KR20030068014A - A Method for transmitting, receiving and processing data in wireless mobile communication system - Google Patents

Abstract

PURPOSE: A method for transceiving and processing data in a wireless mobile communication system is provided to transmit original DCH(Dedicated Channel) data without performing a DTX(Discontinuous Transmission) for DPDCH(Dedicated Physical Data Channel) symbols when an HI(HS-DSCH(Downlink Shared Control Channel) Indicator) is not transmitted, thereby minimizing DCH data loss. CONSTITUTION: A UE(User Element) receives HI transmission symbols every HS-DSCH TTI(Transmission Time Interval)(101). The UE estimates a received HI signal, and selects P1 or one of P2, P3, and P4(102). The UE decodes an HS-SCCH(Shared Control Channel) indicated by the estimated HI signal(103). The UE decides whether a UE ID of the decoded HS-SCCH corresponds to a self HS-SCCH(104). If so, the UE decodes an HS-DCCH(Dedicated Control Channel)(106).

Description

A method for transmitting, receiving and processing data in wireless mobile communication system}

The present invention relates to a 3GPP UMTS system, and more particularly, to a transmission method of a HI (HS-DSCH Indicator) adapted to a system to which a high speed downlink packet access (HSDPA) technology is applied.

The HI is transmitted on the DPCH associated with the HS-DSCH, which serves as an indicator for informing the UE that data will be transmitted through the HS-DSCH.

Hereinafter, the prior art will be described.

First, a general background of the prior art and the present invention will be described.

UMTS (Universal Mobile Terrestrial System) is a third generation mobile communication system that evolved from the Global System for Mobile Communications (GSM) system, the second-generation European mobile communication standard.The GSM Core Network and Wideband Code Division Multiple Access (WCDMA) It aims to provide better mobile communication service based on access technology.

The first generation mobile communication refers to the analog method, the second generation mobile communication means the evolution to the digital method, and the third generation method is commonly called IMT-2000, and it means a breakthrough in communication capability.

For the international standardization of UMTS, in December 1998, national or national standards-setting bodies such as ETSI in Europe, ARIB / TTC in Japan, T1 in the United States, and TTA in Korea were established by the Third Generation Mobile Standardization Group. The Partnership Project (hereinafter abbreviated as 3GPP) is formed, and through this 3GPP, detailed specification of UMTS, a European IMT-2000 system, is defined.

In 3GPP, UMTS standardization work is divided into 5 Technical Specification Groups (hereinafter abbreviated as TSG) in consideration of the independence of network components and their operation for rapid and efficient technology development of UMTS. I'm going.

Each TSG is responsible for the development, approval, and management of standards within the relevant areas, among which the Radio Access Network (hereinafter referred to as RAN) group (TSG-RAN) is a WCDMA access technology (asynchronous) in UMTS. Develop specifications for the functions, requirements, and interfaces of the UMTS Terrestrial Radio Access Network (hereinafter referred to as UTRAN), a new radio access network to support CDMA).

The TSG-RAN Group is again composed of a Plenary Group and four Working Groups. Working Group 1 (WG1) develops standards for the Physical Layer (WG1), while the second Working Group (WG2) works with the Data Link Layer (2nd Layer) and Network Layer (WG2). Role of the third tier).

In addition, the third operation group defines standards for interfaces between base stations, radio network controllers (hereinafter referred to as RNCs), and core networks in the UTRAN, and the fourth operation group relates to radio link performance. Discuss requirements and requirements for radio resource management.

1 is a diagram showing the structure of the UTRAN of the 3GPP system to which the conventional and the present invention is applied.

Referring to FIG. 1, the UTRAN 110 includes one or more Radio Network Sub-systems (hereinafter referred to as RNS) 120 and 130, and each RNS 120 and 130 is connected to one RNC 121 and 131. It consists of one or more base stations (Node Bs) 122, 123, 132, 133 managed by the RNCs 121, 131. The RNCs 121 and 131 are connected to a mobile switching center (MSC) 141 for circuit-switched communication with a GSM network, and SGSN (for packet-switched communication with a general packet radio service (GPRS) network). Serving GPRS Support Node) 142.

