KR20050118071A - Method and apparatus for reporting transmit status information in a mobile communication system for uplink packet service - Google Patents

Abstract

In the present invention, it is assumed that an enhanced uplink dedicated transport channel (hereinafter referred to as 'EUDCH') is used for uplink data transmission in an asynchronous code division multiple access system. When the scheduler of the base station receives the state of the EUDCH packet data buffer and the transmission power state information, etc. from the terminal to perform scheduling operations such as transmission timing and data rate allocation of EUDCH packet data, the transmission start / transmission of the transmission power state information is performed. We propose a technique to efficiently carry out the process of continuation / shutdown.

Description

TECHNICAL AND APPARATUS FOR REPORTING TRANSMIT STATUS INFORMATION IN A MOBILE COMMUNICATION SYSTEM FOR UPLINK PACKET SERVICE}

The present invention relates to a mobile communication system supporting an uplink packet transmission service, and more particularly, to a method and apparatus for efficiently notifying transmission power information of a user terminal. The mobile communication system has evolved from the early voice-oriented service to a high-speed, high-quality third generation mobile communication system for providing data and multimedia services. The third generation mobile communication system refers to a mobile communication method that supports not only voice service but also packet service, and uses a CDMA method. The third-generation mobile communication system, a base station (hereinafter referred to as "Node B quot;) of 3GPP European and Japanese type standard method that is based on the asynchronous between (3 ^rd Generation Project Partnership, or UMTS), and based on the synchronization between the Node B in the US-standard way for a ^{3GPP2 (3 rd Generation Project Partnership 2} , or CDMA2000).

Currently, the third generation mobile communication system, which is divided into asynchronous (3GPP) and synchronous (3GPP2), is standardized for high-speed, high-quality wireless data packet service. For example, in 3GPP, a standardization operation for a high speed downlink packet access (HSDPA) method is in progress, and in 3GPP2, a standardization operation for 1xEV-DV is in progress. This standardization work is a representative proof of the effort to find a solution for the high-speed, high-quality wireless data packet transmission service of 2Mbps or more in the third generation mobile communication system.

In 3GPP, an enhanced uplink dedicated channel (hereinafter referred to as "UE") as well as a high-speed packet transmission from a UE B to a UE B as well as a high-speed packet transmission from a UE to a Node B. EUDCH ") is further proposed.

The EUDCH scheme has been proposed to improve the performance of packet transmission by introducing a new technology in reverse communication in an asynchronous code division multiple access mobile communication system. In the EUDCH technology, an adaptive modulation and coding (AMC) technique and a hybrid automatic re-transmission request (HARQ) technique, which is used as an existing HSDPA technique, is applied. Therefore, the base station (hereinafter referred to as "Node B") should transmit an ACK (acknowledge) or NACK (negative acknowledgment) signal to the UE depending on whether the received data decoding is successful.

However, in order to support the EUDCH, a short frame having a TTI shorter than a transmission time interval (hereinafter, referred to as a "TTI") used in the HSDPA method for transmitting a high-speed packet by rapidly reflecting the state of a reverse channel ( short frame). That is, the EUDCH scheme and the HSDPA scheme will have a difference in a period for performing the AMC scheme and the HARQ scheme. The TTI may be defined as a unit in which one data block is transmitted in a physical channel. As an example, the TTI in the EUDCH scheme may be defined as 2 ms.

Therefore, for the EUDCH scheme, scheduling of a reverse channel for allocating an appropriate resource for each cell together with the above-described AMC scheme, HARQ scheme, and short TTI should be performed. The scheduling of the reverse channel is required for efficient use of limited radio resources.

Typically the data rate for the reverse channel is determined by the UE within the upper limit of a predetermined possible data rate. The upper limit of the data rate is provided to the UE by a Radio Network Controller (hereinafter referred to as "RNC"). That is, the data rate for the existing reverse channel has not been adjusted by the Node B. However, for EUDCH, whether the uplink data is transmitted and the upper limit of the available data rate are determined by the Node B. The determined information is transmitted to the UE as a scheduling command. The UE determines a data rate to use for the EUDCH according to the scheduling command.

 FIG. 1 is a diagram illustrating a situation in which several UEs exist for performing uplink transmission with one Node B.

Referring to FIG. 1, UEs 110, 112, 114, and 116 transmit packet data at different transmission powers 120, 122, 124, and 126 according to a distance from the Node B 100. The UE 110 farthest from the Node B 100 transmits packet data at the highest transmission power 120. The UE 114 closest to the Node B 100 transmits packet data at a relatively low transmit power 124. The transmission power and the packet data rate applied in the UEs 110, 112, 114, and 116 may vary according to a scheduling algorithm applied in the Node B 100.

FIG. 2 illustrates a process in which a UE is allocated a data rate for EUDCH packet data transmission from a Node B and transmits packet data using the allocated data rate.

Referring to FIG. 2, in step 204, an EUDCH is configured between the Node B 200 and the UE 202. That is, step 204 includes transmitting and receiving messages through a dedicated transport channel. In step 206, the UE 202 transmits information about a required data rate and information indicating an uplink channel condition to the Node B 200 in step 206. Information indicating the uplink channel status includes an uplink transmission power transmitted by the UE 202 and a transmission power margin of the UE 202.

The Node B 200 receiving the uplink transmission power may estimate an uplink channel condition by comparing the uplink transmission power and the reception power. That is, if the difference between the uplink transmission power and the uplink reception power is small, the situation of the uplink channel is considered good. If the difference between the transmission power and the reception power is large, the situation of the uplink channel is considered poor. When the UE 202 transmits a transmission power margin to estimate the situation of the uplink channel, the Node B 200 subtracts the transmission power margin from the maximum possible transmission power of a UE that is already known. The transmission power can be estimated. The Node B 200 determines the maximum possible data rate by using the estimated channel condition of the UE, a transmission power margin, and information on the data rate required by the UE 202.

The determined maximum data rate is notified to the UE 202 in step 208. The UE 202 determines a data rate of packet data to be transmitted within a range of the maximum data rate notified. In step 210, the UE 202 transmits packet data to the Node B 200 at the determined data rate.

