KR20050063601A - The method of changing high-speed burst profile of portable internet system - Google Patents

Abstract

The present invention efficiently uses a DBPC-REQ message that is used when a mobile terminal connected to a high speed portable internet (HPi) system is deactivated for some time on the uplink and detects fading on the downlink. In this paper, we propose uplink bandwidth allocation scheme by allocating DBPC-REQ dedicated CDMA ranging code, and find a point of time to efficiently process DBPC-REQ received by the proposed access scheme and change requested DIUC. It is suggested.

The access point (AP) of the high-speed portable Internet system is a system with enhanced mobility than the existing broadband wireless access (BWA) system. You need an additional message to report. In this patent, a DBPC-REQ message used in a high-speed portable Internet system is a message in which a mobile terminal reports a change of a wireless channel to an AP. However, since the high speed portable Internet system does not have a separate channel for uplink used in the existing mobile communication system, when uplink traffic exists in a CID (Connection ID) used by a corresponding terminal in order to transmit a message upward, A method of transmitting concatenated uplink allocation message in traffic data and transmitting uplink allocation message and using bandwidth allocation request using code in CDMA should be used. Among the above-mentioned methods, the CDMA code usage method used when there is no traffic may fail in ranging competition when using the same code as the initial code ranging code. In this case, the subscriber may experience a disconnection but not handover. In order to solve this problem, the present invention assigns a separate CDMA code for DBPC-REQ, which is a downlink burst profile update request message requested by a mobile subscriber in a call, so that the downlink burst profile update can be performed quickly without feeling user disconnection. Is proposing.

Description

The method of changing high-speed burst profile of portable internet system using dedicated CDM code assignment

The present invention relates to a CDMA ranging code allocation method for DBPC to reduce connection disconnection by processing DBPC-REQ at high speed in a high speed portable Internet system and to a synchronization for changing LESS BURST DIUC between AT and ATS. CDMA code allocation method for DBPC-REQ and DBPC-REQ message processing method.

Conventional OFDM wireless communication systems mainly propose algorithms that minimize the interference between base stations by differently assigning ranging codes used by each base station. In general, when the ranging codes are used in all base stations, interference is increased. It is natural that such an algorithm is needed.

Such a ranging code allocation algorithm can reduce interference between base stations by allocating codes used by each base station, but since the number of codes allocated to each base station itself is reduced, it is inefficient when multiple subscribers simultaneously request access. In addition, the burst profile request message of the mobile terminal connecting with the mobile terminal requesting the initial ranging function contends together so that when the mobile terminal attempts connection connection, the down burst profile of the mobile subscriber in service is not changed in time. The problem is that the current connection is disconnected.

In order to solve the above problem, the present invention does not use the CDMA codes used in the high-speed portable Internet system in all cases, but instead uses a dedicated CDMA code for processing a message requesting the mobile terminal in service to change the downlink burst profile. By allocating the network, the traffic of the currently serving mobile terminal can be reduced as much as possible.

If the requesting DBPC-REQ is LESS ROBUST, the DBPC_RSP message is sent before changing the DIUC if LESS ROBUST is requested before the DIUC changed by the DBPC-REQ message is changed. After the transmission is confirmed, the algorithm for changing the required DIUC can be proposed to efficiently handle LESS ROBUST.

When the mobile station is inactive for some time on the uplink and detects fading on the downlink, band allocation is performed using the DBPC dedicated CDMA code proposed by the present invention to find the best DIUC for the current radio channel and transmit a DBPC-REQ message. By requesting, it can overcome the situation of call disconnection when DBPC-REQ fails by competing with initial ranging or traffic allocation request message.

However, because the number of CDAM codes is limited to 48, the number of available ranging codes is divided by a fixed number, and there is a high probability that the ranging codes will collide and fail if there is no traffic connection during cell initialization.

In order to solve this problem, the present patent enables active allocation of the CDMA code to be used as the number of traffic connections of the current AP is large and small, so that the initializing of the cell is more difficult than when using the conventional fixed CDMA code count. Initial ranging is more efficient when there is less traffic connection. When there are a lot of traffic connection users, more burst profile CDMA codes are assigned to manage the code so that bursted profile changes can be performed more quickly. It can also increase the success rate and reduce the loss of already connected traffic connections.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification.

A detailed description will be given of a method for performing an efficient ranging method in the high-speed portable Internet system of the present invention having the features as described above.

