including quality measuring means for measuring reception quality of signals transmitted from a plurality of antennas of the base station, and based on reception quality of signals from each antenna obtained by measurement. And a request transmitting means for transmitting to the base station an antenna use request to request transmission of a signal from at least one of the plurality of antennas. 22. Retransmission of a multicast signal based on an automatic retransmission request between a base station having a plurality of antennas and transmitting a multicast signal based on a signal transmission request from at least one of the plurality of antennas. A mobile station that performs signal transmission / reception control including control, quality measuring means for measuring reception quality of signals transmitted from a plurality of antennas of the base station, and reception quality of signals from each antenna obtained by measurement. Based on the above, the mobile station comprising: a request transmitting unit that transmits to the base station an antenna use request for requesting transmission of a multicast signal from at least one of the plurality of antennas. 23. The quality measuring means is a synchronization signal transmitted from at least one antenna of the base station, a signal of broadcast information, an individual signal to a mobile station, a multicast signal, or two or more of these. The mobile station according to claim 21 or 22, wherein the reception quality is measured by using a combination of 24. The reception quality is a value obtained by dividing the carrier power by the sum of the reception power, the interference power and the noise power, and a value obtained by dividing the signal power by the sum of the interference power and the noise power. , Error rate, likelihood obtained during error correction decoding, C / N ratio, S / N ratio, correlation value obtained by despreading of spreading code, or a combination of two or more of these. The mobile station according to any one of claims 21 to 23. 25. A signal transmission method in a mobile communication system, comprising a mobile station and a base station, for transmitting and receiving a signal while making an automatic retransmission request, wherein the mobile station is configured to transmit a radio signal transmitted from the base station. The reception quality is measured, and the reception quality of the measured radio signal is notified to the base station, and the base station transmits the signal for which retransmission is requested from the mobile station based on the notified reception quality to the mobile station. A signal transmission method in a mobile communication system in which transmission is performed so as to meet the required reception quality of a station. 26. The signal transmission method according to claim 25, wherein the radio signal transmitted from the base station is a plurality or a single radio channel in a mobile communication system. 27. The signal transmission method according to claim 26, wherein among the plurality or single radio channels transmitted from the base station, a broadcast information channel, a dedicated channel, a multicast channel, or a combination thereof is moved. A signal transmission method in a mobile communication system used by a station as a radio channel for measuring reception quality. 28. The signal transmitting method according to claim 27, wherein the reception quality is reception power, or (formula 1) C / (I + N) C: carrier power I: interference power N: noise power or (formula 2). S / (I + N) S: Signal power I: Interference power N: Noise power or (Equation 3) C / N C: Carrier power N: Noise power (Equation 4) S / NS: Signal power N: Noise power or error A signal transmission method in a mobile communication system in which a rate, a likelihood obtained at the time of error decoding, a base station transmission power value, an increase amount or an attenuation amount of the base station transmission power, or a combination thereof is used. 29. The signal transmitting method according to claim 26, wherein the radio channel transmitted and received between the base station and the mobile station is a subcarrier channel, an orthogonal subcarrier channel, a frequency channel, or a different frequency. A signal transmission method in a mobile communication system, which is at least one of frequency channels in a band. 30. The signal transmission method according to claim 25, wherein when the mobile station needs a retransmission request for the received signal, the mobile station transmits the retransmission request together with the measured reception quality of the radio signal to the base station. A signal transmission method in a mobile communication system for notifying a station. 31. The signal transmission method according to claim 25, wherein when the mobile station notifies the base station of arrival confirmation of a received signal, the measured reception quality of the plurality of or single radio channels. A method of transmitting a signal in a mobile communication system for notifying the base station of 32. The signal transmitting method according to claim 30, wherein the mobile station has a plurality of or a single radio channel number,