The base station (Node B) 122, 123, 132, 133 is managed by the RNC (121, 131), and receives the information sent from the physical layer of the terminal 150 in the uplink, and the terminal 150 in the downlink It serves as an access point of the UTRAN to the terminal transmitting to. The RNCs 121 and 131 are in charge of allocating and managing radio resources. The RNC, which is responsible for the direct management of the base station Node B, is called a control RNC (CRNC), and is in charge of managing a common radio resource.

A place that manages dedicated radio resources allocated to each terminal is called a serving RNC (SRNC).

The control RNC and the responsible RNC may be the same, but when the terminal moves out of the area of the responsible RNC to the area of another RNC, the control RNC and the responsible RNC may be different.

The various components in the UMTS network can be in different locations, so an interface is needed to connect them. The base station Node B and the RNC are connected by an Iub interface, and the RNC is connected through an Iur interface. The interface between the RNC and the core network is called Iu.

2 illustrates a structure of an interface protocol of a 3GPP radio access network standard for wirelessly connecting a terminal and a network through the air.

Referring to FIG. 2, the radio access interface protocol consists of a physical layer (PHY), a data link layer, and a network layer horizontally, and vertically includes a control plane and data information for transmitting control signals. It is divided into user planes for transmission.

Here, the user plane is an area in which traffic information of the user is transmitted, such as voice or IP packet transmission, and the control plane is an area in which control information is transmitted, such as interface or network maintenance and management of a network.

The protocol layers of FIG. 2 are based on the lower three layers of the seven layers of the Open System Interface (OSI) reference model, which are well known in communication systems, and include the first layer L1, the second layer L2, It may be divided into a third layer (L3).

The first layer L1 serves as a physical layer (PHY) for the air interface, and a transport channel with a medium access control layer (hereinafter referred to as MAC) layer on the upper layer. It is connected through the channels and transmits the data delivered to the physical layer through the transport channel to the receiver using various coding and modulation methods suitable for the wireless environment.

The transport channel existing between the physical layer (PHY) and the MAC layer is a dedicated transport channel and a common transport, respectively, depending on whether the terminal can be used exclusively or shared by multiple terminals. It is divided into channels (Common Transport Channel).

The second layer L2 serves as a data link layer, and allows multiple terminals to share radio resources of the WCDMA network. The second layer (L2) is the MAC layer, Radio Link Control (hereinafter referred to as RLC) layer, Packet Data Convergence Protocol (hereinafter referred to as PDCP) layer, and broadcast / multicast control (Broadcast / Multicast Control; hereinafter abbreviated as BMC) is divided into layers.

The MAC layer transfers data through an appropriate mapping relationship between logical channels and transport channels. Logical channels are provided with various logical channels according to the type of information transmitted to the channels connecting the upper layer and the MAC layer.

In general, a control channel is used to transmit control plane information, and a traffic channel is used to transmit information of the user plane.

The RLC layer configures an appropriate RLC PDU suitable for transmission by a segmentation and concatenation function of an RLC SDU transmitted from an upper layer, and performs an automatic repeat request for retransmitting the lost RLC PDU during transmission; ARQ) function can be performed.

The RLC SDU or RLC descended from the upper layer operates in three ways: transparent mode, unacknowledged mode, and acknowledgment mode, depending on the method of processing the RLC SDU from the upper layer. There is an RLC buffer for storing PDUs.

The PDCP layer is located on top of the RLC layer and makes data transmitted through a network protocol such as IPv4 or IPv6 suitable for transmission in the RLC layer. In particular, a header compression technique that compresses and transmits header information of a packet may be used for efficient transmission of an IP packet.

The BMC layer enables a message transmitted from a cell broadcast center (CBS) to be transmitted through an air interface. The main function of the BMC is to schedule and transmit a cell broadcast message transmitted to a terminal, and generally transmits data through an RLC layer operating in an unresponsive mode.

For reference, since the PDCP layer and the BMC layer transmit only user data, they are located only in the user plane. Unlike these, the RLC layer may belong to the user plane or to the control plane depending on the layer connected to the upper layer. In the case of belonging to the control plane corresponds to the case of receiving data from the radio resource control (hereinafter referred to as RRC) layer, otherwise it corresponds to the user plane.

