RU2454003C2 - Transmitting apparatus, receiving apparatus and data transmitting method - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: disclosed invention relates to a transmitting apparatus, a receiving apparatus and a data transmitting method. To this end, measurement of communication quality using a broadband signal and transmitting and receiving data using a predetermined frequency band is carried out at approximately the same time. The transmitting apparatus (1) can transmit data at a first frequency and a second frequency to the receiving apparatus (2). The transmitter (1a) of the transmitting apparatus (1) transmits a predetermined broadband signal in a first period of time in a frequency band which does not include the first frequency, and in a second period of time in a frequency band which does not include the second frequency. The quality measuring unit (2a) of the receiving apparatus (2) measures quality of communication with the transmitting apparatus (1) based on the broadband signal received in the first and second period of time.

EFFECT: invention helps prevent quality deterioration when transmitting and receiving data.

14 cl, 21 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a transmission device, a reception device and a data transmission method, and more particularly, to a transmission device capable of transmitting and receiving data using a plurality of frequencies, a receiving device and a data transmission method.

State of the art

Currently, in the field of mobile communication systems, communication systems use CDMA (Code Division Multiple Access) as a multiple access scheme during operation. On the other hand, research on next-generation mobile communication systems was very active, aimed at faster wireless data transfer. For example, 3GPP (Third Generation Partnership Project), which is developing standards for third-generation mobile communications systems, is working to standardize new specifications for mobile communications systems called LTE (Long Term Evolution) (for example, see Non-Patent Literature 1).

Next-generation mobile communication systems are believed to use OFDMA (Orthogonal Frequency Division Multiple Access) or SC-FDMA (Single Carrier Frequency Division Multiple Access) as a multiple access scheme. Such mobile communication systems schedule uplink data transmission from the mobile station to the base station as follows.

When the mobile station has control information and other data for transmission, the base station dynamically allocates radio resources in both the frequency domain and the time domain for the uplink data channel. The base station then provides the mobile station with the result of the allocation of radio resources. According to this result, the mobile station transmits control information and other data both at a distributed frequency and at distributed time intervals.

When the mobile station has only control information for transmission, on the other hand, resources for the uplink data channel are not allocated to the mobile station and it transmits control information to the base station via the uplink control channel, which is a radio resource predetermined for transmission management information. The control information that is transmitted on the uplink includes ACK (Acknowledgment) / NACK (Negative acknowledgment), which is a response to data from the base station, and CQI (Channel Quality Indicator), which is a measure of the quality of downlink communication (e.g. see Non-Patent Literature 2).

Incidentally, the base station preferably allocates a frequency range with the best uplink communication quality for the uplink data channel from the available frequency band between the base station and the mobile station. Therefore, before resources are allocated for the uplink data channel, the mobile station needs to transmit to the base station a wideband pilot (SRS: Sounding the Reference Signal), which is used to measure the quality of the uplink communication. In this case, the problem arises of how to multiplex control information and SRS when the same or different mobile stations transmit them simultaneously. To solve this problem, the following multiplexing scheme was proposed (for example, see Non-Patent Literature 3).

21 illustrates an example of uplink signals including SRS. In this example, according to FIG. 21, an ACK is transmitted as control information with two frequency bands as uplink control channels i and j. The mobile station is allowed to use one of these uplink control channels i and j to transmit control information. For each uplink control channel, a signal indicating control information and a pilot signal (RS (Reference Signal)) are scheduled in a predetermined order. However, in a predetermined portion of the time unit period, all frequency ranges are reserved as radio resources for SRS transmission. When transmitting SRS, the mobile station uses the reserved resource in a predetermined portion of the time unit period.

Non-Patent Literature 1: 3rd Generation Partnership Project, "Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access (E-UTRAN); Overall description: Stage 2 (Release 8)", 3GPP TS36.300, 2007- 06, V8.1.0.

Non-Patent Literature 2: 3rd Generation Partnership Project, "Physical Channels and Modulation (Release 8)", 3GPP TS36.211, 2007-05, VI.1.0.

Non-Patent Literature 3: 3rd Generation Partnership Project, "Multiplexing of Sounding RS and PUCCH", 3GPP TSG-RAN WG1 # 49bis Rl-072756, 2007-6.

Problems to be Solved by the Invention

However, the time multiplexing scheme used in Non-Patent Literature 3 does not permit the transmission of control information at the same time as a broadband signal, which should be used to measure communication quality. Therefore, in comparison with the case of non-multiplexing a broadband signal and a control information signal, this circuit provides fewer radio resources available in each period of time for each channel of the uplink. This causes problems in that the reception quality of a signal indicating the control information is degraded in the reception device (corresponding to the above-described base station on the uplink), and in that the number of transmission devices (corresponding to the above-described mobile station on the uplink) can be covered by each control channel is reduced.

The present invention has been made in view of the foregoing description and is intended to provide a transmission device, a reception device and a data transmission method that can prevent deterioration in the quality of data transmission and reception, even when measuring the quality of communication using a broadband signal, and transmitting and receiving data using a predetermined frequency range performed at the same time.

Problem Solver

In order to solve the above problems, the present invention provides a transmission device illustrated in FIG. 1. The transmission device 1 is capable of performing both data transmission on a first frequency and data transmission on a second frequency. The transmission device 1 includes a transmitter 1a, which transmits a signal that should be used by the transmission device 2 to measure the quality of communication in a given part of the first time period in a frequency range that has a wider frequency band than that used for data transmission, and does not include the first frequency, and transmits a signal in a given part of the second period of time that comes after the first time period, in a frequency range that has a wider frequency band than that which uses tsya for data transmission, and does not include the second frequency.

With such a transmission device 1, a signal to be used to measure communication quality is transmitted in a predetermined portion of a first time period in a frequency range that has a wider frequency band than that for data transmission and does not include a first frequency. Then, the signal that should be used to measure the quality of communication is transmitted in a predetermined part of the second time period after the first time period, in a frequency range that has a wider frequency band than that for data transmission, and does not include a second frequency.

Further, in order to solve the above problems, a reception device illustrated in FIG. 1 is provided. The receiving device 2 is intended for communication with the transmission device 1, which is capable of performing both data transmission on the first frequency and data transmission on the second frequency. The receiving device 2 includes a quality measuring unit 2a that measures the quality of communication with the transmission device 1 based on a signal transmitted in a predetermined portion of a first time period in a frequency range that has a wider frequency band than that used for data transmission, and does not include the first frequency, and based on the signal transmitted in a given part of the second period of time that comes after the first time period, in a frequency range that has a wider frequency band than that which used for data transmission, and does not include the second frequency.

Such a receiving device 2 can measure the quality of communication with the transmission device 1 based on a signal transmitted in a predetermined part of the first time period in a frequency range that has a wider frequency band than that for data transmission and does not include the first frequency, and a signal transmitted in a predetermined part of a second time period after the first time period in a frequency range that has a wider frequency band than that for data transmission and does not include a second frequency.