If the Node B 200 successfully decodes the packet data without error, the Node B 200 transmits an acknowledgment (ACK) signal to the UE 202 in step 212. Upon receiving the ACK signal, the UE 202 transmits new packet data to the Node B 200. However, if the Node B 200 fails to decode the packet data, the Node B 200 transmits a negative acknowledgment (NACK) signal to the UE 202 in step 212. Upon receiving the NACK signal, the UE 202 retransmits the packet data previously transmitted in step 210.

The uplink physical channel for the above-mentioned EUDCH service includes a dedicated physical data channel (DPDCH), a dedicated physical control channel (DPCCH), and a high speed dedicated physical channel for HSDPA services. Control Channel (HS-DPCCH), a dedicated physical data channel (EU-DPDCH) for EUDCH services, and a dedicated physical control channel (EU-DPCCH).

Specifically, a transport format identifier (E-TFRI) for packet data transmitted on the EU-DPDCH is transmitted through the EU-DPCCH. In addition, transmission status information according to packet data transmission in the UE is transmitted to the base station through the EU-DPCCH. The transmission status information includes a buffer status (BO, Buffer Occupancy) and transmit power status (TPS) information.

On the EU-DPDCH, packet data is transmitted using a data rate determined by scheduling information. The DPDCH only supports BPSK modulation. However, the EU-DPDCH may support not only the BPSK but also QPSK, 8PSK, etc. to increase the data rate while maintaining the number of spreading codes transmitted simultaneously.

As described above, the Node B receives information such as BO and TPS from the UE to perform scheduling operations such as transmission timing and data rate allocation of EUDCH packet data. At this time, in the case of the BO of the information is generally reported to the Node B only when new data occurs in the EUDCH packet data buffer of the UE. In contrast, the TPS information is periodically reported regardless of occurrence of new data.

Accordingly, the UE continuously reports the TPS information even when there is no packet data to be transmitted to the EUDCH packet data buffer, thereby increasing the uplink interference level. In addition, unnecessary power is consumed due to demodulation / decoding of the TPS periodically transmitted from the transmitter of the UE and the receiver of the Node B.

Accordingly, an object of the present invention is to propose an apparatus and method for efficiently transmitting buffer state and transmission power state information only when necessary in a mobile communication system supporting uplink packet service. .

Another object of the present invention is to propose an apparatus and method for ensuring stable transmission and reception between a UE and a Node B in transmitting buffer state and transmission power state information only when necessary in a mobile communication system supporting an uplink packet service.

Another object of the present invention is to propose an apparatus and method for reducing signaling overhead in transmitting buffer state and transmit power state information only when necessary in a mobile communication system supporting uplink packet service.

Another object of the present invention is an apparatus and method for efficiently using radio resources by reducing signaling overhead in transmitting buffer state and transmit power state information only when necessary in a mobile communication system supporting uplink packet service. In the proposal.

In accordance with another aspect of the present invention, a method for efficiently transmitting packet data by a user terminal in a mobile communication system supporting an uplink packet service is provided. Transmitting a message including a buffer state and a transmission power state information to a base station when the set value is exceeded, and notifying the start of transmission of the uplink packet data; and periodically transmitting the message to transmit the uplink packet data. If the amount of the data is smaller than the preset value, sending a message to the base station to terminate the transmission of the uplink packet data. And a notice box.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. 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.

In order to explain the concept of MAC-e control signaling proposed in the present invention, FIG. 3 shows a structure of a MAC-e PDU delivered from a MAC layer to a physical layer.

Referring to FIG. 3, EUDCH packet data is carried in the data field 304 of the MAC-e PDU 300, and HARQ-related information and data of the EUDCH data carried in the data field 304 are included in the header field 302. Information on the extraction of the information is displayed. In the present invention, the BO and TPS information of the UE is transmitted in the header field 302 or the data field 304. That is, BO information requiring aperiodic reporting can be transmitted through MAC-e control signaling for transmitting a control information message using the EUDCH packet as described above. The MAC-e PDU 300 is provided to the physical layer and is transmitted to Node B after channel coding and physical channel mapping are performed.

4 illustrates a transmitter structure of a UE supporting EUDCH service.

Referring to FIG. 4, an EUDCH transmission controller 404 generates an EU-DPCCH for transmitting BO and TPS necessary for Node B control scheduling to the Node B. In addition, the EUDCH transmission controller 404 determines the E-TFRI and outputs the determined E-TFRI to be transmitted to the Node B through the EU-DPCCH. In this case, the packet data transmission format is determined using the maximum data rate allowed by the scheduling allocator 402.

The EUDCH packet transmitter 406 receives the packet data of the amount specified by the transmission format of the forwarded EUDCH packet data from the EUDCH data buffer 400. The received packet data is transmitted to the Node B through EU-DPDCH after performing channel coding and modulation using the EUDCH packet data transmission format.

Meanwhile, the data of the DPDCH is spread at the chip rate using the OVSF code in the multiplier 422 and then multiplied by the channel gain in the multiplier 424. Data of the DPDCH multiplied by the channel gain is input to summer 426. The control information of the EU-DPCCH is spread at the chip rate using the OVSF code in the multiplier 408 and then multiplied by the channel gain in the multiplier 410. The control information of the EU-DPCCH multiplied by the channel gain is input to the summer 426. The summer 426 adds the data of the DPDCH and the control information of the EU-DPCCH and then configures an I channel.

In addition, it is assumed that the transmission symbol of the EU-DPDCH is transmitted as a complex symbol. In other words, when the transmission symbol of the EU-DPDCH is modulated using BPSK, a real value is obtained. However, when modulation is performed using QPSK and 8PSK, the transmission symbol has a complex value. The modulator 412 converts the packet data delivered from the EUDCH packet transmitter 406 into a complex symbol stream of I + jQ and then passes it to the multiplier 414. The multiplier 414 spreads the modulation symbols at chip rate by the OVSF code. The output of the multiplier 414 is multiplied by the channel gain in multiplier 418.

