KR100358165B1 - Method for dicision of changing to USTS in wireless telecommunication system - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a method for determining uplink synchronous transmission conversion in a wireless communication system and a computer-readable recording medium having recorded thereon a program for realizing the method.

2. The technical problem to be solved by the invention

The present invention, in the asynchronous mobile communication system, when the mobile station initially registers in the network or registers after completing the handoff, the mobile station to suppress the unnecessary conversion of the USTS mode to reduce the probability of occurrence of service failure and call quality degradation To provide a USTS conversion determination method and a computer-readable recording medium recording a program for realizing the method.

3. Summary of Solution to Invention

The present invention relates to a method for determining a conversion to an uplink synchronous transmission mode (USTS, hereinafter referred to as "USTS") mode in a wireless communication system, when a mobile station newly registers in a wireless network. Checking whether the wireless network to be performed is a network supporting the USTS; And according to the inspection result, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm, and the required quality of service (QoS) is suitable for the USTS and the moving speed. And if it satisfies the USTS, determining to change to the USTS mode.

4. Important uses of the invention

The present invention is used in the IMT-2000 system.

Description

Method for determining uplink synchronous transmission scheme conversion in wireless communication system {Method for dicision of changing to USTS in wireless telecommunication system}

The present invention relates to a method of determining a conversion to an uplink synchronous transmission scheme (USTS) mode in a wireless communication system and a program for realizing the method. The present invention relates to a recording medium, and more particularly, to a method of determining a conversion to USTS mode when a mobile station (UE) registers in a network or registers in a network after a handoff is completed in an asynchronous mobile communication system. It is about.

In a conventional code division multiple access (CDMA) mobile communication network, a call generated between a mobile station and a base station includes a forward channel and a reverse channel. A plurality of forward channels between a plurality of mobile stations and a base station existing in a base station are synchronized with each other using timing information, and each channel is decoded using an orthogonal code having orthogonality between channels. The interference can be significantly reduced. However, since the reverse channel from the mobile station to the base station does not use the timing information and cannot be synchronized, orthogonality cannot be used, and thus the reverse interference increases as the channel of the mobile station increases. As a result, the capacity in the reverse direction is eventually limited.

Therefore, in order to increase the capacity in the reverse direction, all mobile stations may synchronize in the reverse direction using the same time information between channels, thereby minimizing interference between channels by orthogonal codes using orthogonality. . This method is called "Uplink Synchronous Transmission Scheme".

Although this USTS has many advantages, the applicable environment is limited and the mobile station must selectively change to the USTS mode.

USTS is a technology that allows the base station to control the transmission time of the reverse data for the mobile stations in the cell managed by the base station so that the reverse signal of the mobile station using the orthogonal code can arrive simultaneously at the reference time desired by the base station. In this way, the characteristics of the orthogonal code can be maximized, thereby maximizing the transmission capacity in the cell.

However, in order for the mobile station to use the USTS, it must decide whether or not to use the USTS when the mobile station initially registers in the network or performs handoff registration with the new network. Otherwise, there is a problem that the mobile station may unnecessarily switch to the USTS mode, which may cause a service interruption and call quality deterioration.

In order to solve the problems described above, the present invention, when the mobile station initially registers in the network or registers in the network after the handoff is completed in the asynchronous mobile communication system, it prevents the mobile station from switching to unnecessary USTS mode. It is an object of the present invention to provide a USTS conversion determination method for reducing the probability of occurrence of a failure and call quality degradation, and a computer-readable recording medium recording a program for realizing the method.

1 is an exemplary configuration diagram of a wireless communication system to which the present invention is applied.

2 is a flowchart illustrating a method for determining uplink synchronous transmission (USTS) conversion in a mobile station according to the present invention.

