KR20090102525A - Method of transmitting packet channel request in egprs2 system - Google Patents

Abstract

PURPOSE: A packet channel request message transmission method is EGRPS2 system supporting a packet service is provided to maintain an existing packet channel request message and an EGPRS packet channel request message by supplying the EGPRS2 packet channel request message. CONSTITUTION: A packet channel request message transferring method requesting the uplink resource allocation in EGPRS2(Enhanced General Packet Radio Service Phase 2) is as follows. The training sequence in which it depends on EGPRS2-A or the EGPRS2-B is mapped on the access. The packet channel request message is transmitted through the access burst(S210).

Description

Method of transmitting packet channel request message in EGPRS2 system

The present invention relates to wireless communication, and more particularly, to a method for transmitting a packet channel request message in an enhanced general packet radio service phase 2 (EGPRS2) system.

Global System for Mobile communication (GSM) is a wireless technology developed as a system for standardizing wireless communication systems in Europe and is widely used worldwide. General Packet Radio Service (GPRS) was introduced to provide a packet switched data service in a circuit switched data service provided by GSM. EDGE (Enhanced Data Rate for GSM Evolution) increases data rates by adopting 8-Phase Shift Keying (PSK) instead of Gaussian Minimum Shift Keying (GMSK). Enhanced General Packet Radio Service (EGPRS) represents GPRS using EDGE.

A physical channel used for GPRS / EGPRS traffic is called a packet data channel (PDCH). A logical channel for user data is called a Packet Data Traffic Channel (PDTCH), a logical channel for dedicated signaling is called a Packet Associated Control Channel (PACCH), and a logical channel for general control signaling is a Packet Common Traffic Channel (PCCCH). Control Channel).

Recently, Enhanced General Packet Radio Service Phase 2 (EGPRS2) has been developed to support more various modulation and coding schemes. While EGPRS supports only GMSK and 8-PSK, EGPRS2 additionally supports four modulation schemes: QPSK, 8-PSK, 16-QAM (16-Qaudrature Amplitude Modulation) and 32-QAM. EGPRS2 has two levels, EGPRS2-A and EGPRS2-B. EGPRS2-A supports GMSK, 8-PSK, 16-QAM and 32-QAM, and EGPRS2-B supports GMSK, QPSK, 16-QAM and 32-QAM. The modulation and coding scheme at each level in EGPRS2 is described in 3GPP TS 43.064 V7.6.0 (2007-08) "Technical Specification; GSM / EDGE Radio Access Network; General Packet Radio Service (GPRS); Overall description of the GPRS radio interface; Stage See Section 6.5.5.1.3 of "Release 7". EGPRS2 supports additional modulation schemes to enable high-speed data services using large data rates and high symbol rates.

A mobile station must be allocated an uplink packet resource in order to transmit packet data to a network. In GPRS / EGPRS / EGPRS2, it is said to establish an uplink TBF (Temporaty Block Flow). A control message sent by the mobile station to the network to establish a TBF is a packet channel request message.

EGPRS2 supports additional modulation schemes and also supports two levels of EGPRS2-A or EGPRS2-B, so that the network can inform the network of the features of EGPRS2 when requesting packet resources for faster packet resource allocation. There is a need.

An object of the present invention is to provide a method for receiving an uplink packet resource more quickly in an EGPRS2 system.

In one aspect, there is provided a method for transmitting a packet channel request message for requesting uplink resource allocation in an Enhanced General Packet Radio Service Phase 2 (EGPRS2) system. The method includes mapping different training sequences according to whether EGPRS2-A or EGPRS2-B is supported on an access burst, and sending a packet channel request message via the access burst.

By providing an EGPRS2 packet channel request message for EGPRS2, backward compatibility with existing packet channel request messages and EGPRS packet channel request messages can be maintained. Therefore, it is possible to provide a higher performance packet service to the mobile station.

1 is a block diagram illustrating a wireless communication system.

2 is a block diagram illustrating elements of a mobile station.

3 is an exemplary view showing a burst structure.

4 is a flowchart illustrating a single-phase connection process.

5 is a flowchart illustrating an abnormal access procedure.

1 is a block diagram illustrating a wireless communication system. This may be a wireless communication system supporting General Packet Radio Service (GPRS) / Enhanced General Packet Radio Service (EGPRS) / EGPRS2. Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, and the like.

