KR100838534B1 - Resource Request and Allocation Method under Uplink Traffice Incidence in Mobile Communication System - Google Patents

Abstract

The present invention relates to a resource request method and an allocation method according to frequency of uplink traffic in a mobile communication system.

To this end, the present invention provides a method for requesting an uplink resource in a mobile communication system, the method comprising: determining whether the number of uplink traffic occurrences is greater than or equal to a preset reference value; Requesting the base station for a bandwidth request code and a periodic ranging code having a fixed code value when it is determined that the reference value is greater than or equal to the reference value; Receiving a fixed bandwidth request code and a fixed periodic ranging code from a base station; And performing ranging with the base station using the received fixed bandwidth request code or fixed periodic ranging code.

According to the present invention, when the subscriber station measures the frequency of uplink traffic and generates a lot of traffic, the subscriber station transmits a fixed bandwidth request code and a periodic ranging code to the base station and allocates a corresponding resource to the bandwidth request ranging or periodic ranging. By performing the collision without collision, it is possible to reduce the transmission delay of the uplink traffic and reduce the traffic transmission error due to the uplink transmission parameter adjustment delay.

Wireless Cellular Internet, Ranging, Bandwidth Request Ranging, Periodic Ranging

Description

Resource Request and Allocation Method under Uplink Traffice Incidence in Mobile Communication System}

1 is a signal flowchart illustrating a procedure of broadcasting system information in a wireless portable Internet system.

2 is a signal flow diagram illustrating a bandwidth request ranging procedure in a wireless portable Internet system.

3 is a flowchart illustrating a periodic ranging procedure in a wireless portable Internet system.

4 is a signal flowchart illustrating a ranging procedure according to an embodiment of the present invention.

5A and 5B are flowcharts illustrating a process of performing a ranging procedure in a subscriber station according to an embodiment of the present invention.

6 is a flowchart illustrating a process of performing a ranging procedure in a base station according to an embodiment of the present invention.

The present invention relates to a resource request method and an allocation method according to frequency of uplink traffic in a mobile communication system. More specifically, the present invention relates to a resource request method and an allocation method for bandwidth request ranging for uplink data transmission and periodic ranging for transmission parameter adjustment.

In the wireless portable Internet system, ranging is divided into initial ranging, periodic ranging (PR), bandwidth request ranging (BR), and handoff ranging.

Initial ranging and handoff ranging are used to adjust the transmit power, timing and frequency when the subscriber station first attempts to access the base station, and periodic ranging is appropriate for the channel environment that is changed by the subscriber station's movement. Used to adjust power, timing and frequency. And bandwidth request ranging is used to request uplink resources to the base station to transmit the uplink data when the uplink data occurs in the subscriber station.

1 is a signal flowchart illustrating a procedure of broadcasting system information in a wireless portable Internet system.

Referring to FIG. 1, in order to perform the above-mentioned ranging, an access pointer (AP) includes CDMA code information used for each ranging as system information in an uplink channel descriptor (UCD). Access Terminal) (S103).

In addition, the base station broadcasts the information on the uplink resources to be used by the subscriber station to transmit the CDMA code in the ranging process in the uplink map UL-MAP to the subscriber station (S105).

2 is a signal flow diagram illustrating a bandwidth request ranging procedure in a wireless portable Internet system.

Referring to FIG. 2, when uplink traffic occurs (S210), the subscriber station performs bandwidth request ranging to transmit data in uplink. In this case, the subscriber station selects any one of the BR (Bandwidth Request) codes included in the UCD received in the process of FIG. 1, and base station in a competitive manner selecting the BR code using resources allocated to UL-MAP. It transmits to (S220).

Subsequently, if the base station successfully receives the BR code from the subscriber station without collision, the base station uses the frame number, subchannel information, BR code number, and the subscriber station to request the BR code from the subscriber station. The bandwidth allocation information allocated to transmit the bandwidth request header) is included in the CDMA Allocation Information Element (CDMA_Allocation_IE) of the UL-MAP and broadcasted (S230).