Advantages of the Invention

According to the present invention, a signal to be used to measure communication quality is transmitted in a first time period in a frequency range that does not include a first frequency, and then transmitted in a second time period in a frequency range that does not include a second frequency. Therefore, there is a frequency range without interference from this signal in each of the first and second time periods. This can prevent degradation in data transmission and reception. In addition, the use of a signal transmitted in the first time period and transmitted in the second time period makes it possible to measure the quality of a wide frequency range.

The above and other objects, features, and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings, which illustrate preferred embodiments of the present invention by way of example.

Brief Description of the Drawings

1 illustrates an overview of an embodiment.

2 illustrates a configuration of a system according to an embodiment.

FIG. 3 is a block diagram illustrating functions of a mobile station according to a first embodiment.

4 is a block diagram illustrating the functions of a base station.

5 illustrates a frame structure.

6 illustrates a downlink channel allocation.

7 illustrates an uplink channel allocation.

FIG. 8 illustrates an example of uplink signals including ACKs according to the first embodiment.

FIG. 9 illustrates an example of uplink signals including CQIs according to the first embodiment.

10 illustrates another example of uplink signals including ACKs according to the first embodiment.

11 illustrates another example of uplink signals including CQIs according to the first embodiment.

12 is a sequence diagram illustrating distribution control in a case where SRS and uplink data are superimposed.

13 is a sequence diagram illustrating distribution control in the case where the SRS and ACK overlap.

14 illustrates an example of uplink signals including ACKs according to a second embodiment.

15 illustrates an example of uplink signals including CQIs according to a second embodiment.

FIG. 16 is a block diagram illustrating functions of a mobile station according to a third embodiment. FIG.

FIG. 17 illustrates an example of uplink signals including ACKs according to a third embodiment.

FIG. 18 illustrates an example of uplink signals including CQIs according to a third embodiment.

FIG. 19 illustrates another example of uplink signals including ACKs according to a third embodiment.

FIG. 20 illustrates another example of uplink signals including CQIs according to a third embodiment.

21 illustrates an example of uplink signals including SRS.

The best mode for implementing the invention

Hereinafter, embodiments of the present invention are described in detail with reference to the accompanying drawings. The description begins with a review of the embodiment that will be discussed in the present description, and then proceeds to the details of these embodiments.

1 illustrates an overview of an embodiment. The communication system of FIG. 1 is intended for transmitting and receiving data at a plurality of frequencies and includes a transmission device 1 and a receiving device 2.

The transmission device 1 is a data transmission device that transmits data via radio communication to the reception device 2. The transmission device 1, for example, is the equivalent of a mobile station of a mobile telephone system. The transmission device 1 includes a transmitter 1a, which transmits a signal to the reception device 2, which should be used to measure the quality of the radio communication from the transmission device 1 to the reception device 2.

In more detail, the transmitter 1a transmits a broadband signal that occupies a wider frequency range than that used for data transmission, in a given part of the first time period in a frequency range that does not include the first frequency. The transmitter 1a then transmits a broadband signal in a predetermined portion of a second time period following the first time period in a frequency range that does not include a second frequency.

The reception device 2 is a data transmission device that receives data via radio communication from the transmission device 1. The receiving device 2, for example, is the equivalent of a base station of a mobile telephone system. The receiving device 2 includes a quality measuring unit 2a. The quality measuring unit 2a measures the quality of the radio communication from the transmission device 1 to the reception device 2 based on a broadband signal received from the transmission device 1 in the first and second time periods. The measured radio quality can be used as an index to select the frequency range, which, for example, should be allocated to the transmission device 1.

In such a communication system, the transmitter 1a of the transmission device 1 uses a frequency range that does not include a first frequency in a predetermined part of a first time period, and uses a frequency range that does not include a second frequency in a predetermined part of a second time period, for transmitting a broadband signal . Then, the quality measurement unit 2a of the reception device 2 measures the quality of the radio communication from the transmission device 1 to the reception device 2 based on a broadband signal received in the first and second time periods.

In general, measuring communication quality requires a signal over a wide range of frequencies. However, if the transmitted signal occupies all the frequency ranges available for data transmission between the transmission device 1 and the receiving device 2, the transmission and reception of data is prevented (delayed) during this transmission. The aforementioned technique allows the use of at least a first frequency without interference of a broadband signal during a first time period and the use of at least a second frequency without interference of a broadband signal during a second time period.

Therefore, this technique can prevent deterioration in the quality of communication due to a reduction in the period of time available for transmitting and receiving data. Additionally, the receiving device 2 can use a broadband signal received in the first and second time periods, which allow you to measure the quality of a wide range of frequencies.

(First Embodiment)

Below, a first embodiment is described in detail with reference to the accompanying drawings.

2 illustrates a configuration of a system according to an embodiment. A mobile communication system according to an embodiment is a radio data transmission system in which packet data is transmitted. The mobile communication system of FIG. 2 includes mobile stations 100 and 100a and a base station 200.

Mobile stations 100 and 100a, for example, are mobile phones. Being in the communication range (cell) of the base station, the mobile stations 100 and 100a are able to perform radio communications with the base station, transmit and receive packet data from an un illustrated computer or other mobile station using the base station. The packet data that the mobile stations 100 and 100a transmit and receive includes VoIP (Voice over Internet Protocol) data, email data, and image data.

The base station 200 constantly monitors the mobile stations existing in its cell, and performs wired or radio communications with other base stations, where appropriate. After receiving a radio data request (radio) from a mobile station existing in the cell, or a radio data request for communication with a mobile station existing in the cell, the base station 200 transmits and receives various control information and packet data from the mobile station.

FIG. 3 is a block diagram illustrating functions of a mobile station according to a first embodiment. The mobile station 100 includes a transmitting and receiving antenna 110, a data processor 120, a pilot signal processor 130, a control information processor 140, a resource selection unit 150, a transmitter 160, a receiver 170, and a downlink quality measurement unit 180.

The transmitting and receiving antenna 110 is an antenna that is to be used for transmission and reception, and which is intended to transmit via the uplink radio signals output from the transmitter 160 to the base station 200, receiving downlink signals transmitted by radio from the base station 200, and transmitting signals to receiver 170.

The data processor 120 generates packet data to be transmitted by radio, encodes and outputs the data. For example, data processor 120 generates VoIP data, email data, image data, etc. in response to operational inputs from a user of the mobile station 100. The pilot processor 130 generates various types of pilot signals. A coding pattern is defined for each type of pilot. The pilots that the pilot processor 130 generates include an SRS, which should be used to measure uplink communication quality.

The control information processor 140 generates control information to be transmitted by radio, encodes and outputs the information according to prescribed rules. The control information that the control information processor 140 generates includes an ACK / NACK, which is a response to packet data from a base station, a CQI, which is a measurement (measure) of downlink communication quality, an uplink radio resource allocation request, and t .d. More specifically, when a downlink communication quality measurement is supplied from the downlink quality measurement unit 180, the control information processor 140 generates CQI.

The resource selection unit 150 controls uplink radio resources available to the mobile station 100. The resource selection unit 150 from time to time receives control information (UL allocation grant information) from the receiver 170 indicating the uplink radio resource allocated by the base station 200. In addition, a resource selection unit 150 provides the transmitter 160 with radio resource allocation information.