3 is an explanatory diagram showing a time point when a mobile station should perform a method for determining uplink synchronous transmission (USTS) conversion upon initial registration with a network according to an embodiment of the present invention;

FIG. 4 is an explanatory diagram showing a time point when a mobile station performs a method for determining uplink synchronous transmission (USTS) conversion when registering a mobile station after performing a handoff according to an embodiment of the present invention; FIG.

* Explanation of symbols for the main parts of the drawings

10: mobile station (UE) 20: base station (Node B)

30: control station (RNC) 40: core network (Core Network)

In order to achieve the above object, the present invention provides a method for determining a conversion to an uplink synchronous transmission mode (USTS) mode in a wireless communication system. Checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS; And according to the inspection result, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm, and the required quality of service (QoS) is suitable for the USTS and the moving speed. If it satisfies the USTS, characterized in that it comprises the step of changing to the USTS mode.

The present invention is further characterized in that the mobile station continues to operate in a non-USTS mode if the asynchronous radio network does not support the USTS according to the test result.

The present invention is further characterized in that the mobile station continues to operate in the non-USTS mode when the mobile station requires a spreading factor SF higher than the spreading factor (SF) 256.

The present invention is also characterized in that the mobile station continues to operate in a non-USTS mode if the quality of service (QoS) required by the mobile station is not suitable for the USTS.

The present invention is further characterized in that the mobile station continues to operate in a non-USTS mode if the mobility of the mobile station is high speed (preferably walking speed, 4Km or more).

In order to achieve the above object, the present invention provides a method for determining a conversion to an uplink synchronous transmission mode (USTS, " USTS ") mode in a wireless communication system. Checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS when newly registering with the mobile station; And according to the inspection result, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm, and the required quality of service (QoS) is suitable for the USTS and the moving speed. If it satisfies the USTS, characterized in that it comprises the step of changing to the USTS mode.

The present invention is further characterized in that the mobile station continues to operate in a non-USTS mode if the asynchronous radio network does not support the USTS according to the test result.

The present invention is further characterized in that the mobile station continues to operate in the non-USTS mode when the mobile station requires a spreading factor SF higher than the spreading factor (SF) 256.

The present invention is also characterized in that the mobile station continues to operate in a non-USTS mode if the quality of service (QoS) required by the mobile station is not suitable for the USTS.

In addition, the present invention is characterized in that it further comprises a third step of the mobile station continues to operate in a non-USTS mode, if the mobility (Mobility) of the mobile station is a high speed (preferably walking speed, 4Km or more) do.

In order to achieve the above object, the present invention provides a mobile communication system in a wireless communication system having a processor to determine a conversion to an uplink synchronous transmission mode (USTS, hereinafter referred to as "USTS") mode. A first function of checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS when registering; And if the wireless network supports the USTS according to a test result of the first function, a spreading factor (SF) necessary for the mobile station is suitable for a channel allocation algorithm and a required quality of service (QoS) is transmitted to the USTS. Provided is a computer readable recording medium having recorded thereon a program for realizing a second function of determining to change to the USTS mode when the moving speed satisfies the USTS.

In addition, the present invention provides a wireless communication system having a processor to determine a conversion to an uplink synchronous transmission mode (USTS, hereinafter referred to as "USTS") mode. A first function of checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS when newly registering; And if the wireless network supports the USTS according to a test result of the first function, a spreading factor (SF) necessary for the mobile station is suitable for a channel allocation algorithm and a required quality of service (QoS) is transmitted to the USTS. Provided is a computer readable recording medium having recorded thereon a program for realizing a second function of determining to change to the USTS mode when the moving speed satisfies the USTS.

The present invention is based on a next generation mobile communication network such as International Mobile Telecommunication (IMT-2000) and Universal Mobile Telecommunication Service (UMTS), and more preferably, after a mobile station registers with a network and completes a handover in an IMT-2000 between base stations. When you register with, you decide to switch to USTS mode.

To this end, in the present invention, whether the mobile station may use the USTS in consideration of various factors, preferably spreading factor (SF), quality of service (QoS), and mobility (Mobility). Determine.

