KR101002247B1 - A method and an apparatus for transmitting/receiving data and control information on uplink in wireless telecommunication system - Google Patents

Abstract

The present invention relates to a method and apparatus for multiplexing and transmitting uplink control information with data in order to support downlink data transmission in a wireless communication system and receiving the control information and data. In a system of multiplexing the uplink packet data channel and the control channel, the transmission format of the control channel for transmitting control information is changed according to the transmission format of the data channel. The present invention can increase the efficiency of the data channel resources by adjusting the amount of resources for the control channel when transmitting high-speed data.

SC-FDMA, CQI, ACK / NACK information, control channel transmission, packet data channel, multiplexing

Description

Method and apparatus for transmitting and receiving data and control information through uplink in a wireless communication system {A METHOD AND AN APPARATUS FOR TRANSMITTING / RECEIVING DATA AND CONTROL INFORMATION ON UPLINK IN WIRELESS TELECOMMUNICATION SYSTEM}

1 shows a transmitter structure of a typical LFDMA system.

2 illustrates the transmission of control information in a typical SC-FDMA system.

3 is a diagram illustrating a structure of a transmitter for multiplexing control information and packet data before DFT in a typical SC-FDMA system and transmitting the same;

4 is a diagram illustrating a transmission procedure of a terminal for a first preferred embodiment of the present invention.

5 is a diagram illustrating a reception procedure of a base station for the first preferred embodiment of the present invention.

6 is a block diagram showing an apparatus for transmitting a terminal for a first preferred embodiment of the present invention.

7 is a block diagram showing a receiving device of a base station for the first preferred embodiment of the present invention.

8 is a diagram illustrating a transmission procedure of a terminal for a second preferred embodiment of the present invention.

9 is a diagram illustrating a reception procedure of a base station for a second preferred embodiment of the present invention.

10 is a block diagram showing an apparatus for transmitting a terminal for a third preferred embodiment of the present invention.

Fig. 11 is a block diagram showing a receiving device of a base station for the third preferred embodiment of the present invention.

12 is a flowchart illustrating a procedure in which a terminal transmits data and control information together for a fourth preferred embodiment of the present invention.

13 is a flowchart illustrating a procedure of simultaneously receiving data and control information by a base station according to a fourth preferred embodiment of the present invention.

14 is a block diagram showing an apparatus for transmitting a terminal according to a fourth embodiment of the present invention.

15 is a block diagram showing a receiving device of a base station according to a fourth preferred embodiment of the present invention.

 The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for transmitting a data channel and a control channel in the same transmission time period.

As an example of a wireless communication system, a transmission scheme in a Single Carrier Frequency Division Multiple Access (SC-FDMA) system is largely divided into a Distributed FDMA (DFDMA) system and a Localized FDMA (LFDMA) system. .

Figure 1 shows the transmitter structure of a typical LFDMA system. Discrete Fourier Transform (DFT) Precoder 101 and Inverse Fast Fourier Transform (IFFT) In addition to the configuration using 102, other transmitters may be implemented. The implementation using the DFT precoder 101 and the IFFT 102 as shown in FIG. 1 has the advantage of facilitating changes in LFDMA system parameters with low hardware complexity.

Referring to FIG. 1, the difference between OFDM and SC-FDMA is described in terms of a transmitter structure. In addition to the IFFT 102 used for multi-carrier transmission in a conventional OFDM transmitter, in the LFDMA transmitter, the DFT precoder 101 uses the IFFT ( Additionally at the front end of 102). The transmission modulation symbols 103 are input to the DFT precoder 101 in units of blocks. M subcarrier components constituting the signal output from the DFT precoder 101 are mapped to input points NM to N-1 of the IFFT 102 to occupy a band of adjacent subcarriers. Will be sent. In general, the input / output size N of the IFFT 102 has a larger value than the input / output size M of the DFT pre-encoder 101. The output signal of IFFT 102 is transmitted via parallel / serial converter 104 and CP adder 106.

The control information to be transmitted by the terminal through the control channel in the reverse transmission is mainly ACK (Acknowledge) / NACK (non-Acknowledge) or Channel Quality Indication (CQI) required for the transmission of the downlink packet data.

2 shows the transmission of control information in a typical SC-FDMA system.

Referring to FIG. 2A, in order to transmit control information, the SC-FDMA system allocates a frequency resource 201 separate from the data channel to the control channel. In case of transmitting control information through the allocated frequency resource 201, it is impossible for the terminal to transmit packet data. This is because when the packet data and the control information are simultaneously transmitted in the same transmission interval, the peak to average power ratio (PAPR) may be increased because the single carrier characteristics are not satisfied. Therefore, when the terminal needs to transmit control information in the transmission period for transmitting the packet data, as shown in FIG. 2 (b), the control information is transmitted together with the data using the frequency resource 203 of the data channel. In other words, the packet data, the control information, and the reference signal are multiplexed and transmitted in time within the same frequency resource 203.

3 illustrates a structure for multiplexing and transmitting packet data and control information before inputting a DFT precoder in a typical SC-FDMA system. As shown, the data 301 composed of P symbols and the control information 302 composed of S symbols are each multiplexed into M symbols through the multiplexer 303, and then a DFT precoder having a size M ( 304). The output of the DFT precoder 304 is mapped to the input of an IFFT 305 of size N as described above.