The transmitter 160 identifies radio resources that should be used to transmit packet data, pilot, and control information based on the distribution information provided by the resource selection unit 150. The transmitter 160 then modulates and multiplexes the packet data signal, the pilot signal and the control information signal, outputs the result to the transmitting and receiving antenna 110. This embodiment uses SC-FDMA or OFDMA as the multiplexing circuit.

After receiving the received signals using the transmit and receive antennas 110, the receiver 170 checks the signals to determine if they contain a signal addressed to its own station. If such a signal is detected, the receiver 170 demodulates and decodes the signal. Packet data included in the received signal, if any, is enclosed internally. The mobile station 100 processes the packet data according to their type. For example, in the case of VoIP data, the mobile station 100 outputs sounds from a speaker. In the case of email or image data, the mobile station 100 displays text or images on a display screen.

UL allocation provisioning information included in the received signal, if any; the receiver 170 transmits information to the resource selection unit 150. The receiver 170 also extracts a signal that should be used to measure downlink communication quality from the received signal, and transmits a signal to the downlink quality measurement unit 180.

The downlink quality measurement unit 180 measures the quality of data transmission (communication) of a plurality of downlink frequency ranges based on a signal transmitted from the receiver 170. Then, the downlink quality measurement unit 180 supplies the measurement result to the control information processor 140.

It should be noted that the mobile station 100a can be designed to have the same modular configuration as the mobile station 100.

4 is a block diagram illustrating the functions of a base station. Base station 200 includes a transmit and receive antenna 210, a data processor 220, a pilot processor 230, a control information processor 240, a resource manager 250, a scheduler 260, a transmitter 270, a receiver 280, and an uplink quality measurement unit 290.

The transmit and receive antenna 210 is an antenna for transmitting and receiving. The transmitting and receiving antenna 210 transmits downlink signals output from the transmitter 270 via radio. The transmitting and receiving antenna 210 also receives uplink signals transmitted by radio from the mobile stations 100 and 100a, and transmits them to the receiver 280.

If there is packet data that must be transmitted by radio communication to the mobile station 100, 100a existing in the cell, the data processor 220 encodes and outputs the data. For example, when VoIP data, email data, image data, or other data that is addressed to the mobile station 100, 100a is transmitted, the data processor 220 encodes and outputs the data.

The pilot processor 230 generates various types of pilot signals that allow the mobile station 100, 100a to correctly reproduce the packet data from the radio signals. A coding pattern is defined for each type of pilot.

The control information processor 240 generates control information to be transmitted by radio, encodes and outputs the information according to predetermined rules. The control information that the control information processor 240 generates includes information for demodulation and decoding, such as packet data coding scheme and radio resource used for transmitting packet data, and UL allocation providing information indicating an uplink radio resource distribution.

The resource manager 250 controls the radio resources of the downlink and uplink between the base station 200 and the mobile stations 100 and 100a existing in the cell. The resource manager 250 provides the scheduler 260 and the receiver 230 with information about the current state of the distribution of radio resources. When allocating the uplink radio resource to the mobile station 100, 100a, the resource manager 250 refers to the communication quality measurement results provided from the uplink quality measurement unit 290. The resource manager 250 preferably allocates a frequency band with good communication quality.

Scheduler 260 determines the radio resources to be used for transmitting packet data, pilot, and control information that are addressed to each mobile station based on the current state of the downlink radio resource allocation from the resource manager 250. This embodiment uses OFDMA as a multiplexing scheme.

In accordance with the instructions from the scheduler 260, the transmitter 270 modulates and multiplexes the packet data signal, the pilot signal and the control information signal, outputs the result to the transmitting and receiving antenna 210.

When received signals from the transmitting and receiving antennas 210 are supplied, the receiver 280 demodulates and decodes the signal transmitted from each of the mobile stations 100 and 100a existing in the cell with reference to the uplink radio resource allocation information supplied from the resource manager 250. Packet data included in the received signal, if any, is enclosed internally. Base station 200 transmits the received packet data to its destination computer or mobile station.

If the received signal includes control information requesting a radio resource allocation, then the receiver 280 transmits this information to the resource manager 250. If the received signal includes an SRS, then the receiver 280 transmits the SRS to an uplink quality measurement unit 290.

When SRS is supplied from the receiver 280, the uplink quality measurement unit 290 measures the communication quality of the multiple uplink frequency bands based on the SRS. Then, the uplink quality measurement unit 290 provides the measurement result to the resource manager 250.

5 illustrates a frame structure. 5 schematically depicts the structure of a frame that is transmitted and received between mobile stations 100 and 100a and base station 200. Each frame has a time duration of 10 ms and has many subframes with a duration of 1 ms.

Each subframe is further divided in both the frequency domain and the time domain to control the distribution of radio resources. The minimum block (unit) for distribution on the frequency axis is called the subcarrier, and the minimum block (unit) for distribution on the time axis is called the symbol. The smallest radio resource allocation block, represented by one subcarrier and one symbol, is called a resource element. Thus, the first and second halves of the 1 ms subframe, each of which, therefore, has a duration of 0.5 ms, are called slots, respectively. That is, one subframe has two slots.

Such radio resources are used for uplink and downlink control channels and uplink and downlink data channels. When a signal is transmitted, a guard interval called CP (Cyclic Prefix) is inserted at the beginning of each character to prevent interference between signals due to propagation delay. In the present description, two types of CP prefixes (Short CP and Long CP) are used having different lengths of time.

6 illustrates a downlink channel allocation. 6 schematically depicts the structure of a subframe that is transmitted in a downlink from a base station 200 to mobile stations 130 and 100a. For the downlink, radio resources are allocated for the downlink control channels and the downlink data channels to the mobile stations.

Each downlink control channel is allocated a radio resource having a predetermined symbol length at the beginning of a subframe. In general, one to three characters are allocated first. The frequencies of the downlink control channels for multiple mobile stations are multiplexed. The mobile station 100, 100a detects a downlink control channel for its own station from a plurality of downlink control channels whose frequencies are multiplexed. The downlink control channel is used to transmit information indicating a coding scheme of data included in the downlink data channel, the radio resource used for the downlink data channel, and UL allocation grant information.

Each downlink data channel is allocated a radio resource different from the radio resources used for the downlink control channels. The downlink data channel frequencies for multiple mobile stations are multiplexed. The downlink data channels and the downlink control channels are time multiplexed. The mobile station 100, 100a refers to control information transmitted over the downlink control channel to identify the radio resource of the downlink data channel for the own station. The number of radio resources that should be used for the downlink data channel is variable. The downlink data channel is used to transmit packet data.

The aforementioned downlink control channel may be represented as a PDCCH (physical downlink control channel), while the aforementioned downlink data channel may be represented as a PDSCH (physical downlink shared channel).

7 illustrates an uplink channel allocation. 7 schematically depicts the structure of a subframe that is transmitted in an uplink from mobile stations 100 and 100a to a base station 200. For an uplink, radio resources are allocated to uplink control channels, each of which is shared by a plurality of mobile stations, and data channels uplink communications, each of which is used by one mobile station.