Referring to FIG. 1, a mobile station (MS) 10 refers to communication equipment carried by a user, and includes a user equipment (UE), a user terminal (UT), a subscriber station (SS), and a wireless device (UE). Etc. may be called.

A base station (BS) 20 includes a base transceiver station (BTS) 22 and a base station controller (BSC) 24. The BTS 22 communicates with the mobile station 10 in one cell area through an air interface, and performs functions such as synchronization with the mobile station 10. The BSC 24 interfaces at least one BTS 22 with the Mobile Switching Center (MSC) 30.

The MSC 30 connects a heterogeneous network such as a Public Switching Telephone Network (PSTN) 65 or a Public Land Mobile Network (PLMN) to the base station 20 through a Gateway MSC (GMSC) 60. The VLR (Visitor Location Register) 40 stores temporary user data and contains information about roaming of all mobile stations 10 in the MSC 30 service area. The Home Location Register (HLR) 50 contains information about all subscribers in the home network. The Serving GPRS Support Node (SGSN) 70 is responsible for mobility management of subscribers. The Gateway GPRS Support Node (GGSN) routes the packet to the current location of the mobile station 10 and interfaces with an external packet data network, such as a Public Data Network (PDN).

2 is a block diagram illustrating elements of a mobile station. The mobile station 50 includes a processor 51, a memory 52, an RF unit 53, a display unit 54, and a user interface unit 55. . The memory 52 is connected with the processor 51 to store an operating system, an application, a training sequence, and the like. The display unit 54 displays various information of the mobile station, and may use well-known elements, such as a liquid crystal display (LCD) and organic light emitting diodes (OLED). The user interface unit 55 may be a combination of a well-known user interface such as a keypad or a touch screen. The RF unit 53 is connected to a processor and transmits and / or receives a radio signal.

The processor 51 is connected to the RF unit 53, requests uplink packet resources, and transmits packet data to the network using the allocated packet resources.

The mobile station may support General Packet Radio Service (GPRS), Enhanced General Packet Radio Service (EGPRS), and EGPRS2. EGPRS2 is supported by networks or mobile stations that support EGPRS. EGPRS2 has two levels, EGPRS2-A and EGPRS2-B. EGPRS2-A supports GMSK, 8-PSK, 16-QAM and 32-QAM, and EGPRS2-B supports GMSK, QPSK, 16-QAM and 32-QAM as well as high symbol rates.

Temporary Block Flow (TBF) is a logical connection provided by a Medium Access Control (MAC) entity to support one-way transmission of a Radio Link Control (RLC) Protocol Data Unit (PDU) on a basic physical subchannel. TBF is not provided in packet idle mode. In the packet idle mode, no radio resources on the packet data physical channel are allocated to the mobile station. At least one TBF is provided in a packet transfer mode. In the packet transfer mode, radio resources on at least one or more packet data physical channels for transmission of packet data are allocated to the mobile station. MAC-idle state refers to a MAC-control-entity to which no basic physical subchannel is assigned. Temporary Flow Identity (TFI) is assigned to each TBF by the network. The mobile assumes that the TFI value is unique among concurrent TBFs in the same direction (uplink or downlink) on all PDCHs (Packet Data Channels) commonly used for TBFs.

TBF for GPRS is called GPRS TBF, TBF for EGPRS is called EGPRS TBF, and TBF for EGPRS2 is called EGPRS2 TBF. The TBF for EGPRS2-A is called EGPRS2-A TBF, and the TBF for EGPRS2-B is called EGPRS2-B TBF.

3 is an exemplary view showing a burst structure. See also Sections 5.2.3 and 5.2.7 of 3GPP TS 45.002 V7.3.0 (2007-02) "Technical Specification Group GSM / EDGE; Radio Access Network; Multiplexing and multiple access on the radio path (Release 7)". Can be.

Referring to FIG. 3, a TDMA frame includes eight timeslots, with a burst representing the physical content of the timeslot. The normal burst includes a 26-bit training sequence and two 58-bit encrypted bits, and one normal burst can transmit 116-bit encoded bits. The training sequence, also called a synchronization sequence, is used for synchronization and channel estimation. The normal burst is mapped to a packet data traffic channel (PDTCH), a packet associated control channel (PACCH), a packet broadcast control channel (PBCCH), and the like.

The access burst includes a 41 bit training sequence and 36 bit encoded bits. An access burst is mapped to a random access channel (RACH), a packet random access channel (PRACH), an MBMS packet random access channel (MPRACH), and the like. The guard period of the access burst is longer than the guard period of the normal burst.