A signal transmission method in a mobile communication system, which notifies a base station of only the reception quality of the radio channel or the channel number of the reception quality within a predetermined range as the reception quality of the measured or single radio channel. 33. The signal transmission method according to claim 30 or 31, wherein the number of a plurality of or a single radio channel that has obtained a required reception quality including a reception quality with which the reception quality at the mobile station is maximum, A signal transmission method in a mobile communication system, which notifies the base station together with the obtained reception quality. 34. The signal transmission method according to claim 30, wherein the base station obtains a radio channel that satisfies the required reception quality of the mobile station based on the notification from the mobile station, and determines the obtained radio channel. A method of transmitting a signal in a mobile communication system, which uses the mobile station to transmit a signal of which retransmission is requested. 35. The signal transmitting method according to claim 34, wherein, even after the base station transmits the signal requested to be retransmitted by the mobile station through the obtained wireless channel, the base station responds to a signal addressed to the mobile station. Is a signal transmission method in a mobile communication system for transmitting using the obtained wireless channel. 36. The signal transmitting method according to claim 34, wherein the base station satisfies a required reception quality at the mobile station based on a notification from the mobile station, and transmits from the base station. A signal transmission method in a mobile communication system for determining the number of a radio channel to be transmitted so that the power has a predetermined value and the transmission power of the radio channel. 37. The signal transmitting method according to claim 36, wherein when the base station transmits the same multicast signal to a plurality of mobile stations, based on a notification from each mobile station,
The transmission power of a plurality of or a single radio channel and the transmission power of the radio channel for transmitting the multicast signal so that the required reception quality at each mobile station is satisfied and the transmission power from the base station becomes a predetermined value. A method for transmitting a signal in a mobile communication system to determine. 38. The signal transmitting method according to claim 37, wherein the base station, when transmitting the same multicast signal to a plurality of mobile stations, has a reception quality channel within a predetermined range notified from each mobile station. A signal transmission method in a mobile communication system for obtaining a number of a radio channel that can be considered to have a large number of retransmission requests from mobile stations. 39. A mobile communication system comprising a mobile station and a base station for transmitting and receiving signals while making an automatic retransmission request, wherein the mobile station measures the reception quality of a radio signal transmitted from the base station. And a reception quality notifying unit for notifying the base station of the reception quality of the measured radio signal, wherein the base station notifies the mobile station of a signal requested to be retransmitted by the mobile station. A mobile communication system comprising a transmitting means for transmitting the mobile station so as to satisfy a required reception quality based on the received quality. 40. The mobile communication system according to claim 39, wherein the reception quality measuring unit measures reception quality of a plurality of or a single radio channel transmitted from a base station. 41. The mobile communication system according to claim 40, wherein the reception quality measuring unit selects a broadcast information channel, a dedicated channel, a multicast channel, or a plurality of single radio channels transmitted from the base station. A mobile communication system using a combination of these as a radio channel for measuring the reception quality by the mobile station. 42. The mobile communication system according to claim 40, wherein the reception quality is reception power, or (Equation 1) C / (I + N) C: carrier power I: interference power N: noise power or (Equation 2) S / (I + N) S: Signal power I: Interference power N: Noise power or (Equation 3) C / N C: Carrier power N: Noise power (Equation 4) S / N S: Signal power N: A mobile communication system in which a noise power or an error rate, a likelihood obtained at the time of error decoding, a base station transmission power value, an increase amount or an attenuation amount of the base station transmission power, or a combination thereof is used. 43. The mobile communication system according to claim 40 or 41, wherein a radio channel transmitted and received between the base station and the mobile station is a subcarrier channel, an orthogonal subcarrier channel, a frequency channel, or a different channel. A mobile communication system which is at least one of frequency channels in a frequency band. 44. The mobile communication system according to claim 39, wherein the reception quality notifying unit, together with the measured reception quality of the wireless signal, requests the retransmission when a retransmission request for the received signal is required. A mobile communication system for notifying the base station. 