Each uplink control channel is allocated a radio resource of a predetermined frequency range, including one of two limit frequencies, or frequency ranges located at both ends of the transmission range, from the entire frequency range available between the mobile stations 100 and 100a and the base station 200.

In the present description, two uplink control channels are provided for the uplink. One uplink control channel uses a high frequency radio resource in a slot of the first half and a low frequency radio resource in a slot of the second half (represented as an uplink control channel i in FIG. 7). Another uplink control channel uses a low frequency radio resource in the slot of the first half and a high frequency radio resource in the slot of the second half (represented as the uplink control channel j in FIG. 7).

One of the two uplink control channels is allocated to each mobile station 100, 100a through the base station 200. The base station 200 indirectly controls this distribution to the mobile stations 100 and 100a through the downlink control channel allocation for the downlink. More specifically, the uplink control channels are allocated according to the downlink control channel allocation in such a way that the mobile station to which the downlink control channel i is allocated in FIG. 6 uses the uplink control channel i, the mobile station to which the channel is allocated downlink control j, uses the uplink control channel j, and the mobile station to which the downlink control channel k is allocated uses anal i uplink control i.

The uplink control channel is used to transmit ACK / NACK, CQI, and requests distribution of radio resources, etc. For each uplink control channel, control information from a plurality of mobile stations is encoded, multiplexed, and then transmitted. Typically, one uplink control channel allows transmission of control information from six mobile stations. If the base station 200 has many mobile stations, the base station 200 provides protection for a wider range of frequencies for uplink control channels, thereby allowing many mobile stations to transmit control information over the uplink control channels.

A frequency range different from the frequency ranges used for the uplink control channels is allocated to each uplink data transmission channel. The frequencies of the uplink data channels from multiple mobile stations are multiplexed. The mobile station 100, 100a identifies usable radio resource for the uplink data channel based on the UL allocation grant information received on the downlink control channel. The uplink data channel is used to transmit packet data. In addition, the uplink data channel may also be used to transmit control information.

The mobile station 100, 100a determines which one of the uplink control channel and the uplink data channel is suitable for use for transmitting control information based on whether or not the uplink data channel is assigned by the base station 200. More specifically, if an uplink data channel has been assigned, the mobile station 100, 100a uses this uplink data channel to transmit control information together with packet data. In contrast, if no uplink data channel has been assigned, the mobile station 100, 100a uses the uplink control channel to transmit control information.

Incidentally, on the uplink, an SRS, which is a broadband signal, can be transmitted in addition to signals on the uplink control channels and the uplink data channels. The SRS is transmitted from the mobile station 100, 100a in response to a command from the base station 200. The following describes how to multiplex the SRS and other uplink signals.

FIG. 8 illustrates an example of uplink signals including ACKs according to the first embodiment. FIG. 8 describes how to allocate radio resources when a signal presenting ACK and SRS is multiplexed in a Short CP subframe. The Short CP subframe includes 14 characters. Seven characters of the first half make up the slot, and also seven characters of the second half make up the slot.

In each of the slots of the first and second half of the uplink control channel i, four of these seven symbols are allocated for the ACK, while the other three are allocated for the RS (pilot). More specifically, characters are allocated for ACK, ACK, RS, RS, RS, ACK and ACK in order from the first character. It should be noted that one bit is sufficient for the ACK / NACK signal, and thus the same signal is transmitted in the characters allocated for the ACK.

Similarly, for the uplink control channel i in each of the slots of the first and second halves of the uplink control channel j, four of these seven symbols are allocated for the ACK, while the other three are allocated for the RS. However, when one or more mobile stations transmit SRS, the first symbol of each slot is used to transmit SRS and is not used to transmit ACK.

The broadband radio resource that is allocated for the SRS does not include the frequency range of the uplink control channel i, but includes the frequency range of the uplink control channel j. Thus, it is preferable that the frequency range of the uplink control channel i and that of the SRS is not sequential. This is because an increase in the number of mobile stations belonging to the base station 200 may increase the need to provide a wider frequency range for the uplink control channel i.

In a radio resource allocated for SRS, SRS signals from multiple mobile stations can be encoded, multiplexed, and then transmitted. Thus, the mobile stations 100 and 100a can transmit their SRS signals simultaneously. It should be noted that the mobile station 100, 100a does not output a signal at all frequencies of the radio resource allocated to the SRS, but selects parts of the frequencies and outputs a signal. For this reason, based on the transmission quality of the selected frequency parts, the transmission quality of other frequencies can be estimated.

Consider the case where the mobile stations 100 and 100a exist in the same cell, one mobile station 100 transmits an SRS, and the other mobile station 100a does not transmit.

In this case, the base station 200 distributes to the mobile station 100, which is supposed to transmit the SRS, the radio resource to be used for transmitting the SRS, and the uplink control channel j as the uplink control channel. According to this allocation, the mobile station 100 transmits the SRS in the first symbol of each slot.

In order to transmit an ACK in addition to the SRS in the same subframe, the mobile station 100 uses the uplink control channel j in symbols other than the first symbol of each slot. However , if the mobile station 100 has an uplink data channel designated by the base station 200, the mobile station 100 transmits the ACK on the uplink data channel, not on the uplink control channel j. In this case, the mobile station 100 also avoids using the first symbol in each slot.

On the other hand, the base station 200 distributes the uplink control channel i as an uplink control channel for the mobile station 100a, which is not supposed to transmit SRS. The mobile station 100a uses the uplink control channel i to transmit the ACK. At this time, the mobile station 100a can use all the slots in the subframe. However, if the mobile station 100a has an uplink data channel assigned by the base station 200, the mobile station 100a transmits the ACK on the uplink data channel, not on the uplink control channel i. In this case, the mobile station 100 avoids using the first symbol in each slot. The base station 200 provides advance notice to the mobile station 100a that the mobile station 100 is supposed to transmit SRS.

If no mobile station transmits SRS in the cell, the base station 200 allocates the uplink control channel i of the mobile station moving at low speed and the control channel j uplink of the mobile station moving at high speed. For this reason, such a mobile station moving at a low speed can transmit SRS at longer intervals since the quality of communication with the mobile station may not be often measured.

FIG. 9 illustrates an example of uplink signals including CQIs according to the first embodiment. FIG. 9 describes how to allocate radio resources when a signal indicative of CQI and SRS is multiplexed in a Short CP subframe.

In each of the slots of the first and second half of the uplink control channel i, five of these seven symbols are allocated for CQI, while the other two are allocated for RS. More specifically, characters are allocated for CQI, CQI, RS, CQI, RS, CQI and CQI in order from the first character. It should be noted that the CQI signal is divided and transmitted in a variety of characters.

Similarly, for the uplink control channel i, in each of the slots of the first and second half of the uplink control channel j, five of these seven symbols are allocated for CQI, while the other two are allocated for RS. However, when one or more mobile stations transmit SRS, the first symbol is used for SRS transmission and is not used for CQI transmission.