When packet data and control information are multiplexed prior to the DFT precoder, as shown in FIG. 3, scheduled M input symbols need to be allocated according to the information amount of each of the data channel and the control channel. One of the general schemes is to allocate input symbols according to a set transmission format of each of a control channel and a data channel, such as wideband code division multiple access (WCDMA). In other words, when the number of symbols according to the fixed transmission format of the control channel is set, the remaining input symbols except for the number of symbols of the control channel are used for data transmission. This is because the rate of the data channel is usually variable according to scheduling and the transmission format of the control channel is fixedly set by higher signaling.

However, when the transmission format of the control channel is fixed as described above, the number of symbols that can be transmitted to the packet data channel is reduced by the number of symbols occupied by the control channel, thereby reducing the data transmission rate. In this case, the data transmission rate is reduced by [the number of symbols used for the control channel x MCS (Modulation and Coding Scheme) level]. The problem is that the size of the data bits that cannot be increased.

Accordingly, the present invention provides a method and apparatus for adjusting the amount of resources used in the control channel according to the data rate of the terminal in a wireless communication system.

The present invention provides a method and apparatus for adjusting the amount of resources of a control channel according to a transmission format to be used based on a transmission rate scheduled by a terminal or a transmission rate that a terminal intends to use for data transmission.

The present invention provides a method and apparatus for transmitting control information using the same modulation scheme that the terminal intends to use for data transmission.

The present invention provides a method and apparatus for calculating the number of modulation symbols required for transmission of a control channel according to the transmission format of a data channel.

The present invention provides an apparatus and method for transmitting a terminal for multiplexing and transmitting a data channel and a control channel in an SC-FDMA system.

The present invention provides an apparatus and method for receiving a base station for receiving multiplexed data channels and control channels in an SC-FDMA system.
A method for transmitting data and control information in a wireless communication system according to the present invention comprises the steps of determining a control channel format given by a transmission format used for a data channel, and generating data according to the transmission format of the data channel. And generating control information according to the determined control channel format, and multiplexing the data and the control information and transmitting the multiplexed data through the subcarrier resources allocated for the data channel.
In addition, an apparatus for transmitting data and control information in a wireless communication system according to the present invention includes a controller for determining a control channel format given by a transmission format used for a data channel, and generating data according to the transmission format of the data channel. A data generator, a control information generator for generating control information according to the determined control channel format, and a transmitter for multiplexing the data and the control information and transmitting them through a subcarrier resource allocated for the data channel.
In addition, the method for receiving data and control information in a wireless communication system according to the present invention comprises the steps of: receiving an uplink signal including data and control information through a subcarrier resource allocated for the data channel; Determining the control channel format given by the transmission format used for the control; and demultiplexing the uplink signal according to the transmission format and the control channel format of the data channel to obtain the data and the control information. Include.
In addition, the apparatus for receiving data and control information in a wireless communication system according to the present invention includes a receiver configured to receive an uplink signal including data and control information through a subcarrier resource allocated for the data channel, and the data channel. A controller configured to determine a control channel format given by a transmission format used for the decompression; and a demultiplexing configured to demultiplex the uplink signal into the data and the control information according to the transmission format of the data channel and the control channel format. Include groups.

Hereinafter, embodiments of the present invention will be described in detail with the accompanying drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

An important aspect of the present invention is to change the amount of resources used by the control channel according to the data rate in order to efficiently use transmission resources when data and control information are simultaneously transmitted over an uplink in a wireless communication system. . In this case, the time interval is referred to as, for example, a transmission time interval (TTI).

In general, the transmission rate refers to the amount of information data transmitted by the terminal for a unit time. However, the transmission rate may mean an amount of radio resources required by the terminal to transmit the information data. In other words, the transmission rate in the present invention should be understood to mean the transmission power level or the size of the transmission bits transmitted by the terminal during the unit time, that is, the transmission time unit. The size of the transmission bits means the number of physical layer bits in the physical layer, the number of modulation symbols, or the size of a transport block indicated by a transmission format. The transmit power level refers to power transmitted by the terminal, which may mean absolute transmit power, but is a power level required to actually transmit data after compensating for a path loss difference or a channel difference between terminals. It may also mean an additional power level (i.e., power offset) required to transmit the corresponding data amount, which is equivalent to the signal to noise ratio (SNR) required for the base station to receive the data amount normally. .

To this end, the present invention is basically a method of selecting a transport format (TF) of a control channel (hereinafter referred to as a control channel format) according to a data rate and the same control information and data having a variable transport format (TF). The present invention proposes a transmission / reception apparatus for transmitting / receiving during a time interval. In addition, a method of defining or calculating another control channel format according to the data transmission rate and a method of transmitting data to resources other than the resources of the selected control channel are also proposed.

The main feature of the present invention is to determine the control channel format such as the number of symbols, the number of bits, or the modulation scheme of the control channel required for transmitting the control information. When used together with data, the control channel format is determined based on the transmission rate or transmission format of the data channel for every TTI. Here, each symbol means a modulated complex symbol and is mapped to one transmission unit, for example, one subcarrier or subband.

In the following description, a transmission rate or transmission format of a data channel for determining a transmission format of a control channel, an MCS level indicating a modulation scheme (MS) and a coding rate of a data channel, and a transmission format indicating an amount of data that can be transmitted Embodiments in the case of using the (TF) index and the power level required for the data channel will be described. However, even if not specifically mentioned herein, any kind of information that can know the transmission rate or transmission format of the data channel can be used to determine the transmission format of the control channel according to the present invention. In the judgment of those skilled in the art will be possible. In addition, in the following description, specific examples of the reverse link of the wireless communication system using the SC-FDMA scheme will be used in describing the operation and configuration of the present invention. However, the specific system configuration does not limit the scope of the present invention.

