KR100566976B1 - A method for selecting an adaptive data service system in mobile terminal supporting both cdma2000 system and EVDO system - Google Patents

Abstract

According to the present invention, when a dual mode wireless terminal capable of simultaneously supporting a cdma2000 1x system and an EVDO system, which is a type of a synchronous mobile communication system, receives a data service, a quality required for a specific service among the cdma2000 1x system and an EVDO system is provided. The present invention relates to a method of selecting an optimal system that satisfies the user. More specifically, the present invention relates to asymmetric service as well as asymmetric service by considering the load degree of each system and the effective bandwidth required for a specific service in the forward as well as the reverse direction. In this case, the present invention relates to a method for selecting an optimal data service system and providing a good effective bandwidth to a data service user while preventing performance degradation of each data service system.

According to the present invention, a user can be provided with a good quality of service, and can efficiently distribute the forward and reverse loads of each system to provide a more stable and efficient service system selection method.

cdma2000 1x, EVDO, free bandwidth, minimum effective bandwidth, symmetrical service, asymmetrical service

Description

A method for selecting an adaptive data service system in mobile terminal supporting both cdma2000 system and EVDO system}

1 is a flowchart illustrating a method for determining a service system when establishing a data call of a dual mode wireless terminal according to the related art.

2 is a flowchart illustrating a symmetry determination step of a data service in a method for determining a service system when establishing a data call of a dual mode wireless terminal according to the present invention.

3 is a flowchart illustrating a service system determination method when a data service is symmetric among the service system determination methods when establishing a data call of a dual mode wireless terminal according to the present invention.

4 is a flowchart illustrating a method for determining a service system when a data service is asymmetrical among service system determination methods for establishing a data call of a dual mode wireless terminal according to the present invention.

According to the present invention, when a dual mode wireless terminal capable of simultaneously supporting a cdma2000 1x system and an EVDO system, which is a type of a synchronous mobile communication system, receives a data service, a quality required for a specific service among the cdma2000 1x system and an EVDO system is provided. The present invention relates to a method of selecting an optimal system that satisfies the user. More specifically, the present invention relates to asymmetric service as well as asymmetric service by considering the load degree of each system and the effective bandwidth required for a specific service in the forward as well as the reverse direction. In this case, the present invention relates to a method for selecting an optimal data service system and providing a good effective bandwidth to a data service user while preventing performance degradation of each data service system.

There are currently two types of synchronous mobile networks based on CDMA technology. One of them is cdma2000 1x system, which was originally developed for voice call service and now supports wireless data service and supports forward and reverse service bandwidth up to 144kbps by gradually increasing forward and reverse service bandwidth according to technology development. The other is an EVDO (Evolution Data Only) system developed to support only 2.4Mbps high-speed wireless data service.

The two systems are slightly different in modulation and demodulation scheme, but because they use the same frequency band and use the same code division multiplexing scheme, a dual mode capable of simultaneously supporting the two systems in real time to receive complementary services from the two systems. Wireless terminals have been devised. At this time, since both the cdma2000 1x system and the EVDO system provide data service, when a user wants to receive data service using the dual mode wireless terminal, the wireless terminal uses either system to provide data service. You must decide if you need to receive it. Preferably, it would be desirable to select a system with the best margin at present. To this end, currently available commercially available dual-mode wireless terminal uses a simple method of selecting a service system according to the configuration of the two systems in the region where the terminal is located and the priority system selection criteria set in the terminal when the user wants data service.

Designed to improve the data service system selection method of the dual-mode terminal as described above is a method of selecting a data call service system of the dual-mode terminal (Korean Patent Application No. 2002-86091). In the present invention, a method for distributing data services to two systems is proposed to prevent data services in a corresponding area from being concentrated on a specific system. That is, the service system is selected in consideration of the load occupying the forward bandwidth of each system in consideration of the fact that the data service is mainly composed of services that occupy more of the forward bandwidth than the backward bandwidth. The patent application receives information on the forward margin of each system from each system, and selects a system having a large margin, that is, a light load, when selecting a system.

1 is a flowchart illustrating a method for determining a service system when establishing a data call of a dual mode wireless terminal according to the related art. A method of determining a conventional data service system will be described in more detail with reference to FIG. 1.                         