The control information of the DPCCH is spread at the chip rate using the OVSF code in the multiplier 428 and then multiplied by the channel gain in the multiplier 430. The control information multiplied by the channel gain is input to a summer 436. The control information of the HS-DPCCH is spread at the chip rate using the OVSF code in the multiplier 432 and then multiplied by the channel gain in the multiplier 434. Control information multiplied by the channel gain is input to the summer 436. The summer 436 adds the input control information of the DPCCH and the control information of the HS-DPCCH and forms a Q channel. The output of summer 436 is multiplied by imaginary number by multiplier 438 and then passed to summer 420.

The summer 420 receives one of the output of the summer 426, the output of the multiplier 418, and the output of the multiplier 438, and adds the complex symbol string. The complex symbol string is passed to a multiplier 442. The multiplier 442 scrambles the complex symbol string using a scrambling code. The scrambled complex symbol string is converted into pulse form in the pulse generator 444 and then transmitted to the Node B through the antenna 448 via the RF 446.

In the detailed description of the present invention to be described below, the UE reports the transmission power state information only when data exists in the EUDCH packet data buffer. For this purpose, a specific operation for starting the transmission power state report according to the buffer state, continuing the transmission power state report and ending the transmission power state report should be posted. As a technique for efficiently performing the start / continue / end of the TPS report, the present invention proposes the following methods for each step.

Hereinafter, a start / continue / end of a transmission power state report according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1, start

As a method for starting a transmission power state report according to an embodiment of the present invention, the following two methods may be proposed.

Method 1: Simultaneous Transmission Method Using MAC-e Signaling of BO and TPS

If the data of the EUDCH packet data buffer exceeds the threshold for scheduling, the UE includes the BO and the TPS information in the same MAC-e PDU and transmits it to Node B through MAC-e signaling. Thereafter, the TPS is periodically transmitted through physical layer signaling.

Method 2: transmitting only BO using MAC-e signaling

If the data of the EUDCH packet data buffer exceeds the threshold for scheduling, the UE transmits only the BO information to the Node B through MAC-e signaling. After the report, the TPS is periodically transmitted through physical layer signaling.

2. Continue

As a method of continuing the transmission power state report according to an embodiment of the present invention, the UE periodically reports the TPS to the Node B through physical layer signaling. The bo information is reported to the Node B through MAC-e signaling after a threshold test when new data is generated in the buffer. The BO information may be the total amount of data in the buffer currently storing the EUDCH packet or the amount of data newly generated since the previous BO information report.

3. Termination

As a method of ending the transmission power state report according to an embodiment of the present invention, the following three methods may be proposed.

Method 1: UE notifies Node B

If the amount of data in the EUCDH packet data buffer is less than the threshold for scheduling, the UE informs Node B to terminate the TPS transmission. (If the threshold is 0, it means that there is no more data in the buffer.)

Method 2: Implicit Indication

When the amount of data in the EUCDH packet data buffer is smaller than the threshold for scheduling, the UE terminates the TPS transmission without notifying the Node B. The Node B no longer performs TPS reception when the amount of data in the EUCDH packet data buffer of the UE is smaller than a threshold for scheduling based on the BO report of the UE and the received EUDCH data packet amount.

Method 3: Node B instructs UE

The Node B instructs the UE to terminate TPS transmission when the amount of data in the EUCDH packet data buffer of the UE is smaller than the threshold for scheduling based on the amount of EUDCH data packets received and received by the UE.

Meanwhile, in the above-described processes, the UE considers the buffer state of the UE, the transmission power margin, the applicable E-DCH transport channel format, etc. together, and corresponds to the maximum transmittable data rate (E-TFI). ) Value or corresponding scheduling information may be transmitted instead of the TPS information. Correspondingly, when the Node B receives the E-TFI information, the Node B will directly know the maximum data rate that the UE can apply at the scheduling time from the E-TFI information. Accordingly, the Node B may transmit a scheduling command considering the data rate to the UE.

Hereinafter, specific operations of the embodiments of the present invention will be described. Each of the following embodiments is a combination of the start / continue / end methods of the TPS report described above, it will be apparent to those skilled in the art that other combinations other than the embodiments described below are possible. In the following embodiments, instead of the TPS, an E-TFI value or corresponding scheduling information may be transmitted.

First embodiment

Hereinafter, the first embodiment of the present invention will be described in detail a simultaneous transmission scheme using the MAC-e signaling of the BO and TPS and the termination notification scheme by the UE. That is, the transmission power state report is started by the simultaneous transmission scheme using the MAC-e signaling of the BO and the TPS, and the transmission power state report is terminated by the termination notification scheme by the UE.

5 is a diagram illustrating transmission timing of a BO and a TPS according to the first embodiment of the present invention.

Referring to FIG. 5, if there is no data to transmit in the EUDCH packet data buffer, the UE does not start reporting the BO and the TPS (reference numeral 500). Accordingly, Node B does not transmit scheduling assignment information to the UE (reference numeral 502).

The UE starts transmission of BO information and TPS information when there is data exceeding a predetermined threshold value in the EUDCH packet data buffer at the time 504. That is, when the threshold is 0, the UE starts transmitting the BO and TPS information as long as data is newly generated in the buffer. Reference numerals 506 and 508 indicate the start time point of transmitting the BO information and the TPS information. When the BO information is informed to Node B through MAC-e control signaling, TPS information is also carried on the same MAC-e PDU. This means that the Node B is informed of the start of the TPS report. In other words, it is called 'start of transmission power status report'.

Thereafter, the BO information is transmitted when new data is generated in the data buffer and the amount of data in the buffer is larger than a threshold for scheduling. The TPS information is transmitted by a predetermined period (T _TPS ) 520. This is called continuation of the transmission power status report. Transmission of the TPS information by the predetermined period is shown at 512, 514, 516, 518 and 532. Transmission of the BO information is shown at 522 and 524. The transmission period and offset of the TPS information are transmitted from the Radio Network Controller (hereinafter referred to as 'RNC') to the UE and Node B through Radio Resource Control (RRC) and Iub signaling. It is known in advance.

Meanwhile, as described above, when the Node B receives BO information and TPS information from the UE, the Node B transmits scheduling allocation information corresponding thereto through a predetermined downlink channel. Transmission of the scheduling assignment information is shown at 510 and 528.