In general, a transmission service of user data provided to a higher layer by a second layer L2 in a user plane is defined as a radio bearer (RB), and is defined as a higher layer by a second layer L2 in a control plane. The transmission service of the control information provided by is defined as a signaling radio bearer (SRB).

In addition, as shown in FIG. 2, in the case of the RLC layer and the PDCP layer, several entities may exist in one layer. This is because one terminal has several radio carriers, and generally only one RLC entity and PDCP entity are used for one radio carrier. Entities of the RLC layer and the PDCP layer may perform independent functions in each layer.

The RRC layer located at the bottom of the third layer L3 is defined only in the control plane, and is responsible for control of transport channels and physical channels in connection with setting, resetting, and releasing radio carriers. In this case, the radio carrier setup (RB setup) refers to a process of defining characteristics of a protocol layer and a channel necessary for providing a specific service and setting each specific parameter and operation method.

The WCDMA system described above aims at a transmission rate of 2Mbps in a indoor and pico-cell environment and 384kbps in a general wireless environment. However, as the wireless Internet is becoming more common and the number of subscribers is increasing, more various services are emerging, and higher speeds are required to support them. Therefore, 3GPP is currently evolving the WCDMA network to provide a high speed transmission rate, and one of the representative systems is High Speed Downlink Packet Access (hereinafter abbreviated as HSDPA). have.

Based on WCDMA, the HSDPA system can support speeds of up to 10Mbps in downlink, and can provide shorter latency and improved capacity. The techniques employed in the HSDPA system to provide improved transmission rates and capacities include Link Adaptation (LA), Hybrid Automatic Repeat Request (HARQ), and fast cell selection. Fast Cell Selection (hereinafter referred to as FCS), and Multiple Input Multiple Output (hereinafter referred to as MIMO) antenna techniques.

The link adaptation technique (LA) uses a modulation and coding scheme (abbreviated as MCS) according to the state of the channel. If the channel state is good, a high modulation such as 16QAM and 64QAM is used. In case the channel condition is not good, a low modulation method such as QPSK is used.

In general, the low-modulation method has a smaller amount of transmission than the high-modulation method, but it shows excellent transmission success rate when the channel environment is not good. Therefore, it may be considered to be advantageous when the influence of fading or interference is large. .

On the contrary, the high modulation methods have a much higher frequency utilization efficiency than the low modulation methods, and can provide a transmission rate of 10 Mbps using the 5 MHz bandwidth of the WCDMA. However, it is very sensitive to the effects of noise and interference.

Therefore, when the terminal is located close to the base station, it is possible to increase the transmission efficiency by using 16QAM or 64QAM, and when the terminal is located at the cell boundary or the influence of fading is low, a low modulation method such as QPSK is useful. Do.

The HARQ method is a retransmission method having a different concept from that of a packet retransmission performed in the RLC layer. This ensures higher decoding success rates by combining data used and retransmitted in conjunction with the physical layer with previously received data. In other words, it is a method of decoding by combining the retransmitted packet with the previous step of decoding while storing the packet which failed to be transmitted without discarding it. Therefore, when used together with the LA technique, the packet transmission efficiency can be greatly increased.

The FCS method is similar to the conventional soft handover. Although the terminal may receive data from multiple cells, the terminal may receive data from a cell having the best channel state in consideration of the channel state of each cell. Conventional soft handover is a method of receiving data from multiple cells and increasing the transmission success rate using diversity, but the FCS method receives data from only one specific cell in order to reduce interference between cells.

MIMO antenna technique is a method that can improve the data transmission speed by using several independent channels in a channel environment where scattering is high. It is a system that is composed of several transmitting antennas and several receiving antennas to obtain diversity gain by reducing the correlation between radio waves received for each antenna.

Meanwhile, the HSDPA system is based on the existing WCDMA network and tries to introduce a new technology while keeping the WCDMA network as it is. However, some modifications are inevitable to incorporate new technologies.

Representatively, the example is an improvement of the existing base station (Node B) function. That is, in the WCDMA network, most of the control functions are located in the RNC, but most of the new technologies for the HSDPA system are managed by the base station (Node B) in order to adapt to the channel situation more quickly and reduce the delay time to the RNC.

However, the extended function of the base station (Node B) is not a function of replacing the RNC, and from the standpoint of the RNC, it can be seen that the functions for the high speed data transmission are in charge of the auxiliary function added.

