KR20030025765A - Apparatus for transferring high speed-downlink shared channel indicator to maintain compatibility in communication system using high speed downlink packet access scheme and method thereof - Google Patents

Abstract

PURPOSE: A device for transmitting an HS-DSC(High Speed-Downlink Shared Channel) indicator considering compatibility in a communication system using an HSDPA(High Speed Downlink Packet Access) method is provided to suggest a dedicated physical channel structure, and to adaptively control a field for transmitting the HS-DSC indicator, thereby improving system performance and efficiency. CONSTITUTION: A user terminal supports an HSDPA service. A controller determines a field for transmitting an HS-DSC indicator showing that HSDPA service data exists, among fields of a dedicated physical channel slot of a communication system that does not use the HSDPA service in order to maintain compatibility between user terminals that do not support the HSDPA service. A dedicated physical channel transmitter inserts the HS-DSC indicator into the determined field under the control of the controller, multiplexes the indicator with the rest fields of the dedicated physical channel, and transmits the multiplexed indicator.

Description

Apparatus and method for transmitting high speed forward common channel indicators considering compatibility in a communication system using a high speed forward packet access method AND METHOD THEREOF}

The present invention relates to an apparatus and method for transmitting a forward dedicated physical channel for supporting high speed downlink packet access (HSDPA) in a code division multiple access communication system, and in particular, a base station and a terminal that do not support HSDPA service. The present invention relates to a transmission apparatus and a method of a forward dedicated physical channel for maintaining compatibility between a base station and a terminal supporting the HSDPA service.

In general, High Speed Downlink Packet Access (HSDPA) is a high-speed forward common, which is a forward data channel for supporting forward high-speed packet data transmission in a Universal Mobile Terrestrial System (UMTS) communication system. A data transmission method including a channel (High Speed Downlink Shared Channel (HS-DSCH)) and control channels related thereto is generically referred to. In order to support the HSDPA, an adaptive modulation and coding scheme (hereinafter referred to as "AMC"), a hybrid automatic retransmission request (hereinafter referred to as "HARQ"), and fast cell selection (fast cell) Select: (hereinafter referred to as "FCS") has been proposed.

First, the AMC method will be described.

The AMC scheme is a modulation scheme of different data channels depending on a channel state between a specific base station (Node B, hereinafter referred to as "Node B") and a terminal (UE: User Element, hereinafter referred to as "UE"). And a data transmission method for determining the coding method and improving the use efficiency of the entire base station. Accordingly, the AMC scheme has a plurality of modulation schemes and a plurality of coding schemes, and modulates and codes a data channel signal by combining the modulation schemes and coding schemes. Typically, each of the combinations of modulation schemes and coding schemes is referred to as a modulation and coding scheme (hereinafter, referred to as "MCS"), and level n to level n depending on the number of MCSs. Up to several MCSs can be defined. That is, the AMC scheme is a scheme for adaptively determining the level of the MCS according to a channel state between the UE and a Node B which is currently wirelessly connected, thereby improving overall Node B overall system efficiency.

Secondly, an HARQ scheme, in particular, a multi-channel Stop And Wait Hybrid Automatic Retransmission Request (hereinafter referred to as "n-channel SAW HARQ") will be described.

The HARQ scheme newly applies the following two methods to increase the transmission efficiency of the ARQ (Automatic Retransmission Request) scheme. The first scheme is to perform the retransmission request and response between the UE and the Node B. The second scheme is to temporarily store the data in error and combine it with the retransmission data of the corresponding data. will be. In addition, the HSDPA scheme has introduced the n-channel SAW HARQ scheme to compensate for the shortcomings of the conventional Stop and Wait ARQ (SAW ARQ) scheme. In the SAW ARQ scheme, the next packet data is transmitted only after receiving an ACK for the previous packet data. However, since the next packet data is transmitted only after receiving the ACK for the previous packet data, there may occur a case where the ACK should be waited even though the packet data may be transmitted at present. In the n-channel SAW HARQ scheme, a plurality of packet data may be continuously transmitted without receiving an ACK for the previous packet data, thereby improving channel usage efficiency. That is, if n logical channels are established between the terminal and the base station, and each of the n channels can be identified by a specific time or channel number, the UE that receives the packet data is received at any time. It is possible to know which packet data is transmitted through which channel, and may take necessary measures such as reconstructing the packet data in the order in which it is to be received or soft combining the packet data.

Finally, the FCS method will be described.

The FCS scheme is a method of quickly selecting a cell having a good channel state among a plurality of cells when the terminal using the HSDPA scheme is located in a cell overlap region, that is, a soft handover region. Specifically, the FCS scheme includes: (1) when a terminal using the HSDPA enters a cell overlap region of an old base station and a new base station, the terminal is configured to have a radio link with a plurality of cells, that is, a plurality of base stations. Radio Link ".) Is set. In this case, a set of cells in which a radio link is established with the terminal is called an active set. (2) Receive packet data for HSDPA only from cells that maintain the best channel state among the cells included in the active set to reduce the overall interference. Herein, a cell transmitting HSDPA packet data because the channel state is the best in the active set is called a best cell, and the terminal periodically checks the channel state of the cells belonging to the active set and compares it with the current best cell. When a cell having a better channel state occurs, a best cell indicator or the like is transmitted to cells belonging to the active set to change the current best cell into a cell having a better channel state. Includes an identifier of a cell selected as a best cell, and the cells in the active set receive the best cell indicator and examine a cell identifier included in the best cell indicator. Thus, each of the cells in the active set checks whether the best cell indicator corresponds to its best cell indicator, and the corresponding cell selected as the best cell is a packet to the terminal using a fast forward common channel (HS-DSCH). Send the data.

1 is a diagram schematically illustrating a forward channel structure of a communication system using a conventional high speed forward packet access scheme.

Referring to FIG. 1, a downlink dedicated physical channel (DPCH) is referred to as a conventional code division multiple access communication system, for example, a field defined in Release-99. ) And a fast forward common channel indicator (HI: HS-DSCH Indicator, hereinafter referred to as "HI") indicating whether there is HSDPA packet data to be received by the terminal. The HI transmitted through not only indicates whether there is HSDPA packet data to be received by the corresponding terminal, and when the HSDPA packet data is present, common to receive control information on the HS-DSCH where the HSDPA packet data is actually transmitted. The channelization code of the control channel (SHCCH) may be informed, and some of the HS-DSCH control information may be used, if necessary. For example, control information such as MCS level may be transmitted through the HI .. Typically, the HS-DSCH channel indicates which SHCCH channel the UE should receive.

For example, when the HSDPA packet data is transmitted in units of N (= N1 + N2) slots (ie, HSDPA transmission time interval (TTI = N slots)), the slot structure does not change in the TTI. If it is fixed, the HI is divided into N1 slots and transmitted, and the part transmitting HI in the remaining N2 slots is treated as discontinuous transmission (DTX). If the slot structure is variable in the TTI, only N1 slots that transmit HI may have a slot structure with an HI field, and the remaining N2 slots may have a slot structure defined in the existing Release-99. For example, FIG. 1 illustrates a case in which N1 is 1 because HI is transmitted only through one slot. In the present invention, the slot through which HI is transmitted in the TTI is not fixed to the first slot as shown in FIG. The criterion for determining the slot to transmit the HI at the base station side is the SHCCH channel TTI starting point. HI is transmitted to the first DPCH slot on the basis of the TTI starting point of the SHCCH. For example, in FIG. 1, since the TTI starting point of the SHCCH is the same as the slot starting point of the DPCH channel, HI may be transmitted to the first slot of the DPCH. If the start point of the first slot of the DPCH is slightly ahead of the start point of the SHCCH TTI, then the first DPCH slot after the start of the SHCCH TTI will be the second slot in the TTI of the DPCH, and HI will be transmitted to the second slot of the DPCH. MCS level, HS-DSCH channelization code, HARQ process number, HARQ packet number, etc., which are information for controlling the DSCH channel (hereinafter referred to as HS-DSCH control information), indicate the shared control channel (hereinafter referred to as SHCCH). Send to the terminal through. Here, the HS-DSCH control information will be described.

(1) MCS level: Informs the modulation and channel coding method to be used in the HS-DSCH channel.

(2) HS-DSCH channelization code: channelization code used for a specific terminal in the HS-DSCH channel

(3) HARQ process number: n-channel SAW When HARQ is used, it informs a channel to which a specific packet belongs among logical channels for HARQ.