The extended tail bits of the access burst are defined as the following modulation bits.

(BN0, BN1, BN2 .. BN7) = (0, 0, 1, 1, 1, 0, 1, 0)

The tail bits of the access burst are defined by the following modulation bits.

(BN85, BN86, BN87) = (0, 0, 0)

There are three main types of training sequences. The basic training sequence TS0 is defined by the following modulation bits.

(BN8, BN9 .. BN48) = (0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0)

The first training sequence TS1 is defined as the following modulation bits.

(BN8, BN9 .. BN48) = (0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1)

The second training sequence TS2 is defined as the following modulation bits.

(BN8, BN9 .. BN48) = (1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1)

Now, a method of receiving an uplink packet resource in a GPRS / EGPRS / EGPRS2 system will be described.

To establish the uplink TBF, the mobile station sends a packet channel request message on the RACH or PRACH to the network. There are two processes for establishing uplink TBF: one phase access and two phase access. The mobile station uses 11 bits of information in the (EGPRS / EGPRS2) packet channel request message to indicate signaling or uplink TBF allocation for data transmission. At this time, it indicates whether to request TBF allocation through single phase connection or abnormal connection.

4 is a flowchart illustrating a single-phase connection process.

Referring to FIG. 4, the mobile station transmits a packet channel request message (EGPRS / EGPRS2) through the PRACH to the network to establish an uplink TBF (S210). (EGPRS / EGPRS2) The packet channel request message includes a connection type indicating a single phase connection or an abnormal connection and a parameter required for indicating a requesting radio resource. The packet channel request message is for establishing a GPRS TBF, the EGPRS packet channel request message is for establishing an EGPRS TBF, and the EGPRS2 packet channel request message is for establishing an EGPRS2 TBF.

The network informs the mobile station of a radio resource for the requested GPRS TBF / EGPRS TBF / EGPRS2 TBF through a packet uplink assignment message (S220).

Single-phase connection is supported only when the Radio Link Control (RLC) mode is Acknowledge mode. When the uplink TBF request of the mobile station also transmits a multi-slot class, uplink TBF allocation is possible without additional message between the mobile station and the network. This means that since the network knows the multi-slot class of the mobile station that requested the uplink TBF, multi-slot allocation is possible according to the configuration of the mobile station from the beginning. However, contention may occur at this time. Contention refers to multiple mobile stations transmitting (EGPRS / EGPRS2) packet channel request messages on the same PRACH or RACH, and uplink transmissions, even though they are not assigned TBF. Accordingly, for contention resolution, the mobile station transmits the TLLI (Temporary Logical Link Identifier), which is an identifier of the mobile station, through the PDTCH in a subsequent RLC data block. The mobile station says that contention resolution is completed when the same TLLI is included in the packet uplink ACK / NACK message received from the network. Then, the PDTCH transmits data without including the TLLI. If the mobile station receives a TLLI that is different from the TLLI it sends, it performs a TBF release due to contention resolution failure.

In other words, single-phase access requires fast channel allocation and is efficient when a good channel environment or a plurality of mobile stations are less likely to use the same PRACH or RACH, so that there is not much contention.

5 is a flowchart illustrating an abnormal access procedure.

Referring to FIG. 5, the mobile station transmits a packet channel request message (EGPRS / EGPRS2) through the PRACH to the network to establish an uplink TBF (S310). (EGPRS / EGPRS2) The packet channel request message includes a connection type indicating a single phase connection or an abnormal connection and a parameter required for indicating a requesting radio resource.

When the (EGPRS / EGPRS2) packet channel request message indicates an abnormal access request, the network allocates a single radio block on the uplink PDCH and informs the mobile station through the packet uplink assignment message (S320). The network may allocate a multi-block on the uplink PDCH when the EGPRS / EGPRS2 packet channel request message indicates an abnormal access request.

The mobile station receiving the packet uplink assignment message responds with a packet resource request message in the allocated radio block (S330).

The mobile station may inform the network of additional MS radio access capability information in the packet resource request message or through a separate message (S340). At this time, TLLI is also sent to the network.

The network notifies the mobile station of the allocated radio resource by sending a packet uplink assignment message on the PACCH (S350). The network sends a packet uplink assignment message including the TLLI onto the mobile station with reference to the access capability of the mobile station. The mobile station checks the TLLI in the packet uplink assignment message to determine whether contention resolution succeeds and, if successful, starts uplink TBF transmission.