Therefore, according to the present invention, it is possible to suppress the mobile station from being unnecessarily switched to the USTS mode, thereby reducing the probability of occurrence of service failure and call quality degradation.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an exemplary configuration diagram of a wireless communication system to which the present invention is applied, and illustrates an asynchronous mobile communication system (UTRAN) environment as an example. In the figure, "10" represents a mobile station (terminal (UE), "20" represents a base station (Node B), "30" represents a control station (RNC: Radio Network Controller), and "40" represents a core network). Represent each.

As shown in FIG. 1, an asynchronous mobile communication system (UTRAN) includes a mobile station (terminal (UE)) 10, an asynchronous radio network (base station (Node B) 20 and a control station (RNC) 30), And it is configured to be organically connected between the wireless communication core network (for example, GSM-MAP Core Network, etc.) (40). Here, the method for determining the conversion to the USTS mode is a technique applied to the mobile station 10, and is a technique used when the mobile station initially registers in the network or registers in the network after completing the handoff.

The mobile station 10 is in the range of any base station 20, the information of the mobile station 10 is transmitted to the core network 40 via the base station 20 and the control station 30 controlling it, and the core network ( Information transmitted from 40 is transmitted to mobile station 10 via control station 30 and base station 20.

The mobile station 10 is a wireless terminal including a mobile terminal, a personal digital assistant (PDA), and the like, which the user can carry and communicate with while moving. The mobile station 10 uses a forward channel when receiving data, and a reverse direction when calling. Use a reverse channel.

The voice, text and video messages transmitted and received by the mobile station 10 are connected to the control station 30 through the base station 20 for high frequency signal processing and call processing.

The base station 20 connects the mobile station 10 to the control station 30, performs wireless communication with the mobile station 10, and performs a wired / wireless conversion function of performing communication with the control station 30 by wire.

The control station 30 adjusts the connection between the base stations 20 by connecting a plurality of base stations 20 and performs a signal processing function for communication between the base station 20 and the core network 40.

When the USTS transmits signals of the plurality of mobile stations 10 in one base station 20 in the reverse direction in accordance with a reference time managed by the base station 20, the USTS maintains orthogonality between the respective channels to maintain the orthogonality between the respective mobile stations 10. This is to increase network efficiency by minimizing mutual interference.

USTS is a scheme for effectively using orthogonal codes for the reverse channel as in the forward channel. That is, all mobile stations 10 use the same scrambling code in the same cell, and the distinction of each mobile station 10 uses orthogonalized channel codes. At this time, the channel code used has a limitation in use because it must consider orthogonality.

These limitations are as follows.

Since the channel allocation algorithm considered until now considers that the spreading factor (SF) is 256, the mobile station 10 cannot use the USTS when a service requiring SF 256 or more is required. Further, even if the QoS required by the mobile station 10 exceeds the range that the USTS can support, the mobile station 10 cannot change the USTS. Finally, USTS ultra-low speed service. That is, even when the mobile station 10 is carrying out a movement exceeding a certain speed (preferably, walking speed is about 4 km / h), the USTS cannot support the mobile station 10. Therefore, the mobile station 10 should limit the mode change to the USTS.

As such, if the mobile station 10 registers with the asynchronous wireless network and the USTS supports the USTS, the mode change should be determined in consideration of factors (SF, QoS, moving speed, etc.) that may affect the change to the USTS.

2 is a flowchart illustrating a method for determining uplink synchronous transmission (USTS) conversion in a mobile station according to the present invention.

As shown in FIG. 2, the method for determining conversion to USTS mode in the mobile station 10 according to the present invention may be performed when the mobile station 10 newly registers in an asynchronous radio network or newly registers after performing a handoff ( In operation 201, the mobile station 10 determines whether the asynchronous wireless network to be newly registered is a network supporting the USTS. This is possible because the control station 30 informs the mobile station 10 requesting a new registration whether it can support the USTS when performing the measurement control procedure. Accordingly, the mobile station 10 determines whether the asynchronous radio network can support USTS through the USTS indicator of this message.

