Patent Application
20060035636
The invention relates to the provision of services for users of a mobile communication network, who are also able to use another access network, such as a WLAN (Wireless Local Area Network) access network that is complementary to the mobile communication network.
The current development towards truly mobile computing and networking has brought on the evolvement of various access technologies that provide the users with access to the Internet, real-time and other telecommunications services also when they are outside their home network. At present, wireless Internet access is typically based on either wireless LAN technology or mobile networks, or both.
In wireless LAN technology, user terminals are provided with wireless LAN connections, whereby they can access, for instance, the Internet through wireless LAN access points, which are mainly located in various hot spots, such as airports, convention centers, railway stations, or shopping malls.
An example of the new mobile network technologies enabling Internet access is GPRS (General Packet Radio Service). GPRS aims at providing high-quality services for present GSM subscribers by efficiently utilizing the current network infrastructure and protocols. GPRS has evolved from GSM with the introduction of two new network elements: SGSN (Serving GPRS Support Node) and GGSN (Gateway GPRS Support Node). These elements will also provide packet-based services in the upcoming UMTS (Universal Mobile Telecommunication System) networks.
What is known as multimode radio technology is also becoming more and more common in user devices. Having his or her mobile terminal equipped with a multimode radio technology, the user can choose the most suitable network type in each case, i.e. the user can choose whether the services are accessed through GPRS or WLAN, for example. For instance, the user may sometimes prefer the higher data rate offered by the WLAN networks.
A drawback relating to the selection of the network through which the services are accessed is that the user cannot always be aware of where WLAN services are available. It is not feasible to perform the search for the WLAN access network continuously, due to a too high current consumption of the user terminal during the search. On the other hand, performing the search every 15 minutes, for example, may not be enough in the user's point of view.
An object of the present invention is thus to provide a method and an arrangement for implementing the method so as to overcome the above problem. The objects of the invention are achieved by a method, a system, a network, a user terminal and a software product, which are characterized by what is stated in the independent claims. The embodiments of the invention are disclosed in the dependent claims.
The invention is based on the idea of providing access point information on access points, selected from access networks complementary to a cellular communications network, and on cells whose signals can be received by the user terminal in the area of a certain complementary access point. According to the invention, as the user terminal receives signals in its current location in the cellular communications network it at the same time compares received signals with the maintained access point information. If the received signals correspond to the maintained access point information, it can be concluded that a complementary access point is available at that area and the user terminal is able to search for the signal of the complementary access point.
The invention provides a mechanism that alleviates the problem related to the local nature of the WLAN services. Thus the user may easily get information about the WLAN coverage in the neighborhood. The mobile terminal is able to find out about the complementary access network even when the mobile terminal is in the idle state thus reducing power consumption in the terminal. Existing mobile cell signalling can be utilized.
In the following the invention will be described in greater detail by means of preferred embodiments with reference to the accompanying drawings, in which
The embodiments of the present solution will be described below implemented in a 3G WCDMA (Wideband code division multiple access) mobile communication system, such as the UMTS (Universal mobile telecommunications system). However, the invention is not restricted to these embodiments, but it can be applied in any communication system capable of providing a sufficient coverage. Examples of such mobile systems are IMT-2000, IS-41, CDMA2000, GSM (Global system for mobile communications) or other similar mobile communication systems, such as the PCS (Personal communication system) or the DCS 1800 (Digital cellular system for 1800 MHz). Specifications of communications systems in general and of the IMT-2000 and the UMTS in particular are being developed rapidly. Such a development may require additional changes to be made to the present solution. Therefore, all the words and expressions should be interpreted as broadly as possible and they are only intended to illustrate and not to restrict the invention. What is essential for the present solution is the function itself and not the network element or the device in which the function is implemented.
The present solution utilizes a mechanism that allows a mobile user to find the nearest or otherwise most suitable WLAN access point(s). It is to be noted that in this context the “access point” is a general term, which may refer to an individual WLAN base station (i.e. physical access point) or to a WLAN network or sub-network including several contiguous (physical) access points. Although the invention is especially useful for WLAN access networks, it can be applied in connection with any other radio access network that is complementary to the mobile communication system, such as in a network implementing Bluetooth, infrared, UWB (Ultra wideband) or Flarion technology. Generally, the present solution thus allows the user to find the most suitable network access point. An access point is a site where a connectivity service is available. The users may use any terminals appropriate for communicating with the mobile communication network, such as intelligent phones, portable computers, or PDA (Personal digital assistant) equipment. Although the terminal used to find the access points is typically a multimode terminal capable of accessing the services through the mobile network and the external access network, it may also be different than the terminal for which an access point is needed. For example, a mobile phone may be used to find the most suitable access point for a traditional WLAN terminal. The complementary access network may herein refer to an external access network outside the mobile communications system, wherein the external access network and the mobile communications system are operated and maintained by different operators. It may also refer to an access network that is somehow integrated to the mobile communications system and that is operated and maintained by the same operator as the mobile communications system.