The prior art consists of a cdma2000 1x system and an EVDO system and a dual mode wireless terminal. First, when power is supplied to a wireless terminal, the wireless terminal monitors a pilot channel and the like to obtain each system. Then, the wireless terminal broadcasts in the control channel by the overhead message protocol received from the EVDO system and the forward margin bandwidth information of the system included in the additional channel capacity parameter message broadcast from the cdma2000 1x system on the control channel in the idle state. It continuously updates the forward margin bandwidth information of the corresponding system included in the forward bandwidth threshold message. To this end, the cdma2000 1x system broadcasts the reserved bandwidth information of the forward / reverse additional channel to all terminals in the service area whenever the service bandwidth of the forward / reverse direction is changed, and the EVDO system also provides a margin whenever the service bandwidth of the forward direction is changed. The bandwidth information is broadcast to all terminals in the service area.

If there is a data call setup request by the user, the wireless terminal selects the service system according to the procedure as shown in the flowchart shown in FIG. First, the wireless terminal first determines a system that can be serviced (S11). As a result of the determination, if only the cdma2000 1x system is possible, the cdma2000 1x system is determined as the service system, and if only the EVDO system is possible, the EVDO system is determined as the service system. If both systems are serviceable, a step of comparing the forward margin of each system is performed (S12). By comparing the forward additional channel free bandwidth of the cdma2000 1x system, which is the information provided in the idle state, with the forward free bandwidth of the EVDO system, the system having more free bandwidth is selected as the service system and the data call service is provided to the system. request.

In the above procedure, the forward additional channel bandwidth of the cdma2000 1x system and the forward margin bandwidth of the EVDO system compared by the wireless terminal are information provided by each system. The cdma2000 1x system and the EVDO system estimate a free bandwidth whenever a data service is requested by a wireless terminal in a service area and allocates a traffic channel for the data call accordingly, thereby predicting the free bandwidth and then using the wireless terminal in the service area. Broadcast to Additional channel capacity parameter messages used by the cdma2000 1x system and forward bandwidth threshold messages used by the EVDO system are disclosed in the referenced patent specification.

According to the conventional technology, when a user requests a data service, the criterion for selecting a service system considers only the forward margin bandwidth of each system but does not consider the backward margin bandwidth. However, wireless data services using a mobile communication system are various, such as Internet access, E-mail service, file transfer service, music and video on demand service, real time music and video service, and video phone service, and most of them are specific. Although the transmission speed in the direction is asymmetric service that is faster than the transmission speed in the other direction, there is also a symmetric service that supports the same bidirectional transmission speed, for example, a video telephone service. Therefore, if the requested service is symmetric, if the reverse bandwidth that the selected system can provide is much smaller than the forward bandwidth, the quality of service is good for the forward direction, but the quality of service for the reverse direction is not good for the reverse direction, which may adversely affect the overall service quality. There is a number. In particular, real-time services such as video calls can be difficult to call. In addition, since the prior art considers only the forward free bandwidth of the system without considering the minimum effective bandwidth required by a specific service, in the worst case, the service quality may be degraded even in the forward direction as well as the reverse direction. do.

As described above, in the case of the symmetric data service, the conventional technology does not consider some conditions, and thus has a problem of deteriorating the forward and reverse directions and overall service quality. Accordingly, a method of selecting a service system capable of satisfying a service quality required by a specific service in consideration of not only asymmetric but also symmetric data service is required.

The present invention is to overcome the problems of the prior art described above. Accordingly, an object of the present invention is to provide a method for selecting a service system considering both the forward and reverse spare bandwidths in order to satisfy not only asymmetric but also symmetric data services.

In addition, another object of the present invention is to select a service system in consideration of parameters such as the forward, reverse free bandwidth of each system, and the effective bandwidth required for a specific service, to distribute the forward and reverse load of each system more stable and efficient To provide services.

Method for selecting an optimal data service system in a dual mode wireless terminal simultaneously supporting the present invention cdma2000 1x and EVDO system for achieving the above object:

a) determining whether the type of data service requested by the user is asymmetrical or symmetrical;

b) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems;

c) obtaining an available bandwidth of each system according to the determination result of steps a) and b) or selecting a serviceable system as a data service system;

d) In the case of symmetrical service, the free bandwidth of each system is compared with the minimum effective bandwidth required by the service, and a system that satisfies this is selected as a data service system. Selecting a larger system as the data service system;

e) if both systems satisfy the condition in step d), comparing the free bandwidths of the two systems and selecting a system having a larger free bandwidth as a data service system.