The UE continuously monitors the data buffer and transmits an end indicator to the Node B at reference numeral 530 when there is a small amount of data in the data buffer. In this case, the termination indicator may be a separate indicator signal directly indicating that the TPS report will be terminated. As another example, the BO information may be implicitly terminated by transmitting BO information indicating that the amount of data present in the current buffer is smaller than the threshold. When the Node B receives the termination indicator, the Node B can know that no TPS information will be reported from the UE any more because there is a small amount of data in the UE. This is called the end of the transmission power status report.

6 is a diagram illustrating an operation performed by a UE for the first embodiment of the present invention. In this case, it is assumed that data of the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of BO information and TPS information has not started.

Referring to FIG. 6, the UE continuously observes the amount of data stored in the EUDCH packet data buffer in step 600. In step 602, it is determined whether the amount of data stored in the EUDCH packet data buffer exceeds the threshold THRES _buffer for scheduling due to the generation of new data.

If the amount of data to be transmitted exceeds the threshold THRES _buffer , the UE proceeds to step 604 to transmit the BO information and the TPS information to the Node B, thereby notifying the start of the TPC report. In this case, the BO information and the TPS information are reported through MAC-e control signaling using EUDCH packet data transmission. The BO information and the TPS information are transmitted on the same MAC-e PDU.

However, if data that does not exceed the threshold exists in the data buffer, autonomous transmission is possible in which the UE transmits data in the data buffer by itself without scheduling of the Node B. When the spontaneous transmission of the UE is impossible, it corresponds to the case where the threshold is 0.

In step 606, the UE monitors whether an ACK signal is received in response to the transmitted BO information and the TPS information. If a NACK signal other than the ACK signal is received, the UE proceeds to step 604 to retransmit the previously transmitted BO information and TPS information. Otherwise, if the ACK signal is received, the UE proceeds to step 608 to continuously observe the state of the data buffer. Thereafter, the UE determines whether there is an amount of data exceeding a predetermined threshold in the data buffer in step 610. If the amount of data exceeding a predetermined threshold exists in the data buffer, the UE proceeds to step 612 to determine whether a period for transmitting the TPS information, that is, the timing of transmitting the TPS information. If it is confirmed that the transmission timing of the TPS information, the UE transmits the TPS information in step 614.

When the UE transmits the TPS information or determines that it is not the transmission timing of the TPS information, the UE checks whether new data is generated in the data buffer in step 616. If new data is generated in the data buffer, the UE transmits BO information considering the newly generated data in step 618. If no new data is generated or the BO information is transmitted, the UE proceeds to step 608 to continuously monitor the data buffer.

On the other hand, if there is no data exceeding a predetermined threshold value in the data buffer in step 610, the UE proceeds to step 620. In step 620, the UE ends the transmission of the TPS information and transmits a TPS information report end indicator to the Node B indicating that the TPS information is no longer transmitted. In step 622, the UE determines whether to continue packet data service by EUDCH. If the continuation of the packet data service is determined, the process proceeds to step 600.

7 is a diagram illustrating an operation performed by a Node B for the first embodiment of the present invention. In this case, it is assumed that data in the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of BO information and TPS information has not started.

Referring to FIG. 7, the Node B receives an EUDCH packet in step 1100. Thereafter, the process proceeds to step 1102 to check whether the BO information and the TPS information are detected. If the BO information and the TPS information are not detected, the process proceeds to step 1100 to continuously receive the EUDCH packet. If the BO information and the TPS information are detected, the Node B proceeds to step 1104 and transmits an ACK signal. In step 1106, the scheduling assignment signal corresponding to the TPS information is generated and transmitted to the UE.

The Node B determines whether it is time to receive TPS information in step 1108, and demodulates and decodes the TPS information received in step 1110 when the TPS information is received.

In step 1108 or 1110 to 1112, after receiving the EUDCH packet, it is checked whether BO information or TPS end indicator is detected in steps 1114 and 1118. If it is checked in step 1114 that the BO information exists, the Node B decodes the BO information in step 1116. If the TPS end indicator is not detected in step 1118, the flow proceeds to step 1106.

If the TPS end indicator is detected, the Node B proceeds to step 1120 to terminate reception of the TPS information. In step 1122, it is checked whether the EUDCH packet service continues. If it is determined that the EUDCH packet service continues, the Node B proceeds to step 1100.

The operation according to the first embodiment of the present invention described above is as follows.

1. Start: Start TPS report through MAC-e signaling of BO and TPS

Initially, there is no data in the EUDCH packet data buffer of the UE and the BO and TPS reporting has not started yet (500). Accordingly, scheduling assignment information is not transmitted to the UE even in the Node B (502). When the UE continues to observe the EUDCH packet data buffer (600) and new data is generated to exceed the threshold THRES _buffer for scheduling (504,602), the UE sends the BO information to Node B for signaling MAC-e control using EUDCH packet data transmission. Report via 506. In this situation, when data smaller than the threshold exists in the buffer, the UE may transmit data in the buffer by itself without scheduling of Node B. When the voluntary transmission of the UE is impossible, the threshold is 0. Corresponds to When the UE informs the Node B of the BO information through MAC-e control signaling, the UE notifies the Node B of the start of the TPS report by transmitting the TPS information to the same MAC-e PDU (508 and 604). After receiving the EUDCH packet including the BO information and the TPS information (1100), the Node B learns that the TPS information is loaded through decoding of the MAC-e PDU of the packet (1102). If the Node B successfully receives the MAC-e PDU, it transmits an ACK signal to the UE (1104), thereby enabling the UE to know that the Node B has successfully received TPS information (606). Another advantage of the signaling method as described above is that the UE starts transmitting TPS information when the first BO information is transmitted, so that Node B can quickly perform scheduling and transmit scheduling allocation information to the UE (510, 1106).

2. Continue

If the TPS transmission start notification process is successfully performed, the UE transmits TPS information to a fixed period T _TPS 520,612 through physical layer signaling (512,514,516,518,532,614), and Node B also receives the TPS information in the period (1108). , 1110). The TPS transmission period and offset are transmitted to the UE and the Node B by a Radio Network Controller (RNC) through Radio Resource Control (RRC) and Iub signaling. It is known in advance.