The abnormal connection requires additional signaling with the network until the terminal transmits data as compared to the single-phase connection, but the network can receive more capability of the terminal than the single-phase connection because there is less resource waste due to contention resolution failure. Even if the terminal requests a single phase connection, the network may request the terminal to request an abnormal connection through a packet uplink assignment message.

(EGPRS / EGPRS2) The packet channel request message includes a connection type indicating a single phase connection or an abnormal connection and a parameter required for indicating a requesting radio resource. The mobile station may send a packet channel request message / EGPRS packet channel request message / EGPRS2 packet channel request message according to the TBF type it wishes to set up. The base station should be able to distinguish each packet channel request message among the packet channel request message / EGPRS packet channel request message / EGPRS2 packet channel request message that the mobile station arbitrarily transmits.

Packet channel request messages having an 11-bit format are shown in the following table. The packet channel request message is sent on the PRACH using an access burst. This includes 3GPP TS 44.060 V7.8.0 (2007-03) "Technical Specification Group GSM / EDGE Radio Access Network; General Packet Radio Service (GPRS); Mobile Station (MS)-Base Station System (BSS) interface; Radio Link Control / Medium Access Control (RLC / MAC) protocol (Release 7) ".

The 5-bit field 'MultislotClass' field indicates the mobile station's GPRS multislot class. Multislot classes are described in Table 10.5.146 of 3GPP TS 24.008 V8.0.0 (2007-12) "Technical Specification Group Core Network and Terminals; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 8)". Same as indicated in MS Radio Access Capability IE '. The 'Priority' field, which is a 2-bit field, indicates the requested radio weight (requested Radio Priority).

The EGPRS packet channel request message having the 11-bit format is shown in the following table. The packet channel request message is sent on a PRACH or RACH with an access burst. This is disclosed in section 11.2.5a of 3GPP TS 44.060 V7.8.0 (2007-03).

According to the current 3GPP TS 44.060 V7.8.0 (2007-03), the packet channel request message and the EGPRS packet channel request message are distinguished by different training sequences used for access bursts. The following table shows a packet channel request according to a training sequence.

That is, when the basic training sequence TS0 is detected, the network recognizes it as a packet channel request message, and when the first training sequence TS1 is detected, the network recognizes it as an EGPRS packet channel request message supporting 8PSK, and the second training sequence ( If TS2) is detected, 8PSK is recognized as an EGPRS packet channel request message which is not supported.

However, as EGPRS2 is introduced, a new packet channel request is required. That is, it is necessary to define the configuration of the EGPRS2 packet channel request message. This should provide backward compatibility with existing packet channel request messages and EGPRS packet channel request messages, while enabling easy detection. In addition, since EGPRS2 has two levels, EGPRS2-A and EGPRS2-B, it is necessary to distinguish them accordingly.

In one embodiment, an existing training sequence may be used to construct an EGPRS2 packet channel request message.

An example of the packet channel request according to the training sequence is shown in the following table.

The training sequences TS1 and TS2 for the existing EGPRS channel request message are also used for the EGPRS2 channel request, and include a field indicating whether EGPRS or EGPRS2 is supported in the EGPRS / EGPRS2 channel request message. The following table is an example of an EGPRS / EGPRS2 channel request message.

The 'EGPRS Support' field indicates that the mobile station supports EGPRS, the 'EGPRS2-A Support' field indicates that the mobile station supports EGPRS2-A, and the 'EGPRS2-B Support' field indicates that the mobile station supports EGPRS2-B. Instruct.

Alternatively, EGPRS2-A or EGPRS2-B may be informed according to the existing first training sequence TS1 and the second training sequence T2. An example of a packet channel request is shown in the following table.

The training sequences TS1 and TS2 for the existing EGPRS channel request message are also used for the EGPRS2 channel request, the first training sequence TS1 is used to indicate EGPRS2-A support, and the second training sequence TS2 is used. Used to indicate EGPRS2-B support. Unlike the Table 5, in the EGPSS / EGPRS2 channel request message, a field indicating only whether to support EGPRS2 may be included. The following table is an example of an EGPRS / EGPRS2 channel request message.

