KR101371809B1 - Method for channel quality information change and data transmission of high speed downlink packet access and communication system thereof - Google Patents

Abstract

The present invention relates to a method for changing channel state information and data transmission in a fast downlink packet access and a communication system applied thereto. The present invention provides a method of receiving channel state information before a change, selecting a transmission mode of any one of transmission modes of a mobile terminal device, and changing the channel state information by a one-to-one mapped value with the selected transmission mode. Receiving the changed channel state information from the portable terminal device; changing the transmission amount, transmission rate, and number of allocated channels based on the changed channel state information based on the channel state information; Is transmitted to the portable terminal device. According to the present invention as described above it is possible to change the data transmission method between the base station (Node B) and the terminal device has the advantage of reducing the power consumption of the mobile terminal device.

Fast downlink packet access, channel state information (CQI), base station (Node B), power consumption.

Description

CHANNEL FOR CHANNEL QUALITY INFORMATION CHANGE AND DATA TRANSMISSION OF HIGH SPEED DOWNLINK PACKET ACCESS AND COMMUNICATION SYSTEM THEREOF}

1 is a configuration of a communication system for explaining a preferred embodiment of the present invention.

2 is a detailed configuration diagram of the mobile terminal and the base station (Node B) shown in FIG.

3 is a table of channel state information provided to explain an embodiment of the present invention.

4 is a flowchart illustrating a channel state change and data transmission method using fast downlink packet access according to an exemplary embodiment of the present invention.

Description of the Related Art [0002]

10: portable terminal device 12: communication module

16: mode selector 17: memory

18: control unit 30: base station (Node B)

35 analysis unit 36 determination unit

The present invention relates to a system of a high speed packet access method, and more particularly, to a mobile terminal apparatus in accordance with a change in channel quality information (CQI), which is transmitted from a portable terminal apparatus to a base station Node B. The present invention relates to a method for changing channel state information and data transmission using a fast downlink packet connection and a communication system applied thereto.

Recently, a High Speed Downlink Packet Access (HSDPA) standard has been developed to provide a data rate of up to 10Mbps for high speed packet data service in a wireless mobile environment. The HSDPA service is a transport channel called a high speed downlink shared channel (HS-DSCH) for high speed downlink packet data service in the same frequency band (5 MHz) as in the existing Release 99 and Release 4, and a high speed shared control channel for supporting the same. By defining control channels such as HS-SCCH and HS-DPCCH, high speed packet data transmission can be performed without affecting the existing system.

The fast downlink packet access method determines the CQI in a user equipment (UE), and the CQI is a bit rate and encoding of data transmitted from the base station Node B to the UE. Coding) is important information for determining the method. Once the CQI is determined in the terminal device, the base station Node B changes the bit rate and the encoding scheme according to the CQI so that data is transmitted to the terminal device without breaking the data at an optimum rate.

However, at present, when obtaining the CQI from the terminal device, only factors such as interference factors between cells, thermal noise, and transmission delay time are considered. That is, the terminal apparatus generates power consumption differently according to a transmission mode when performing a high speed packet access method with a base station Node B. The transmission speed according to the amount of power consumption is not considered at all. If the transmission mode according to the power consumption is considered, the battery power of the terminal device may be used more efficiently. Therefore, it is necessary to consider the transmission speed according to the power consumption amount in the portable terminal device.

Accordingly, an object of the present invention is to provide a method for changing channel state information for changing a channel state information (CQI) value transmitted from a portable terminal device to a base station (Node B) according to a transmission mode. .

Another object of the present invention is to provide a method for transmitting data from a base station Node B to a mobile terminal using changed channel state information.

Another object of the present invention is to provide a communication system for transmitting data to a portable terminal device by applying a transmission method determined by changed channel state information.

Another object of the present invention is to provide a portable terminal apparatus which reduces overall transmission power and transmission amount according to channel state information change, thereby reducing overall power consumption.

In the method for changing the channel state information of the fast downlink packet access of the present invention for achieving the above object, the step of receiving the channel state information before the change, the step of selecting any one of the transmission mode of the portable terminal device, And changing the channel state information by a one-to-one mapped value with the selected transmission mode.

In addition, the data transmission method according to another aspect of the present invention, the step of receiving the changed channel state information from the portable terminal device, based on the channel state information, the amount of transmission, the transmission rate, the number of allocated channel state information before the change is changed And transmitting data from the base station Node B to the portable terminal device according to the changed information.