Therefore, unlike the existing WCDMA system, the base station Node B has been modified to perform a part of the MAC function, and a layer for performing this is called a MAC-hs sublayer.

The MAC-hs sublayer may be located above the physical layer to perform packet scheduling or HARQ and LA functions. In addition, a transport channel called HS-DSCH (HSDPA Downlink Shared Channel), which is different from the existing transport channel, is used for data transmission for HSDPA.

The HS-DSCH has a short transmission time interval (TTI) (3 slots, 2 ms), unlike the DSCH defined in the conventional WCDMA system standard R'99 / R'4, and has a high data rate. It supports various modulation code set (MCS) that can be used.

Optimum performance can be obtained by selecting the best MCS for the channel situation.

To this end, hybrid ARQ (HARQ) technology, which combines automatic repeat request (ARQ) technology and channel coding technology, ensures reliable transmission and uses code division multiplexing (CDM). It is proposed to support up to four users at the same time. The physical channel corresponding to the transport channel HS-DSCH is the same as before.

As described above, control information is required for HS-DSCH, and the information is transmitted through a shared control channel (HS-SCCH) introduced in the HSDPA standard.

For reference, Release 1 and Release 2 are the standard versions for Global System for Mobile Communication (GSM) respectively, and R'99 is the abbreviation of Release 1999, referring to the standard version of 3GPP. , Same as Release 3).

R4 refers to the standard version of 3GPP and is an acronym for Release 4 (released in March 2001, same as Release 2000).

Release 5 is also the version that is currently being standardized.

The physical channel corresponding to the transport channel HS-DSCH is described below.

The 3GPP system supports high speed packet data service in downlink with HS-DSCH transmission.

To this end, a new structure of a transport channel called HS-DSCH and control signaling for it have been proposed. 5 illustrates a structure of a physical channel HS-PDSCH to which an HS-DSCH is mapped.

The HS-PDSCH is transmitted in one or multiple SF = 16 codes. The HS-DSCH subframe consists of three slots. HS-PDSCH is modulated with QPSK or 16 QAM.

3 is a subframe structure for the HS-PDSCH.

As described above, transmission of control information for the HS-DSCH is required. This information is transmitted through the physical channel shared control channel (HS-SCCH).

Control information can be largely divided into transport format and resource related information (TFRI) and HARQ-related information.

The TFRI includes information on the HS-DSCH transport channel set size, modulation method, coding rate, and number of multicodes. HARQ-related information includes information such as block number and redundancy version. In addition, information about UE identification (UE Id) is transmitted to indicate which user's information. UE Id-related information performs a CRC operation together with TFRI and HARQ information to transmit only the resulting CRC.

The subframe structure of the downlink shared control channel for transmitting downlink control information is shown in FIG.

Transmission configuration of the HS-SCCH for one UE is shown in FIG. The number of configurable HS-SCCHs in one UE is M = 4.

6 shows downlink shared control channel and timing of HS-DSCH.

In FIG. 6, HI is transmitted through a DPCH associated with the HS-DSCH, which serves as an indicator for informing that a UE will transmit data through the HS-DSCH.

That is, when the HI bit is set, the UE can read control information transmitted through the shared control channel and recover the HS-DSCH data. The time offset (t _HS-DSCH-HI ) between the DL DPCH slot transmitting the HI and the start of the HS-SCCH is set so that the beginning of the HI and the first slot of the HS-SCCH overlap.

HI is generated in the Node B to which the cell transmitting the corresponding HS-DSCH belongs. The transmission of HI is transmitted through the downlink associated DPCH only when the number of HS-SCCHs allocated to a UE is two or more. At this time, HI informs the HS-SCCH that the UE decodes at the characteristic moment.

If there is HS-DSCH data to be received by the UE, HI is transmitted every third slot of the associated DPDCH corresponding to the HS-DSCH TTI. DCHs not related to HSDPA are mapped to DPDCH, and user data (voice, video data, etc.) or higher signaling information transmitted are transmitted.

HI is transmitted by puncturing one symbol (2 bits) transmitted on the DPDCH. If there is no HS-DSCH data to be received by the UE, HI transmits one symbol of the corresponding DPDCH to DTX (Discontinous Transmission).