The 'EGPRS Support' field indicates that the mobile station supports EGPRS, and the 'EGPRS2 Support' field indicates that the mobile station supports EGPRS2. Therefore, if the 'EGPRS2 Support' field indicates EGPRS2, the network may distinguish EGPRS2-A or EGPRS2-B according to a training sequence.

In another embodiment, a new training sequence for an EGPRS2 packet channel request message can be defined.

A third training sequence TS3 for the EGPRS2 packet channel request message can be defined. An example of a packet channel request is shown in the following table.

At this time, the contents of the EGPRS2 packet channel request message are shown in the following table.

The 'EGPRS2-A Support' field indicates that the mobile station supports EGPRS2-A, and the 'EGPRS2-B Support' field indicates that the mobile station supports EGPRS2-B. A field indicating whether EGPRS2-A or EGPRS2-B is supported is added to an existing EGPRS packet channel request message.

Alternatively, EGPRS2-A or EGPRS2-B may be informed by defining two new training sequences, a third training sequence TS3 and a fourth training sequence T4. An example of a packet channel request is shown in the following table.

At this time, the EGPRS2 packet channel request message may have the same content as the existing EGPRS packet channel request message.

When using the training sequence for EGPRS2, the network can simply confirm whether EGPRS2-A or EGPRS2-B is supported by detecting only the training sequence for EGPRS2 through PRACH or RACH.

By providing an EGPRS2 packet channel request message for EGPRS2, backward compatibility with existing packet channel request messages and EGPRS packet channel request messages can be maintained. At this time, the mobile station can make one phase access to the EGPRS2-A and EGPRS2-B TBF requests using the EGPRS2 packet channel request message. Therefore, it is possible to provide a higher performance packet service to the mobile station.

Now we describe the training sequence for EGPRS2.

The new training sequence (TS3 and / or TS4) for the EGPRS2 packet channel request message is selected to have a low cross correlation and a high auto correlation compared to the existing training sequences TS0, TS1, TS2. .

In one embodiment, the training sequence for EGPRS2 may be defined by a cyclic shift of the existing training sequence. For example, the third training sequence TS3 and the fourth training sequence TS4 may be defined by cyclically shifting the first training sequence TS1 and the second training sequence TS2 by 10 bits. .

TS3 = (1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 0 , 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1)

TS4 = (1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1 , 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0)

In another embodiment, the training sequence for EGPRS2 may be defined by taking an inversion of some or all of the bit patterns of the existing training sequence. For example, the following third training sequence TS3 and fourth training sequence TS4 may be defined by inverting 10 bits before and after the first training sequence TS1 and the second training sequence TS2, respectively. have.

TS3 = (1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0 , 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0)

TS4 = (0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0 , 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0)

The cyclic shift value, the number of bits taking bit inversions, etc. are merely examples and do not limit the technical spirit of the present invention. Various methods can be used to define the bit pattern of the training sequence for EGPRS2, such as cyclic shift, bit inversion, or a combination thereof.

The invention can be implemented in hardware, software or a combination thereof. In hardware implementation, an application specific integrated circuit (ASIC), a digital signal processing (DSP), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, and a microprocessor are designed to perform the above functions. , Other electronic units, or a combination thereof. In the software implementation, the module may be implemented as a module that performs the above-described function. The software may be stored in a memory unit and executed by a processor. The memory unit or processor may employ various means well known to those skilled in the art.

As mentioned above, preferred embodiments of the present invention have been described in detail, but those skilled in the art to which the present invention pertains should understand the present invention without departing from the spirit and scope of the present invention as defined in the appended claims. It will be appreciated that various modifications or changes can be made. Accordingly, modifications to future embodiments of the present invention will not depart from the technology of the present invention.

Claims (4)

A method for transmitting a packet channel request message for requesting uplink resource allocation in an enhanced general packet radio service phase 2 (EGPRS2) system, Mapping different training sequences according to whether EGPRS2-A or EGPRS2-B is supported on the access burst; And Transmitting a packet channel request message via the access burst. The method of claim 1, And receiving a packet uplink assignment message in response to the packet channel request message. The method of claim 1, The packet channel request message is transmitted on a Packet Random Access Channel (PRACH) or a Random Access Channel (RACH). The method of claim 1, The EGPRS2-A supports Gaussian Minimum Shift Keying (GMSK), Phase Shift Keying (8-PSK), Qaudrature Amplitude Modulation (16-QAM), and 32-QAM, and the EGPRS2-B supports GMSK, QPSK, 16-QAM And 32-QAM.