Subsequently, the subscriber station determines whether the frame number, the subchannel information and the BR code number of the CDMA_Allocation_IE included in the UL-MAP received from the base station match the information transmitted by the subscriber station for the bandwidth request ranging, and is determined to match. In step S240, the BR header is transmitted to the base station using the allocated uplink resource. Here, the BR header includes resource information necessary for the terminal to transmit the uplink traffic.

Subsequently, when the base station receives the BR header from the subscriber station, the base station allocates the resource requested by the subscriber station and broadcasts the information on resource allocation in the UL-MAP (S250).

Subsequently, when the subscriber station receives the requested resource through the UL-MAP received from the base station, the subscriber station transmits uplink traffic through the UL-MAP (S260).

3 is a flowchart illustrating a periodic ranging procedure in a wireless portable Internet system.

Referring to FIG. 3, when the UE T4 indicating the ranging period expires (S311), the UE selects a random CDMA code for periodic ranging (PR) from the UCD to the base station in a competitive manner. It transmits (S313).

Subsequently, when the base station receives the CDMA code without collision, the base station measures timing, reception power, and frequency at the time of reception, calculates a necessary correction value, and broadcasts it to the subscriber station through RNG_RSP (S315).

Subsequently, the subscriber station determines whether the frame number, the subchannel number and the received PR code information included in the RNG_RSP match the information transmitted by the subscriber station to the base station. The uplink transmission parameter of the subscriber station is adjusted using the value (S317), and the timer T4 is reset (S319).

This process is performed periodically whenever the timer T4 expires.

In the bandwidth request ranging and periodic ranging performed between the subscriber station and the base station, code transmission is performed in a competitive manner. If a collision occurs in the bandwidth request ranging performed in this contention scheme, the subscriber station needs to retransmit the BW Code, which causes a problem of increased traffic transmission delay.

In addition, as in the bandwidth request ranging, if a collision occurs in the periodic ranging, since the subscriber station retransmits the PR code to the base station, the time required for adjusting the uplink transmission parameter in the subscriber station is increased, thereby transmitting. A problem that an error occurrence probability of uplink data increases.

In addition, since the periodic ranging period is periodically performed between the subscriber station and the base station regardless of the generation of uplink traffic of the subscriber station, if the period is large, the adjustment period of the uplink transmission parameter is long, so There is a problem that the probability of an error increases.

On the contrary, if the ranging period is small, there is a problem that waste of downlink resources for RNG_RSP transmission occurs.

In order to solve such a problem, a method of eliminating traffic transmission delays and adjustment delays of transmission parameters due to collisions occurring during bandwidth request ranging and periodic ranging is provided, and a method of reducing an error occurrence probability is provided.

According to an aspect of the present invention, there is provided a method for requesting an uplink resource in a mobile communication system, the method comprising: determining whether an uplink traffic occurrence count is greater than or equal to a preset reference value; Requesting a bandwidth request code and a periodic ranging code having a fixed code value to the base station when it is determined that the reference value is greater than or equal to the reference value; Receiving, from the base station, a fixed bandwidth request code and a fixed periodic ranging code, wherein the fixed bandwidth request code and the fixed periodic ranging code are codes that match a preset resource, respectively; And performing ranging with the base station using the received fixed bandwidth request code or fixed periodic ranging code.

A method for allocating an uplink resource in a mobile communication system, the method comprising: receiving a fixed bandwidth request code and a fixed periodic ranging code having a fixed code value from a subscriber station; And a fixed bandwidth request code, a fixed periodic ranging code, wherein the fixed bandwidth request code and the fixed periodic ranging code are respectively matched to a preset resource and the fixed bandwidth request code and the fixed periodic ranging code. Transmitting a transmission period to the subscriber station; Checking a type of a code for requesting resource allocation received from the subscriber station; And allocating a resource corresponding to the identified code type to the subscriber station.

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, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, this means that it may further include other components, except to exclude other components unless otherwise stated.

4 is a signal flowchart illustrating a ranging procedure according to an embodiment of the present invention. Hereinafter, the ranging procedure according to an embodiment of the present invention will be described with reference to FIG. 4. Here, the detailed ranging method of the subscriber station and the base station for convenience of description will be described in detail with the configuration below.