(4) HARQ packet number: When the best cell is changed in the FCS, the terminal informs the terminal of the number of forward packet data so that the terminal can inform the newly selected best cell of the transmission state of the HSDPA data.

One or more channelization codes may be allocated to the SHCCH. In FIG. 1, up to four SHCCHs can be allocated to each of the UEs. Therefore, the HI of the DPCH informs the SHCCH channel of the UE to be received along with the presence or absence of the HSDPA data packet to be received. Since the number of SHCCHs can be allocated up to four, two bits (2 bits) of HI can inform the information on the SHCCH to be received by the UE. The two HI bits are information bits and may be encoded and transmitted as NHI bits when transmitted on the actual DPCH channel. For example, if HI is 00, the UE receives SHCCH # 1, 01 receives SHCCH # 2, 10 receives SHCCH # 3, and 11 receives SHCCH # 4. The HS-DSCH is a channel through which HSDPA packet data transmitted from the base station to the terminal is transmitted.

Next, a process of receiving the HSDPA service by the UE using three channels as described above, that is, DPCH, SHCCH, and HS-DSCH will be described.

First, the UE demodulates a bit transmitted to the HI field by receiving the SHCCH channel together with the forward DPCH signal. The UE will receive both DPCH and SHCCH and the UE will have to demodulate all SHCCHs until it extracts the HI information bits indicating which SHCCH channel the UE should read. Since the UE knows the TTI start point and the DPCH slot start point of the SHCCH channel, it can know which slot of the DPCH is transmitted. Therefore, the UE can demodulate the HI even in the case of the variable DPCH slot structure described above. If the HI field of the slot in which the HI is transmitted is DTX, the UE recognizes that there is no HSDPA packet data to be received and waits until the next TTI while receiving only DPCH. On the other hand, when a specific bit value is transmitted to the HI, the UE recognizes that HSDPA packet data exists and decodes only the corresponding SHCCH signal according to the HI information bit value and discards the signals of the remaining SHCCH channels. Then, the corresponding SHCCH signal is read to extract the MCS level, channelization code, and HARQ-related control information of the HS-DSCH necessary for demodulating the HS-DSCH channel. Finally, the UE detects HSDPA packet data by receiving and demodulating an HS-DSCH signal using control information detected through the SHCCH.

As described above, in order to demodulate the HS-DSCH signal, the UE must read the SHCCH signal to detect the corresponding control information. That is, as shown in FIG. 1, the UE first receives DPCH and SHCCH signals, reads control information, and then receives an HS-DSCH channel. Eventually, the forward DPCH and SHCCH start time is earlier than the start time of HS-DSCH, which is determined whether the other two channels are data corresponding to the UE before the UE reads the HS-DSCH indicator and detects the corresponding information. Because it can not be. That is, since the data corresponding to the UE cannot be known before the HS-DSCH indicator is read, the data must be temporarily stored in a buffer, so that the time for reading the HS-DSCH indicator is allowed, Receiving a channel to relieve the UE buffer burden. As a result, the UE reads the HS-DSCH indicator portion of the forward DPCH to check whether there is HSDPA packet data to be received by the UE itself, and if the HSDPA packet data to be received by the UE itself is found, the UE After reading information for controlling the HS-DSCH channel of the SHCCH, the HSDPA packet data is received through the HS-DSCH channel according to the control information.

In FIG. 1, a dedicated physical channel structure of a communication system using a fast forward packet access method has been described. Next, a dedicated physical channel structure of a communication system not using the fast forward packet access method will be described with reference to FIG. Shall be.

2 is a diagram illustrating a dedicated physical channel structure of a conventional code division multiple access communication system.

Referring to FIG. 2, first, the DPCH includes a structure of a code division multiple access communication system that does not support the existing HSDPA service, for example, a forward dedicated physical channel defined in Release-99. Same as The Data1 and Data2 fields transmit data for supporting dedicated services such as voice or data for supporting higher layer operations. A Transfer Power Control (TPC) field transmits a downlink transmit power control command for controlling uplink transmit power, and a Transfer Format Combination Indicator (TFCI) field indicates the Data1. And transport format combination information of the Data2 field. The pilot field is a field for transmitting a predetermined pilot symbol sequence in the system, which is used by the terminal to estimate the forward channel state. Here, Data1 and Data2 are forward dedicated physical data channels (DPDCH) (hereinafter referred to as DPDCH), and TPC, TFCI, and Pilot are forward dedicated physical control channels (DPCCH). DPCCH ". NData1, NTPC, NTFCI, NData2, and NPilot shown in FIG. 2 mean the number of bits transmitted in each field, and the DPCH structure shown in FIG. 2 divides the TFCI field in the 3GPP R-99 standard. A portion thereof is used to transmit a TFCI for a forward dedicated physical data channel (DPDCH), and the other portion transmits a TFCI for a downlink shared channel (DSCH). It defines the method to use.

However, since the DPCH structure used in Release-99 described with reference to FIG. 2 cannot transmit information that Node B should transmit to the UE for the HSDPA service, the HSDPA service is supported while supporting the Release-99 service. To support this, a new forward DPCH structure is needed. Meanwhile, the UE supporting the HSDPA may receive a data packet through the HS-DSCH from the Node B serving the HSDPA and at the same time, receive the data through the forward DPCH from the Node B not supporting the HSDPA. Therefore, the need for forward DPCH for HSDPA needs to be able to support not only the HSDPA service but also a code division multiple access communication system that does not support the existing HSDPA service, that is, a service supported by Release-99.

Accordingly, an object of the present invention is to provide an apparatus and method for transmitting a dedicated physical channel signal that maintains compatibility between a communication system using a fast forward packet access method and a communication system not using the fast forward packet access method.

Another object of the present invention is to adaptively set a field for transmitting a fast forward common channel indicator indicating that the fast forward packet access service data exists in a communication system using a fast forward packet access scheme according to a spreading rate of a dedicated physical channel. To provide an apparatus and method.

It is another object of the present invention to provide information data originally transmitted in a field in which a fast forward common channel indicator indicating that the fast forward packet access service data is present in a communication system using a fast forward packet access scheme, the fast forward common channel. An apparatus and method for transmitting the same field through the same field in a slot other than the slot in which the indicator is transmitted.

The apparatus of the present invention for achieving the above objects; A system that does not support a high speed forward packet access service transmits user data field for transmitting user data, a transmit power control field for transmitting a command for controlling reverse transmission power, and transmit format combination indication information of the user data. It has a dedicated physical channel structure multiplexed with a transport format combination indication field and a pilot field for transmitting a pilot symbol string, and is used for transmitting a fast forward common channel indicator while maintaining compatibility with a system that does not serve the fast forward packet access scheme. An apparatus, comprising: a dedicated physical channel of a communication system that does not use the fast forward packet access service to maintain compatibility between a user terminal that supports the fast forward packet access service and a user terminal that does not support the fast forward packet access service.A controller for determining a field to transmit a fast forward common channel indicator indicating that the fast forward packet access service data exists among slot fields; and inserting the fast forward common channel indicator into the determined field according to the control of the controller to insert the fast forward common channel indicator. And a dedicated physical channel transmitter for multiplexing and transmitting the remaining fields of the dedicated physical channel.

The method of the present invention for achieving the above object; A system that does not support a high speed forward packet access service transmits user data field for transmitting user data, a transmit power control field for transmitting a command for controlling reverse transmission power, and transmit format combination indication information of the user data. It has a dedicated physical channel structure multiplexed with a transport format combination indication field and a pilot field for transmitting a pilot symbol string, and is used for transmitting a fast forward common channel indicator while maintaining compatibility with a system that does not serve the fast forward packet access scheme. A method comprising: a dedicated physical channel of a communication system not using the fast forward packet access service to maintain compatibility between a user terminal supporting the fast forward packet access service and a user terminal not supporting the fast forward packet access service.Determining a field to transmit a fast forward common channel indicator indicating that the fast forward packet access service data exists among the fields of a slot; inserting the fast forward common channel indicator into the determined field and remaining fields of the dedicated physical channel; And multiplexing them to transmit a dedicated physical channel signal.

1 schematically illustrates a forward channel structure of a communication system using a conventional high speed forward packet access scheme.

2 illustrates a dedicated physical channel structure of a conventional code division multiple access communication system;

3 illustrates a structure of a forward dedicated physical channel for transmitting HI of a communication system using a fast forward packet access scheme according to an embodiment of the present invention.

