KR20010009345A - Method of asymmetric channel rate modification by buffer and time control for data transmission in wireless system - Google Patents

Abstract

PURPOSE: A method for modifying an asymmetric channel using a buffer and a timer management in a wireless system, is provided to use the buffer and a timer control for effectively using wireless resources between a subscriber and a base station, and to adaptively convert band widths of a upper and a lower channel, so as to effectively use the wireless channel. CONSTITUTION: A subscriber match checks a state of a terminal transmitting buffer(401). If data buffered to a transmission buffer is smaller than a determined lower reference value and a sustained time elapses for a determined time, the subscriber match performs a bearer channel modification(BCM) for reducing a bearer speed of a upper link(408). If the data buffered to the transmission buffer is larger than a determined upper reference value and the sustained time elapses for a determined time, the subscriber match performs the BCM for increasing the bearer speed of the upper link(413). If the data buffered to the transmission buffer is larger than the determined lower reference value and the data is smaller than the determined upper reference value, the subscriber match maintains a current state(409).

Description

Asymmetric channel conversion method using buffer and timer management in wireless system {Method of asymmetric channel rate modification by buffer and time control for data transmission in wireless system}

The present invention relates to a technology for providing a data service in a wireless communication network environment, and more particularly, using a buffer and time control in data transmission in a mobile communication and wireless subscriber network (WLL) system using W-CDMA or CDMA. It relates to a method of asymmetrically converting the speed of the up and down channels.

In a wireless communication network, a transmission bandwidth is conventionally determined by a parameter value set at a call set-up, rather than a speed of a channel for data communication depending on the amount of data to be transmitted. However, no matter how much bandwidth is allocated in the wireless section, which is part of the transmission path, the rate at which the actual data is transmitted to the subscriber often changes due to the server's circumstances in the network. In other words, when the number of terminals accessing the same server on the Internet increases, the speed provided by the Internet may be lower than the initially set wireless bandwidth. In this case, the difference is inefficient because data transmission is filled with blank data. have.

In contrast, most of the data used on the Internet is data transmitted to subscribers, and the amount of data transmitted from subscribers is often very small. In other words, subscribers often download data rather than upload data when they access the Internet. Even when the pointer is clicked to view the next frame linked from the HTML file, which is web data, the uploaded data is about 50-100 bytes long. It is only Therefore, although there is a difference in data transmission amount between the uplink channel, which is a path from the subscriber to the network for upload, and the downlink channel, which is a communication path from the network to the subscriber, for download, the uplink and downlink channels have the same speed. There is a problem that radio resources are inefficiently used.

Accordingly, the present invention provides a buffer in a wireless system capable of converting bandwidth of upstream and downstream channels according to data amount using buffer and timer control to efficiently use radio resources between subscriber and base station in W-CDMA wireless communication network. And an asymmetric channel conversion method using timer management.

In order to achieve the above object, a method of converting a speed of an uplink of the present invention includes: checking a state of a terminal transmission buffer in a subscriber matching device; Performing channel change to reduce the bearer speed of the uplink when the data buffered in the transmission result is less than a predetermined lower limit reference value and the duration thereof passes a predetermined time; Performing a channel change to increase the bearer speed of the uplink when the data buffered in the transmission result is greater than a predetermined upper limit reference value and the duration of the test result exceeds a predetermined time; And maintaining the present state when the data buffered in the test result transmission buffer is larger than a predetermined lower limit reference value and smaller than an upper limit reference value.

In addition, the method for converting the speed of the downlink of the present invention in order to achieve the above object, the step of checking the state of the transmission buffer of the network side; Performing channel change to reduce the bearer speed of the downlink when the data buffered in the transmission result is less than a predetermined lower limit reference value, and the duration thereof passes a predetermined time; Performing a channel change to increase the bearer speed of the downlink when the data buffered in the transmission result is greater than a predetermined upper limit reference value and the duration thereof passes a predetermined time; And maintaining the present state when the data buffered in the test result transmission buffer is larger than a predetermined lower limit reference value and smaller than an upper limit reference value.