As described above in the ACK case of FIG. 8, the uplink control channel j is allocated to the mobile station, which is supposed to transmit SRS, and the uplink control channel i is allocated to the mobile station, which is not supposed to transmit SRS . Therefore, even when another mobile station transmits SRS, a mobile station that does not transmit SRS can use all the symbols in a subframe to transmit CQI over the uplink control channel.

10 illustrates another example of uplink signals including ACKs according to the first embodiment. Figure 10 describes how to allocate radio resources in the case when a signal indicating ACK and SRS is multiplexed in a subframe with Long CP. The Long CP subframe includes twelve characters. Six characters of the first half make up the slot, and six characters of the second half make up the slot.

In each of the slots of the first and second half of the uplink control channel i, four of these six symbols are allocated for the ACK, while the other two are allocated for the RS. More specifically, characters are allocated for ACK, ACK, RS, RS, ACK and ACK in order from the first character. All characters allocated to the ACK transmit the same signal.

Similarly, for the uplink control channel i, in each of the slots of the first and second halves of the uplink control channel j, four of these six symbols are allocated for ACK, while the other two are allocated for RS. However, when one or more mobile stations transmit SRS, the first symbol is used for SRS transmission and is not used for ACK transmission.

As described above in the case of Short CP in FIG. 8, the uplink control channel j is allocated to the mobile station, which is supposed to transmit SRS, and the uplink control channel i is allocated to the mobile station, which is not supposed to transmit Srs. Therefore, even when another mobile station transmits SRS, a mobile station that does not transmit SRS can use all the symbols in a subframe to transmit ACK over the uplink control channel.

11 illustrates another example of uplink signals including CQIs according to the first embodiment. 11 describes how to allocate resources in the case where a signal indicating CQE and SRS is multiplexed in a subframe with Long CP.

In each of the slots of the first and second half of the uplink control channel i, five of these six symbols are allocated for CQI, while another symbol is allocated for RS. More specifically, characters are allocated for CQI, CQI, RS, CQI, CQI and CQI in order from the first character. It should be noted that the CQI signal is divided and transmitted in a variety of characters.

Similarly, for the uplink control channel i, in each of the slots of the first and second half of the uplink control channel j, five of these six symbols are allocated for CQI, while another symbol is allocated for RS. However, when one or more mobile stations transmit SRS, the first symbol is used for SRS transmission and is not used for CQI transmission.

As described above in the case of the Short CP in FIG. 9, the uplink control channel j is allocated to the mobile station, which is supposed to transmit SRS, and the uplink control channel i is allocated to the mobile station, which is not supposed to transmit Srs. Therefore, even when another mobile station transmits SRS, a mobile station that does not transmit SRS can use all the symbols in a subframe to transmit CQI over the uplink control channel.

8-11 describe how an ACK or CQI is transmitted as an example of an uplink signal. Other types of control information may be transmitted in the same manner. In addition, not only one type of control information, but also some types of control information can be transmitted in the same subframe. For example, ACKs and CQIs may be transmitted in the same subframe.

The following describes how to control the distribution of radio resources between the mobile stations 100 and 100a and the base station 200. The following examples are cases of multiplexing an SRS and a signal over an uplink data channel and multiplexing an SRS and a signal over an uplink control channel.

12 is a sequence diagram illustrating distribution control in a case where SRS and uplink data are overlapped. The sequence in FIG. 12 will be described in stages. This explanation focuses on the uplink from the mobile station 100 to the base station 200.

(Step S11) The base station 200 detects the need to measure uplink communication quality from the mobile station 100 to the base station 200. Then, the base station 200 allocates the radio resource to be used for transmitting the SRS to the mobile station 100 and sets transmission intervals. Then, the base station 200 transmits the distribution information on the control channel downlink.

(Step S12) The mobile station 100 transmits the SRS with the radio resource allocated in step S11. Base station 200 measures uplink communication quality based on an SRS received from mobile station 100.

(Step S13) After that, the mobile station 100 transmits the SRS in the transmission intervals set in step S11, and accordingly, the base station 200 measures the communication quality based on the received SRS.

(Step S14) The mobile station 100 detects a request to send packet data to the base station 200. Then, the mobile station 100 sends a request for the distribution of radio resources over the uplink control channel.

(Step S15) The base station 200 distributes the uplink data channel of the mobile station 100 in response to the distribution request received in step S14. At this time, the base station 200 selects a frequency range to be used based on the measurement results adopted in steps S12 and S13. Then, the base station 200 transmits UL allocation grant information on the downlink control channel.

(Step S16) The mobile station 100 transmits packet data on the uplink data channel allocated in step S15.

(Step S17) The base station 200 redistributes the uplink data channel of the mobile station 100 after receiving packet data from the mobile station 100, then transmits UL allocation grant information on the downlink control channel. After that, the transmission of packet data from the mobile station 100 and the distribution of the uplink data channel by the base station 200 are repeated until the packet data transmission is completed.

(Step 318) The base station 200 detects an overlapping (overlapping) SRS transmission and packet data from the mobile station 100 when the data channel is allocated on the uplink, that is, it detects that the SRS and the packet data must be transmitted in the same subframe. Then, the base station 200 sends an overlay report with SRS transmission along with UL allocation grant information on the downlink control channel.

(Step S19 ) The mobile station 100 transmits the SRS with the radio resource allocated in step S11. Base station 200 measures uplink communication quality based on an SRS received from mobile station 100.

(Step S20) The mobile station 100 transmits packet data on the uplink data channel allocated in step S18 in characters other than those used for transmitting the SRS.

As described above, the mobile station 100 periodically transmits the SRS in response to a command from the base station 200, and accordingly, the base station 200 measures the uplink communication quality based on the received SRS. Then, after receiving a request for allocation of an uplink data channel, the base station 200 selects a frequency band to be allocated based on the results of the measurement of communication quality.

When the SRS and the signal on the uplink data channel are to be multiplexed, the mobile station 100 transmits packet data so that the uplink data channel for transmitting packet data does not overlap with the radio resource for transmitting SRS.

13 is a sequence diagram illustrating distribution control in a case where SRS and ACK overlap. The sequence in FIG. 13 will be described in stages.

The following explanation focuses on the uplink from the mobile station 100 to the base station 200.

(Step S21) The base station 200 detects the need to measure uplink communication quality from the mobile station 100 to the base station 200. Then, the base station 200 allocates the radio resource to be used for transmitting the SRS to the mobile station 100, sets transmission intervals, and then transmits information distribution on the control channel downlink.

(Step S22) The mobile station 100 transmits the SRS with the radio resource allocated in step S21, and the base station 200 measures the uplink communication quality based on the SRS received from the mobile station 100.

(Step S23) After that, the mobile station 100 transmits the SRS in the transmission intervals set in step S21, and accordingly, the base station 200 measures the communication quality based on the received SRS.

(Step S24) The base station 200 receives packet data addressed to the mobile station 100. Then, the base station 200 sends a report of the radio resource used for the downlink data channel on the downlink control channel, and also transmits the packet data on the downlink data channel communication lines.

(Step S25) In response to the packet data received in step S24, the mobile station 100 transmits an ACK or NACK on the uplink control channel. More specifically, the mobile station 100 transmits an ACK if the demodulation and decoding of packet data is successfully completed. Conversely, the mobile station 100 transmits a NACK if demodulation and decoding are not successful.