4 illustrates a structure of a forward dedicated physical channel for transmitting HI of a communication system using a fast forward packet access scheme according to another embodiment of the present invention.

FIG. 5 is a diagram illustrating a forward dedicated physical channel structure in a conventional code division multiple access communication system. In particular, FIG. 5 illustrates a forward DPCH structure when SF is 512. FIG.

6 illustrates a structure of a forward dedicated physical channel for transmitting HI of a communication system using a fast forward packet access scheme according to another embodiment of the present invention.

7 is a block diagram showing an internal configuration of a base station apparatus for performing a function in an embodiment of the present invention.

8 is a block diagram illustrating an internal configuration of a user terminal device for performing a function in an embodiment of the present invention.

9 is a diagram illustrating a forward dedicated physical channel structure for transmitting HI of a communication system using a fast forward packet access scheme according to another embodiment of the present invention.

FIG. 10 illustrates a scheme for operating a slot structure of a forward dedicated physical channel of a communication system using a fast forward packet access scheme of the present invention. FIG.

11 is a diagram illustrating a forward dedicated physical channel structure of a communication system using a fast forward packet access scheme according to another embodiment of the present invention.

12 is a diagram illustrating a method of operating the slot structure of FIG. 11 according to another embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present invention will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present invention.

In the present invention, a dedicated physical channel (DPCH) for simultaneously supporting a service of a communication system using a high speed downlink packet access (HSDPA) method and a communication system not using the HSDPA method. Dedicated Physical CHannel (hereinafter referred to as DPCH) structure and a method of transmitting the DPCH will be described. In the present invention, a base station (Node B, referred to as Node B ") is a user terminal (UE). Consider a case in which a user element (hereinafter referred to as UE ") can simultaneously support not only an HSDPA service but also a voice service and a case of providing only an HSDPA service. This will be described in detail as follows. In a communication system that does not support a service, for example, Release-99 will refer to a spreading factor (SF) of a forward DPCH. For example, if the SF is 512 (SF = 512), the number of symbols that can be transmitted in one slot is 5 symbols, and the forward DPCH is a quadrature phase shift keying (QPSK). Since the modulation scheme is used, the number of bits that can be transmitted in one slot is 10 bits (10 bits) when the SF is 512. In general, when the SF is 512, the number of bits that can be transmitted in one slot decreases. If the SF is 256 or less (SF = 256), the number of bits that can be transmitted per slot increases, so that the amount of transmitted data is increased to control the forward DPCH. Not only the information but also the voice data can be transmitted, so in the present invention, the SF of the forward DPCH is set to 256 or less, so that not only the HSDPA service but also Considering the case where the service can be simultaneously supported and the SF of the forward DPCH is 512, only the HSDPA service can be supported and the voice service cannot be supported.

In the above-described Release-99, the slot format divided according to the SF of the forward DPCH and the number of bits of each field is shown in Table 1 below.

In Table 1, when the slot formats are 0 and 1, SF is 512, and the remaining slot formats are when SF is 256 or less. For reference, in Table 1, the A and B formats for each slot format are used in a compressed mode for handover between frequencies or systems.

Meanwhile, in a communication system using the HSDPA scheme, a Node B indicates a fast forward common channel indicator (HI: HS-DSCH Indicator) indicating whether or not there is an HSDPA data packet to be received to the UE through a forward DPCH in order to support the HSDPA service. (Hereinafter referred to as "HI") must be able to be transmitted. Of course, not only the HI but also fields transmitted on the forward DPCH when the HSDPA scheme is not used, that is, Data1, TPC, TFCI, Data2, and Pilot must also be transmitted.

First, a forward DPCH structure capable of simultaneously supporting the HSDPA service and the voice service will be described with reference to FIGS. 3 and 4.

3 is a diagram illustrating a forward dedicated physical channel structure of a communication system using a fast forward packet access method according to an embodiment of the present invention, and in particular, an existing code division multiple access communication system not using the HSDPA method, As an example, a structure of transmitting HI using a pilot field in the forward DPCH structure of Release-99 is shown. 3, the case in which the slot structure in the HSDPA TTI is fixed and the case where the slot structure is variable as described above will be considered. 3 (a) illustrates a structure in which HI is transmitted using a pilot field when all slot structures in the TTI are fixed. 3 (b) and 3 (c) illustrate a structure in which HI is transmitted using only a pilot field in a TTI using a pilot field and using the same slot structure as the existing Release-99 channel for the remaining slots. At this time, (b) and (c) of FIG. 3 separately illustrate the case where the HI-transmitted slot determined by the SHCCH TTI start point and the DPCH slot start point is the first slot and the second slot in the DPCH TTI. .

Referring to (a) of FIG. 3, first, the DPCH includes a structure of a code division multiple access communication system that does not support the existing HSDPA service, for example, a forward dedicated physical channel defined in Release-99. A transmission time interval (TTI) is assumed to be 3 slots, and each of the fields of the slot structure will be described as follows. The Data1 and Data2 fields transmit data for supporting dedicated services such as voice or data for supporting higher layer operations. A Transfer Power Control (TPC) field transmits a downlink transmit power control command for controlling uplink transmit power, and a Transfer Format Combination Indicator (TFCI) field indicates the Data1. And transport format combination information of the Data2 field. The pilot field is a field for transmitting a predetermined pilot symbol string in a system, which is used by the UE to estimate a forward channel state. The HI for the HSDPA service is transmitted to the UE through a newly defined field in the existing Release-99 forward DPCH, as shown in FIG. In this case, the new field for HI is obtained by dividing a portion of the Pilot field while maintaining the Data1, TPC, TFCI, and Data2 fields in the forward DPCH structure of the existing Release-99. If the SF of the forward DPCH of the communication system using the HSDPA scheme is less than the forward DPCH of the Release-99, the number of bits that can be transmitted is increased compared to the Release-99 channel. The HI may be transmitted without any additional reduction in data transmission amount. However, if the SF of the forward DPCH described with reference to (a) of FIG. 3 is the same as the SF of the forward DPCH of Release-99, the number of bits transmitted to the pilot field should be reduced so that HI can be transmitted. As described in FIG. 1, the number of HI information bits to be transmitted is 2 bits. The HI information bits may be transmitted as they are in the HI field of the DPCH channel and may be encoded and transmitted in the NHI bits. If the two bits of HI information are encoded, for example, block coding of (NHI, 2) may be used. In the present invention, it is assumed that the number of bits transmitted in the HI field of the DPCH channel is NHI regardless of whether HI information bits are encoded. If the HI information bits are not encoded, the NHI may be 2, and if encoded, the NHI may be greater than 3, 4, 5, 6, 7, 8, and so on. Therefore, the NHI bit should be reduced in the bits that can be transmitted in the pilot field. For example, the number of pilot bits that can be transmitted for slot format 4 of Table 1 should be reduced to (4-NHI) bits in order to transmit HI for HSDPA service. For the above case, the number of bits to be transmitted in each field NData1, NTPC, NTFCI, and NData2 are as described in FIG. 2, and the number of bits N'Pilot transmitted in the pilot field is from the number of bits NPilot to HI in FIG. It is minus the number of bits NHI to be transmitted. In the case of (a) of FIG. 3, if there is no data packet to be received by the UE, the HI field will be DTX-processed since no HI transmission is necessary. In addition, when HI is transmitted to one of the three slots in the DPCH TTI, HI will not be transmitted to the other two slots, so the HI field will be DTX processed.

Meanwhile, a pattern of pilot bits for estimating the forward channel signal defined in Release-99 is shown in Table 2 below.

The shaded row portion of the pilot pattern shown in Table 2 is a frame synchronization word (FSW) to check whether the frame is synchronized. The remaining unshaded portion of Table 2 is a bit for estimating the state of the forward channel, and SF of the forward DPCH of the communication system supporting the HSDPA service and the communication system not supporting the HSDPA service are the same. In order to transmit the HI, an FSW portion of the pilot field or a portion for estimating a forward channel state may be used. For example, reducing the FSW portion has the advantage of enabling the UE to more accurately estimate the forward channel state, which is important information for the UE, while reducing confidence in frame synchronization, and reducing the forward channel state estimation portion. If so, the UE can be sure of frame synchronization but less confidence in forward channel state estimation. However, if the NPilot is 8 or more, it may be preferable to reduce the FSW part rather than the channel estimation part, since the NPilot is 8 or more, there is more than one part for the FSW. This is because the frame synchronization can be achieved elsewhere at the expense of the frame, and the frame synchronization can be matched at the same time as the channel state estimation is made accurately.