The TPS physical layer signaling may be performed through EU-DPCCH, which is a control physical channel dedicated to EUDCH service. Meanwhile, in the case of BO, when new data is generated in the EUDCH data buffer of the UE (616), a predetermined threshold test is performed and then transmitted through MAC-e control signaling (522,524,618). When the Node B receives the newly transmitted BO information 522 after reporting the first BO information (1114 and 1116), the Node B receives new scheduling assignment information based on the BO information and the recently received TPS information. Transmit (528, 1106). As described above, the UE periodically reports the TPS information to the Node B through physical layer signaling, and the BO reports the MAC-e control signaling whenever necessary.

3. Termination: The UE notifies the Node B of the termination of reporting using MAC-e or physical layer signaling.

The UE ends reporting of the TPS information when the amount of data in the EUCDH packet data buffer is smaller than the threshold for scheduling (612). When the TPS report is terminated, the UE no longer transmits TPS information and sends a termination indicator to the Node B (620). When the Node B receives the TPS report end notification from the UE (1118), the Node B no longer demodulates the TPS information (1120).

The following two signaling methods may be proposed to perform the termination notification operation.

1) MAC-e control signaling

The UE notifies the Node B of termination via MAC-e control signaling. For example, when transmitting the EUDCH packet, if the amount of data in the EUCDH packet data buffer is smaller than the threshold for scheduling (530), the node B is notified by sending an end indicator to the MAC-e header of the EUDCH packet (532). Can be. As described above, as the termination indicator, a separate indicator indicating directly that the TPS report is to be terminated may be used, or BO information indicating that the amount of packet data present in the current buffer is smaller than a threshold may be used. When the UE receives the ACK signal for the EUDCH packet from the Node B, it can be known that the Node B has normally received the termination indicator. On the other hand, if new data is generated in the UE buffer after sending the end indicator in the process, it is enough to start again from the report start process described in the first start step.

2) physical layer signaling

(1) Separate definition of TPS value for termination indicator

When notifying the end of the TPS information report using physical layer signaling, the UE sends the termination notification information to the Node B through the EUDCH service dedicated control physical channel after the last EUDCH packet is successfully transmitted. When transmitting TPS information for the termination notification, one value may be set for the termination indicator so that the UE transmits the corresponding TPS value when the UE intends to transmit the termination indicator to the Node B. The Node B recognizes that the UE will no longer send TPS information when the received TPS value is a value set for the termination indicator and does not perform TPS information reception thereafter.

(2) Configure separate physical channel field for end indicator

One field of the EUDCH dedicated control physical channel is set as a dedicated field for sending an end indicator. When the UE wants to terminate the TPS information report, the UE sets a value indicating termination notification in the field and transmits it to the Node B. Node B knows the end of the TPS information after normal demodulation of the field.

Second embodiment

In the second embodiment of the present invention, an implicit start notification using BO information and an implicit end notification using BO information will be described in detail.

8 is a diagram illustrating transmission timing of a BO and a TPS according to a second embodiment of the present invention.

Referring to FIG. 8, if there is no data to transmit in the EUDCH packet data buffer, the UE does not start reporting BO information. Therefore, Node B does not transmit scheduling assignment information to the UE.

The UE starts transmitting BO information when there is data exceeding a predetermined threshold in the EUDCH packet data buffer at the point of reference 700. Reference numeral 702 indicates the start time of the BO information transmission. The BO information is reported to the Node B through MAC-e control signaling. This means that the Node B is informed of the start of the TPS report. In other words, it is called 'start of transmission power status report'. This is because the Node B can confirm that data to be transmitted from the UE has exceeded a predetermined threshold through the BO information. That is, the Node B can know that transmission of the TPC information will be started when the amount of data to be transmitted by the UE exceeds a predetermined threshold.

Thereafter, the BO information is transmitted after a threshold test when new data is generated in the data buffer, and the TPS information is transmitted by a predetermined period T _TPS . This is called continuation of the transmission power status report. Accordingly, the Node B receives TPC information transmitted at a predetermined period and transmits scheduling assignment information to the UE in response to the received TPC information.

The UE continuously monitors the data buffer and terminates periodic reporting of the TPS information if there is a small amount of data in the data buffer. Meanwhile, the Node B can know that the reporting of the TPS information is terminated by the BO information and the amount of data received by the Node B. This is called the end of the transmission power status report.

As another example, the Node B may transmit a TPS information report end indicator to the UE. In this case, if the UE receives the TPS information report end indicator in a situation where the amount of data to be transmitted exceeds a predetermined threshold, the UE may perform the TPS information report from the start process.

9 illustrates an operation performed by a UE for a second embodiment of the present invention. In this case, it is assumed that data of the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of TPS information has not started.

Referring to FIG. 9, in step 800, the UE continuously observes the amount of data stored in the EUDCH packet data buffer. In step 802, it is determined whether the amount of data stored in the EUDCH packet data buffer exceeds the threshold THRES _buffer for scheduling due to the generation of new data.

If the amount of data to be transmitted exceeds the threshold THRES _buffer , the UE proceeds to step 804 and transmits BO information to the Node B to notify the start of the TPC report. In this case, the BO information is reported through MAC-e control signaling using EUDCH packet data transmission.

In step 806, the UE monitors whether an ACK signal is received in response to the transmitted BO information. If a NACK signal other than the ACK signal is received, the UE proceeds to step 804 and retransmits the previously transmitted BO information. Otherwise, if the ACK signal is received, the UE proceeds to step 808 to continuously observe the state of the data buffer. Thereafter, in step 814, the UE determines whether an amount of data exceeding a predetermined threshold exists in the data buffer. If the amount of data exceeding a predetermined threshold exists in the data buffer, the UE proceeds to step 810 to determine whether a period for transmitting TPS information, that is, timing of transmitting TPS information. If it is confirmed that the transmission timing of the TPS information, the UE transmits the TPS information in step 812.