(Step S26) The base station 200 sends a report of the radio resource used for the downlink data channel over the downlink control channel, and also transmits packet data over the downlink data channel. The packet data to be transmitted here is the packet data to be transmitted after the ACK is received in step S25. If NACK is received, then the packet data transmitted last time is transmitted again. Thereafter, the transmission of the ACK / NACK response from the mobile station 100 and the transmission of packet data from the base station 200 are repeated until the transmission of packet data is completed.

(Step S27) When the downlink data channel is allocated, the base station 200 detects an overlapping SRS and ACK / NACK transmission from the mobile station 100, that is, detects that the SRS and ACK / NACK must be transmitted in the same subframe. Then, the base station 200 allocates various uplink control channels to the mobile station 100 and other mobile stations, which are not supposed to transmit SRS. The distribution of the uplink data channels is changed by changing the distribution of the downlink control channels. Then, the base station 200 sends a report of the radio resource used for the downlink data channel over the downlink control channel and also transmits packet data over the downlink data channel.

(Step S28) The mobile station 100 transmits the SRS with the radio resource allocated in step S21, and the base station 200 measures the uplink communication quality based on the SRS received from the mobile station 100.

(Step S29) In response to the packet data in step S27, the mobile station 100 transmits an ACK or NACK on the uplink control channel in characters other than those used for transmitting the SRS.

As described above, in response to a command from the base station 200, the mobile station 100 periodically transmits the SRS, and accordingly, the base station 200 measures the uplink communication quality based on the received SRS. Upon receipt of packet data addressed to the mobile station 100, the base station 200 transmits the packet data on the downlink data channel. After receiving the packet data, the mobile station 100 transmits an ACK / NACK response.

If the SRS and the ACK / NACK signal are to be multiplexed, then the base station 200 allocates various uplink control channels to the mobile station 100 and other mobile stations, which are not supposed to transmit SRS. Mobile station 130 transmits ACK / NACK so that the uplink control channel for ACK / NACK transmission does not overlap with the radio source for SRS transmission.

The above description describes a case where the same mobile station transmits packet data, or control information, and SRS. The same control may apply when different mobile stations transmit them.

In the above communication system, one of the two uplink control channels can be used without interference with respect to the SRS, even in a subframe including SRS transmission. Therefore, the SRS and the control information signal can be multiplexed so as not to cause deterioration in communication quality. In addition, by using both the SRS that is received in the slot of the first half and the SRS that is received in the slot of the second half, the base station can measure the quality of a wide frequency range.

(Second Embodiment)

A second embodiment is described below in detail with reference to the accompanying drawings. This section focuses on differences from the above first embodiment and omits an explanation of the same features. The communication system according to the second embodiment uses one subframe, and not one slot, as a transmission interval for a pair of two SRS signals.

The communication system according to the second embodiment may be implemented in the same configuration as in the first embodiment. The mobile station and the base station according to the second embodiment can be implemented with the same module configurations as the mobile station 100 and the base station 200 in FIGS. 3 and 4, as in the first embodiment, respectively. However, the second embodiment transmits and receives the SRS and measures communication quality at a different time from the first embodiment. The following description of the second embodiment uses the same reference numbers of the mobile station and the base station as the first embodiment.

Fig. 14 illustrates an example of uplink signals including ACKs according to a second embodiment. Fig. 14 illustrates how to allocate radio resources when a signal indicating ACK and SRS is multiplexed in two consecutive Short CP subframes.

In each slot of the uplink control channel i, four of the seven symbols are allocated for the ACK, while the other three symbols are allocated for the RS. More specifically, characters are allocated for ACK, ACK, RS, RS, RS, ACK and ACK in order from the first character. However, when one or more mobile stations transmit SRS, the first symbol of the second subframe is used for SRS transmission and is not used for ACK transmission.

Similarly, for the uplink control channel i in each slot of the uplink control channel j, four of the seven symbols are allocated for the ACK, while the other three are allocated for the RS. However, when one or more mobile stations transmit SRS, the first symbol of the first subframe is used for SRS transmission and is not used for ACK transmission.

In the first symbol of the first subframe, the broadband radio resource that is allocated for the SRS does not include the frequency range of the uplink control channel i, but includes the resource of the uplink control channel j. In the first symbol of the second subframe, the broadband radio resource that is allocated for the SRS includes the frequency range of the uplink control channel i, but does not include the resource of the uplink control channel j.

The mobile station, which is supposed to transmit SRS, is allocated the uplink control channel j of the first subframe and the uplink control channel i of the second subframe. On the other hand, the mobile station, which is not supposed to transmit SRS, is allocated the uplink control channel i of the first subframe and the uplink control channel j of the second subframe. Therefore, a mobile station that does not transmit SRS but transmits ACK over the uplink control channel can use all the characters in the subframes, even when the other mobile station transmits SRS. In addition, base station 200 can measure communication quality based on SRS signals received in the first symbols of two consecutive subframes.

15 illustrates an example of uplink signals including CQIs according to a second embodiment. FIG. 15 illustrates an example of how to allocate radio resources when a signal indicating CQI and SRS is multiplexed in two consecutive Short CP subframes.

In each slot of the uplink control channel i, five of the seven symbols are allocated for CQI, while the other two are allocated for RS. More specifically, characters are allocated for CQI , CQI, RS, CQI, RS, CQI and CQI in order from the first character. However, when one or more mobile stations transmit SRS, the first symbol of the second subframe is used for SRS transmission and is not used for CQI transmission.

Similarly, for the uplink control channel i, in each slot of the uplink control channel j, five of these seven symbols are allocated for CQI, while the other two are allocated for RS. However, when one or more mobile stations transmit SRS, the first symbol of the first subframe is used for SRS transmission and is not used for CQI transmission.

As described for the ACK example in FIG. 14, a mobile station that is supposed to transmit SRS is allocated an uplink control channel j of a first subframe and an uplink control channel i of a second subframe. On the other hand, the mobile station, which is not supposed to transmit SRS, is allocated the uplink control channel i of the first subframe and the uplink control channel j of the second subframe. Therefore, a mobile station that does not transmit SRS but transmits CQI on the uplink control channel can use all the symbols in subframes, even when the other mobile station transmits SRS. Then, the base station 200 can measure the quality of communication based on the SRS signals received in the first symbols of two consecutive subframes.

14 and 15 illustrate how ACK or CQI is transmitted as an example of an uplink signal. The same technique can be applied to transfer other types of control information. In addition, not only one type of control information, but also various types of control information can be transmitted in the same subframe. For example, ACKs and CQIs may be transmitted in the same subframe. In addition, FIGS. 14 and 15 illustrate an example of Short CP. However, Long CP may be used as described in the first embodiment.

Such a communication system may provide the same results as those of the first embodiment. In addition, the communication system according to the second embodiment can suppress a decrease in the number of signals that need to be time-multiplexed with the SRS over the uplink control channel.