3 (b) and 3 (c) illustrate a case in which the DPCH slot structure is variable in the TTI. That is, only the slot transmitting HI is shown by using the pilot field HI transmission and the remaining slots using the same slot structure as the existing Release-99 channel. Proposing a channel structure as shown in FIG. 3 (b) allocates a HI field to a slot that does not need HI transmission as shown in FIG. 3 (a), and processing DTX means that other information is transmitted to the HI field. Because it may be to exclude the room.

3 (b) shows a channel structure in which the DPCH slot where the SHCCH TTI starting point first meets as described above in FIG. 1 is the first slot in the DPCH TTI, and FIG. 3 (c) shows the DPCH that first meets after the SHCCH TTI starting point. The channel structure is shown when the slot is the second slot in the DPCH TTI. The first slot structure of the TTI in FIG. 3 (b) is a structure capable of transmitting HI as shown in FIG. 3 (a). On the other hand, the remaining two slots except for the first slot in FIG. 3 (b) do not need to transmit HI, and thus may be the same as the structure of the existing Release-99 DPCH channel. In FIG. 3 (c), the second slot structure of the TTI is a structure capable of transmitting HI as shown in FIG. 3 (a). On the other hand, since the remaining two slots except for the second slot in (c) of FIG. 3 do not need to transmit HI, the structure of the existing Release-99 DPCH channel may be the same as that of the existing Release-99 DPCH channel. When using a variable slot structure as shown in c), the variable slot structure will be determined in consideration of the SHCCH and DPCH starting points. Meanwhile, if there is no packet data to be received by the UE for slots transmitting HI in FIGS. 3B and 3C, the HI field will be DTXed. In FIG. 3, the channel structure according to the present invention is fixed. When the slot structure is used and the variable slot structure is used. By generalizing FIG. 3, the present invention can enable the base station to operate the slot structure in the form as shown in FIG. 10 (a) shows a case of using a fixed slot structure as shown in FIG. 3 (a), and may have a slot structure for transmitting HI by allocating HI fields separately for all slots. . At this time, the HI field of the slot where HI is not transmitted will be DTX processed. 10 (b) and (c) show a case where a variable slot structure is used as shown in FIGS. 3 (b) and 3 (c). The slot for transmitting HI by the structure of the DPCH according to the present invention will have a slot structure such as Release-99 if HI is not transmitted as a structure capable of transmitting HI. The HI field will DTX the HI field when there is no HI to transmit. The channel structure of the DPCH in the TTI according to the present invention to be described below will be applied to all three cases of FIG. In the present invention, only the examples of the slot structure of the DPCH through which HI is transmitted will be described for convenience of description.

Meanwhile, as described in FIG. 2, in the 3GPP Release-99 standard, the TFCI field is divided and a part thereof transmits a TFCI of a forward dedicated physical data channel (DPDCH). The remaining part defines what is used to transmit TFCI of DSCH For Node B which supports HSDPA service, when HSDPA data packet is transmitted to UE through HS-DSCH, it is defined in Release-99. If the UE receives the HSDPA service, the TFCI portion for the DSCH of the forward DPCH will be DTX-processed, so that the TFCI field is released as shown in Fig. 4 to support the HSDPA service. Split as defined in the -99 standard, part of which is used for TFCI transmission of the forward DPDCH, The TFCI portion of the DSCH may be used to transmit the HI, in which case the base station does not transmit the HI or the TFCI field for the DSCH for the slot that does not transmit the HI will be processed by DTX. As shown in Table 1, the number of bits of the TFCI is an NTFCI bit (NTFCI = 0, 2, 4, 8.) For example, when TFCI is 2 bits, one bit is TFCI for the forward DPDCH, and the other bit is DSCH. However, considering that the bits required for the HI to be transmitted are NHI bits, only one bit, two bits, or four bits of HI cannot be transmitted to the TFCI field. The remaining HI bits may be transmitted to another field, and a field for transmitting the remaining bits of the HI may be determined as a data field, a pilot field, or the two fields. This will be described with reference to.

4 illustrates a structure of a forward dedicated physical channel of a communication system using a fast forward packet access scheme according to another embodiment of the present invention. In particular, a field for transmitting TFCI information for a DSCH among TFCI fields in Release-99. Is defined as the HI 1 field, and some bits of the HI are transmitted, and a part of the remaining fields is defined as the HI2 field, and the remaining bits of the HI are transmitted. Also, a case in which sufficient bits are allocated to the TFCI field for the DSCH and a portion of the TFCI field is allocated to the HI field is also illustrated.

4 illustrates examples of a slot structure in a slot in which HI is transmitted as described above. As shown in FIG. 10, the base station may use the slot structure for transmitting HI and the slot structure for transmitting HI and the slot structure not transmitting. Here, when there is no HI bit to be transmitted, the HI 1 field and the HI 2 field are DTXed with respect to the slot structure for HI transmission in FIG. 4.

4A illustrates an example in which a part of a TFCI field is used as an HI field in a DPCH slot structure for HI transmission. That is, (a) of FIG. 4 defines a TFCI field defined for DSCH as a field for transmitting HI, and a total NHI bit will be transmitted to the field. In this case, the number of bits NData1, NTPC, NData2, and NPilot to be transmitted in each field are as described with reference to FIG. 2, and the number of bits transmitted in the TFCI field is N0TFCI, which is NTFCI NHI. Referring to Table 1 above, for example, when the spreading rate is 128 or more, the number of bits NTFCI that can be transmitted in the TFCI field is 0 or 2. In the present invention, for convenience of description, the slot format of the compression mode will be excluded from the example. Then, in Release-99, 0 or 1 bit will be transmitted to the TFCI field for the DSCH. That is, the number of bits NHI of the HI field will be allocated to one. As described in FIG. 1, since the information bits of the HI are two bits, when the spreading rate is actually 128 or more, the HI information may not be transmitted. Therefore, other fields as well as the TFCI field for the DSCH should be used. On the other hand, in Table 1, when the spreading rate of the DPCH is 64 or less, TFCI 8 bits may be allocated, so that the number NHI of the HI field according to the present invention may be assigned 4. In this case, since the number of bits of the HI field is 4, HI may be transmitted using block coding of (4,2).

FIG. 4B illustrates an example in which a part of a TFCI field is a HI 1 field and a part of a pilot field is an HI 2 field in the HI channel DPCH slot structure. In FIG. 4B, the N1HI1 bit is transmitted to the HI 1 field and the N1HI2 bit is transmitted to the HI 2 field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N1HI1 + N1HI2. In this case, the number of bits NData1, NTPC, and NData2 to be transmitted in each field are as described in FIG. 2, and the number of bits transmitted in the TFCI field is N1TFCI, which is NTFCI N1HI1. The number of bits transmitted in the pilot field is Npilot N1HI2. Referring to Table 1 above, for example, when the spreading rate is 128 or more, the number of bits NTFCI that can be transmitted in the TFCI field is 0 or 2. Then, in Release-99, 0 or 1 bit will be transmitted to the TFCI field for the DSCH. That is, 1 may be allocated to the number N1HI1 of the HI 1 field. If 2 can be allocated as the number N1HI2 of the HI 2 field obtained by dividing the pilot field of Release-99, the total number of HI bits NHI that can be transmitted is 3 bits, so that HI information bit 2 is performed using a block coding of (3, 2). Will be able to send bits. In Table 1, when the spreading rate is 64 or less, TFCI 8 bits may be allocated, so that the number of bits N1HI1 of the HI 1 field according to the present invention may be assigned 4. At this time, if 2 is allocated as the number N1HI2 of the HI 2 field, the NHI that can be transmitted becomes 6 and HI may be transmitted using a block coding of (6,2).