1 is an example of a wireless system suitable for application of the present invention,

2 is a signal flow diagram illustrating a process of converting a rate of an uplink channel according to the present invention;

3 is a signal flow diagram illustrating a process of converting a rate of a downlink channel according to the present invention;

4 is a flowchart illustrating a process of converting a rate of an uplink channel in a terminal according to the present invention;

5 is a flowchart illustrating a process of converting a rate of a downlink channel in a terminal according to the present invention.

* Explanation of symbols for main parts of the drawings

102: personal computer 110: subscriber access unit (RIU)

112a: POTS section 112b: BRI section

112c: data portion 114: digital modulation and demodulation portion

116: RF unit 120: base station

130: base station controller 140: IWF

150: Internet

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 illustrates a configuration of a wireless subscriber network (WLL) as an example of a typical wireless system suitable for application of the present invention. The wireless subscriber network to which the present invention can be applied includes a subscriber access device (RIU) 110, a base station (RP: 120), a base station controller (RPC: 130), and a data service processor (IWF) to which a personal computer (PC) 102 is connected. Inter Working Function 140 and the Internet 150.

Referring to Figure 1, the subscriber access device 110 is referred to as "Radio Interface Unit (RIU)", POTS unit 112a, BRI unit 112b, DATA unit 112c, digital modulation and demodulation unit 114, RF Section 116. An ordinary telephone is connected to the POTS (Plain Old Telephone Service) unit 112a of the subscriber access device, an ISDN terminal is connected to the BRI unit 112b by an RJ-45 method, and an RS-232C method to the DATA unit 112c. The personal computer 102 is connected. The subscriber access device 110 has a bi-directional communication function for connecting the subscriber device with the base station 120 in a W-CDMA manner.

The base station 120 is referred to as a "Radio Port (RP)", and is connected to the subscriber access device 110 in a wireless subscriber network system wirelessly in a W-CDMA manner, and connected to the base station controller 130 by a LAPD / E1 line. To pass data.

The base station controller 130 is called a "Radio Port Controller (RPC)". The base station controller 130 decodes the data encoded by the digital data in the subscriber access device into the digital data of the wired network, determines the type of the call, and requests a call for asynchronous data service. Route to data service processing unit (IWF) and perform base station management

In addition, the IWF 140 performs a rate adaption function to match the data transmission speed for the wired network to perform the connection between the wireless network and the data network, and routes the data to the wired data network. After configuring the forwarding address and data format so that it can be routed, process the data call connecting to the general wired data network.

FIG. 2 is a signal flow diagram illustrating a process of converting a rate of an uplink channel according to the present invention, and illustrates a signaling procedure between a subscriber PC, a subscriber access device (RIU), a base station / base international controller (RP / RPC), and an IWF. .

In the WLL system, a forward channel includes a pilot channel, a synchronization channel, a paging channel, a forward traffic channel, and a PCS (Power Control and Signaling) channel (forward signal subchannel and forward power control and reserved information subchannel). The pilot channel consists of only zero symbols and enables the terminal station to obtain code synchronization and broadcast wave phase information of the base station signal. The sync channel delivers a 20ms sync channel frame at 8Kbps. One frame consists of 152 bits of information bits and 8 bits of encoder tail bits. The paging channel is 32 kbps and consists of 640 bit (20 ms) frames. The forward signal subchannel transmits at 4000bps and carries 72 bits of information and 8 bits of encoder tail bits in a 20ms long frame. The forward PR subchannel transmits the DTX indication information together with the power control information to the terminal station, and operates in the reverse power control mode and the power control and DTX transmission mode.