The forward / reverse spare bandwidth information of the cdma2000 1x system and the forward / reverse spare bandwidth information of the EVDO system are provided to all terminals of the corresponding area by broadcasting through a control channel from each system. The forward / reverse spare bandwidth information of the cdma2000 1x system and the forward spare bandwidth information of the EVDO system use those presented in the related art to which the present invention refers. The reverse margin bandwidth information of the EVDO system is used without change as defined in the EVDO radio standard.                     

Now, a method of selecting a data service system in a dual mode wireless terminal simultaneously supporting the cdma2000 1x and the EVDO system will be described in detail with reference to FIGS. 2 to 4.

First, as shown in FIG. 2, upon receiving a call setup request for a data service from a user, a dual-mode wireless terminal which simultaneously supports a cdma2000 1x system and an EVDO system in real time may determine whether the type of data service requested by the user is symmetric or not. It is determined whether it is asymmetric (step S101).

3 is a flowchart illustrating a service system determination method when a data service is symmetric among the service system determination methods when establishing a data call of a dual mode wireless terminal according to the present invention. As a result of the determination in step S101, when the type of data service requested by the user is symmetric, as illustrated in FIG. 3, first, a serviceable candidate system is determined (S201). If only the cdma2000 1x system can be serviced as a result of the determination in step S201, the smaller one of the forward and reverse spare bandwidths is selected as the free bandwidth of the corresponding cdma2000 1x system (S202). The smaller one of the backward spare bandwidth is selected as the spare bandwidth of the EVDO system (S203) to derive the spare bandwidth of each system. If, as a result of the determination of step S201, both systems are serviceable, both the step of deriving the free bandwidth of the cdma2000 1x system (S202) and the step of deriving the free bandwidth of the EVDO system (S203) are performed.

Thereafter, comparing the derived free bandwidth of each system with the minimum effective bandwidth required by the service is performed (S204). If only the cdma2000 1x system can be serviced, if the free bandwidth of the cdma2000 1x system is compared with the minimum effective bandwidth required by the service, the cdma2000 1x system is selected. If not, the cdma2000 1x system is required. Inform the user that the service cannot be performed due to the absence of a system that can accommodate the minimum effective bandwidth. In addition, if only the EVDO system is serviceable, the EVDO system is selected if the EVDO system is satisfied by comparing the available bandwidth of the EVDO system with the minimum effective bandwidth required by the service. If the EVDO system is not satisfied, the minimum required for the symmetric data service requested by the user is satisfied. Inform the user that the service cannot be performed due to the absence of a system that can accommodate the effective bandwidth. If both systems are serviceable, if only the cdma2000 1x system can accommodate the service request bandwidth as a result of the determination in step S204, the cdma2000 1x system is selected as the corresponding service system, and only the EVDO system accepts the service request bandwidth. If possible, select the EVDO system as the service system.

As a result of the determination in step S204, when both systems can accommodate the minimum effective bandwidth, a system with less load is selected as a service system by comparing the free bandwidths of the two systems with each other (S205). As a result of performing step S205, if the cdma2000 1x system has a larger margin, a cdma2000 1x system with a smaller load is selected. If the cdma2000 1x system has a larger margin, an EVDO system with a smaller load is selected. . However, if neither system can satisfy the minimum effective bandwidth, then the user is informed that the service cannot be performed due to the absence of a system that can accommodate the minimum effective bandwidth required for the symmetric data service required by the user.

4 is a flowchart illustrating a service system determination method when a data service is asymmetric among the service system determination methods when establishing a data call of a dual mode wireless terminal according to the present invention. As a result of the determination in step S101, when the type of data service requested by the user is symmetric, as illustrated in FIG. 4, first, a serviceable candidate system is determined (S301). As a result of the determination in step S301, if only one of the cdma2000 1x system and the EVDO system is serviceable, the serviceable system is selected as the service system of the service requested by the user and the procedure is terminated. For example, if only the cdma2000 1x system is serviceable, the cdma2000 1x system is selected as the service system of the service requested by the user. If only the EVDO system is serviceable, the EVDO system is selected as the service system.