(Third Embodiment)

A third embodiment is described in detail below with reference to the accompanying drawings. This section focuses on differences from the above first embodiment and omits an explanation of the same features. The communication system according to the third embodiment allows the mobile station to transmit diversity antennas, that is, to perform radio communication with multiple antennas.

The communication system according to the third embodiment may be implemented in the same system configuration as in the first embodiment according to FIG. 2, except that the mobile station and the base station in the third embodiment perform antenna diversity. The mobile station and the base station in the third embodiment are given reference numerals 100b and 200a, respectively.

FIG. 16 is a block diagram illustrating functions of a mobile station according to a third embodiment. The mobile station 100b includes transmitting and receiving antennas 110 and 110b, a data processor 120, a pilot processor 330, a control information processor 140, a resource selection unit 150b, a transmitter 160b, a receiver 170b, and a downlink quality measurement unit 180. The data processor 120, the pilot signal processor 130, the control information processor 140, and the downlink quality measurement unit 180 have the same functions of the respective components as in the first embodiment of FIG. 3.

Transmit and receive antennas 110 and 110b are antennas for transmission and reception. Each transmitting and receiving antenna 110, 110b transmits uplink signals output from the transmitter 160b by radio to the base station 200a. In addition, the transmitting and receiving antenna 110, 110b receives downlink signals transmitted by radio communication from the base station 200a and transmit signals to the receiver 170b. During transmission, the transmitter 160b selects one of the transmit and receive antennas 110 and 110b.

The resource selection unit 150b controls uplink radio resources that are available to the mobile station 100b. In addition, a resource selection unit 150b controls switching between transmitting and receiving antennas 110 and 110b for use in radio transmission. The resource selection unit 150b provides the transmitter 160b with information regarding the current state of the allocation of radio resources and the choice of which antenna to use.

The transmitter 160b identifies radio resources that should be used to transmit pilot data, pilot, and control information based on information provided by the resource selection unit 150b. The transmitter 160b also selects a transmitting and receiving antenna to be used for each transmission based on information provided by the resource selection unit 150b. Then, the transmitter 160b modulates and multiplexes the signals, outputs the result to the selected transmit and receive antenna.

When receiving signals with transmitting and receiving antennas 110 and 110b, the receiver 170b selects a signal with high reception quality and then demodulates and decodes the signal addressed to its own station from the selected received signal. Packet data included in the received signal, if any, is enclosed internally.

The receiver 170b transmits UL allocation grant information of the resource selection unit 150b included in the received signal, if any. If the control information to instruct the antenna switching is included in the received signal, then the receiver 170b transmits the information to the resource selection unit 150b. In addition, the receiver 170b provides a downlink quality measurement unit 180 to a signal that should be used to measure downlink communication quality with respect to the received signal.

The control method for switching the antenna of the resource selection unit 150b includes open loop control and closed loop control. In open-loop control, the resource selection unit 150b switches between transmitting and receiving antennas 110 and 110b as planned. For example, the resource selection unit 150b periodically switches between transmitting and receiving antennas 110 and 110b.

In closed loop control, on the other hand, the resource selection unit 150b switches between transmitting and receiving antennas 110 and 110b in response to a command from the base station 200a. The base station 200a instructs which antenna to use based on, for example, the transmission quality of the signals received from the respective transmitting and receiving antennas 110 and 110b.

The control method to be adopted is set in advance in the resource selection unit 150b. This embodiment uses closed-loop control.

The base station 200a according to the third embodiment may be implemented in the same module configuration as in the base station 200 of the first embodiment of FIG. 4, except that communication quality is measured by each of the transmitting and receiving antennas 110 and 110b provided in the mobile station 100b.

FIG. 17 illustrates an example of uplink signals including ACKs according to a third embodiment. FIG. 17 illustrates how to allocate radio resources when a signal indicating ACK and SRS is multiplexed in a Short CP subframe. The upper signals are signals that are transmitted from the transmitting and receiving antennas 110 to the base station 200a, while the lower signals are signals that are transmitted from the transmitting and receiving antennas 110b to the base station 200a. It should be noted that FIG. 17 does not illustrate signals that are transmitted from other mobile stations.

As in the aforementioned first embodiment, the mobile station 100b, which is supposed to transmit SRS, is allocated uplink control channel j. Now suppose that the mobile station 100b selects a transmitting and receiving antenna 110 for radio transmission. Then, the mobile station 110b transmits the ACK and RS signals on the uplink control channel j from the transmitting and receiving antennas 110. The mobile station 110b also transmits an SRS at the beginning of each slot.

Thus, one of the two SRS signals is transmitted from the transmitting and receiving antennas 110, and the other signal is transmitted from the transmitting and receiving antennas 110b. Thus, the mobile station 100b is designed to transmit SRS from the transmitting and receiving antennas 110b even during transmission of the ACK from the transmitting and receiving antennas 110. This allows the base station 200a to measure the communication quality of both the transmitting and receiving antennas 100 and 100b.

FIG . 18 illustrates an example of uplink signals including CQIs according to a third embodiment. FIG. 18 illustrates how to allocate radio resources when a signal indicating CQI and SRS is multiplexed in a Short CP subframe.

The mobile station 100b transmits the CQI and RS signals on the uplink control channel j from the transmitting and receiving antennas 110. The mobile station 100b also transmits an SRS at the beginning of each slot. Thus, one of the two SRS signals is transmitted from the transmitting and receiving antennas 110, while the other signal is transmitted from the transmitting and receiving antennas 110b. Thus, the mobile station 100b is designed to transmit SRS from the transmitting and receiving antennas 110b even during CQI transmission from the transmitting and receiving antennas 110. This allows the base station 200a to measure the communication quality of both the transmitting and receiving antennas 110 and 110b.

Meanwhile, only for the mobile station 100b, in order to select the antenna to be used, there is no need to measure the transmission quality of a wide frequency range. Additionally, if the mobile station 100b does not have packet data for uplink transmission within a predetermined period of time, the base station 200a does not need to measure the quality of transmission frequencies that can be used for the uplink data channel. Therefore, while there is no packet data to be transmitted on the uplink, the mobile station 100b misses the SRS transmission at frequencies different from the frequency range of the uplink control channel.

FIG. 19 illustrates another example of uplink signals including ACKs according to a third embodiment. FIG. 19 illustrates how to allocate radio resources when a signal indicating ACK and SRS is multiplexed in a sub-frame with a Short CP and the mobile station 100b does not have packet data for transmission.

The mobile station 100b transmits ACK and RS signals on the uplink control channel j from the transmitting and receiving antennas 110. The mobile station 100b also transmits SRS with only the frequency range of the uplink control channel j at the beginning of each slot. Thus, SRS transmission is performed from the transmitting and receiving antennas 110 in one of these two slots and from the transmitting and receiving antennas 110b in the other slot.

This prevents the base station 200a from receiving information that should be used to select the frequency range to be allocated to the uplink data channel, but allows the base station 200a to receive information that should be used by the mobile station 100b to select the antenna to be to be used. In order to skip an SRS transmission using frequencies other than the frequency range of the uplink control channel, the mobile station 100b provides advance notice to the base station 200a that the mobile station 100b does not have packet data for transmission.