<< first embodiment >>

The terminal presets a plurality of control channel formats according to the MCS level indicating the modulation scheme and the code rate of the data, and selects and controls the control channel format based on the MCS level of the data channel transmitted every transmission time interval (TTI). Set the channel. Here, the MCS level represents a combination of a modulation scheme (for example, Quadrature Phase Shift Keying (QPSK), 16-ary Quadrature Amplitude Modulation (16QAM)) and a coding rate used for data transmission. The higher this, the higher the data rate. That is, when control information is multiplexed with data transmission, encoding of control information is given by the modulation scheme and code rate used for uplink data channel transmission.
For convenience, in the first embodiment, the format of the control channel is defined as the number of symbols for the control channel obtained after modulation. In another embodiment, at least one of parameters such as an MCS level, a physical layer bit number, a code rate, and the like may be defined as a transmission format of a control channel.

Since the allowable power level per modulation symbol is also small when data is transmitted at a low MCS level, many modulation symbols are used for the transmission of control information to obtain an energy level that satisfies the reception quality. When data is transmitted at a high MCS level, a high power level per modulation symbol can be allocated because the channel condition of the UE is good, and thus an energy level that satisfies the required reception quality even when using fewer modulation symbols for transmission of control information. Can be obtained.

Table 1 below shows various examples of setting the control channel format. When only control information is transmitted without data, when the number of symbols (original symbols) for control information is called S_ori, the data exists. The number of symbols S for control information is shown. In another embodiment, S_ori is a signaled value or a value predetermined by the designer.

Data channel
MCS Level Control channel
Number of symbols (S)
(Example 1) Control channel
Number of symbols (S)
(Example 2) Number of symbols in the control channel (S)
(Example 3) QPSK, 1/3 10 S_ori S_ori * PSD_control / PSD_1 QPSK, 1/2 10 S_ori S_ori * PSD_control / PSD_2 QPSK, 2/3 10 S_ori S_ori * PSD_control / PSD_3 QPSK, 3/4 10 S_ori S_ori * PSD_control / PSD_4 QPSK, 4/5 10 S_ori S_ori * PSD_control / PSD_5 16QAM, 1/3 6 S_add S_ori * PSD_control / PSD_6 16QAM, 1/2 6 S_add S_ori * PSD_control / PSD_7 16QAM, 2/3 6 S_add S_ori * PSD_control / PSD_8 16QAM, 3/4 6 S_add S_ori * PSD_control / PSD_9 16QAM, 4/5 6 S_add S_ori * PSD_control / PSD_10

In Example 2 of the number of symbols for the control channel, when only control information is transmitted alone (without data), when data is transmitted at a low MCS level, the data and control information use the same format, and the data uses a high MCS level. In this case, the format (S_add) additionally set for the control information is followed. Here, S_sdd has a smaller value than S_ori.

In example 3 of the control channel symbol number, when data transmission power is used to transmit the control channel and the data channel simultaneously, the number of symbols required for the control channel is required to satisfy the total energy. Therefore, compared to transmitting only the control channel, if the data transmission power is set higher, use fewer symbols (S), otherwise use more symbols (S). The symbol number S_ori of the control channel is determined by scaling the symbol number S_ori. Here, PSD_control (Power Spectrum Density-control) indicates a power level required for transmitting only a control channel, and PSD_n indicates a power level required for transmission in an nth data channel transmission format. The format information indicating the number of symbols of the control channel as follows may be predefined as a standard or may be set through higher signaling.

4 is a flowchart illustrating a procedure in which a terminal transmits data and control information together for the first preferred embodiment of the present invention.

Referring to FIG. 4, when the control information and data to be transmitted in the same TTI are generated in step 401, the UE checks the MCS level for the data channel as in step 402 and controls by the MCS level. Select the channel format. In step 403, the control information consisting of the S symbols is generated by adjusting the code rate or the number of repetitions of the control information to match the number of symbols S of the control channel format. When the code rate is fixed, the terminal performs rate matching on the input control information similarly to data to generate control information consisting of S control symbols according to the number of symbols S to be actually transmitted.

In step 404, the terminal calculates the number P of symbols for the data channel. In this case, the number of symbols P for the data channel is the number of symbols corresponding to the total scheduled resources, minus the number of control channel symbols. (P = MS) Next, in step 405, the number of symbols P is determined. Accordingly, data consisting of P symbols is generated. In more detail, the terminal generates data consisting of P data symbols by performing rate matching and modulation on all information bits to be transmitted to match the number of data channel symbols P, which is the amount of physical layers that can be transmitted. The generated data and the control information are multiplexed and transmitted in step 406.
In this case, the execution order of the data generation steps 404 and 405 and the control information generation step 403 is not limited to those shown, but may be performed in parallel or reverse order.

5 is a flowchart illustrating a procedure of simultaneously receiving data and control information by a base station according to the first embodiment of the present invention.