The reverse channel consists of an access channel (reverse pilot channel, access information channel) and a reverse traffic channel. The reverse traffic channel is divided into a reverse PPCS channel and a reverse traffic information channel, and the reverse PPCS channel is a reverse pilot subchannel and a reverse power. It is divided into a control subchannel, a reverse signal subchannel, and a reserved information subchannel.

The reverse pilot channel transmits only '0' symbols, through which the base station obtains the code synchronization and carrier phase synchronization information of the access channel. The access information channel transmits information of the access channel to the base station. The frame length of the access information channel is 20ms and is composed of 152 bits of information bits and 8 bits of encoder tail bits. The reverse PPCS channel is composed of 20 MUX groups in 20MS_BST, and 1MUX group is 1ms in length and is composed of 16 symbols. Eight of the 16 symbols are symbols of the reverse signaling subchannels, four symbols are symbols of the reverse pilot subchannels, and there are two symbols of the reverse power control subchannel and the reverse Rseerved Information subchannel.

Referring to FIG. 2, when the radio resource allocation is completed and the data is communicated, the data amount input from the PC is stored in the buffer and transmitted to the base station. When the amount of data detected in the buffer is reduced, the RIU 110 A change request is requested through a change request message, and a change complete message is received from the RP / RPC 120/130 to complete the channel change.

3 is a signal flow diagram illustrating a process of converting a rate of a downlink channel according to the present invention, and illustrates a signaling procedure between a subscriber PC, a subscriber access device (RIU), a base station / base international controller (RP / RPC), and an IWF. .

Referring to FIG. 3, while the allocation of radio resources is completed, data transmitted from the network side to the IWF 140 is stored in a buffer and transmitted to the RIU side through a base station while communicating data, and the actual amount of data detected in the buffer is reduced. If the change request (Modify Request) message to request the RIU 110 to change the downlink channel, and receives a change complete signal (Modify Complete) from the RIU (110) to terminate the channel change.

4 is a flowchart illustrating a process of converting a rate of an uplink channel in a terminal according to the present invention.

The radio system occupies a radio channel according to a data service request, and in this case, radio resources are allocated at a predetermined channel rate. In the data transmission / reception process, when the data transmission amount of the uplink channel is smaller than the speed of the radio channel, the data is continuously reduced by T _L , and the transmission rate is reduced according to the radio resource change procedure. If the subscriber wants to receive FTP data using the FTP port in the data transmission, most of the data transmitted from the subscriber should be transmitted at a high speed.

If the amount of data transmission buffer of the terminal is small and continuously transmitted by the timer, it is similarly smaller than the threshold, so that a radio bearer change procedure is performed. That is, if the data transmission amount of the uplink channel is continuously larger than the speed of the radio channel in the data transmission and reception process by a predetermined time (T _H ), the transmission speed is increased by changing the property of the radio resource according to the radio resource change procedure (BCM). Let's do it.

Referring to FIG. 4, in step 401, the terminal transmit port state is checked to determine whether it is FTP. If it is an FTP port, the status is maintained in step 402. If the transmission port is not FTP, the terminal transmit buffer status is checked in step 403. In step 404, the buffer status is determined and branches according to the status. For example, the size of the data stored in the buffer is called "D _BUF ", the lower limit threshold for change is called "D _TH (Low)", and the upper limit threshold for change is "D _TH (High)". D _BUF is compared with D _TH (Low) and D _TH (High), respectively.

If the comparison result shows that D _BUF is less than D _TH (Low) (D _BUF < D _TH (Low)), it is determined in step 405 whether the lower limit timer T _L is set and not set. In step 407, it is determined whether the T _L timer has expired and the current bearer speed is not Min. If the determination result expires in step 407 and is not the minimum, a bearer channel modification (BCM) procedure for reducing the uplink bearer speed is performed. If it is not expired or not minimum in step 407, the current state is maintained in step 409.