In addition, the method according to another aspect of the present invention, the channel state information (CQI) is calculated and changed by a value provided in advance according to the transmission mode of the terminal device, the changed channel state information is transmitted to the base station (Node B) The method may include: determining a transmission method based on the changed channel state information at the base station Node B, and transmitting data using the determined transmission method from the base station Node B to the terminal device. It is composed.

The transmission mode is an optimal battery mode, a maximum performance mode, a general mode.

When the changed channel state information (CQI) is lowered, the amount of data received by the terminal device is reduced.

In the maximum performance mode, a value for changing the channel state information (CQI) is set to '1', and thus, the same channel state information (CQI) value as before the change is applied.

When the changed value of the channel state information (CQI) is '0', the channel state information (CQI) is automatically changed to the channel state information '1' to enable the lowest transmission.

According to the change of the channel state information CQI, the data transmission rate, the data transmission amount, and the number of allocated channels are changed.

When the channel state information CQI is changed, only the data transmission amount is changed.

When the channel state information CQI is changed, the number of channels remains the same or is changed.

In addition, according to another aspect of the present invention, a communication system includes a portable terminal apparatus for changing a channel state information value transmitted to a base station (Node B) according to a transmission mode, and a transmission scheme determined based on the changed channel state information value. It is configured to include a base station (Node B) for transmitting data to the portable terminal device.

The portable terminal apparatus may include a mode selection unit for selecting one or more transmission modes provided to the portable terminal apparatus and a change value mapped to the transmission mode for changing channel state information (CQI) of the portable terminal apparatus. And a control unit controlling to change the channel state information CQI by a change value according to a predetermined transmission mode selected by the mode selection unit.

The transmission mode is composed of an optimal battery mode, a maximum performance mode, and a general mode.

The control unit reduces the data transmission amount, data transmission rate, and number of channels by referring to the changed channel state information value when the transmission mode is an optimal battery mode and a normal mode.

When the transmission mode is the maximum performance mode, the controller applies the same channel state information (CQI) value before the change so that data is transmitted.

The controller automatically changes the channel status information to '1' so that the lowest transmission is possible when the changed value of the channel status information CQI is '0'.

The memory is preferably a flash memory.

The base station Node B extracts the changed channel state information received from the portable terminal device and analyzes a wireless environment, and transmits data to the portable terminal device in consideration of the channel state information. Determining unit for determining the transmission rate and the encoding method for the configuration is included.

According to the present invention having such a configuration, when the transmission mode is determined according to the power consumption of the portable terminal device, the channel state information is changed by a value provided in advance, and accordingly, the base station Node B determines the transmission rate or the encoding method according to the power consumption. Determine. When the channel state information is changed, the amount of data transmitted from the base station Node B to the portable terminal device is reduced. As a result, the driving frequency of the IC which performs data processing is reduced, thereby reducing power consumption of the portable terminal device.

Hereinafter, a method of changing channel state information and data transmission of a fast downlink packet access according to a preferred embodiment of the present invention and a communication system applied thereto will be described in detail.

1 is a block diagram of a communication system for explaining an embodiment of the present invention, FIG. 2 is a detailed block diagram of a mobile terminal device and a base station Node B shown in FIG. 1, and FIG. A table of channel state information provided to explain an embodiment of the present invention is shown.

First, the communication system has evolved into a high speed / high quality wireless data packet communication system for providing a data service and a multimedia service, in addition to an initial voice-based service. The standardization of HSDPA and 1xEV-DV (Evolution in data and voice), which is currently being conducted around the 3rd Generation Partnership Project (3GPP) and 3GPP2, provides high-speed, high-quality wireless data packet transmission service of 2Mbps or higher in 3G mobile communication systems. It provides a solution.

The HSDPA communication system is expected to be able to support up to 10Mbps speed and provide shorter latency and improved capacity using downlink based on WCDMA.

A schematic diagram of such an HSDPA communication system is shown in FIG. 1.

Referring to FIG. 1, the HSDPA communication system includes one or more Radio Network Sub-Systems (RNS) 20, and each RNS 20 includes one Radio Network Controller (RNC). ) And one or more base stations (Node B) 30 managed by the RNC 22.

In addition, a mobile terminal device (hereinafter, abbreviated as 'terminal device') 10 that communicates wirelessly with the base station (Node B) 30 is configured.

2 is a detailed block diagram of a mobile terminal and a base station Node B.