On the other hand, if the cdma2000 1x system and the EVDO system are both serviceable as a result of the determination in step S301, the forward and reverse spare bandwidths of the cdma2000 1x system are obtained and derived respectively (S302), and the forward and reverse spare bandwidths of the EVDO system are determined. Each step of obtaining and deriving is performed (S303). Thereafter, the forward free bandwidth and the reverse free bandwidth of the cdma2000 1x system and the EVDO system derived through the steps S302 and S303 are compared with each other to determine which of the free bandwidths is larger (S304). As a result of the comparison, a system whose forward free bandwidth is larger than the free reverse bandwidth is selected as the service system for the asymmetric data service. That is, if the cdma2000 1x system has a larger forward bandwidth and the EVDO system has a larger backward bandwidth, the cdma2000 1x system is selected as the service system. In contrast, if the cdma2000 1x system has a larger free bandwidth in the reverse direction and the EVDO system has a larger free bandwidth in the forward direction, the EVDO system is selected as the service system.

If both systems have more free bandwidth in the forward direction than the free bandwidth in the reverse direction, or both systems have more free bandwidth in the reverse direction than the forward free bandwidth, the forward or reverse free bandwidth of the two systems can be compared again to finally determine the service system. To select (S305). As a result of the step (S305), if the forward or reverse spare bandwidth of cdma2000 1x is larger than the forward or reverse spare bandwidth of the EVDO system, the cdma2000 1x system is selected as the service system, and in the opposite case, the EVDO system is selected as the service system. .

As can be seen from the comparison between FIG. 3 and FIG. 4, unlike the case where the data service is symmetric, in the case of the asymmetry, the step of comparing the free bandwidth of each system with the minimum effective bandwidth required by the service is not performed. The symmetric service is a data service having the same forward and reverse data rates, and is mainly used when data transmission needs to be performed in real time, such as a video telephone service. Therefore, the free bandwidth of each system must be larger than the minimum required bandwidth. . However, the asymmetric service does not require the minimum effective bandwidth because the transmission speed in one direction may be larger than the transmission speed in the other direction depending on the situation.

Through the above-described method, the dual mode wireless terminal selects one of the cdma2000 1x system and the EVDO system as a system for providing data service. The selection function may be performed through a computer executable program installed in the terminal, similar to the additional function of the terminal.

So far, the method of selecting a service system for a data service when a call setup request for a data service is received from a user in a dual mode wireless terminal simultaneously supporting a cdma2000 1x and an EVDO system has been described. As described above, the data call service system selection method of the dual mode wireless terminal according to the present invention can obtain the following advantages over the prior art.

First, the service system was selected in consideration of only asymmetric data service, but the present invention selects an optimal service system for each data service characteristic in consideration of the symmetric data service, so that the user can be provided with high quality service. There is an advantage.

Second, since the service system is selected in consideration of parameters such as forward, reverse free bandwidth of each system, and effective bandwidth required by a specific service, the forward and reverse loads of each system are efficiently distributed to select a more stable and efficient service system. It may provide a method.

Claims (12)