If it is determined that the TPS information is not transmitted or the timing of transmission of the TPS information, the UE proceeds to step 813 to check whether new data has been generated in the data buffer. If new data is generated in the data buffer, the UE transmits BO information considering the newly generated data in step 815. If no new data is generated or the BO information is transmitted, the UE proceeds to step 808 to continuously monitor the data buffer.

On the other hand, if there is no data exceeding a predetermined threshold value in the data buffer in step 814, the UE proceeds to step 816. In step 816, the UE terminates the transmission of the TPS information, and in step 817, determines whether to continue the packet data service by the EUDCH. If the continuation of the packet data service is determined, the process proceeds to step 800.

10 is a diagram illustrating an operation performed by a Node B for a second embodiment of the present invention. In this case, it is assumed that data of the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of TPS information has not started.

Referring to FIG. 10, the Node B receives an EUDCH packet in step 1200. After that, the flow proceeds to step 1202 to check whether the BO information is detected. If the BO information is not detected, the process proceeds to step 1200 to continuously receive the EUDCH packet. If the BO information is detected, the Node B proceeds to step 1204 and transmits an ACK signal. In operation 1206, the Node B checks whether the TPS information is received, and demodulates and decodes the TPS information received in step 1208 when the TPS information is received.

In step 1206 or 1208, the process proceeds to step 1210. After receiving the EUDCH packet, it is checked whether BO information exists in step 1212. If it is checked in step 1212 that the BO information exists, the Node B decodes the BO information in step 1214. If the BO information does not exist or the decoding of the BO information is completed in step 1212, the Node B proceeds to step 1216. In step 1216, the Node B generates a scheduling assignment signal corresponding to the TPS information and transmits it to the UE.

The Node B estimates the amount of data to be transmitted from the UE based on the BO information, and checks whether the estimated amount of data is smaller than a predetermined threshold THRES _buffer in step 1218. If the estimated amount of data is not smaller than a predetermined threshold THRES _buffer , the Node B returns to step 1205. However, if the estimated amount of data is smaller than the predetermined threshold THRES _buffer , reception of the TPS information is terminated in step 1220. In step 1222, it is checked whether the EUDCH packet service continues. If it is determined that the EUDCH packet service continues, the Node B proceeds to step 1200.

The operation according to the first embodiment of the present invention described above is as follows.

1. Start: The BO information is used to inform the start notification implicitly.

Unlike the case in which the start notification is performed using the MAC-e control signaling in the above-described first embodiment, the UE does not transmit a special start indicator to the Node B in the second embodiment.

If the UE continues to observe the EUDCH packet data buffer (800) and new data is generated and exceeds the threshold for scheduling (700,802), the UE reports the BO information to the Node B through MAC-e control signaling (702,804) but not the TPS. Information is not transmitted with the signaling. However, the Node B can know that the UE will start TPS transmission if the BO 1202 value received from the UE is greater than the threshold for scheduling. In addition, the UE receives an ACK signal transmitted from the Node B to the UE after decoding the MAC-e PDU containing the BO information (1204) (806), so that the Node B normally receives the BO information and is ready to receive the TPS information. I can see the fact.

2. Continue

The process of transmitting the BO and TPS information to the Node B by the UE after the initial BO transmission 702 of the UE described above is the same as that of the first embodiment. At the first TPS information transmission timing 704 after the initial BO information transmission after the initial state, the UE carries TPS information through the EUDCH dedicated control physical channel (704), and Node B is initiating the above-described TPS information transmission. The TPS information transmitted by the UE may be received 1208 through an implicit notification process. After receiving the TPS information, the Node B transmits scheduling allocation information to the UE (720 and 1216). The Node B receives the TPS information transmitted by the UE 706, 708, 710, 712, 812 at regular time intervals 810 from a time point of transmitting the first TPS information.

3. Termination: Implicit termination notification using BO information.

In order for the UE and the Node B to terminate transmission and reception of the TPS implicitly, the BO information and the amount of EUDCH packet data received by the Node B may be used. The UE terminates reporting TPS information when the amount of data in the EUCDH packet data buffer is less than the threshold for scheduling (714, 814) (716, 816). However, the UE does not transmit the end indicator of the TPS information report to the Node B. The Node B compares the most recently received BO information 718 with the amount of EUDCH data received after the BO information and if the amount of data in the EUCDH packet data buffer of the UE is smaller than the threshold for scheduling (1218), the UE further It is assumed that the TPS is not transmitted, and the reception of the TPS is not performed (1220). By the above-described process, the report of the TPS information may be implicitly terminated. Meanwhile, in the above process, the Node B may inform the UE that the reception of the TPS information is finished through the EUDCH dedicated physical control channel. If there is data exceeding the threshold in the buffer of the UE, if Node B sends an end indicator, the UE may start again from the start of the TPS information report.

Third embodiment

In the third embodiment of the present invention, an implicit start notification using BO information and an end notification by Node B will be described in detail.

11 is a diagram illustrating transmission timing of a BO and a TPS according to a third embodiment of the present invention.

Referring to FIG. 11, if there is no data to transmit in the EUDCH packet data buffer, the UE does not start reporting BO information. Therefore, Node B does not transmit scheduling assignment information to the UE.

The UE starts transmission of BO information when data exceeding a predetermined threshold exists in the EUDCH packet data buffer. The BO information is reported to the Node B through MAC-e control signaling. This means that the Node B is informed of the start of the TPS report. In other words, it is called 'start of transmission power status report'. This is because the Node B can confirm that data to be transmitted from the UE has exceeded a predetermined threshold through the BO information. That is, the Node B can know that transmission of the TPC information will be started when the amount of data to be transmitted by the UE exceeds a predetermined threshold.

Thereafter, the BO information is transmitted after a threshold test when new data is generated in the data buffer, and the TPS information is transmitted by a predetermined period T _TPS . This is called continuation of the transmission power status report. Accordingly, the Node B receives TPC information transmitted at a predetermined period and transmits scheduling assignment information to the UE in response to the received TPC information.

The Node B can know that the reporting of the TPS information is terminated by the BO information and the amount of data received by the Node B. This is called the end of the transmission power status report. When this situation occurs, the Node B transmits a TPS information report end indicator to the UE. The UE terminates periodic reporting of the TPS information when the TPS information report end indicator is received from the Node B in a situation of continuously transmitting the TPS information. In this case, if the UE receives the TPS information report end indicator in a situation where the amount of data to be transmitted exceeds a predetermined threshold, the UE may perform the TPS information report from the start process.