In addition, a dedicated physical channel structure similar to that of FIG. 4B is shown in FIG. 4C. FIG. 4C is a diagram illustrating a DPCH slot structure for HI transmission according to another embodiment of the present invention, in which a part of a TFCI field is a HI 1 field, a data 2 and a part of a pilot are HI 2 fields. Shows. In FIG. 4C, the N2HI1 bit is transmitted to the HI 1 field and the N2HI2 bit is transmitted to the HI 2 field over the Data2 field and the Pilot field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N2HI1 + N2HI2. In this case, the number of bits NData1 and NTPC to be transmitted in each field is as described with reference to FIG. 2, and the number of bits transmitted in the TFCI field is N2TFCI, which is NTFCI N2HI1. The number of bits transmitted in the Data2 field depends on how many bits of the Data2 field are allocated to the HI 2 field. For example, if the K bits of the Data2 field are allocated to the HI 2 field, the number of bits N1Data2 transmitted to the Data2 field is NData2 K. The number of bits N 2 Pilot transmitted in the pilot field is then NPilot (N 2 HI 2 K). Referring to Table 1 as shown in (b) of FIG. 4, for example, when the diffusion ratio of DPCH is 128 or more, N2HI1 may be 1, and NHI is 3 when N2HI2 is assigned to 2. Therefore, the base station can transmit HI using block coding of (3,2). Allocating N2HI2 to 2 means splitting one bit into the Data2 field and one bit into the pilot field. If the spreading rate of the DPCH is 64 or less, the base station may allocate 4 bits to N2HI1 and transmit a block coded HI of (4 + N2HI2, 2) by allocating N2HI2 bits to the HI 2 field.

FIG. 4D is a diagram illustrating a DPCH slot structure for HI transmission according to another embodiment of the present invention, in which a part of a TFCI field is a HI 1 field and a part of a Data1 field is an HI 2 field. Illustrated. In FIG. 4D, the N3HI1 bit is transmitted to the HI 1 field and the N3HI2 bit is transmitted to the HI 2 field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N3HI1 + N3HI2. In this case, the number of bits NTPC, NData2, and NPilot to be transmitted in each field is as described in FIG. 2, and the number of bits transmitted in the TFCI field is N3TFCI, which is NTFCI N1HI1. The number of bits N1Data1 transmitted to the Data1 field is NData1 N3HI2. Referring to Table 1, for example, when the diffusion ratio of the DPCH is 128 or more, N3HI1 may be 1, and NHI is 3 when N3HI2 is assigned to 2. Therefore, the base station can transmit HI using block coding of (3,2). If the spreading rate of the DPCH is 64 or less, the base station may allocate 4 bits to N3HI1 and transmit N3HI2 bits in the HI 2 field to transmit block coded HI of (4 + N2HI2, 2). ) Is a diagram illustrating a forward dedicated physical channel structure of a communication system using a fast forward packet access scheme according to another embodiment of the present invention. In particular, in Release-99, a field for transmitting TFCI information for a DSCH is shown. It is shown that some bits of HI are defined as HI 1 fields and some bits of Data 2 fields are transmitted as HI 2 fields. In this case, the number of bits NData1, NTPC, and NPilot to be transmitted in each field are as described in FIG. 2, and the number of bits transmitted in the TFCI field is N4TFCI, which is NTFCI N4HI1. The number of bits transmitted in the Data2 field is N2Data2, which is NData N4HI2. Referring to Table 1, for example, when the diffusion ratio of the DPCH is 128 or more, N4HI1 may be 1, and NHI is 3 when N4HI2 is assigned to 2. Therefore, the base station can transmit HI using block coding of (3,2). If the spreading rate of the DPCH is 64 or less, the base station may allocate 4 bits to N4HI1 and transmit a block coded HI of (4 + N2HI2, 2) by allocating N4HI2 bits to the HI 2 field.

In the case of transmitting HI by the method as shown in FIG. 4, there is an advantage that the UE can receive the forward DPCH without distinguishing between the Release-99 forward DPCH slot structure and the forward DPCH slot structure supporting HSDPA service. That is, if the HI 1 field, which is a TFCI field for the DSCH, is DTX, the UE knows that there is no HI information to receive, that is, a Release-99 forward DPCH in which the HI is not transmitted, and if the bit is transmitted to the H1 1 field, the HSDPA service is transmitted. This is because it can be seen that the forward DPCH for. That is, when the HI 1 field is DTX, since it is a forward DPCH of Release-99, data or pilot information, which has been reduced for the HSDPA service, may be transmitted to the HI 2 field. If a bit is transmitted to the HI 1 field, the HI DP is transmitted by reducing the Data or Pilot field to the HI 2 field since it is a forward DPCH for supporting the HSDPA. As a result, when the DPCH slot structure as shown in FIG. 4 is used, the HI 1 field may be used as an indicator to distinguish between a channel for release-99 or a channel supporting HSDPA service according to whether the HI 1 field is DTX. The above concept is the same as the concept of variable slot structure operation of the base station described with reference to FIGS. 10 (b) and 10 (c). That is, in FIG. 10 (b) and (c), the base station variably used the slot structure in which HI is transmitted and the slot structure in which HI is not transmitted by timing of SHCCH and DPCH. 4 illustrates a case in which a base station variably operates a slot structure for transmitting HI and a slot structure for not transmitting HI depending on whether the TFCI for the DSCH is DTX.

In FIG. 4, the TFCI field is divided as defined in the Release-99 standard, and a part of the TFCI field is used for TFCI transmission of the forward DPDCH, and the other part, that is, a field different from the part that previously transmitted the TFCI of the DSCH, is used. The case of transmitting the HI has been described. In the present invention, another method of using the entire TFCI field for HI transmission is illustrated in FIG. 11. FIG. 11 illustrates a method for transmitting HI through the TFCI field for the DPDCH and the TFCI field for the DSCH of three slots in the TTI. In FIG. 11, as an example, it is assumed that a slot to which HI is to be transmitted is the first slot. HI may be transmitted to the second slot in the TTI, but for convenience, it is assumed that HI is transmitted to the first slot. Then, the base station allocates the TFCI field for the DPDCH and the DSCH of the first slot to the HI field. At this time, if there is TFCI information for the DPDCH to be transmitted to the first slot, the TFCI information not transmitted to the first slot may be transmitted to the TFCI field for the DSCH of the second slot or the third slot. FIG. 11 illustrates an example of transmitting a TFCI for a DPDCH not transmitted to the first slot as a TFCI field for the DSCH of the second slot. Of course, if there is TFCI information to be transmitted in the second slot, the information will be transmitted in the TFCI field for the DPDCH of the second slot.

In this case, the number of bits to be transmitted in each field of the first slot in the TTI is as described in FIG. 2 and the number of bits transmitted in the HI field, which was the TFCI field in Release-99, is NHI. to be. For example, when the spreading ratio of the DPCH is 128 or more, 0 or 2 bits are allocated to the TFCI field. Therefore, the number of bits that can be transmitted in the HI field of FIG. 11 is 2 bits. That is, NHI is 2. Therefore, the base station can transmit 2 bits of HI information to the HI field without coding. Then, NData1, NTPC, NData2, and Npilot are transmitted in each field for the second slot in the TTI. If the spread rate of the DPCH is 128 or more, the base station transmits one bit of TFCI for the DPDCH to be transmitted to the second slot and one bit of TFCI for the DPDCH not transmitted to the first slot in the TFCI field of the second slot. If the spreading rate of the DPCH is 64 or less, the base station can allocate 8 bits to the TFCI field, so that the NHI is 8, thereby transmitting a block coded HI of (8, 2). If the spread rate of the DPCH is 64 or less, the base station will transmit TFCI four bits for the DPDCH to be transmitted to the second slot and TFCI four bits for the DPDCH not transmitted to the first slot in the TFCI field of the second slot.

As shown in FIG. 11, when HI is transmitted to the first slot when the slot structure of the forward DPCH is shown, TFCI information for the DPDCH not transmitted to the first slot is transmitted to the second slot or the third slot. Problems that may occur in this case will be described with reference to FIG. 12. Recall that first in Release-99, TFCI information is transmitted in the TFCI field for the DPDCH over several slots in one frame. Then, the terminal side may decode the frame by collecting TFCI information transmitted over several slots. 12 illustrates an example in which the TTI starting point of the SHCCH is located before the 14th slot of the nth frame of the DPCH. At this time, since the first slot after the TTI start point of the SHCCH is the 14th slot of the nth frame of the DPCH, the base station will transmit HI to the DPCH slot 14. If the slot structure of FIG. 12 is the same as the slot structure of FIG. 11, TFCI information for DPDCH is not transmitted to the 14th slot. Then, as described with reference to FIG. 11, TFCI information for the DPDCH in the DPCH should be transmitted to the first slot of the (n + 1) th frame. However, the TFCI information that is not transmitted to the 14th slot is a TFCI for the nth frame and should not be transmitted to the next frame. Therefore, when using the slot structure as shown in FIG. 11, the base station needs to limit the position of the slot for transmitting the TFCI for the DPDCH that cannot be transmitted due to HI to the slot of the frame.