A method for selecting a data service system in a dual mode wireless terminal supporting simultaneous cdma2000 1x and EVDO systems, the method comprising: a) determining whether the type of data service requested by the user is asymmetrical or symmetrical; b) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems; c) obtaining an available bandwidth of each system according to the determination result of steps a) and b) or selecting a serviceable system as a data service system; d) In the case of symmetrical service, the free bandwidth of each system is compared with the minimum effective bandwidth required by the service, and a system that satisfies this is selected as the data service system.In the case of an asymmetrical service, the free bandwidth in the forward direction is the free bandwidth in the reverse direction. Selecting a larger system as the data service system; e) if both systems satisfy the condition in step d), comparing the free bandwidths of the two systems and selecting a system having a larger free bandwidth as a data service system. . The method of claim 1, If only one of the cdma2000 1x or EVDO system is serviceable as a result of the determination of step b), only the free bandwidth of the serviceable system is obtained in the case of the symmetric service, and in the case of the asymmetric service, the serviceable in the step c). A method of selecting an adaptive data service system, characterized in that the system is selected as a data service system. The method of claim 1, If the determination result of step b) is available for both systems, the adaptive data service system selection method characterized in that to obtain the free bandwidth of both systems. The method according to any one of claims 1 to 3, If the data service requested by the user is symmetrical, the smaller one of the forward and backward bandwidths is used as the free bandwidth of each system, and in the asymmetric type, both the forward and backward bandwidths of each system are used. Adaptive data service system selection method characterized in that the. The method according to any one of claims 1 to 3, The forward / reverse spare bandwidth information of the cdma2000 1x system and the forward / reverse spare bandwidth information of the EVDO system are provided to all terminals of the corresponding area from the respective systems by broadcasting through a control channel. . The method of claim 1, If the data service requested by the user in step d) is symmetric, informing the user that no service is performed in the absence of a system that can accommodate the minimum effective bandwidth if no system satisfies the minimum effective bandwidth. Adaptive data service system selection method further comprising the step. A method for selecting a data service system in a dual mode wireless terminal supporting simultaneous cdma2000 1x and EVDO systems, the method comprising: 1) determining whether the type of data service requested by the user is asymmetrical or symmetrical; 2) If the type of data service requested by the user is symmetric: a) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems; b) obtaining the free bandwidth of the cdma2000 1x or EVDO system or the free bandwidth of both systems according to the determination result of step a); c) comparing the free bandwidth of the cdma2000 1x or EVDO system with the minimum effective bandwidth required by a service; d) selecting a system satisfying the minimum effective bandwidth as the data service system according to the comparison result of step c), and selecting a system having a larger free bandwidth as the data service system when both systems satisfy the minimum effective bandwidth. step; 3) If the type of data service requested by the user is asymmetric: e) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems; f) according to the determination result of step e), if only one system is serviceable, select the system as a data service system, and if both systems are serviceable, calculating forward and reverse spare bandwidths of both systems; ; g) selecting one of the two systems whose forward bandwidth is larger than the backward bandwidth and selecting the data service system; h) when the forward bandwidth is greater or smaller than the forward bandwidth in both systems, selecting a system having a large free bandwidth as a data service system by comparing the forward or reverse spare bandwidth of the two systems with each other; Adaptive data service system selection method comprising a. The method of claim 7, wherein In step c), the free bandwidth of the system is determined as the free bandwidth of the forward free bandwidth and the reverse free bandwidth as the free bandwidth of the system, characterized in that the adaptive bandwidth. The method according to claim 7 or 8, The forward / reverse spare bandwidth information of the cdma2000 1x system and the forward / reverse spare bandwidth information of the EVDO system are provided to all terminals of the corresponding area from the respective systems by broadcasting through a control channel. . The method of claim 7, wherein And in the step d), if any system does not satisfy the minimum effective bandwidth, informing the user that the service cannot be performed in the absence of a system that can accommodate the minimum effective bandwidth. How to select a service system. 1) determining whether the type of data service requested by the user is asymmetrical or symmetrical; 2) If the type of data service requested by the user is symmetric: a) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems; b) obtaining the free bandwidth of the cdma2000 1x or EVDO system or the free bandwidth of both systems according to the determination result of step a); c) comparing the free bandwidth of the cdma2000 1x or EVDO system with the minimum effective bandwidth required by a service; d) selecting a system satisfying the minimum effective bandwidth as the data service system according to the comparison result of step c), and selecting a system having a larger free bandwidth as the data service system when both systems satisfy the minimum effective bandwidth. step; 3) If the type of data service requested by the user is asymmetric: e) determining a serviceable system at a current location of a wireless terminal among the cdma2000 1x or EVDO systems; f) according to the determination result of step e), if only one system is serviceable, select the system as a data service system, and if both systems are serviceable, calculating forward and reverse spare bandwidths of both systems; ; g) selecting one of the two systems whose forward bandwidth is larger than the backward bandwidth and selecting the data service system; h) when the forward bandwidth is greater or smaller than the forward bandwidth in both systems, selecting a system having a large free bandwidth as a data service system by comparing the forward or reverse spare bandwidth of the two systems with each other; A dual-mode wireless terminal that simultaneously supports the cdma2000 1x and EVDO systems to select an adaptive data service system among the cdma2000 1x system and the EVDO system. The method of claim 11, The adaptive data service system selection function is a dual mode wireless terminal, characterized in that made through a computer running program installed in the terminal.

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