If it is determined that the asynchronous wireless network does not support USTS, the mobile station 10 continues to operate in the non-USTS mode (207).

As a result, if the asynchronous wireless network supports the USTS, the mobile station 10 checks the Spreading Factor (SF) necessary for the mobile station 10 (203). This is to check whether the SF is suitable for the channel allocation algorithm of the mobile station 10. If it is necessary to assign a channel code using SF 256 in a normal case, the mobile station 10 proceeds to the next procedure for determining a USTS mode conversion decision, while the mobile station 10 receives an SF. If a higher SF than 256 is required (in this case, the mobile station 10 requires a wider band of services, and in the case of a data service, an SF larger than 256 may be required for a large data service). The mobile station 10 cannot continue using the USTS and must continue to operate in the non-USTS mode (207).

On the other hand, if the asynchronous radio network supports USTS and the SF required by the mobile station 10 is 256, the mobile station 10 analyzes the required QoS (204) to determine the change to the USTS mode.

As a result of the analysis, if the QoS required by the mobile station 10 is not suitable for the USTS, the mobile station 10 continues to operate in the non-USTS mode (207).

As a result of the analysis, if the QoS required by the mobile station 10 is suitable for the USTS, the mobile station 10 measures its own mobility to determine whether it is a low mobility situation (205). Because the USTS is basically able to support the fixed state or the mobility of the pedestrian level, if the mobile station 10 is moving faster than the pedestrian level, the change to the USTS mode is impossible. . Thus, in this case the mobile station 10 must continue to operate in the non-USTS mode (207).

In summary, when the mobile station 10 newly registers in the asynchronous wireless network or newly registers after performing handoff, the mobile station 10 indicates that the SF that the asynchronous wireless network to register newly supports USTS and the mobile station 10 requests. 256, and if the QoS required by the mobile station 10 is suitable for the USTS and its mobility is fixed or low mobility (preferably a pedestrian speed), it decides to change to the USTS mode.

Looking at the time when the change determination method to the USTS mode as described above should be performed as follows.

As shown in Fig. 3, basically, the mobile station 10 informs the asynchronous wireless network of its capability when newly registering with the asynchronous wireless network. Therefore, it is necessary to determine whether to change to the USTS mode before the procedure of informing the capability of the mobile station 10. According to this decision, the capability of the mobile station 10 is different, which in turn depends on the function of the physical components in the asynchronous wireless network.

On the other hand, as shown in Fig. 4, even when the mobile station 10 performs a handoff and newly registers the asynchronous wireless network (that is, the mobile station moves a cell and registers in a new cell), the method for determining change to USTS mode is performed. The timing to be made is the same.

The method of the present invention as described above may be implemented as a program and stored in a computer-readable recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.).

The present invention described above is capable of various substitutions, modifications, and changes without departing from the spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited to the drawing.

As described above, the present invention can prevent the mobile station from being unnecessarily switched to the USTS mode, thereby reducing the probability of occurrence of a service failure and call quality deterioration. , Bandwidth, etc.) can be increased (approximately 10-20%).

Claims (18)