Referring to FIG. 5, in operation 501, a signal multiplexed with control information and data is received through a predetermined frequency resource. Since the CQI is periodically transmitted by the terminal and the ACK / NACK information is transmitted only when downlink data is received, the base station knows a time period for receiving the signal including data and control information. In step 502, the base station selects a control channel format. Specifically, the base station selects a control channel format corresponding to the MCS level determined through scheduling for the terminal. The base station notifies the terminal in advance of the MCS level of the data channel determined through scheduling as scheduling information, and the terminal transmits data using the same MCS level as the MCS level scheduled by the base station, so that the control channel format used in the base station and the terminal Is always the same.

In step 503, the base station obtains the symbol number P of the data channel using the symbol number of the selected control channel format. In operation 504, the demultiplexing operation is performed on the received signal using the number of symbols of the data channel and the control channel, thereby converting the received signal including M symbols into symbols of P data channels and S control channels. Separate symbols from. In step 505 and 506, the base station performs demodulation and decoding on the symbols of each channel to output pure data and control information. In this case, the steps 505 and 506 are not limited to those shown, and may be performed in parallel or reverse order.

6 is a block diagram showing an apparatus for transmitting a terminal according to the first embodiment of the present invention.

Referring to FIG. 6, the data rate controller 601 receives MCS information scheduled by a base station from a base station through a separate channel (for example, a scheduling channel) and transmits it to the control channel controller 604. If the control information to be transmitted exists, the control channel controller 604 determines the number of symbols S of the control information corresponding to the MCS level of the data channel indicated by the MCS information, for example, according to the aforementioned <Table 1>. Decide The control information generator 603 receives the symbol number S of the control information from the control channel controller 604 and includes S controls including control information through encoding, rate matching, and modulation on input information bits. Create symbols.

When the control channel controller 604 transmits the symbol number S of the control information to the data rate controller 601, the data rate controller 601 is used for data transmission based on the symbol number S of the control information. Calculate the number of possible symbols P. The data generator 602 generates P data symbols including data through encoding, rate matching, and modulation on input information bits according to the symbol number P of the data transmitted from the data rate controller 601. do.

The generated data symbols and the control symbols are multiplexed by the multiplexer 605, and the DFT precoding unit 605 converts the M symbols output from the multiplexer 605 into SC-FDMA symbols. To generate a frequency domain signal. The IFFT unit 607 maps the frequency domain signal to the assigned subcarriers, converts the frequency domain signal into a time domain signal, and transmits the converted time domain signal.

7 is a block diagram showing a receiving apparatus of a base station according to the first embodiment of the present invention.

Referring to FIG. 7, the base station processes a signal received during one TTI through an FFT unit 707 and an IDFT unit 706 to obtain a signal of a specific terminal composed of M symbols. The demultiplexer 705 separates the signal of the terminal into data and control information, wherein the number of symbols occupied by each channel is notified from the scheduler 701.
That is, the scheduler 701 determines the MCS level of the data channel and transmits MCS information indicating the MCS level to the control channel controller 704. If control information to be transmitted exists, the control channel controller 704 determines the number of symbols S used for the control channel of the terminal based on the MCS level indicated by the MCS information, and the number of symbols S of the control channel. ) Is sent to the scheduler 701. The scheduler 701 determines that the number of symbols P of the data channel P, except for S, is the number of symbols used for data transmission. After transmission, the demultiplexer 705 notifies the number of symbols P and S of each channel.

The data demodulator 702 is informed of the number of symbols P of the data channel from the scheduler 701 and demodulates the symbols of the data channel separated by the demultiplexer 705 according to the modulation scheme and the code rate of the corresponding MCS level. And decode. To this end, the scheduler 701 provides the data demodulator 702 with information about the number of symbols and detailed operations of the data channel. The control information demodulator 703 is informed of the number of symbols S of the control channel from the control channel controller 704 and demodulates the symbols of the control channel separated through the demultiplexer 705 according to the corresponding modulation scheme and code rate. And decode to obtain control information such as ACK / NACK or CQI.

<< 2nd Example >>

According to the second embodiment, the terminal modulates and transmits the control channel in the same modulation scheme as the data channel for efficient resource usage. In the related art, since it is difficult to frequently change the control channel format according to the channel condition of the terminal, the terminal has used a fixed low format for the control channel in order to maintain reliability. Since the data channel is instantaneously scheduled according to the channel state information of the terminal, it is possible for the base station to variably set a high or low transmission rate for the data channel according to the channel state of the terminal. When the base station allocates a high data rate to the data channel, it may be determined that the channel condition of the terminal is good or the transmission power is sufficient. Therefore, the control channel can also be transmitted using high power. Thus, in the second embodiment, the control information is modulated by the same modulation method as that of the data, and accordingly, the number of symbols for the control information is adjusted.

For the preferred implementation of the second embodiment, the modulation scheme of the control channel is defined under the same manner as the modulation scheme of each data channel as shown in Table 2 below. The number of symbols required for the control channel is then determined according to the modulation scheme.

Data channel modulation scheme Control channel modulation method QPSK QPSK 16QAM 16QAM

8 is a flowchart illustrating a procedure in which a terminal transmits data and control information together according to a second embodiment of the present invention.

Referring to FIG. 8, when control information and data to be transmitted in the same TTI are generated in step 801, the terminal proceeds to step 802 to identify a modulation scheme indicated by the MCS level of the data channel. In the following, an operation in which two of QPSK and 16QAM are used as the modulation scheme of the data channel will be described. However, the present invention can be applied to other modulation schemes.