1 is a structural diagram of a portable Internet system to which the present invention is applied. The mobile Internet system is largely an Access Terminal (AT-110) which is a portable Internet terminal, an Access Point (AP-120) that performs a base station function, a packet access routing function that performs a packet access routing function, and an external agent function of Mobile IP. (PAR 130). The structure of the AP in which the present invention is carried out includes an ACS (Access Controller Subsystem) system for performing user management and cell management, a BaseBand Subsystem (121) subsystem for performing a wireless section transmission and reception function, a traffic processing and a radio link. It is composed of an Access Traffic Subsystem (ATS) 122 performing a transmission / reception control function. FIG. 1 is a diagram illustrating an embodiment of the structure.

2 is a diagram illustrating in detail the software structure of the ATS and ACS to which the present patent is applied among the Hpi structures described in FIG. 1 to which the present invention is applied. The AP structure is largely composed of an ACS (220: Accesess Controller Subsystem) that manages the resources of each AT and controls the base station, and an ATS (Access Traffic Subsystem) 210 that processes the traffic between the base station and the terminal. In particular, the ATS to which the function of the present patent is processed includes a scheduling block (PSCB) (Packet Scheduling Block: 213), a radio link control block (RNGB) (Ranging Control Block: 211), an ARQB (Automatic Repeat Request Block: 216) for controlling retransmission, Manages Packet Handling Block (PHDB), a block that constitutes MAC PDU to be transmitted in radio section, Packet Classification Block (217) that performs packet classification function and CID mapping function of received packet, and DSP and interface It consists of seven software blocks such as DSP Interface Control Block (DICB).

3 shows an HPi frame structure to which the present invention is applied. The structure of this frame is a DL Preamble (310) to inform the start of the HPi frame (310), the System Information Channel is a part of the system information down (320), DL-MAP that informs the terminal of the location of traffic and message information for the uplink and downlink / UL-MAP 330, DL Burst area 340 in which actual data is transmitted, UL Burst area 350 in which uplink data is transmitted from the terminal to the AP, and Ranging area 360 in which the terminal accesses with CDMA code. ) In this frame structure, in this patent, the CDMA code area that carries the ranging information is currently divided into three types, and the DBPC dedicated code dedicated to the DBPC-REQ which actively changes the burst profile of the traffic performed due to the radio characteristics is allocated. Let's say it.

4 shows a CDMA code allocation method used in HPi to which the present invention is applied. Three types of CDMA codes for ranging used in the current HPI system, and a table of static division divided by the range and number of DBPC-required CDMAs proposed in the present patent. In this table, the initial CDMA code 410 used when the terminal requests initial ranging, the periodic CDMA code 420 at which the terminal periodically reports its current state, and the terminal to send data upward. It is currently configured with a band allocation CDMA code 430 that requires a band allocation to the scheduler. The present patent intends to add one more type of DBPC-required CDMA code 440 required to report the change of the wireless environment of the terminal to the AP quickly.

5 shows a message sequence chart (MSC) for processing a DBPC-REQ function required by the AT in ATS. When the terminal changes its downlink burst profile and transmits a DBPC-REQ message to the ATS, the terminal transmits the DBPC ranging code to the RNGB of the ATS using the DBPC ranging code proposed in the present patent (510). The ranging code received in the above 510 is processed first and the UL-MAP request message for the DBPC-REQ is transmitted from the RNGB to the PSCB to the corresponding UE (520). Upon receiving this message, the PSCB transmits DBPC-REQ message allocation information to UL-MAP information of the next frame to the AT (530). The terminal receiving the DBPC-REQ message through the 530 transmits the DBPC-REQ message in the form of a message through the UL-BURST region, and the TRMB of the ATS sends the msgDbpcReqInd_id message to the RNGB of the terminal (550). The RNGB receives this message, changes the DIUC requested by DBPC-REQ, and transmits a DBPC-RSP message (560).

FIG. 6 is a flowchart illustrating a method of sending a change message to an AT through UCD when a reallocated CODE_COUNT_INDEX is changed by reassigning CODE_COUNT_INDEX with a traffic connection currently being performed in the resource allocation block of the ACS. The ACS receives a new connection request message from the ATS (610). A new connection is established with the message received at 610 (620). If a new connection is established by 620, the fnCdmaCodeAssign function is performed (630). In the above step 630, the value obtained by subtracting I from MAX_TRAFFIC_INDEX is allocated as K to reassign CDMA code (631). Compare the current trafficAtCount with less than or equal to MAX_TRAFFIC_CON_COUNT / k with the assigned K (632). If the value compared at 632 is true, I is returned (633). If 632 is false, increase I and perform 631 again. The I value determined in 631 to 633 is compared with OLD_CODE_COUNT_INDEX (634). If the result performed at 634 is true, each code number is set with NEW_CODE_COUNT_INDEX and a UCD change message is sent to the ATS (635). If 634 is false, do not perform 635.