7 shows a coding scheme of HI. If HI is P0, it corresponds to DTX (Discontinous Transmission), indicating that there is no data transmission at that moment. When HI is transmitted to one of P1, P2, P3, and P4, it informs which channel should be decoded among four HS-SCCHs mapped to each.

However, although the HI is not always transmitted in the related art, since data symbols transmitted on the associated DPDCH are puncturized every three slots for HI transmission, data transmitted on the associated DPDCH is lost.

This is because the UE detects the DTX of HI. That is, since the UE needs to know whether there is data to be received by the DTX (P0) of the HI, even if the HI is not transmitted, the symbol position promised to be transmitted by the HI should always be DTX.

Therefore, in order to solve the above problems, the present invention proposes a transmission scheme of HI. In the conventional scheme, since the UE performs DTX detection, the corresponding DPDCH symbol is DTX even though HI is not transmitted. If HI is not transmitted due to no operation, the original DCH data can be transmitted without DTXting the corresponding DPDCH symbol.

In this case, the DPDCH symbol that is promised to transmit HI in every 3 slots is defined as 'HI transmission symbol'.

1 is a view showing the structure of the UTRAN of the 3GPP system to which the prior art and the present invention is applied

2 is a structure of an interface protocol of a 3GPP radio access network standard for wirelessly connecting a terminal and a network through the air

3 shows a subframe structure for the HS-PDSCH

4 shows a subframe structure of a downlink shared control channel for transmitting downlink control information

5 is a transmission configuration of HS-SCCH for one UE

6 is a diagram illustrating timing of a downlink shared control channel and an HS-DSCH.

7 is a diagram illustrating a coding method of HI

8 is a flowchart illustrating HI transmission in Node B, a transmitting end.

9 is a flowchart for explaining an example of the HI and DPDCH reception scheme of the UE.

10 is a flowchart for explaining another example of the HI and DPDCH reception scheme of the UE;

In the wireless mobile communication system according to the present invention for achieving the above object, the present invention provides a method for processing data transmitted from a receiving end,

Receiving user data transmitted through a dedicated channel; Demodulating and storing all symbols of the transmitted data; decoding symbols transmitted on all dedicated channels including HI transmission symbols regardless of whether HI is actually transmitted.

The objects and features according to the present invention will become apparent from the following detailed description of the embodiments with reference to the accompanying drawings.

First, HI transmission is described in a transmitting node Node B.

As shown in FIG. 8, if there is HS-DSCH data to transmit, HI is transmitted to the corresponding UE. At this time, Node B puncturing a symbol of the data field of the promised DPCH, and then carries one of P1 or P2, P3, and P4 of HI to transmit.

However, if there is no HS-DSCH data to transmit, HI is not transmitted to the corresponding UE.

At this time, Node B transmits the data field of DPCH without puncturing.

That is, the HI transmission symbols, which were DTX in the conventional method, are not DTX, but the original DCH data is transmitted in place of the HI transmission symbol.

On the other hand, the reception process of the UE is largely divided into process 1 and process 2.

Process 1 is an HSDPA process of decoding HI and decoding up to HS-DSCH.

On the other hand, process 2 is the associated DPDCH decoding process. Both processes are performed in parallel, while process 1 is performed five times while process 2 is performed once.

The associated DPDCH is generally 15 slots, and the HS-SCCH consists of 3 slots as shown in FIG.

Therefore, the above description is one example of the case where the TTI is 10ms.

Hereinafter, HI and DPDCH reception methods and processing methods of a UE, which is a receiver, will be described.

9 illustrates an example of the HI and DPDCH reception scheme of the UE.

First, Process 1 described above will be described.

The UE receives the HI transmit symbol of the DPDCH every HS-DSCH TTI (3 slots) (step 91).

The UE assumes that HI is always transmitted, and estimates the received HI signal to select P1 or one of P2, P3, and P4.

The UE decodes the HS-SCCH indicated by the estimated HI signal. The UE ID of the decoded HS-SCCH is determined to determine whether the corresponding HS-SCCH is really correct.

If the decoded HS-SCCH is determined to be its own, the UE receives the corresponding HS-DSCH using the information of the HS-SCCH. (Step 92,93,94,95,96).