If the modulation scheme of the data channel is QPSK, the controller proceeds to step 803 and the terminal modulates the control information to QPSK and selects the symbol number Sqpsk determined for the case of QPSK. On the other hand, if the modulation scheme of the data channel is 16QAM, the process proceeds to step 804 and the UE modulates the control information to 16QAM and selects the number S of symbols corresponding to 16QAM as the number of symbols S _qam . The number of bits of control information before channel coding is known, and in general, 16QAM can transmit twice as many bits as QPSK. Therefore, when 16QAM is used, the number of symbols (S _qam ) required for transmission of control information is QPSK. It is cut in half compared to the case (S _qpsk ).

In step 805, the UE calculates the number of symbols P available for the data channel to generate the data channel. The number of symbols P of the data channel corresponds to a value other than the number of control channel symbols S in the total allocated frequency resources M. (P = MS) If the number of symbols P for data transmission is found, In step 806, the terminal generates data through a rate matching process. In step 807, the terminal multiplexes the data as control information and transmits the data. In this case, the execution order of the data generation steps 805 and 806 and the control information generation step 803 or 804 is not limited to those shown, and may be performed in parallel or reverse order.

9 is a flowchart illustrating a procedure of simultaneously receiving data and control information by a base station according to a preferred embodiment of the present invention.

9, in step 901, a base station receives a signal multiplexed with control information and data through a predetermined frequency resource. In step 902, the base station determines the number of symbols of the control channel based on the modulation format of the data channel scheduled for the terminal. If the scheduled modulation format is QPSK, the number of symbols S of the control channel is selected as the number of symbols for QPSK (S _qpsk ) in step 903. If the scheduled modulation format is 16QAM, the number of symbols S of the control channel is determined in step 904. It is selected as the number of symbols for 16QAM (S _qam).

In step 905, the base station calculates the symbol number P of the data channel based on the symbol number S of the control channel. In step 906, the base station calculates M symbols according to the number of symbols of the data channel and the control channel. Demultiplexing the received signal consisting of P into symbols of P data channels and S control channels. In step 907, the base station performs demodulation and decoding on the symbols of each channel to output pure data and control information.

The second embodiment is implemented using the transmitting / receiving device of the first embodiment shown in Figs.

<< third embodiment >>

Similarly to the second embodiment, the third embodiment transmits control information in the same modulation scheme as that of data modulation, and adjusts the number of symbols for transmitting the control information. Perform multiplexing of data and control information at the bit level. When the multiplexing is performed before the modulation, the UE or the base station need not separately select the modulation scheme of the control channel according to the modulation scheme of the data channel, so that the transmission / reception procedure of the third embodiment is performed by the second implementation shown in FIGS. 8 and 9. Same as the transmission and reception procedure of the example.

10 is a block diagram showing an apparatus for transmitting a terminal according to a third embodiment of the present invention.

Referring to FIG. 10, when the data rate controller 1001 wants to transmit data and control information together, the data resource for transmitting the data is variable, so that the data rate controller 1001 transmits the control information through the control channel controller 1004. You are informed of the amount of resources. Unlike the second embodiment, since data and control information are multiplexed before modulation, the amount of resources occupied by each channel is calculated by the number of bits. The data rate controller 1001 receives the number of bits S _b of control information from the control channel controller 1004, and calculates P _b, which is the number of bits available for data transmission, according to the total number of bits that can be transmitted. The generator 1002 generates P _b data bits in accordance with the number of bits P _b for the data channel by encoding pure data to be transmitted and provides them as inputs of the multiplexer 1005.

To generate control information generator 1003. The by encoding the pure control information to be transmitted S _b of the control information bits according to the bit number S _b of the control information calculated by the control channel controller 1004, a multiplexer 1005 Provide as input. The multiplexer 1005 receives the bits of the data and control information and performs multiplexing. The multiplexed bits are modulated by the same modulation scheme through the modulator 1006 and then transmitted through the DFT precoder 1007 and the IFFT unit 1008.

11 is a block diagram showing a receiving apparatus of a base station according to a third embodiment of the present invention.

Referring to FIG. 11, the base station processes a signal received during one TTI from the terminal through the FFT unit 1108 and the IDFT unit 1107 to obtain a signal of a specific terminal composed of M symbols. The symbols are demodulated by a demodulator 1106 in a demodulation scheme corresponding to the same modulation scheme and then input to the demultiplexer 1105 in the form of a bit stream.
The scheduler 1101 determines the MCS level of the data channel and transmits MCS information indicating the MCS level to the control channel controller 1104. If the control information to be transmitted exists, the control channel controller 1104 determines the number of symbols S _b used for the control channel of the terminal based on the MCS level indicated by the MCS information, and determines the number of symbols of the control channel ( S _b ) is transmitted to the control information demodulator 1103 and the scheduler 1101. The scheduler 1101 determines that P _b excluding S _b is the number of bits used for data transmission from the total number of bits that the terminal can transmit, and demultiplexer 1105 and data of the bit number P _b of the data channel. Transfer to a demodulator 1102.
The demultiplexer 1105 receives the number of bits P _b and S _b of each channel from the scheduler 1101 and the control channel controller 1104, and separates the bits of each channel from the bit stream to demodulate the data demodulator 1102. And control information demodulator 1103, respectively. Demodulators 1102 and 1103 demodulate and decode the input bits under the control of scheduler 1101 and control information controller 1104 to obtain pure data and control information.