45. The mobile communication system according to claim 39, wherein when the reception quality notifying means notifies the base station of arrival confirmation of a received signal, the measured multiple or single radio channel. Mobile communication system for notifying the base station of the reception quality of. 46. The mobile communication system according to claim 44 or 45, wherein said reception quality notifying means is a plurality or a single radio channel number, and the reception quality of said radio channel or a reception quality within a predetermined range. A mobile communication system for notifying the base station of only the channel number of the above as the reception quality of the measured plural or single radio channels. 47. The mobile communication system according to claim 44 or 45, wherein the reception quality notifying unit obtains required reception quality including reception quality that maximizes reception quality at the mobile station. A mobile communication system for notifying the base station of the number of one radio channel together with the obtained reception quality. 48. The mobile communication system according to claim 44, wherein the base station determines a radio channel that satisfies the required reception quality of the mobile station based on a notification from the mobile station, A mobile communication system comprising: a transmitting unit that transmits a signal of which retransmission is requested from the mobile station using the wireless channel obtained by the wireless channel determining unit. 49. The mobile communication system according to claim 48, wherein the transmitting unit responds to a signal addressed to the mobile station even after transmitting a signal requested to be retransmitted by the mobile station through the obtained wireless channel. In particular, a mobile communication system that transmits using the determined wireless channel. 50. The mobile communication system according to claim 48, wherein the base station satisfies a required reception quality at the mobile station based on a notification from the mobile station, and transmits from the base station. Mobile unit comprising first wireless channel number determining means for determining the number of a wireless channel to be transmitted so that the power has a predetermined value, and first wireless channel transmission power determining means for determining the transmission power of the wireless channel Mobile communication system in a communication system. 51. The mobile communication system according to claim 50, wherein when the base station transmits the same multicast signal to a plurality of mobile stations, based on a notification from each mobile station,
A second radio channel that determines the number of a plurality or a single radio channel that transmits the multicast signal so that the required reception quality at each mobile station is satisfied and the transmission power from the base station becomes a predetermined value. A mobile communication system comprising a number determining means and a second wireless channel transmission power determining means for determining the transmission power of the wireless channel. 52. The mobile communication system according to claim 51, wherein when the base station transmits the same multicast signal to a plurality of mobile stations, the reception quality within a predetermined range notified from each mobile station is received. A mobile communication system comprising third wireless channel number determining means for determining a wireless channel number that can be regarded as having a large number of retransmission requests from mobile stations among channel numbers. 53. The mobile communication system according to claim 39, wherein the base station determines, based on a notification from the mobile station, a radio resource determining unit that determines a radio resource that satisfies the required reception quality of the mobile station, A mobile communication system comprising: a signal transmitting unit that transmits a signal whose retransmission is requested from the mobile station using the radio resource obtained by the radio resource determining unit. 54. The mobile communication system according to claim 39, wherein said transmitting means transmits signals by using radio resources in the order of increasing number of retransmission requests from mobile stations. 55. The radio resource according to claim 53, wherein at least one antenna, directivity of at least one antenna, a radio channel, a transmission path, or a combination thereof is used as the radio resource. Mobile communication system. 56. A base station in a mobile communication system, comprising a mobile station and a base station, for transmitting and receiving a signal while making an automatic retransmission request, wherein the base station transmits a signal for which a retransmission request is made from the mobile station. A base station comprising a transmitting unit that transmits so that the mobile station satisfies a required reception quality based on the reception quality notified from the mobile station. 57. The base station according to claim 56, wherein the base station determines a radio channel that satisfies the required reception quality of the mobile station based on a notification from the mobile station, and the radio channel. A base station comprising: a transmitting unit that transmits a signal whose retransmission is requested from the mobile station using the wireless channel obtained by the determining unit. 58. The base station according to claim 56 or 57, wherein the transmitting unit outputs a signal addressed to the mobile station even after transmitting the signal requested to be retransmitted by the mobile station through the obtained wireless channel. On the other hand, a base station that transmits using the obtained wireless channel. 