The above process 2 will be described.

The UE receives the DCH user data sent on the DPDCH. At this time, the UE demodulates all DPDCH symbols including HI transmission symbols and stores them in the buffer.

Regardless of whether HI is actually transmitted, all DPDCH symbols, including HI transmission symbols, are always decoded. (Step 97,98).

10 is a flowchart illustrating another example of the HI and DPDCH reception scheme of the UE.

First, Process 1 described above will be described as steps 101 to 106.

The UE receives HI transmit symbols every HS-DSCH TTI (3 slots). The UE assumes that HI is always transmitted, and estimates the received HI signal to select P1 or one of P2, P3, and P4.

The UE decodes the HS-SCCH indicated by the estimated HI signal. The UE ID of the decoded HS-SCCH is determined to determine whether the corresponding HS-SCCH is really correct.

If it is determined that the decoded HS-SCCH is not its own, it transfers the discrimination information to step 109 and returns to step 102. If the decoded HS-SCCH is determined to be its own, step 106 is performed.

In step 105, the UE receives the corresponding HS-DSCH using the information of the HS-SCCH.

The above process 2 will be described.

The UE receives the DCH user data sent on the DPDCH. At this time, the UE demodulates all DPDCH symbols including HI transmission symbols and stores them in the buffer.

If it is determined that the decoded HS-SCCH is not its own, it is determined that the actual HI is not transmitted, and the UE recovers the DCH data after including the HI transmission symbols in the DPDCH decoding.

Otherwise, the UE decodes only the remaining symbols except HI transmit symbols. For example, when decoding a DPDCH of 10 ms, there are five HI transmission symbols. If three HI transmission symbols are determined that HI is not actually transmitted, the three HI transmission symbols are decoded when DPDCH decoding. Include.

Here, HI transmission symbols that have not undergone the discrimination process, that is, no discrimination result are also not decoded (steps 107, 108, 109).

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments.

Therefore, the above description is not limited to the scope of the invention defined by the limitations of the claims.

As described above, the DPDCH symbol is DTX even though HI is not transmitted because the UE performs DTX detection. However, in the present invention, when the HI is not transmitted because the UE does not perform DTX detection, the DPDCH symbol is not transmitted. This allows the original DCH data to be transmitted without DTX. Therefore, DCH data loss is minimized.

Claims (9)

In transmitting information (HI) informing the data to be transmitted from the transmitting end to the receiving end, Determining whether there is data to be transmitted at the transmitting end; If there is no data to be transmitted, transmitting the data without transmitting the HI without discontinuous transmission (DTX) when there is no data to be transmitted. The method of claim 1, wherein the determination of whether there is data to be transmitted by the transmitter determines whether there is data to be transmitted through the HS-DSCH. The data transmission / reception method of claim 1 or 2, wherein the DCH data is transmitted in a non-transmitted HI transmission symbol when there is no data to be transmitted. In processing the data transmitted from the receiving end, Receiving user data transmitted through a dedicated channel; Demodulating and storing all symbols of the transmitted data; Decoding the symbols transmitted through all dedicated channels including HI transmission symbols regardless of whether HI is actually transmitted; and receiving and processing data in a wireless mobile communication system. In processing the data transmitted from the receiving end, Receiving user data transmitted through a dedicated channel; Demodulating and storing all symbols of the transmitted data; Determining whether the user information of the decoded HS-SCCH is mapped to the received HI signal and is own; Decoding HI transmission symbols together with data transmitted through a dedicated channel when it is determined that HI is not actually transmitted; Data receiving and processing method in a wireless mobile communication system comprising a. 6. The method of claim 5, wherein it is determined whether the user information of the decoded HS-SCCH mapped to the received HI signal is its own. A method for receiving and processing data in a wireless mobile communication system, characterized by decoding. The data receiving and processing method according to claim 5 or 6, wherein whether or not HI is actually transmitted is determined through user information (ID) transmitted on the HS-SCCH. 6. A method according to claim 4 or 5, wherein the dedicated channel is a DPDCH. 6. The method of claim 5, wherein the HI transmission symbol in the absence of a result of the HI discrimination process performed during the associated DPDCH decoding process is included in the decoding.