12 is a diagram illustrating an operation performed by a UE for the third embodiment of the present invention. In this case, it is assumed that data of the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of TPS information has not started.

12, the UE continuously observes the amount of data stored in the EUDCH packet data buffer in step 1000. In step 1002, it is determined whether the amount of data stored in the EUDCH packet data buffer exceeds the threshold THRES _buffer for scheduling due to the generation of new data.

If the amount of data to be transmitted exceeds the threshold THRES _buffer , the UE proceeds to step 1004 and transmits BO information to the Node B to notify the start of the TPC report. In this case, the BO information is reported through MAC-e control signaling using EUDCH packet data transmission.

The UE monitors whether an ACK signal is received in response to the transmitted BO information in step 1006. If a NACK signal other than the ACK signal is received, the UE proceeds to step 1004 and retransmits the previously transmitted BO information. Otherwise, if the ACK signal is received, the UE proceeds to step 1008 to monitor whether the TPS information report end indicator from the Node B is received.

If the TPS information report end indicator is not received, the UE determines whether a period for transmitting TPS information, that is, timing of transmission of TPS information is determined in step 1010. If it is confirmed that the transmission timing of the TPS information, the UE transmits the TPS information in step 1012.

If the UE transmits the TPS information or determines that it is not the transmission timing of the TPS information, the UE checks whether new data has been generated in the data buffer in step 1014. If new data is generated in the data buffer, the UE transmits BO information considering the newly generated data in step 1016. If no new data is generated or if the BO information is transmitted, the UE proceeds to step 1008 to continuously monitor the data buffer.

Meanwhile, if the TPS information report end indicator is received in step 1008, the UE proceeds to step 1018. In step 1018, the UE ends transmission of TPS information, and in step 1020, the UE determines whether to continue packet data service by EUDCH. If the continuation of the packet data service is determined, the process proceeds to step 1000 above.

FIG. 13 is a diagram illustrating an operation performed by a Node B for a third embodiment of the present invention. FIG. In this case, it is assumed that data of the EUDCH packet data buffer of the UE does not exceed a predetermined threshold and thus reporting of TPS information has not started.

Referring to FIG. 13, the Node B receives an EUDCH packet in step 1300. Thereafter, the process proceeds to step 1302 to check whether the BO information is detected. If the BO information is not detected, the process proceeds to step 1300 to continuously receive the EUDCH packet. If the BO information is detected, the Node B proceeds to step 1304 and transmits an ACK signal. In operation 1306, the Node B checks whether the TPS information is received, and demodulates and decodes the TPS information received in step 1308 when the TPS information is received.

In step 1306 or 1308, the process proceeds to step 1310. After receiving the EUDCH packet, it is checked whether BO information exists in step 1312. If it is checked in step 1312 that the BO information exists, the Node B decodes the BO information in step 1314. If the BO information does not exist or decoding of the BO information is completed, the Node B proceeds to step 1316. In step 1316, the Node B generates a scheduling assignment signal corresponding to the TPS information and transmits it to the UE.

The Node B estimates the amount of data to be transmitted from the UE based on the BO information, and determines in step 1318 whether the estimated amount of data is smaller than a predetermined threshold THRES _buffer . If the estimated amount of data is not smaller than a predetermined threshold THRES _buffer , the Node B returns to step 1306. However, if the estimated amount of data is smaller than the predetermined threshold THRES _buffer , in step 1320, after receiving the TPS information, the TPS information report end indicator is transmitted to the UE. In step 1314, it is checked whether the EUDCH packet service continues. If it is determined that the EUDCH packet service continues, the Node B proceeds to step 1300.

The operation according to the first embodiment of the present invention described above is as follows.

1. Start: Only MAC-e signaling of BO start

The UE does not transmit a special start indicator to the Node B by the same method and procedure as the start case of the second embodiment.

2. Continuation: The same method and procedure as the continuation notification case of the first embodiment is performed.

3. Termination: Instructs termination by Node B using physical layer signaling.

In the third embodiment, the Node B directly makes a decision to terminate TPS information reporting and informs the UE of the determination so that it no longer transmits TRS information. Accordingly, the UE continues to transmit TPS information periodically (1014) until it receives a termination instruction from the Node B (1008). The Node B compares the most recently received BO information 900 with the amount of EUDCH data received after the BO information, and when the amount of data in the EUCDH packet data buffer of the UE is smaller than the threshold for scheduling (902, 1318), the TPS The reception of the UE is no longer performed (1320), and the UE instructs to terminate the TPS information report through physical layer signaling (904 and 1322). When the UE receives the TPS information report end indicator (1008), the UE ends the TPS information report (1018). For the physical layer signaling, a downlink control physical channel for EUDCH service may be used. If there is data exceeding the threshold value in the buffer of the UE, if Node B sends an end indicator, the UE may start again from the start of the TPS information report. As described above, one of the advantages of the Node B instructing the UE to terminate the TPS information reporting is that the Node B additionally reports the TPS information according to the needs of the Node B even when the amount of data in the EUCDH packet data buffer of the UE is smaller than the threshold for scheduling. Can be received.

Transmitter structure

14 illustrates a structure of a terminal transmitter according to the technique proposed by the present invention.

Referring to FIG. 14, when new data is input to the EUDCH data buffer 1400 in the initial state, and the BO value exceeds the threshold THRES _buffer 1402 for scheduling, the BO transmission controller 1404 determines that the BO value is MAC. The switch 1406 is turned on to be transmitted to the MAC-e PDU generator 1408 to be transmitted by the control signaling. The MAC-e PDU generated in block 1408 is transmitted to the EU-DPDCH channel after channel coding and physical channel mapping in the EUDCH packet transmitter 1420.

The TPS transmission controller 1410 controls the transmission of the TPS information of the UE. Accordingly, in the first embodiment, when the UE wants to send a TPS information report start notification to the Node B, the UE adjusts the TPS information switch 1412 so that the TPS information measured by the TPS measurement unit 1414 is simultaneously with the BO information. Input to MAC-e PDU generator.