If the result of the comparison D _BUF is D _TH (High) is greater than _{(D TH (High) <D} BUF), the upper limit timer (T _H) is the determination to not set that is set (set) in step 410. Timer in step 411 In step 412, it is determined whether the T _H timer expires and the current bearer speed is not Max. If the result of the determination in step 412 expires and is not the maximum, a bearer channel modification (BCM) procedure for increasing the uplink bearer speed is performed. If it is not expired at step 412 or not at maximum, the current state is maintained at step 409.

5 is a flowchart illustrating a process of converting a rate of a downlink channel in a terminal according to the present invention. The base station requests the occupancy of the radio channel in the wireless system according to the data service request. In this case, the radio resource is allocated at a predetermined channel rate. In the process of data transmission and reception, if the amount of downlink data transmission from the IWF to the subscriber is less than the set speed of the wireless channel, and there is little data continuously by T _L , the transmission speed is reduced by changing the properties of the radio resource according to the radio resource change procedure. . Similarly, when data is transmitted from the IWF during data transmission and reception, if more data is continuously input than the speed of the downlink channel, the transmission speed is increased by increasing the property of the radio resource according to the radio resource change procedure.

Referring to FIG. 5, the network (IWF) side transmit buffer state is checked in step 501. In step 502, the buffer status is determined and branches according to the status. For example, when the size of the data stored in the buffer is called "D _BUF ", the lower limit threshold for change is called "D _TH (Low)", and the upper limit threshold for change is called "D _TH (High)", The buffered D _BUF is compared with D _TH (Low) and D _TH (High), respectively.

As a result of the comparison, if D _BUF is less than D _TH (Low) (D _BUF &lt; D _TH (Low)), it is determined in step 503 whether the lower limit timer T _L is set, and if not, in step 504 A timer is set, and in step 505 it is determined whether the T _L timer has expired and the current bearer speed is not minimum. If the result of the determination in step 505 expires and is not the minimum, a bearer channel modification (BCM) procedure for reducing the uplink bearer speed is performed in step 506. If it is not expired or minimum in step 505, the current state is maintained in step 507.

Comparative If the result D _BUF is D _TH (High) is greater than _{(D TH (High) <D} BUF), the upper limit timer (T _H) has not been set to determine whether the set (set) in step 508, in step 509 A timer is set, and in step 510 it is determined whether the T _H timer has expired and the current bearer speed is not Max. If the determination result expires in step 510 and is not the maximum, a bearer channel modification (BCM) procedure for increasing the uplink bearer speed is performed in step 511. If it is not expired at step 510 or not at maximum, the current state is maintained at step 507.

As described above, the present invention efficiently predicts the amount of data to be delivered when providing a data service in a wireless network system through buffer management and timer management, thereby adaptively changing the capacity of the allocated channel to efficiently It can be used as an effect.

Claims (3)

Checking the state of the terminal transmission buffer in the subscriber matching device; Performing channel change to reduce the bearer speed of the uplink when the data buffered in the transmission result is less than a predetermined lower limit reference value and the duration thereof passes a predetermined time; Performing a channel change to increase the bearer speed of the uplink when the data buffered in the transmission result is greater than a predetermined upper limit reference value and the duration of the test result exceeds a predetermined time; And And maintaining the current status when the data buffered in the transmission buffer is larger than a predetermined lower limit reference value and smaller than an upper limit reference value. The method of claim 1, wherein the channel conversion method does not perform channel conversion when the data transmitted from the terminal is FTP. Checking a state of a transmission buffer of a network side; Performing channel change to reduce the bearer speed of the downlink when the data buffered in the transmission result is less than a predetermined lower limit reference value, and the duration thereof passes a predetermined time; Performing a channel change to increase the bearer speed of the downlink when the data buffered in the transmission result is greater than a predetermined upper limit reference value and the duration thereof passes a predetermined time; And And maintaining the current status when the data buffered in the transmission buffer is larger than a predetermined lower limit reference value and smaller than an upper limit reference value.