FIG. 20 illustrates another example of uplink signals including CQIs according to a third embodiment. FIG. 20 illustrates how to allocate radio resources when a signal indicative of CQI and SRS is multiplexed in a Short CP subframe and the mobile station 100b does not have packet data for transmission.

The mobile station 100b transmits CQI and RS signals on the uplink control channel j from the transmitting and receiving antennas 110. The mobile station 100b also transmits SRS with only the frequency range of the uplink control channel j at the beginning of each slot. Thus, SRS transmission is made from the transmitting and receiving antenna 110 in one of these two slots and from the transmitting and receiving antenna 110b in the other slot.

This prevents the base station 200a from receiving information that should be used to select the frequency band to be allocated to the uplink data channel, but allows the base station 200a to receive information that should be used by the mobile station 100b to select an antenna, which should be used.

17-20 illustrate how an ACK or CQI is transmitted as an example of an uplink signal and how other types of control information can be transmitted in the same way. In addition, not only one type of control information, but also some types of control information can be transmitted in the same subframe. For example, ACK and CQI may be transmitted in the same subframe. In addition, although FIGS. 17-20 illustrate an example of Short CP, Long CP can be used as described in the first embodiment. Additionally, the SRS may be transmitted in the first characters of two consecutive subframes, as described in the second embodiment.

Such a communication system may provide the same results as the results of the first embodiment. Additionally, with the communication system according to the third embodiment, the results of measuring the communication quality based on the SRS signals can be used to select the antenna for antenna diversity. Additionally, when the mobile station does not have packet data for transmission, the frequency range can be reduced for SRS transmission, thereby reducing the burden of measuring the quality of communication to the base station.

Although this embodiment uses the first symbol of each slot to transmit SRS, a predetermined symbol, except the first, can be used to transmit SRS. Further, although this embodiment transmits a pair of SRS signals in two consecutive slots or subframes, SRS signals can be transmitted in separate slots or subframes. Additionally, this embodiment uses two limit (boundary) frequencies of the frequency range available between the mobile station and the base station for two uplink control channels, a predetermined frequency range other than the limit frequencies can be used.

The preceding description is considered as only an illustration of the principles of the present invention. Additionally, since numerous modifications and changes will be apparent to those skilled in the art, it is not desirable to limit the invention to the precise design and uses shown and described, and accordingly, all suitable modifications and equivalents may be deemed to fall within the scope of the invention in the appended claims inventions and their equivalents.

Description of Reference Positions

one Transmission device 1a Transmitter 2 Receiving device 2a Quality Measurement Unit

Claims (14)

1. A transmission device that is capable of performing both data transmission in the first frequency range and data transmission in the second frequency range, the transmission device comprising:
a transmitter that transmits a signal to be used by the receiving device to measure communication quality in a third frequency range in a predetermined part of a first time period, and transmits a signal in a fourth frequency range in a predetermined part of a second time period occurring after a first time period, wherein the third frequency range includes a second frequency range and does not include a first frequency range, the fourth frequency range includes a first frequency range and does not include a second range he frequencies, and the first frequency range is used to transmit data in a given part of the first time period, and the second frequency range is used to transmit data in a given part of the second time period. 2. The transmission device according to claim 1, in which when performing both signal transmission and data transmission in the first time period and the second time period, the transmitter performs data transmission in the second frequency range in the first time period with the exception of the aforementioned predetermined part used for transmission signal, and performs data transmission in the first frequency range in the second time period with the exception of the aforementioned predetermined portion used to transmit the signal. 3. The transmission device according to claim 1, in which:
each of the first time period and the second time period includes a first sub-period of time including a predetermined portion used for transmitting a signal, and a second sub-period of time not including a predetermined portion for transmission of a signal; and
when performing both signal transmission and data transmission in the first time period, the transmitter transmits data in the second frequency range in the first time sub-period of the first time period except for a predetermined part used for signal transmission, and performs data transmission in the first frequency range in the second sub-period time of the first time period, and when performing both signal transmission and data transmission in the second time period, the transmitter transmits data in the first frequency range in the first sub At the time of the second time period, with the exception of the predetermined part used for signal transmission, it performs data transmission in the second frequency range in the second time sub-period of the second time period. 4. The transmission device according to claim 1, further comprising a plurality of antennas, wherein the transmitter uses various antennas to transmit the signal in the first time period and in the second time period. 5. The transmission device according to claim 4, in which the transmitter does not transmit a signal in a frequency range other than the first and second frequency ranges, when there is no transmission other than said data transmission in the first frequency range and data transmission in the second frequency range. 6. The transmission device according to claim 1, in which the transmitter transmits a signal at the beginning of the first time period and at the beginning of the second time period. 7. The transmission device according to claim 1, in which one of the maximum frequency and minimum frequency of the frequency range used to transmit a frame that includes data and a signal is included in the first frequency range, and the other frequency is included in the second frequency range. 8. A reception device for communicating with a transmission device that is capable of performing both data transmission in the first frequency range and data transmission in the second frequency range, the receiving device comprising:
a quality measuring unit that measures the quality of communication with the transmission device based on a signal that is transmitted from the transmission device in the third frequency band in a given part of the first time period, and a signal that is transmitted from the transmission device in the fourth frequency band in a given part of the second time period, coming after the first period of time, and the third frequency range includes a second frequency range and does not include a first frequency range, while the fourth frequency range includes the first frequency range and does not include the second frequency range,
moreover, the first frequency range is used to transmit data in a given part of the first time period, and the second frequency range is used to transmit data in a given part of the second time period. 9. The receiving device of claim 8, further comprising a radio resource manager that allocates a first frequency range in a first time period and a second frequency range in a second time period to another transmission device that is not intended to transmit a signal in a first time period and a second time period . 10. The receiving device according to claim 8, in which:
each of the first time period and the second time period includes a first sub-period of time including a predetermined portion used to transmit a signal, and a second sub-period of time not including a predetermined portion; and
the receiving device further comprises a radio resource manager that allocates a first frequency range in a first time sub-period and a second frequency range in a second time sub-period of a first time period for transmitting data of another transmission device that is not intended to transmit a signal in a first time period, and allocates a second frequency range in a first time sub-period and a first frequency range in a second time sub-period of a second time period for transmitting data of another transmission device, to It is not intended for signal transmission in a second time period. 11. The receiving device of claim 8, in which, when the signal is transmitted using various antennas in the first time period and the second time period, the quality measuring unit measures the communication quality for each of the various antennas. 12. The receiving device according to claim 11, in which the quality measuring unit measures the quality of communication based on a signal of only the first and second frequency ranges, when the transmission device does not perform any transmission other than data transmission in the first frequency range and data transmission in the second frequency range. 13. The receiving device of claim 8, in which the quality measuring unit measures the quality of communication based on the signal transmitted at the beginning of the first time period and at the beginning of the second time period. 14. The receiving device of claim 8, in which one of the maximum frequency and minimum frequency of the frequency range used to transmit the frame, which includes data and a signal, is included in the first frequency range, and the other frequency is included in the second frequency range.

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