So, for example, when transmitting HI to the first slot within the HSDPA TTI and TFCI for the DPDCH to the next slot, the number of slots for transmitting the TFCI within the frame can be expressed by the following equation.

TFCI for DPDCH Slot number to transmit = (HI transmit slot number + 1) mod 15

Using the example of FIG. 11, since the slot number for HI transmission is 14, the TFCI for the DPDCH not transmitted in slot 14 may be transmitted to the 0th of the nth frame according to Equation (1). Likewise, when the HI is transmitted to the first slot in the HSDPA TTI and the TFCI for the DPDCH is transmitted to the third slot, the number of slots for transmitting the TFCI in the frame can be expressed by the following equation.

TFCI for DPDCH Slot number to transmit = (HI transmit slot number + 2) mod 15

Using the example of FIG. 11, since the slot number for transmitting HI is 14, the TFCI for the DPDCH not transmitted in the slot 14 may be transmitted to the first n-th frame according to Equation 2.

Equation (1) and (2) are the TFCI for the DPDCH not transmitted with the entire TFCI field as the HI field in the slot for transmitting HI according to the present invention, which will be described below. will be.

FIG. 13 illustrates methods for using the entire TFCI field as the HI 1 field and a part of the remaining field as the HI 2 field for HI transmission. FIG. 13A illustrates a method of allocating a TFCI field for a DPDCH and a TFCI field for a DSCH to a HI 1 field and a part of a pilot field to an HI 2 field among three slots in a TTI. It is shown.

In FIG. 13A, the N5HI1 bit is transmitted to the HI 1 field and the N5HI2 bit is transmitted to the HI 2 field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N5HI1 + N5HI2. In the above case, the number of bits NData1, NTPC, and NData2 to be transmitted in each field are as described with reference to FIG. 2, and the number of bits transmitted in the pilot field is N3Pilot and NPilot N5HI2. Referring to Table 1 above, for example, when the spreading rate is 128 or more, the number of bits NTFCI that can be transmitted in the TFCI field is 0 or 2. That is, 2 may be allocated to the number N5HI1 of the HI 1 field. If 2 can be allocated as the number N5HI2 of the HI 2 field obtained by dividing the pilot field of the release-99, the total number of HI bits that can be transmitted NHI is 4 bits, so that HI information bit 2 using the block coding of (4, 2) Will be able to send bits. In Table 1, when the spreading rate is 64 or less, TFCI 8 bits may be allocated, so that the number of bits N 5 HI 1 of the HI 1 field according to the present invention may be allocated 8. At this time, if 2 is allocated as the number N5HI2 of the HI2 field, the NHI that can be transmitted becomes 10, so that HI can be transmitted using a block coding of (10,2).

As shown in FIG. 11, the TFCI for the DPDCH not transmitted to the first slot will be transmitted to the second slot. In FIG. 13A, the TFCI for the DPDCH is transmitted to the second slot, but the TFCI for the DPDCH may be transmitted to the third slot. 13A shows a variable slot structure. This is to transmit other information to the slot where the HI is not transmitted as in the case of (b) and (c) of FIG. That is, since HI does not need to be transmitted in the second and third slots of FIG. 13A, the original pilots are transmitted without allocating the pilot field portion to the HI 2 field. The slot structure fixed with respect to FIG. 13A may be used. Then, the HI 2 field is allocated to the second and third slots, and since there is no HI bit to be transmitted, the DTX process will be performed. The contents of the slot structure described with reference to FIG. 13A may be similarly applied to FIGS. 13B and 13C.

FIG. 13 (b) illustrates a method of allocating a part of the Data2 field to the HI 2 field as the HI 2 field as the TFCI field for the DPDCH and the TFCI field for the DSCH of the three slots in the TTI. It is shown. In FIG. 13B, N6HI1 bits are transmitted in the HI 1 field and N6HI2 bits are transmitted in the HI 2 field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N6HI1 + N6HI2. In this case, the number of bits NData1, NTPC, and NPilot to be transmitted in each field are as described with reference to FIG. 2, and the number of bits transmitted in the Data2 field is N3Data2 and NData2 N6HI2. Referring to Table 1 above, for example, when the spreading rate is 128 or more, the number of bits NTFCI that can be transmitted in the TFCI field is 0 or 2. That is, 2 may be allocated to the number N6HI1 of the HI 1 field. If 2 can be allocated as the number of bits N6HI2 of the HI2 field obtained by dividing the Data2 field of Release-99, the total number of HI bits that can be transmitted NHI is 4 bits, so that the HI information bit 2 using the block coding of (4, 2) Will be able to send bits. In Table 1, when the spreading rate is 64 or less, TFCI 8 bits may be allocated, so that the number of bits N6HI1 of the HI 1 field according to the present invention may be allocated 8. At this time, if 2 is allocated to the number of bits N6HI2 of the HI 2 field, the NHI that can be transmitted becomes 10, so that HI can be transmitted using a block coding of (10,2).

FIG. 13 (c) shows that the TFCI field for the DPDCH and the TFCI field for the DSCH of the three slots in which the HI is to be transmitted are allocated to the HI 1 field as the HI 2 field and the HI 2 field. The room is shown. In FIG. 13C, N7HI1 bits are transmitted in the HI 1 field and N7HI2 bits are transmitted in the HI 2 field. Since the number of HI bits to be transmitted is referred to as NHI bits above, NHI = N7HI1 + N7HI2. In the above case, the number of bits NData1, NTPC, and NPilot to be transmitted in each field are as described with reference to FIG. 2. The number of bits transmitted in the Data2 field depends on how many bits of the Data2 field are allocated to the HI 2 field. For example, if K bits of the Data2 field are allocated to the HI 2 field, the number of bits N4Data2 transmitted to the Data2 field is NData2 K. The number of bits N4Pilot transmitted in the pilot field is then NPilot (N7HI2 K). Referring to Table 1 above, for example, when the spreading rate is 128 or more, the number of bits NTFCI that can be transmitted in the TFCI field is 0 or 2. That is, 2 may be allocated to the number N7HI1 of the HI 1 field. If 2 can be allocated as the number of bits N7HI2 of the HI2 field obtained by dividing the Data2 field of Release-99, the total number of HI bits that can be transmitted NHI is 4 bits, so that HI information bit 2 using block coding of (4, 2) Will be able to send bits. In Table 1, when the spreading rate is 64 or less, TFCI 8 bits may be allocated, so that the number of bits N7HI1 of the HI 1 field according to the present invention may be allocated 8. At this time, if 2 is allocated as the number N7HI2 of the HI2 field, the NHI that can be transmitted becomes 10, so that HI can be transmitted using a block coding of (10,2).

9 is a diagram illustrating a forward dedicated physical channel structure of a communication system using a fast forward packet access scheme according to another embodiment of the present invention. In particular, a part of the Data2 field is defined as an HI field. The case where the HI field is defined over both the Data2 field and the pilot field is shown. FIG. 9A illustrates a structure of a DPCH slot for HI transmission, and illustrates an example in which a part of the Data2 field is used as an HI field. In FIG. 9A, the number of HI bits to be transmitted is NHI bits. In this case, the number of bits NData1, NTPC, NTFCI, and NPilot to be transmitted in each field are as described in FIG. 2, and the number of bits N3Data2 transmitted in the Data2 field is NData2 NHI. FIG. 9B is a diagram illustrating a DPCH slot structure for HI transmission, and shows an example in which a part of the Data2 field and a part of the pilot field are simultaneously used as HI fields. The number of HI bits to be transmitted to the HI field in FIG. 9B is the NHI bits. In the above case, the number of bits to be transmitted in each field is NData1, NTPC, and NTFCI as described in FIG. 2, and the number of bits transmitted in the Data2 field depends on how many bits of the Data2 field are allocated to the HI field. For example, if L bits of the Data2 field are allocated as HI fields, the number of bits N4Data2 transmitted to the Data2 field is NData2 L. Then, the number of bits N3Pilot transmitted in the pilot field becomes NPilot (NHI L). Next, a slot structure when the SF of the forward DPCH defined in the conventional Release-99 is 512 will be described with reference to FIG. 5.