First, the subscriber station measures the frequency of the data traffic to be transmitted in the uplink (S410), and determines whether the measured traffic occurrence frequency is higher than a predetermined value (S420).

If it is determined in step S420 that the frequency of traffic occurrence is high, the subscriber station determines a fixed bandwidth request code (hereinafter referred to as 'BR Code') and a fixed periodic ranging code (Periodic) previously set by the subscriber station. In order to receive the Ranging Code, hereinafter referred to as 'PR Code', Fixed_Code_Alloc_Req is transmitted to the base station (S421).

Subsequently, the base station receiving the Fixed_Code_Alloc_Req transmits the Fixed_Code_Alloc_Rsp including the fixed BR Code, the fixed PR Code, and the period information for transmitting the codes to the UE (S423).

The subscriber station checks whether data traffic to be transmitted through the uplink is generated at regular intervals using period information allocated to the base station. When traffic occurs, the subscriber station requests uplink resources without collision by using the assigned fixed BR code, and performs periodic ranging without collision by using the fixed PR code allocated for periodic ranging when no traffic occurs. (S425).

Subsequently, the subscriber station measures the frequency of traffic occurrence (S440), and compares the occurrence frequency with a preset value to determine whether the traffic is low or high (S450).

If it is determined in step S450 that the occurrence frequency is low, the subscriber station transmits Fixed_Code_Release_Req to release the allocated fixed BR code, fixed PR code and period (S451), and the base station transmits the assigned code and period in response thereto. Release and the fixed_Code_Release_RSP, which is a release response message, is transmitted to the terminal (S453).

5A and 5B are flowcharts illustrating a process of performing a ranging procedure in a subscriber station according to an embodiment of the present invention. Hereinafter, the subscriber station according to an embodiment of the present invention will be described with reference to FIGS. 5a and 5b. The ranging procedure will be described.

First, the subscriber station sets a timer Ts to measure the frequency of uplink traffic generation, and sets K indicating the frequency of occurrence to '0' (S500).

Subsequently, the subscriber station determines whether the timer Ts expires (S501), and if it is determined in step S501 that Ts has not expired, the subscriber station determines whether uplink traffic occurs (S502).

If it is determined in step S502 that uplink traffic occurs during Ts, the subscriber station selects an arbitrary BR code and transmits it to the base station and performs bandwidth request ranging in a competitive manner (S503).

If it is determined in step S502 that no uplink traffic occurs during Ts, the flow proceeds to step S501.

Subsequently, the subscriber station transmits the traffic to the base station using the resources allocated from the base station through the bandwidth request ranging (S504), and resets the timer Ts to increase the K representing the traffic occurrence frequency by '1' (S505).

If it is determined in step S501 that the timer Ts has expired, the subscriber station resets the timer Ts while decreasing the K representing the frequency of traffic generation by '1' (S507).

Subsequently, the subscriber station determines whether the traffic occurrence frequency K is greater than a preset maximum value Kmax (S508), and if it is determined in step S508 that the traffic occurrence frequency K is greater than Kmax, the subscriber station is fixed to the base station with a fixed BR code and a fixed PR code. To transmit the request, Fixed_Code_Alloc_Req is transmitted (S510).

If it is determined in step S508 that the traffic occurrence frequency K is smaller than Kmax, the traffic is reset so that K is not smaller than 0 (S509) and the above process is repeated.

Subsequently, the subscriber station receives Fixed_Code_Alloc_Rsp from the base station in response to the transmitted Fixed_Code_Alloc_Req (S511), sets Tp, which is a code transmission period included in the received Fixed_Code_Alloc_Rsp, and sets L, which indicates the frequency of traffic, to a preset maximum value Lmax. It is set (S512).

Subsequently, when the Tp expires (S513), the subscriber station determines whether uplink traffic has occurred (S514).

If it is determined in step S514 that the uplink traffic occurs, the subscriber station performs the bandwidth request ranging without collision using the fixed BR code allocated from the base station (S515), and uses the allocated resources to perform uplink traffic. In step S516, L representing the frequency of traffic occurrence is increased to '1' and Tp is reset (S517).