<< fourth embodiment >>

The terminal presets a plurality of control channel formats according to a data transmission format (TF), and selects a control channel format corresponding to the TF of data to be transmitted at every transmission time period to set the control channel. Fourth Embodiment TF refers to a transport block size (TBS), which is an amount of data to be transmitted by a UE, and is determined by the total amount of available frequency resources and the MCS level. For convenience of description, the fourth embodiment defines the control channel format as the number of symbols for the control channel. Although not described in detail, in a modified embodiment, parameters such as the MCS level and the number of physical layer bits may be defined as a control channel transmission format.

Since low permissible power levels are typically small per symbol when low TF is used, many symbols are used for the transmission of control information to obtain an energy level that satisfies the reception quality. When data is transmitted at a high MCS level, a high power level per symbol can be allocated because the channel condition of the UE is good, so that an energy level that satisfies the required reception quality can be obtained even using fewer symbols for transmission of control information. Can be.

Table 3 below shows various examples of setting the control channel format.

Data channel
TF index (k) Control channel
Number of symbols (S)
(Example 1) Number of symbols in the control channel (S)
(Example 2) One S1 S_ref * PSD_ref / PSD_1 2 S2 S_ref * PSD_ref / PSD_2 3 S3 S_ref * PSD_ref / PSD_3 4 S4 S_ref * PSD_ref / PSD_4 5 S4 S_ref * PSD_ref / PSD_5 6 S5 S_ref * PSD_ref / PSD_6 7 S6 S_ref * PSD_ref / PSD_7 8 S7 S_ref * PSD_ref / PSD_8 9 S8 S_ref * PSD_ref / PSD_9 10 S9 S_ref * PSD_ref / PSD_10

Example 1 shows the case in which the number of symbols of the control channel is defined for each TF, and example 2 shows the power level required to predefine the number of reference symbols (S_ref) and to transmit data for each TF (where k is the TF). The case where the number of symbols S required for the control channel is calculated by comparing PSD_ref, which is the power level of the data when the index) and the reference symbol number are used. In the following Table 3, when the power level of the data is high, the power level available for the control channel is also high, so that it is possible to transmit control information using fewer symbols.

12 is a flowchart illustrating a procedure of transmitting data and control information together by a terminal for the fourth preferred embodiment of the present invention.

12, when control information and data to be transmitted in the same TTI are generated in step 1201, the UE checks the TF index for the data channel as in step 1202 and selects the control channel format given by the TF index. do. In step 1203, the UE generates control information consisting of S symbols by adjusting the code rate or the number of repetitions of the control information to match the number of symbols S of the control channel format. When the code rate is fixed, the terminal performs rate matching on the input control information similarly to data to generate control information consisting of S control symbols according to the number of symbols S to be actually transmitted.

In step 1204, the UE calculates the number P of symbols for the data channel. Here, the number of symbols P for the data channel is the remaining number of symbols except for the control channel symbols from the number M of symbols according to the total amount of scheduled resources. (P = MS) In step 1205, P according to the number of symbols P Data consisting of two symbols is generated. In more detail, the terminal generates data consisting of P data symbols by performing rate matching and modulation on all information bits to be transmitted to match the number of data channel symbols P, which is the amount of physical layers that can be transmitted. The generated data and the control information are multiplexed and transmitted in step 1206.

13 is a flowchart illustrating a procedure of simultaneously receiving data and control information by a base station according to a fourth embodiment of the present invention.

Referring to FIG. 13, in step 1301, a base station receives a signal multiplexed with control information and data through a predetermined frequency resource. Since the CQI is periodically transmitted by the terminal and ACK / NACK information is transmitted only when downlink data is received, the base station knows a transmission time period for receiving the signal including data and control information. In step 1302, the base station selects a control channel format. Specifically, the base station selects a control channel format corresponding to the TF index determined through scheduling for the terminal. The base station notifies the terminal in advance of the MCS level of the data channel determined through scheduling as scheduling information, and the terminal transmits data using the same TF index as the TF index scheduled by the base station, so that the control channel format used in the base station and the terminal Is always the same.

In step 1303, the base station obtains the symbol number P of the data channel by using the symbol number of the selected control channel format. In operation 1304, the demultiplexing operation is performed on the received signal using the number of symbols of the data channel and the control channel, so that the received signal including M symbols is converted into symbols of P data channels and S control channels. Separate symbols from. In step 1305 and 1306, the base station performs demodulation and decoding on the symbols of each channel to output pure data and control information.

14 is a block diagram showing an apparatus for transmitting a terminal according to a fourth embodiment of the present invention.

Referring to FIG. 14, the data rate controller 1401 receives TF information scheduled by a base station from a base station through a separate channel (for example, a scheduling channel) and transmits the received TF information to the control channel controller 1404. If the control information to be transmitted exists, the control channel controller 1404 determines the number of symbols S of the control information corresponding to the TF index of the data channel indicated by the TF information, for example, according to the aforementioned <Table 3>. Decide The control information generator 1403 receives the symbol number S of the control information from the control channel controller 1404 and generates S control symbols including control information.

When the control channel controller 1404 transmits the symbol number S of the control information to the data rate controller 1401, the data rate controller 1401 is used for data transmission based on the symbol number S of the control information. Calculate the number of possible symbols (P). The data generator 1402 generates data through rate matching and modulation on input information bits according to the number of symbols P of the data transmitted from the data rate controller 1401.
The generated data symbols and symbols of the control information are multiplexed by the multiplexer 1405, and the DFT precoder 1405 performs DFT conversion on the M symbols output from the multiplexer 1405 to SC-FDMA symbols. It generates a frequency domain signal consisting of. The IFFT unit 1407 converts the frequency domain signal into allocated subcarriers, converts the frequency domain signal into a time domain signal, and transmits the converted time domain signal.