In addition, the TPS transmission controller 1410 inputs the TPS information to the EUDCH dedicated control channel generation block 1416 for each T _TPS , which is a TPS transmission period, to be carried on the EU-DPCCH channel.

On the other hand, when the UE wants to notify the Node B of the end of the TPS transmission report, the TPS transmission controller 1410 generates a TPS report end indicator 1422, and the TPS report end indicator is MAC-e control signaling or physical layer. The switch 1418 is controlled to be input to the 1408 or 1416 block depending on whether it is sent by signaling.

Receiver structure

15 illustrates a structure of a base station receiver according to the technique proposed by the present invention.

Referring to FIG. 15, the TPS reception controller 1500 controls the TPS information detector 1502. Accordingly, when the TPS information report start notification by the UE is applied as in the first embodiment, the switch 1504 causes the output of the EUDCH packet decoder 1506 to be input to the TPS information detector 1502 so that the MAC together with the BO can be used. -e Enable to detect the TPS information transmitted by control signaling.

When the initial TPS information is detected by the operation, the switch 1504 switches the output of the EU-DPCCH demodulator 1508 to be input to the TPS information detector 1502 and transmits the TPS transmitted through the EU-DPCCH in a T _TPS period. Allows you to detect information. On the other hand, the BO detector 1510 is a block for detecting the BO information transmitted through the MAC-e PDU, the BO information and the received EUDCH data amount is input to the UE EUDCH buffer status estimator 1512, Node B is the buffer The state is estimated. The TPS and UE buffer status information are input to block 1522 to generate scheduling allocation information to be transmitted to the UE.

In addition, when the implied TPS report start notification is applied as in the second embodiment, the UE buffer data amount 1514 estimated by the buffer state estimator 1512 is input to the TPS reception controller 1500 to enter the EUCDH packet data buffer. If the amount of data present is larger than the threshold for scheduling, periodic detection of the TPS information can be started. Similarly, when an implicit TPS report end notification is applied, detection of the TPS information is terminated when the buffer data amount 1514 is smaller than the threshold. On the other hand, when the end notification of TPS information reporting by the UE is applied, the end indicator detector 1516 detects the end indicator and informs the result to the TPS reception controller (1518) so that detection of the TPS information is no longer performed. .

In addition, when the TPS information report end instruction is performed by the base station as in the third embodiment, the TPS information report end indicator is generated in block 1520 based on the buffer data amount value estimated by the buffer state estimator 1512. Enable notification to the UE.

As described above, the present invention transmits only when transmission power state information is required in a mobile communication system supporting uplink packet service, thereby efficiently using limited radio resources by reducing unnecessary signaling overhead between the UE and the Node B. Has an effect.

1 is a diagram illustrating a general example of a mobile communication network supporting uplink packet service.

2 is a diagram illustrating a general signaling procedure performed between a user terminal and a base station to support uplink packet service.

3 is a diagram illustrating a structure of a MAC-e PDU for supporting uplink packet service according to an embodiment of the present invention.

4 is a diagram illustrating a transmitter structure of a user terminal supporting uplink packet service according to an embodiment of the present invention.

5 is a diagram illustrating a transmission timing of buffer status and transmission power status information according to a first embodiment of the present invention;

6 is a flowchart illustrating an operation procedure of a user terminal according to a first embodiment of the present invention.

7 is a flowchart illustrating an operation procedure of a base station according to the first embodiment of the present invention.

8 is a diagram illustrating a transmission timing of buffer status and transmission power status information according to a second embodiment of the present invention.

9 is a flowchart illustrating an operation procedure of a user terminal according to a second embodiment of the present disclosure.

10 is a flowchart illustrating an operation procedure of a base station according to the second embodiment of the present invention.

11 is a diagram illustrating a transmission timing of buffer status and transmission power status information according to a third embodiment of the present invention.

12 is a flowchart illustrating an operation procedure of a user terminal according to a third embodiment of the present invention.

13 is a flowchart illustrating an operation procedure of a base station according to the third embodiment of the present invention.

14 is a diagram illustrating a transmitter structure of a mobile terminal for applying embodiments of the present invention.

15 is a diagram illustrating a receiver structure of a base station for applying embodiments of the present invention.

Claims (7)

A method for efficiently transmitting packet data by a user terminal in a mobile communication system supporting uplink packet service, When the user terminal exceeds a preset value of the amount of data to be transmitted, transmitting a message including transmission power state information to a base station to notify the start of transmission of the uplink link data; Periodically notifying the uplink packet data by transmitting the message; If the amount of data is smaller than the preset value, transmitting a message including an indicator for terminating the transmission power state to the base station to notify the end of transmission of the uplink packet data. . The method of claim 1, And the user terminal transmits the message to a base station through control signaling. The method of claim 2, And the user terminal notifies the end of transmission of the uplink packet data to a base station through control signaling, including an indicator for terminating transmission of the transmission power state in a header of the message. The method of claim 2, The base station determines whether the reception error of the message and transmits an acknowledgment signal or a negative recognition signal to the user terminal. The method of claim 1, The user terminal further includes an indicator for terminating the transmission of the transmission power state in a dedicated control physical channel supporting an uplink packet service to notify the base station of the transmission of the uplink packet data. The method. An apparatus for efficiently transmitting packet data by a user terminal in a mobile communication system supporting uplink packet service, A packet data unit generator for generating a message including buffer status information or transmission power status information when a preset value of the amount of data to be transmitted is exceeded; And a transmission power state transmission controller for generating an indicator for periodically transmitting the transmission power state information and terminating transmission of the transmission power state information to control transmission of the uplink packet data. An apparatus for efficiently receiving packet data by a user terminal in a mobile communication system supporting uplink packet service, A transmit power state reception controller for controlling a detector to detect initial transmit power state information and periodically transmitted power state information from a decoded physical channel supporting an uplink packet service decoded from the received signal; And a detector for detecting initial transmission power state information from a message transmitted through control signaling under the control of the controller, and periodically detecting transmission power state information from a demodulated dedicated physical control channel.