The terminal apparatus 10 transmits channel state information (CQI) to the base station (Node B) 30, and the base station (Node B) 30 determines the transmission rate or the encoding method with reference to the CQI value. To transmit the data. The terminal device 10 is provided with a communication module 12, that is, HSDPA module for performing the HSDPA communication with the base station (Node B). And a storage unit 14 for storing a channel state information table provided to determine a transmission speed or an encoding method. The channel state information may be provided to a base station (Node B) 30.

The mode selection unit 16 may determine a transmission mode according to the power consumption of the terminal device 10. In this embodiment, the terminal device 10 is an example that three modes, such as the optimum battery mode, maximum performance mode, normal mode is applied. In each of the modes, a value for changing the CQI value is arbitrarily set and provided by a user. For example, the change value is equal to 'optimum battery mode: 2', 'maximum performance mode: 1', 'normal mode: 1.5'.

The HSDPA module 12 is provided with a memory 17 for storing a change value according to the mode. The memory 17 preferably uses a memory such as a flash memory so that the memory 17 can be changed.

The controller 18 is configured to calculate the CQI value of the channel state information table to the changed value stored in the memory 17. The control unit 18 transmits the change value mapped to the HSDPA module 12 in a one-to-one manner according to a transmission mode, and the components, that is, the HSDPA module 12, the storage unit 14, and the mode selector ( 16) to control the memory 17, and to control the overall operation of the terminal device (10).

Next, a base station (Node B) 30 that receives information sent from the physical layer of the terminal device 10 and transmits data to the terminal device 10 in a downlink channel is configured as described above. The base station (Node B) 30 is a terminal device through the HS-DPCCH, which is an uplink channel, in addition to functional modules such as a physical layer role unit 32, a cell management unit 33, and a wireless access unit 34 performed by a general node B. A channel state information analyzer 35 for analyzing the radio environment by extracting the changed CQI value received from 10, and a transmission rate and encoding method for transmitting data to the terminal device 10 in consideration of the CQI value It further comprises a determination unit 36 for determining the.

Meanwhile, as shown in FIG. 2, in order to provide an HSDPA service between the terminal device 10 and the base station Node B 30, a high speed dedicated physical control channel (HS) within a range that does not affect an existing communication system. -DPCCH), high speed physical downlink shared channel (HS-PDSCH), and high speed shared control channel (HS-SCCH) are additionally used.

The HS-DPCCH is used by each terminal device 10 to feed back the modulation and coding information suitable for the channel condition by selecting a base station Node B having the best downlink channel condition. In addition, the terminal 10 receiving the packet data from the base station (Node B) 30 is an uplink channel used to inform whether the packet data is received (ACK, NACK). The uplink channel includes the CQI value.

The HS-PDSCH may be used for information transmitted to the Node B 30 through the HS-DPCCH, the amount of transmission power of the Node B 30 that can be used for packet data transmission, and packet data transmission. The downlink channel is used to transmit packet data to the selected terminal device 10 in consideration of the number of channelization codes.

In addition, the HS-SCCH is a downlink channel used by the base station (Node B) 30 to transmit control information necessary for the terminal to receive packet data transmitted through the HS-DSCH and control information for other purposes.

3 is a table of channel state information provided to explain an embodiment of the present invention.

The CQI value currently contains 32 (= 2 ⁵ ) values (see FIG. 3). 3 shows CQI values from 0 to 15 and transmission status information thereof. The 5-bit information is encoded in 20 bits and transmitted. This means that the basic information amount is 5 bits, but the information amount transmitted is 20 bits. That is, the CQI encoding should be transmitted using the (20,5) encoding method, and puncturing or extending the TFCI encoding method used in the existing WCDMA according to the CQI encoding method. Several methods have been proposed.

Subsequently, a process of changing channel state information in the portable terminal device configured as described above and reducing power consumption by reducing data transmission amount will be described.

As described above, in the HSDPA service, since the terminal device 10 calculates a CQI value, which is information on a wireless environment delivered to the base station (Node B) 30, in the present invention, the CQI according to the transmission mode is focused on this point. By changing the value in the terminal device 10 and determining the transmission rate and encoding method considering the transmission mode according to the changed CQI value, a method of lowering the data transmission amount is proposed.

In general, the base station (Node B) 30 transmits packet data through the downlink channel to the terminal device 10, and then receives a signal indicating whether data transmission is successful through the uplink channel from the terminal device 10. In addition, the base station (Node B) 30 checks the success, and transmits the next data when the data is successfully transmitted.