If it is determined in step S514 that no uplink traffic occurs, the subscriber station performs periodic ranging without collision by using the allocated fixed PR code (S518), and resets Tp while reducing L to '1' ( S519).

Subsequently, when the subscriber station receives RNG_RSP including timing, power, and frequency, which are uplink transmission parameters adjusted by the base station while receiving Fixed_Code_Alloc_Rsp from the base station in step S511, the received terminal adjusts uplink transmission parameters (S520). ).

Subsequently, the subscriber station determines whether L representing the frequency of traffic generation is greater than zero (S521), and if it is determined in step S521 that L is not greater than zero, the subscriber station determines that the frequency of traffic occurrence is low and allocates a fixed BR code and a fixed frequency. The Fixed_Code_Release_Req requesting the release of the PR code is transmitted to the base station (S522), and in response thereto, the Fixed_Code_Release_Rsp is received from the base station (S523), and the process proceeds to step S501 to repeat the above steps.

Further, if it is determined in step S521 that L is greater than zero, the process proceeds to step S513 and the above steps are repeated.

Through the above-described process, if the traffic occurrence frequency is large, the subscriber station can perform code transmission without collision by receiving a fixed BR code and a fixed PR code from the base station and performing bandwidth request ranging and periodic ranging.

In addition, the subscriber station transmits a fixed BR code or a fixed PR code to the base station for each code transmission period Tp to receive and adjust the uplink transmission parameter adjusted by the base station, thereby reducing the error probability caused by the transmission parameter error.

6 is a flowchart illustrating a process of performing a ranging procedure in a base station according to an embodiment of the present invention. Hereinafter, a ranging procedure in a subscriber station according to an embodiment of the present invention will be described with reference to FIG. 6. Shall be.

First, when the base station receives the fixed BR code and the fixed_Code_Alloc_Req requesting the fixed PR code assignment from the subscriber station (S610), the base station allocates the fixed BR code, the fixed PR code and the code transmission period Tp requested by the subscriber station (S620). In operation S630, Fixed_Code_Alloc_Rsp including information on the allocated BR Code, PR Code, and code transmission period Tp is transmitted to the subscriber station.

Subsequently, the base station determines whether Fixed_Code_Release_Req is received requesting release of the allocated BR Code and PR Code from the subscriber station (S640).

If it is determined in step S640 that Fixed_Code_Release_Req is not received, the base station determines whether a fixed BR code or a fixed PR code allocated by the base station is received from the subscriber station (S650).

Subsequently, upon receiving the allocated fixed BR code, the base station performs a resource allocation process according to the bandwidth request ranging procedure (S653).

Subsequently, when the base station determines that adjustment of timing, power, and frequency values, which are measured uplink transmission parameters, is required when receiving the fixed BR code (S660), the base station transmits RNG_RSP including necessary parameter adjustment values (S670).

If the base station receives the fixed PR code and determines that adjustment of the transmission parameter is necessary according to the periodic ranging procedure (S660), the base station transmits an RNG_RSP including the necessary parameter adjustment value to the terminal (S670).

If the base station receives Fixed_Code_Release_Req from the terminal in step S640, the base station releases the assigned fixed BR and fixed PR code (S643), and transmits Fixed_Code_Release_Rsp to the terminal (S645).

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

As described above, according to the present invention, when a subscriber station measures a frequency of uplink traffic and transmits a lot of traffic, the subscriber station transmits a fixed bandwidth request code and a periodic ranging code to the base station and receives a corresponding resource to allocate a bandwidth request lane. By performing the charging or periodic ranging without collision, it is possible to reduce the transmission delay of uplink traffic and to reduce the traffic transmission error due to the uplink transmission parameter adjustment delay.