FIG. 5 is a diagram illustrating a forward dedicated physical channel structure in a typical code division multiple access communication system. In particular, FIG. 5 illustrates a forward DPCH structure when SF is 512.

Referring to FIG. 5, if the SF of the forward DPCH is 512, the forward DPCH is composed of a TPC, TFCI, Data2, and Pilot fields without the Data1 field according to slot formats 0 and 1 of Table 1 above. As described above, when SF is 512, the forward DPCH may be for physical layer control of another common channel, rather than providing a voice service. For example, the forward DPCH having the slot format 0 of Table 1 is used to control the Common Packet Channel (CPCH) defined in Release-99 to transmit packets in the reverse direction. The forward DPCH uses the TPC command for controlling the transmission power of the CPCH of the UE as the TPC field and the higher signaling information for controlling the CPCH as the Data2 field. In the 3GPP standard, the Data2 field for CPCH control is called CCC (CPCH Control Command). In FIG. 5, MTPC, MTFCI, MData2, and MPilot refer to the number of bits transmitted in each field.

In FIG. 5, a forward DPCH structure of a conventional code division multiple access communication system that does not support HSDPA service, in particular, a forward DPCH structure when SF is 512 is described. In contrast, a forward DPCH structure of a communication system supporting HSDPA service In particular, another example of the forward DPCH structure when SF is 512 will be described with reference to FIG. 6.

6 illustrates a structure of a forward dedicated physical channel of a communication system using a fast forward packet access scheme according to another embodiment of the present invention.

Referring to FIG. 6, if the UE receives only the HSDPA service from the Node B and receives no voice service, the Node B will transmit a forward DPCH having an SF of 512 to the UE to support the HSDPA service as shown in FIG. 6. If the SF of the forward DPCH for supporting the HSDPA is the same as the SF of the Release-99 forward DPCH described with reference to FIG. 5, that is, if SF is 512, HI may be reduced by reducing one field in the forward DPCH structure as described with reference to FIG. You will have to create a field to send. Of course, as described with reference to FIG. 4, the HI may be transmitted by reducing the field in various ways. However, in order to transmit the HI, it is preferable to reduce the number of bits of the pilot field necessary for estimating the state of the forward channel, and to transmit the HI by reducing the number of bits of the Data2 field in terms of demodulation performance of the UE. can do. FIG. 6 illustrates an example of reducing Data2 of FIG. 5 to transmit HI. In the above case, the number of bits MTPC, MData2, and MPilot to be transmitted in each field is Mdata2-NHI as M1Data2 in FIG. 5 and the number of bits transmitted in the Data2 field. Next, an apparatus for transmitting / receiving a forward DPCH signal to be compatible with both the communication system using the HSDPA method and the communication system not using the HSDPA method as described above will be described with reference to FIGS. 7 and 8. do.

7 is a block diagram illustrating an internal configuration of a base station apparatus for performing a function in an embodiment of the present invention.

Referring to FIG. 7, data 701 to be transmitted through the DPCH is channel coded by the encoder 702 and rate matched by the number of bits to be transmitted in the DPCH by the rate matching unit 703. In FIG. 1, the HI information bit is referred to as two bits. In the present invention, the HI information bits may be transmitted as they are in the downlink DPCH or the HI bits may be coded as NHI bits. In FIG. 7, the encoder 726 is used to include the case where the HI 704 is coded. For example, the encoder 726 may block code (NHI, 2) or do other convolutional coding. If the HI 704 is not coded, the encoder 726 will output the HI information bit as it is. The output of the rate matching unit 703, the output of the encoder 726, the TFCI 705, the pilot 706, and the TPC 707 are applied to the multiplexer 708 and output as one bit stream. Here, as shown in FIG. 10, the controller 727 includes both a case where the DPCH slot structure in the TTI is fixed as a slot structure for HI transmission and a case where the slot structure for HI transmission and a slot structure not transmitting HI are variable. need. 11 and 13, when the TFCI field for the DPDCH is allocated to the HI field, the control unit 727 is required to transmit TFCI information that cannot be transmitted to another slot. When the DPCH slot structure is variable, the controller 727 controls the multiplexer 708 to make the slot structure for HI transmission different from the slot structure for HI transmission. For example, as shown in (b) of FIG. 10, since the first slot in the TTI is an HI transmission slot, the controller 727 allows the multiplexer 708 to allocate an HI field. 10 (b), since the second and third slots in the TTI are slots that do not transmit HI, the controller 727 is configured to multiplex the multiplexer 708 into the DPCH slot structure of the existing Release-99. To control. If the base station operates a fixed slot structure as shown in (a) of FIG. 10, the controller 727 will not play any role. 11 and 13, the control unit 727 can transmit the TFCI that cannot be transmitted due to HI to another slot in the same frame using the equations 1 and 2 when the slot structure of the DPCH is operated as shown in FIGS. 708 is controlled.

Since the structure of the forward dedicated physical channel for transmitting HI described with reference to FIGS. 3, 4, 6, 9, 11, and 13 is different, a process of generating one bit stream in the multiplexer 708 This is different. For convenience of explanation, it is assumed that the SF of the forward DPCH for supporting the HSDPA service is the same as the SF of the forward DPCH of Release-99. In the case of FIG. 3, the multiplexer 708 clears the NHI bits and sends HI instead of the Pilot bits defined in Release-99 to transmit HI. In the case of FIG. 4, the multiplexer 708 should operate to transmit the HI partial bit from the HI part bit and the other field to the TFCI field for the DSCH to transmit the HI. In the case of FIG. 6, the multiplexer 708 operates to reduce the one field of the Pilot or Data2 field defined in Release-99 so that the HI NHI bit is transmitted. In the case of FIG. 9, the multiplexer 708 should operate to split the Data2 field defined in Release-99 or to simultaneously divide the Data2 field and the pilot field to transmit HI NHI bits.

The bit stream is changed into two bit streams by reference numeral 709, and the spreader 710 spreads the two bit streams using the same channelization code to be orthogonal to signals using different channelization codes. . In this case, the two bit streams I and Q signals of the spreader output are output as one complex stream by the multiplier 711 and the adder 712. The complex stream output is multiplied by a complex mixed code on a chip-by-chip basis by the mixer 713 to be distinguished from a signal using another mixed code. The complex mixing code multiplied by the combiner is used to distinguish the base stations. The output of the mixer 713 is again multiplied by the channel gain by the multiplier 714.

Meanwhile, FIG. 7 also shows a transmission apparatus for the SHCCH, where the HS-DSCH control information 715 is converted into two bit streams by the reference numeral 716, spread by the spreader 717, and again a multiplier 718. And the adder 719 convert the two bit streams into one complex stream. The complex output of the adder 719 is multiplied by the complex mixer 720 in units of chips by the mixer 720 and then multiplied by the channel gain in the multiplier 721. The forward DPCH output of reference 714 and the SHCCH output of reference 721 are added at summer 722, modulated at modulator 723, converted to RF band signals at RF section 724, and then transmitted via antenna 725. do. In FIG. 7, it is assumed that the forward DPCH and the SHCCH are mixed by different mixing codes. However, a method and an apparatus for transmitting the two channels using the same mixing code and using different channelization codes are also possible.

In FIG. 7, the base station apparatus is described. Next, the user terminal apparatus will be described with reference to FIG. 8.

8 is a block diagram showing an internal configuration of a user terminal device for performing a function in an embodiment of the present invention.

Referring to FIG. 8, the RF band signal received by the antenna 801 is converted into a baseband signal by the RF unit 802, and demodulated by the demodulator 803 to the two demixers 804 and 818. Is approved. A forward DPCH signal is output from the demixer 804, and a SHCCH signal is output from the demixer 818. The complex output of 804 is separated into a real signal I and an imaginary signal Q by 805. The I and Q signals are despread by multiplying the channelization codes in the despreader 806. In addition, the output I and Q signals of 818 are despread by multiplying the channelization codes in the despreader 819. The I and Q output signals of the despreader 806 are applied to the demultiplexer 807 so that the demultiplexer 807 outputs the Pilot 808 signal. The pilot signal 808 is applied to the channel estimator 809 to apply channel estimation values through distortion estimation by the wireless channel to the channel compensators 810 and 821. The channel compensators 810 and 821 compensate for the distortion caused by the wireless channel using the channel estimate. The channel compensator 810 outputs data of DPCH as two bit streams, and the channel compensator 822 outputs data of SHCCH as two bit streams. The 822 converts the SHCCH data applied to the two bit streams into one bit stream and finally outputs the HS-DSCH control information 823. The 811 converts data of the DPCH applied to two bit streams into one bit stream, and the output bit stream of the 811 outputs the TPC 813, TFCI 814, and HI by the demultiplexer 812.