15 is a block diagram showing a receiving apparatus of a base station according to a fourth preferred embodiment of the present invention.

Referring to FIG. 15, a base station processes a signal received during one TTI through an FFT unit 1507 and an IDFT unit 1506 to obtain a signal of a specific terminal composed of M symbols. The demultiplexer 1505 separates the signal of the terminal into data and control information, wherein the number of symbols occupied by each channel is notified from the scheduler 1501. That is, the scheduler 1501 determines the MCS level of the data channel and notifies the control channel controller 1504 of the TF index according to the MCS level. If the control information to be transmitted exists, the control channel controller 1504 determines the number of symbols S used for the control channel of the terminal based on the TF index scheduled to the terminal, and the number of symbols S of the control channel. ) Is sent to the scheduler 1501. The scheduler 1501 determines that the symbol number P of the data channel P is the number of symbols used for data transmission, except that S is the number of symbols M corresponding to all resources allocated to the terminal, and the data demodulator 1502 determines the number of symbols P of the data channel. After transmission, the demultiplexer 1505 notifies the number of symbols P and S of each channel.

The data demodulator 1502 is informed of the symbol number P of the data channel from the scheduler 1501, and demodulates and decodes the symbols of the data channel separated by the demultiplexer 1505 according to the corresponding TF index. To this end, the scheduler 1501 provides the data demodulator 1502 with information about the number of symbols and detailed operations of the data channel. The control information demodulator 1503 is informed of the number of symbols S of the control channel from the control channel controller 704 and demodulates the symbols of the control channel separated through the demultiplexer 1505 according to the corresponding modulation scheme and code rate. And decode to obtain control information such as ACK / NACK or CQI.

<< Fifth Embodiment >>

Although the fifth embodiment is similar to the fourth embodiment, the control channel format is determined according to the power level required for data transmission without determining the control channel format for each TF. In addition, the power level required in this embodiment means the absolute transmit power of the terminal, or means a power offset additionally set to the reference power level in consideration of each TF and service compared to the reference power level. The reference transmit power refers to a power level adjusted by power control of the base station when power control is performed so that the base station maintains a constant reception level. The additional set power compared to the reference power level is equivalent to the received SNR required for receiving the corresponding data at the base station. In general, in the case of data transmission of the same service, the larger the TF index of the data channel, that is, the higher the transmission rate, the higher the power level required for data transmission. In this case, the power level required for data transmission may mean symbol power per subcarrier in the frequency domain or power level per modulation symbol in the time domain. For convenience of description, in the fifth embodiment, the control channel format is defined as the number of symbols for the control channel. In a modified embodiment, parameters such as the MCS level and the number of physical layer bits may be defined as a control channel transmission format.

Table 4 below shows various examples of setting the control channel format.

Data channel
PSD Control channel
Number of symbols (S)
(Example 1) Number of symbols in the control channel (S)
(Example 2) PSD1 S1 S_ref * PSD_ref / PSD_1 PSD2 S2 S_ref * PSD_ref / PSD_2 PSD3 S3 S_ref * PSD_ref / PSD_3 PSD4 S4 S_ref * PSD_ref / PSD_4 PSD5 S4 S_ref * PSD_ref / PSD_5 PSD6 S5 S_ref * PSD_ref / PSD_6 PSD7 S6 S_ref * PSD_ref / PSD_7 PSD8 S7 S_ref * PSD_ref / PSD_8 PSD9 S8 S_ref * PSD_ref / PSD_9 PSD10 S9 S_ref * PSD_ref / PSD_10

Example 1 illustrates a case where a symbol number of a control channel is defined for each PSD representing a power level of a data channel. When the power level of the control channel is larger or smaller than the power level of the data, inefficiency occurs in using the transmission power of the terminal. When the data channel and the control channel are transmitted simultaneously, the power level of the control channel is the same as the data channel. It is preferable to set. In this case, in order to maintain the reliability of the control channel, as the power level of the data channel is lower, the number of symbols of the control channel may be increased, and thus the control information symbols may be repeated more. Alternatively, when the power level of the data channel is high, the number of control information transmitted may be reduced to minimize the puncturing loss occurring in the data part for transmitting the control information. Table 4 shows how to set the control channel format to calculate the number of symbols required to stably receive the control information when the power level of the control information is set to the same level as the data channel.

Example 2 predefines the number of reference symbols (S_ref), PSD_k (where k is the PSD index of the data channel) and the power level of the data channel when using the reference symbol number, the power level required to transmit data for each PSD This is a case of calculating the number of symbols required for the control channel by comparing the PSD_ref. In the following Table 4, when the power level of the data channel is high, the power level available for the control channel also increases, so that it is possible to transmit control information using a small amount of symbols. When the power level of the data channel is low, a larger amount of symbols can be transmitted, so that the reliability of the control channel can be maintained even with a low PSD.