That is, the terminal device 10 transmits CQI or ACK / NACK, which is information on whether the transmission is successful, to the base station (Node B) 30 by using an uplink channel (HS-DPCCH). Then, the base station (Node B) 30 analyzes the CQI value to determine the channel coding rate and modulation method to perform forward (ie, link from the base station to the terminal device) radio transmission. In addition, it is determined whether to transmit data according to ACK / NACK. The CQI value and the ACK / NACK information are determined according to whether there is data received from the base station (Node B) 30 through the downlink channel (HS-PDSCH) or whether a period for transmitting channel state information has been reached.

In the present embodiment, the CQI value transmitted from the terminal device 10 to the base station (Node B) 30 is changed by using a change value provided according to the transmission mode of the terminal device 10. The change value is described on the assumption that it is presented as 'optimal battery mode: 2', 'maximum performance mode: 1', 'normal mode: 1.5'.

To this end, first, in step 100, the transmission mode is determined by the mode selection unit 16 of the terminal device 10.

When the transmission mode is determined, in step 102, the controller 18 of the terminal device changes the CQI value according to the transmission mode.

The change process will be described in detail with reference to each mode and change value.

For example, when the CQI value before the change is '5', and when the transmission mode is designated as the optimum battery mode, the controller 18 changes the CQI value before the change to '2', which is a change value in the optimal battery mode. Divides by '5'. Then, in the optimal battery mode, the CQI value becomes '2' (2.5) (except the decimal point).

If the CQI value is 5 as described above, and the transmission mode is designated as the normal mode, the CQI value is '3' (3.33) by the division operation of '5 / 1.5' by the controller 18. Excluding the decimal point).

In addition, when the CQI value is 8, when the transmission mode is the optimum battery mode, the control unit 18 changes the value to '4', and in the general mode, the value is changed to '5'.

As such, the CQI value changed by the controller 18 is transmitted from the terminal device 10 to the base station Node B through the uplink channel HS-DPCCH (step 104). Then, the analysis unit 35 of the base station (Node B) 30 analyzes the transferred CQI value, and the determination unit 36 refers to the CQI value according to the analysis result, the transmission rate, the encoding method, The amount of data to be transmitted is determined (step 106).

In operation 108, data is transmitted from the base station Node B to the terminal apparatus using the determined transmission scheme.

Accordingly, referring to the CQI value lower than the CQI value before the change, referring to FIG. 3, when the CQI value is' 5, the transport block size is' 377 ', but the CQI value after the change is' 2'. As a result, the transport block size is reduced to '173'. As a result, according to the change process, a transmission rate and an encoding method suitable for transmitting data are determined, and the amount of data transmitted is reduced.

Therefore, due to the reduction in the amount of data transmitted from the base station (Node B) 30 to the terminal apparatus 10, the terminal apparatus 10 receiving the data drives the ICs for data processing (e.g., gate switching operation). ), The power consumption of the terminal device 10 can be reduced.

In addition, when the CQI value is reduced as in the number of downlink channels (Number of HS-PDSCH) of FIG. 3, the number of downlink channels transmitted from the base station (Node B) 30 to the terminal device 10 is reduced. In other words, as the CQI value increases, the channel condition is better. Accordingly, the base station (Node B) 30 allocates more radio resources to the terminal device 10 in a good channel state, but when the CQI value decreases, The number of channels associated with data transmission is reduced. This means that the power consumption of the terminal device 10 is reduced.

Therefore, if the transmission mode of the terminal device 10 is designated as the optimal battery mode, the amount of data transmission is reduced, but battery power of the terminal device 10 can be saved.

On the other hand, when the transmission mode of the terminal device 10 is designated as the maximum performance mode, it should be able to optimally transmit data transmitted from the base station (Node B) 30 to the terminal device (10). Therefore, the change value in the maximum performance mode is set to '1', and the initial CQI value determined by the terminal device 10 is used as it is. That is, since the CQI value is '5', the base station (Node B) 30 performs data transmission in the same manner as before changing the CQI value because the CQI value is used as it is.

If the changed CQI value is '0' because the changed value of the optimal battery mode and the normal mode is greater than the CQI value in step 102, the controller 18 sets the '0' value to '1' value. To change automatically. This is to prevent the CQI value '0' from being transmitted. Therefore, even if the CQI value is '0', the CQI value is '1' and thus the lowest transmission is possible.

As described above, in the present invention, since the channel state information (CQI) value can be changed in the terminal device, the base station Node B transmits data in a transmission method determined according to the transmission mode of the terminal device.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and alternative constructions without departing from the spirit and scope of the invention. It will be apparent that other, alternative and equivalent embodiments are possible. Therefore, the true scope of the present invention should be determined by the technical idea of the appended claims.