FIG. 7: A table showing the CODE_COUNT_INDEX relationship with the currently connected traffic connection required in FIG. 6. If the number of users is small, CODE_COUNT_INDEX is 1 (700), and as the number of users increases, CODE_COUNT_INDEX increases (710,720).

FIG. 8 is a table showing efficient number of CDMA codes with CODE_COUNT_INDEX set by FIG. 6 and FIG. The total number of CDMA codes used in HPi system is 48 (810). Of these 48 items, BASIC_CDMA_CODE_COUNT is basically assigned to 4 for each type (820). The remaining number of codes allocated from 810 to 820 is allocated to MAX_ASSIGN_CDMA_ CODE_COUNT (MACCC) (830). Calculate the required CODE COUNT in each part using MACCC and CODE_COUNT_INDEX calculated in 830 (840 ~ 870)

9 is a flowchart of processing a DBPC-REQ message in ATS. When the ranging processing block receives the DBPC-REQ message through TRMB, the corresponding AT DIUC in the current ATS is found and stored in currentDiuc (910). The DIUC of the received DBPC-REQ message is found and stored in newDiuc (911). Based on the values stored in FIGS. 910 to 911, currentFCT and nweFCT are found from burstProfile information (912). If currentFCT is larger than NewFCT and currentFCT, the value becomes MORE_BURST_TYPE, and the DIUC received from DBPC-REQ is stored in the AT information field in ATS, and a DBPC-RSP message is generated (914). The DBPC-RSP MAC message generated at 914 is sent to the PCFB with rngbId set to 1 (915). If the value determined in step 913 is LESS_BURST_TYPE, the DBPC information is stored in rngbInfo_type (916) and a message is generated to send data to the PCFB with the corresponding rngbId. If BURST_TYPE is LESS_BURST_TYPE, PCFB sends DBPC_RSP message and calls libPcfbToRngbInd function to change the DIUC of traffic (920 ~ 923).

Although the preferred embodiment of the present invention has been described in detail above, the present invention is not limited thereto, and various other changes and modifications are possible.

As described above, the present invention provides a DBPC-REQ message that is used when a mobile terminal connected to a high speed portable internet (HPi) system is deactivated for some time on the uplink and detects fading on the downlink. Handover by allocating DBPC-REQ dedicated CDMA ranging code necessary for efficient use and suggesting uplink bandwidth allocation method, processing DBPC-REQ received by the proposed access method efficiently and changing requested DIUC In addition, even in a poor wireless environment, there is an effect of preventing the communication is cut off.

1 is a block diagram of a high-speed portable Internet network to which the present invention is applied

Fig. 2: Software structure diagram of ATS and ACS to which the present invention is applied

Figure 3: HPi frame structure to which the present invention is applied

4 is a CDMA code allocation method used in HPi to which the present invention is applied

Figure 5: MSC (Message Sequence Chart) in ATS for DBPC-REQ Function Required by AT

Figure 6: A change message is sent to AT through UCD by allocating CODE_COUNT_INDEX with the traffic connection currently being performed in the resource allocation block of ACS.

Figure 7: A table showing the CODE_COUNT_INDEX relationship with the traffic connections currently in service required in Figure 6.

Figure 8: Table showing the number of effective CDMA codes with CODE_COUNT_INDEX set by Figures 6 and 7

Figure 9: Flowchart of processing DBPC-REQ message in ATS

Claims (3)

Setting CODE_COUNT_INDEX according to user capacity for changing burst profile of traffic in high-speed portable Internet system; Calculating a CODE_COUNT that can use each CDOE by the above step; Step 3 of broadcasting the system information changed by step 2 to the AT Fast down burst profile change method using a dedicated CDMA code assignment comprising a. The method of claim 1, Receiving a DBPC-REQ message, TRMB calls the RNGB function for DBPC-REQ processing: Step 2: determining whether the downlink burst profile requested by DBPC-REQ received by step 1 is (DIUC) MORE BURST or LESS BURST: A method of changing a fast downlink burst profile using dedicated CDMA code allocation for more BURST processing, including three steps of transmitting and processing DBPC-RSP when the BURST TYPE determined by step 2 is MORE BURST. The method of claim 2, Step 1 of transmitting the DBPC-RSP message to the PCFB when the BURST TYPE determined in the second step is LESS ROBUST: Step 2: Sending a response message to the RNGB when the PCFB sends a response message by the PSCB according to step 1: A method of changing a fast downlink burst profile using dedicated CDMA code allocation that processes LESS BURST, including step 3 of changing RNGB to a new DIUC after confirming that DBPC-RSP is transmitted by step 2.