The procedure and apparatus of the terminal and the base station of the fifth embodiment are the same as those of the fourth embodiment, except that the PSD of the data channel is a criterion for selecting a control channel transmission format instead of the TF information.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but is capable of various modifications within the scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention that operates as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

The present invention multiplexes control information and data for uplink transmission in a wireless communication system using a single carrier frequency division multiple access scheme, thereby achieving an effect of reducing PAPR by satisfying a single carrier characteristic.

Claims (60)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete In the method for transmitting data and control information in a wireless communication system, Generating the control information; When the control information to be transmitted and the information data are generated in the same transmission period, determining the number of symbols for transmission of the control information in consideration of the amount of the information data to be transmitted; Multiplexing the information data and the control information; And Transmitting the multiplexed information data and control information. 26. The method of claim 25, And the control information is ACK / NACK or CQI. 26. The method of claim 25, The number of symbols for transmission of the control information is determined by considering the amount of resources scheduled along with the amount of information data to be transmitted. 26. The method of claim 25, The multiplexed information data and control information is transmitted through the resources scheduled for the information data. The method of claim 28, And the information data is transmitted using the remaining resources except for the control information. 26. The method of claim 25, When only the control information is transmitted in the interval during the same transmission, And the control information is transmitted through resources preset for the control. 26. The method of claim 25, And the control information is multiplexed with the information data before modulation. 26. The method of claim 25, And in order to demodulate the control information and the information data based on a time division multiplexing scheme, the control information is multiplexed with a reference signal to be transmitted. 26. The method of claim 25, And when the control information and the information data are transmitted together in the same transmission period, the control information and the information data are modulated by the same modulation scheme. A terminal device for transmitting data and control information in a wireless communication system, A control information generator for generating the control information; A control channel controller for determining the number of symbols for transmission of the control information in consideration of the amount of the information data to be transmitted, when the control information to be transmitted and the information data occur in the same transmission period; A multiplexer for multiplexing the information data and the control information; And And a transmitter for transmitting the multiplexed information data and control information. The method of claim 34, The control information terminal device characterized in that the ACK / NACK or CQI. The method of claim 34, The control channel controller determines the number of symbols for transmission of the control information in consideration of the amount of resources scheduled along with the amount of information data to be transmitted. The method of claim 34, And the transmitting unit transmits the multiplexed information data and control information through resources scheduled for the information data. The method of claim 37, And the information data is transmitted using the remaining resources except for the control information. The method of claim 34, When only the control information is transmitted in the interval during the same transmission, And the control information is transmitted through resources preset for the terminal. The method of claim 34, And the multiplexer multiplexes the control information and the information data before modulation. The method of claim 34, And the demodulator multiplexes the control information and a reference signal to be transmitted in order to demodulate the control information and the information data based on a time division multiplexing scheme. The method of claim 34, And a terminal for modulating the control information and the information data by the same modulation scheme when the control information and the information data are transmitted together in the same transmission period. A method of receiving data and control information in a wireless communication system, Receiving an uplink signal including control information and information data generated in a section during the same transmission from a user terminal; Determining the number of symbols for transmission of the control information in consideration of the amount of transmitted information data; And And demultiplexing the uplink signal according to the number of symbols for transmission of the control information to obtain the information data and the control information. The method of claim 43, And the control information is ACK / NACK or CQI. The method of claim 43, The number of symbols for transmission of the control information is determined in consideration of the amount of the scheduled resources together with the amount of the transmitted information data, characterized in that the method for receiving data and control information. The method of claim 43, And the uplink signal is transmitted from the user terminal through resources scheduled for the information data. The method of claim 46, And the information data is transmitted from the user terminal using the remaining resources except for the control information. The method of claim 43, When only the control information is transmitted in the interval during the same transmission from the user terminal, And the control information is transmitted from the user terminal through resources preset for the user. The method of claim 43, The uplink signal is demultiplexed into the information data and the control information after demodulation. The method of claim 43, And demodulating the control information and the information data based on a time division multiplexing scheme, wherein the control information is multiplexed with a reference signal to be transmitted from the user terminal. The method of claim 43, And the uplink signal is demodulated by the same demodulation method when the control information and the information data are transmitted in the same transmission interval from the user terminal. A base station apparatus for receiving data and control information in a wireless communication system, A receiving unit for receiving an uplink signal including control information and information data generated in a section during the same transmission from a user terminal; A controller which determines the number of symbols for transmission of the control information in consideration of the amount of transmitted information data; And And a demultiplexer for demultiplexing the uplink signal according to the number of symbols for transmission of the control information to obtain the information data and the control information. The method of claim 52, wherein The control information base station apparatus characterized in that the ACK / NACK or CQI. The method of claim 52, wherein The controller determines the number of symbols for the transmission of the control information in consideration of the amount of the scheduled resources together with the amount of the transmitted information data. The method of claim 52, wherein And the uplink signal is transmitted from the user terminal through resources scheduled for the information data. The method of claim 55, And the information data is transmitted from the user terminal using the remaining resources except for the control information. The method of claim 52, wherein When only the control information is transmitted in the interval during the same transmission from the user terminal, The control information base station device, characterized in that transmitted through the resources set for them. The method of claim 52, wherein And the demultiplexer demultiplexes the uplink signal into the information data and the control information after demodulation. The method of claim 52, wherein And the control information is multiplexed with a reference signal to be transmitted from the user terminal in order to demodulate the control information and the information data based on a time division multiplexing scheme. The method of claim 52, wherein And the uplink signal is demodulated by the same demodulation scheme when the control information and the information data are transmitted in the same transmission interval from the user terminal.

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