Claims (12)

In the method for requesting an uplink resource in a mobile communication system, Determining whether the number of uplink traffic occurrences is greater than or equal to a preset reference value; Requesting a bandwidth request code and a periodic ranging code having a fixed code value to the base station when it is determined that the reference value is greater than or equal to the reference value; Receiving, from the base station, a fixed bandwidth request code and a fixed periodic ranging code, wherein the fixed bandwidth request code and the fixed periodic ranging code are codes that match a preset resource, respectively; And Ranging with the base station using the received fixed bandwidth request code or fixed periodic ranging code Resource request method comprising a. The method of claim 1, Before the judging step Initiating an uplink frequency measurement timer and the number of uplink traffic occurrences; Determining whether the uplink frequency measuring timer has expired; Determining whether uplink traffic occurs when it is determined in the step of determining whether it has expired; If it is determined that the uplink traffic occurs in the step of determining whether uplink traffic occurs, transmitting uplink traffic through the bandwidth request ranging with the base station; And Receiving the fixed bandwidth request code, the fixed periodic ranging code, and the transmission period of the fixed bandwidth request code and the fixed periodic ranging code from the base station Resource request method further comprising. The method of claim 2, If it is determined that it has expired in the step of determining whether it has expired, initializing the uplink frequency generating timer and reducing the number of uplink traffic occurrences; Resource request method further comprising. The method of claim 2, Performing the ranging is Initializing the transmission period and setting a frequency of traffic generation to a preset maximum value; Determining whether additional uplink traffic occurs when the transmission period has expired; If it is determined that the additional uplink traffic has occurred in the step of determining whether the additional uplink traffic is generated, performing bandwidth request ranging with the base station using the fixed bandwidth request code and corresponding to the fixed bandwidth request code Receiving a resource; Transmitting the additional uplink traffic using the allocated resource; Increasing the frequency of traffic occurrence and initializing the transmission period; Determining whether the traffic occurrence frequency is less than or equal to a preset reference value; And If it is determined that the reference value is less than the reference value, requesting the base station to release the bandwidth request code and the periodic ranging code from the base station. Resource request method further comprising. The method of claim 4, wherein Between the initializing and determining whether or not below the reference value If the base station receives timing, power, and frequency information which is the uplink transmission parameter reset by the base station, applying the reset uplink transmission parameter; Resource request method further comprising. The method of claim 2, Performing the ranging is Initializing the transmission period and setting a frequency of traffic generation to a preset maximum value; Determining whether additional uplink traffic occurs when the transmission period has expired; In the determining whether the additional uplink traffic is generated, performing periodic ranging with the base station using the fixed periodic ranging code when it is determined that the additional uplink traffic does not occur; And Reducing the frequency of traffic occurrence and initializing the transmission period Resource request method further comprising. In the method for allocating uplink resources in a mobile communication system, Receiving a fixed bandwidth request code and a fixed periodic ranging code having a fixed code value from the subscriber station; And Fixed bandwidth request code, fixed periodic ranging code, where the fixed bandwidth request code and fixed periodic ranging code are matched with preset resources, respectively, and transmission of the fixed bandwidth request code and the fixed periodic ranging code Transmitting a period to the subscriber station; Checking a type of a code for requesting resource allocation received from the subscriber station; And Allocating a resource corresponding to the identified code type to the subscriber station; Resource allocation method comprising a. The method of claim 7, wherein The assigning step And when the type of the identified code is the fixed bandwidth request code, allocating a resource corresponding to the fixed bandwidth request code to the subscriber station through a bandwidth request ranging. The method of claim 7, wherein After the assigning step Determining whether adjustment of an uplink transmission parameter of the subscriber station is necessary and transmitting timing, power, and frequency information, which is a reset uplink transmission parameter, if determined to be necessary, to the subscriber station; Resource allocation method further comprising. The method of claim 7, wherein Between the sending step and the checking step Determining whether there is a resource allocation request for requesting the allocation of the fixed bandwidth request code and the fixed periodic ranging code from the subscriber station; Resource allocation method further comprising. The method of claim 10, In the step of determining whether there is a resource allocation request, And if it is determined that there is no resource allocation request, performing the checking. The method of claim 10, In the step of determining whether there is a resource allocation request, Releasing the fixed bandwidth request code and the fixed periodic ranging code allocation requested by the subscriber station when it is determined that the resource allocation release request has been made; Resource allocation method further comprising.

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