As described above, the channel state information change and data transmission method of the fast downlink packet access of the present invention and the communication system applied thereto have the following effects.

First, the portable terminal device can change the channel state information transmitted to the base station (Node B). Therefore, the base station Node B has an effect of determining a transmission rate or a coding method with reference to the changed channel state information from the portable terminal device.

In addition, since the data amount, transmission speed, encoding method, etc., transmitted from the base station Node B to the mobile terminal device change due to the channel state change, the operation frequency of the IC driven for data processing in the mobile terminal device is reduced. Therefore, the power consumption of the portable terminal device can be reduced.

Claims (18)

Receiving channel state information (CQI) from the mobile station device to the base station to determine a transmission amount, a transmission speed, and a coding method of data transmitted from the base station Node B to the mobile device; Selecting one of a plurality of transmission modes according to the power consumption of the portable terminal apparatus by the portable terminal apparatus, and And changing the channel state information (CQI) by the portable terminal device by a one-to-one mapped value with the selected transmission mode. The channel state information (CQI) for determining the transmission amount, transmission rate, and the number of channels allocated from the base station (Node B) to the mobile terminal device is, for each of a plurality of transmission modes according to the power consumption by the mobile terminal device. A step of being calculated and changed by the set change value, Transmitting the changed channel state information from a portable terminal device to a base station Node B; Determining, by the base station Node B, a transmission amount, a transmission rate, and the number of allocated channels based on the changed channel state information; And transmitting data from the base station (Node B) to the terminal apparatus using the determined transmission scheme. The method according to claim 1 or 2, And the transmission mode is selected from among an optimal battery mode, a maximum performance mode, and a general mode. The method according to claim 1 or 2, And changing the channel state information (CQI), the amount of data received by the terminal device is reduced, the method of changing channel state information and data transmission method of the fast downlink packet. The method of claim 3, In the maximum performance mode, the channel state information of the fast downlink packet access characterized in that the value for changing the channel state information (CQI) is set to '1' and the same value is applied to the channel state information (CQI) before the change. Modification method and data transmission method. The method according to claim 1 or 2, If the changed value of the channel state information (CQI) is '0' channel state information change method and data transmission method of fast downlink packet access to automatically change to the channel state information '1' to enable the lowest transmission. Receiving the changed information CQI of the channel state information CQI for determining the transmission amount, transmission speed, and number of channels allocated from the base station Node B to the portable terminal device, Based on the changed channel state information, the base station changing the transmission amount, transmission rate and number of channels allocated to the channel state information (CQI), And transmitting data from the base station Node B to the portable terminal device according to the changed information. delete The method according to claim 2 or 7, And changing the channel state information (CQI), wherein only the amount of data transmission is changed. The method according to claim 2 or 7, And changing the channel status information (CQI), the number of channels remains the same or changed. The transmission of any one of a plurality of transmission modes according to the power consumption of the mobile terminal device, the channel state information value for determining the transmission amount, transmission speed and the number of channels allocated from the base station (Node B) to the mobile terminal device A mobile terminal device that changes depending on the mode, and Based on the changed channel state information value, the amount of data transmission rate, transmission speed and the number of allocated channels are determined, and according to the fast downlink packet access comprises a base station (Node B) for transmitting data to the portable terminal device accordingly. Communication system. 12. The method of claim 11, The portable terminal apparatus includes: A mode selection unit for selecting one or more transmission modes provided to the portable terminal device; A memory for storing change values mapped to the transmission mode for changing channel state information (CQI) of the portable terminal device; And a control unit for controlling to change the channel state information (CQI) by a change value according to a transmission mode selected by the mode selection unit. 13. The method of claim 12, And said transmission mode comprises an optimal battery mode, a maximum performance mode, and a normal mode. The method according to claim 12 or 13, The control unit reduces the data transmission amount, the data transmission rate, and the number of allocated channels by referring to the changed channel state information value when the transmission mode is the optimum battery mode and the normal mode. . The method according to claim 12 or 13, And when the transmission mode is the maximum performance mode, the controller transmits data by applying the same channel state information (CQI) value before the change. 13. The method of claim 12, And the control unit automatically changes the channel state information to '1' so that the lowest transmission is possible when the changed value of the channel state information (CQI) is '0'. 13. The method of claim 12, And said memory is a flash memory. 12. The method of claim 11, The base station (Node B), A channel state information analysis unit for extracting changed channel state information received from the portable terminal device to analyze a wireless environment; And a decision unit for determining a transmission speed and an encoding method for transmitting data to the portable terminal device in consideration of the channel state information.

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