In the method of determining the conversion to the uplink synchronous transmission method (USTS, "USTS") mode in the wireless communication system, When the mobile station newly registers with a wireless network, checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS; And According to the inspection result of the first step, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm and the required quality of service (QoS) is suitable for the USTS. And if the moving speed satisfies the USTS, determining to change to the USTS mode. Method for determining uplink synchronous transmission scheme conversion in a wireless communication system comprising a. The method of claim 1, The wireless network, Substantially, an uplink synchronous transmission method conversion determination method in a wireless communication system, characterized in that the asynchronous wireless network The method of claim 1, The diffusion factor (SF), Substantially, the method for determining uplink synchronous transmission scheme conversion in a wireless communication system, characterized in that 256. The method of claim 2, A third step in which the mobile station continues to operate in a non-USTS mode if the asynchronous wireless network does not support the USTS according to the check result of the first step Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 3, wherein A third step in which the mobile station continues to operate in a non-USTS mode if the mobile station requires a spreading factor (SF) higher than spreading factor (SF) 256 Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 1, A third step in which the mobile station continues to operate in a non-USTS mode if the quality of service (QoS) required by the mobile station is not suitable for the USTS; Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 1, A third step in which the mobile station continues to operate in a non-USTS mode if the mobility of the mobile station is high speed (preferably walking speed, more than 4 km / h). Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method according to any one of claims 1 to 7, The mobile station, When registering to a new asynchronous wireless network, the information on its own capability to inform the asynchronous wireless network, characterized in that before the procedure of informing its own capability to determine whether to change to the USTS mode wireless A method of determining uplink synchronous transmission scheme conversion in a communication system. In the method of determining the conversion to the uplink synchronous transmission method (USTS, "USTS") mode in the wireless communication system, When the mobile station newly registers with the wireless network after performing a handoff, checking whether the wireless network to be newly registered by the mobile station is a network supporting the USTS; And According to the inspection result of the first step, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm and the required quality of service (QoS) is suitable for the USTS. And if the moving speed satisfies the USTS, determining to change to the USTS mode. Method for determining uplink synchronous transmission scheme conversion in a wireless communication system comprising a. The method of claim 9, The wireless network, Substantially, an uplink synchronous transmission method conversion determination method in a wireless communication system, characterized in that the asynchronous wireless network The method of claim 9, The diffusion factor (SF), Substantially, the method for determining uplink synchronous transmission scheme conversion in a wireless communication system, characterized in that 256. The method of claim 10, A third step in which the mobile station continues to operate in a non-USTS mode if the asynchronous wireless network does not support the USTS according to the check result of the first step Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 11, A third step in which the mobile station continues to operate in a non-USTS mode if the mobile station requires a spreading factor (SF) higher than spreading factor (SF) 256 Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 9, A third step in which the mobile station continues to operate in a non-USTS mode if the quality of service (QoS) required by the mobile station is not suitable for the USTS; Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method of claim 9, A third step in which the mobile station continues to operate in a non-USTS mode if the mobility of the mobile station is high speed (preferably walking speed, more than 4 km / h). Uplink synchronous transmission method conversion determination method in a wireless communication system further comprising. The method according to any one of claims 9 to 15, The mobile station, When registering to a new asynchronous wireless network, the information on its own capability to inform the asynchronous wireless network, characterized in that before the procedure of informing its own capability to determine whether to change to the USTS mode wireless A method of determining uplink synchronous transmission scheme conversion in a communication system. In a wireless communication system having a processor for determining a conversion to an uplink synchronous transmission method (USTS, hereinafter referred to as "USTS") mode, A first function of checking whether the wireless network to be newly registered at the mobile station is a network supporting the USTS when the mobile station newly registers with the wireless network; And According to the test result of the first function, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm and the required quality of service (QoS) is suitable for the USTS. And a second function of changing to the USTS mode when the moving speed satisfies the USTS. A computer-readable recording medium having recorded thereon a program for realizing this. In a wireless communication system having a processor to determine a conversion to an uplink synchronous transmission method (USTS, hereinafter referred to as "USTS") mode, A first function of checking whether the wireless network to be newly registered at the mobile station supports the USTS when the mobile station newly registers with the wireless network after performing the handoff; And According to the test result of the first function, if the wireless network supports the USTS, the spreading factor (SF) necessary for the mobile station is suitable for the channel allocation algorithm and the required quality of service (QoS) is suitable for the USTS. And a second function of changing to the USTS mode when the moving speed satisfies the USTS. A computer-readable recording medium having recorded thereon a program for realizing this.