In this case, as shown in FIG. 7, the controller 825 includes both a case in which the DPCH slot structure in the TTI is fixed as a slot structure for HI transmission and a case in which the slot structure for HI transmission and a slot structure not transmitting HI are variable. need. The controller 825 controls the multiplexer 812 to distinguish and demultiplex whether the information in the TFCI field is HI information or TFCI information for DPDCH when receiving the DPCH of the slot structure shown in FIGS. 11 and 13. do. When the DPCH slot structure is variable, the controller 825 controls the demultiplexer 812 to demultiplex into a slot structure for transmitting HI and a slot structure for not transmitting HI. The fixed and variable slot structure should be promised by the terminal and the base station. When the variable slot structure is used in the base station side of FIG. 7, the control unit 812 of the terminal side must control to demultiplex differently by distinguishing a slot structure for transmitting HI and a slot structure for not transmitting. When the fixed slot structure is used at the base station side of FIG. 7, the terminal side also uses a fixed slot structure, and thus the role of the controller 825 is not necessary.

When the base station of FIG. 7 codes HI for the HI of the demultiplexer 812 and transmits the HI, the HI 815 is finally decoded through the decoder 824. Otherwise, decoder 824 outputs HI from demultiplexer 812 to the HI 815 output.

The demultiplexer 812 also outputs a downlink data signal. The downlink data signal is channel-decoded by the decoder 816 to output downlink data 817. In FIG. 8, it is assumed that a radio channel is estimated using a pilot transmitted through a DPCH. However, it is also possible to estimate a radio channel using a pilot transmitted through a shared channel.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the present invention improves system performance by proposing a dedicated physical channel structure that maintains compatibility with a communication system that does not use the fast forward packet access method in a communication system that uses the fast forward packet access method. Has In addition, according to the spread rate of the dedicated physical channel, it is advantageous to adaptively control a field for transmitting a fast forward common channel indicator indicating that the fast forward packet access service exists, thereby improving system efficiency.

Claims (15)

A system that does not support a high speed forward packet access service transmits user data field for transmitting user data, a transmit power control field for transmitting a command for controlling reverse transmission power, and transmit format combination indication information of the user data. It has a dedicated physical channel structure multiplexed with a transport format combination indication field and a pilot field for transmitting a pilot symbol string, and is used for transmitting a fast forward common channel indicator while maintaining compatibility with a system that does not serve the fast forward packet access scheme. In the apparatus, In a field of a dedicated physical channel slot of a communication system that does not use the fast forward packet access service to maintain compatibility between the user terminal that supports the fast forward packet access service and the user terminal that does not support the fast forward packet access service. A controller for determining a field to transmit a fast forward common channel indicator indicating that the fast forward packet access service data is present; And a dedicated physical channel transmitter for inserting the fast forward common channel indicator into the determined field under the control of the controller and multiplexing the remaining fields of the dedicated physical channel for transmission. The method of claim 1, When the controller determines a field to transmit the fast forward common channel indicator as a pilot field, the controller does not support the spread rate of the dedicated physical channel of the communication system supporting the fast forward packet access service and the fast forward packet access service. And the fast forward common channel indicator determines an area to be transmitted in the pilot field by comparing the spread rates of the dedicated physical channels of the communication system. The method of claim 2, The controller transmits data transmitted through the pilot field when the spreading rate of the dedicated physical channel of the communication system supporting the fast forward packet access service is greater than the spreading rate of the dedicated physical channel of the communication system not supporting the fast forward packet access service. The amount is reduced by the number of bits needed for the fast forward common channel indicator transmission. The method of claim 1, When the controller determines a field to be transmitted in the fast forward common channel indicator as a transport format combination indication field and a user data field, the controller discontinuously transmits the transport format combination indication field when the fast forward common channel indicator is not transmitted. Said device characterized by processing. The method of claim 4, wherein The controller selects the second field from the transport format combination display field including a first field for transmitting transport format combination indication information of a dedicated physical data channel and a second field for transmitting transport format combination indication information of a forward common channel. Select and control the forward common channel indicator to be transmitted. The method of claim 1, When the controller determines a field to be transmitted with the fast forward common channel indicator as a transport format combination indication field and a pilot field, the controller discontinuously processes the transport format combination indication field when the fast forward common channel indicator is not transmitted. The device, characterized in that. The method of claim 6, The controller selects the second field from the transport format combination display field as a first field for transmitting transport format combination indication information of a dedicated physical data channel and a second field for transmitting transport format combination indication information of a forward common channel. And control the forward common channel indicator to be transmitted. A system that does not support a high speed forward packet access service transmits user data field for transmitting user data, a transmit power control field for transmitting a command for controlling reverse transmission power, and transmit format combination indication information of the user data. It has a dedicated physical channel structure multiplexed with a transport format combination indication field and a pilot field for transmitting a pilot symbol string, and is used for transmitting a fast forward common channel indicator while maintaining compatibility with a system that does not serve the fast forward packet access scheme. In the method, In a field of a dedicated physical channel slot of a communication system that does not use the fast forward packet access service to maintain compatibility between the user terminal that supports the fast forward packet access service and the user terminal that does not support the fast forward packet access service. Determining a field to transmit a fast forward common channel indicator indicating that the fast forward packet access service data exists; And inserting the fast forward common channel indicator into the determined field and multiplexing with the remaining fields of the dedicated physical channel to transmit a dedicated physical channel signal. The method of claim 8, When the field to which the fast forward common channel indicator is transmitted is determined to be a pilot field, a spread rate of a dedicated physical channel of a communication system supporting the fast forward packet access service and a dedicated physical of a communication system not supporting the fast forward packet access service And comparing the spread rates of the channels to determine a region to be transmitted in the pilot field by the fast forward common channel indicator. The method of claim 9, If the spreading rate of the dedicated physical channel of the communication system supporting the fast forward packet access service is greater than the spreading rate of the dedicated physical channel of the communication system not supporting the fast forward packet access service, the amount of data transmitted through the pilot field is determined. And reducing the number of bits necessary for fast forward common channel indicator transmission. The method of claim 8, If the field for transmitting the fast forward common channel indicator is determined as a transport format combination display field and a user data field, discontinuously transmitting the transport format combination display field if the fast forward common channel indicator is not transmitted. The method characterized in that. The method of claim 11, The forward common channel indicator may include a first field for transmitting transport format combination indication information of the dedicated physical data channel and a second field for transmitting transport format combination indication information of the forward common channel. The method of claim 2, characterized in that transmitted through the second field. The method of claim 8, If the field for transmitting the fast forward common channel indicator is determined to be a transport format combination indication field and a pilot field, discontinuously transmitting the transport format combination indication field when the fast forward common channel indicator is not transmitted. The method characterized in that. The method of claim 13, The forward common channel indicator may include a first field for transmitting transport format combination indication information of the dedicated physical data channel and a second field for transmitting transport format combination indication information of the forward common channel. The method of claim 2, characterized in that transmitted through the second field. A system that does not support a high speed forward packet access service transmits user data field for transmitting user data, a transmit power control field for transmitting a command for controlling reverse transmission power, and transmit format combination indication information of the user data. It has a dedicated physical channel structure multiplexed with a transport format combination indication field and a pilot field for transmitting a pilot symbol string, and is used for transmitting a fast forward common channel indicator while maintaining compatibility with a system that does not serve the fast forward packet access scheme. In the method, In a field of a dedicated physical channel slot of a communication system that does not use the fast forward packet access service to maintain compatibility between the user terminal that supports the fast forward packet access service and the user terminal that does not support the fast forward packet access service. Determining a field to transmit a fast forward common channel indicator indicating that the fast forward packet access service data exists; Inserting the fast forward common channel indicator into the determined field and multiplexing with the remaining fields of the dedicated physical channel to transmit a dedicated physical channel signal; Inserting and transmitting information data transmitted in a field into which the fast forward common channel indicator is inserted in the same field as the determined field in another slot within a transmission time period to which the dedicated physical channel slot into which the fast forward common channel indicator is inserted is transmitted; The method characterized in that it comprises a.