59. The base station according to any one of claims 56 to 58, wherein the base station satisfies a required reception quality at the mobile station based on a notification from the mobile station, and First wireless channel number determining means for determining the number of a wireless channel to be transmitted so that the transmission power from the base station becomes a predetermined value, and first wireless channel transmission power for determining the transmission power of the wireless channel. A base station comprising a determining means. 60. The base station according to claim 56, wherein the base station is based on a notification from each mobile station when transmitting the same multicast signal to a plurality of mobile stations. hand,
A second radio that determines the number of a plurality of or a single radio channel for transmitting the multicast signal so that the required reception quality at each mobile station is satisfied and the transmission power from the base station becomes a predetermined value. A base station comprising channel number determining means and second wireless channel transmission power determining means for determining transmission power of the wireless channel. 61. The base station according to claim 56, wherein when the base station transmits the same multicast signal to a plurality of mobile stations, the base station notifies the mobile station of the predetermined multicast signal. A base station comprising a third radio channel number determining means for obtaining a radio channel number which can be regarded as having a large number of retransmission requests from mobile stations, out of channel numbers of reception quality within the range. 62. The base station according to claim 56, wherein the radio channel used by the base station with the mobile station is a subcarrier channel, an orthogonal subcarrier channel, a frequency channel, or a frequency in a different frequency band. A base station that is at least one of the channels. 63. A mobile station in a mobile communication system, comprising a mobile station and a base station, for transmitting and receiving a signal while making an automatic retransmission request, wherein the mobile station receives a radio signal transmitted from the base station. A mobile station comprising: reception quality measuring means for measuring quality; and reception quality notifying means for notifying the base station of the measured reception quality of the radio signal. 64. The mobile station according to claim 63, wherein the reception quality measuring means measures the reception quality of a plurality of or a single radio channel transmitted from the base station. 65. The mobile station according to claim 63 or 64, wherein the reception quality measuring unit selects a broadcast information channel, a dedicated channel, or a multicast channel from a plurality of or a single radio channel transmitted from the base station. Alternatively, a mobile station that uses a combination of these as a radio channel for measuring reception quality by the mobile station. 66. The mobile station according to claim 63 or 65, wherein the reception quality is reception power, or (formula 1) C / (I + N) C: carrier power I: interference power N: noise power or (formula). 2) S / (I + N) S: Signal power I: Interference power N: Noise power or (Equation 3) C / N C: Carrier power N: Noise power (Equation 4) S / N S: Signal power N: Noise power A mobile station that has an error rate, a likelihood obtained at the time of error decoding, a base station transmission power value, an increase amount or an attenuation amount of the base station transmission power, or a combination thereof. 67. The mobile station according to claim 63, wherein the reception quality notifying unit measures the reception quality of the measured radio signal when a retransmission request for the received signal is required. At the same time, a mobile station that notifies the base station of the retransmission request. 68. The mobile station according to any one of claims 63 to 67, wherein the reception quality notifying unit, when notifying the base station of arrival confirmation of a received signal, measures the plurality of measured values or A mobile station that notifies the base station of the reception quality of a single radio channel. 69. The mobile station according to claim 63 or 68, wherein the reception quality notifying means is a plurality of or a single radio channel number and a reception quality of the radio channel or a reception quality channel within a predetermined range. A mobile station that notifies the base station of only the number as the reception quality of the measured multiple or single radio channel. 70. The mobile station according to claim 63 or 69, wherein the reception quality notifying unit obtains required reception quality including reception quality that maximizes reception quality at the mobile station. A mobile station that notifies the base station of the number of the radio channel together with the obtained reception quality. 71. The mobile station according to claim 63 or 70, wherein the radio channel used by the mobile station with the base station is a subcarrier channel, an orthogonal subcarrier channel, a frequency channel, or a frequency in a different frequency band. A mobile station that is at least one of the channels.