Referring to
In step 2-3, the user terminal MS stores access point information relating to at least one access point AP and the respective cells C1, C2, C3 from which the user terminal MS would be able to receive signalling if the user terminal MS were on the coverage area of said at least one access point AP or near the coverage area thereof. The access point information may concern the identity of the overlapping and nearby mobile cells, and/or information on which kind of measurements, e.g. signal strength values, can be expected to be measured in the user terminal MS when receiving signals from the mobile cells C1, C2, C3 in the coverage area of a certain WLAN or near the coverage area thereof. The information may also be acquired by the user terminal MS such that the MS is able to store access point information relating to the mobile cells C1, C2, C3 while it is registered to a certain WLAN, and to utilize the information later when visiting the same area again. The storing of the information may herein refer to short-term or long-term storing, depending on which one is more suitable.
In step 2-4, the user terminal MS is located in the mobile cell C1, and the user terminal MS receives and measures the signals received from the current cell C1 and from cells that are neighbour cells C2, C3 to the current cell. The user terminal MS may measure the signals periodically such that the measuring is repeated at predetermined intervals, for example every 30 seconds. The existing signalling and measurements of the prior art mobile communication networks can be utilized.
In step 2-5, the received signals are compared in MS with the access point information stored in step 2-3. For example, the identity of the transmitting cells and/or their signal level at the current location of the MS is examined. If access point information, corresponding in predefined boundaries to the received signals, can be found stored in the user terminal MS, it is concluded in the MS in step 2-6 that at the current location thereof or close thereto there is at least one complementary access network such as a WLAN access network available for the MS, as indicated by the access point information. In this case the process continues to step 2-7. If access point information corresponding to the received signals is not found stored in the user terminal MS, it is concluded in the MS that no external access networks are available for it at the current location thereof. In that case the process returns to step 2-4, where the user terminal MS continues to measure received signals as described above.
In step 2-7, as it has been concluded in the user terminal MS that there is at least one external access network, such as a WLAN access network, available for it, the user terminal MS starts to search for the signal of the respective external access network WLAN based on the stored access point information, and it may begin the registration process to WLAN.
An advantage of the present solution is that it does not require a location system, such as GPS (Global positioning system), to be implemented in the user terminal in order to find out about external access points. Even if there is a location system implemented in the user terminal, the location system does have to be used in order to find an external access point, thus reducing power consumption in the terminal.
According to another embodiment of the present solution, the user terminal is arranged to give an indication to the user when it has found and/or registered to a complementary access network WLAN. The indication may comprise, for example, a beep and/or a message displayed. If the user terminal is near the WLAN network, the indication may comprise an indication of where the user terminal should be moved in order to register.
According to yet another embodiment of the present solution, if more than one access point is found for the user terminal at a certain location, the most suitable access point is selected. The selection of the access is based on a predetermined criteria. Thus a prioritisation list of access points is stored in the MS such that the list comprises only information on the most suitable access points, for example, on the access points of a certain operator. Thus the access point with the highest priority can be chosen. By means of the embodiment the user terminal is able recognize a certain access point, such as the access point at the working place, and perform a handover to said access point always when entering the coverage area of said access point. In that case the priority of the certain complementary access point is defined higher than the priority of the mobile communications network. The priority of access points may be defined by the user and/or by the operator. For example, the mobile operator may own complementary access points and allow the user terminal to use only these access points as complementary access points by prioritizing these access points.
According to yet another embodiment of the present solution the user terminal is able to store access point information on a new access point, or on an access point with changed data, after registering to the access point. In that case the stored access point information comprises information on cells on the basis of signals received and measured by the user terminal while the user terminal is connected to the access point.
Base stations BS1, BS2, BS3 of the mobile network PLMN transmit 3-4 signals to the user terminal MS. In step 3-5, the user terminal MS receives the transmitted signals, performs signal measurements on the received signals, and, according to the embodiment, compares the signals to the stored access point information. If the measured signals in given boundaries match with the access point information stored in the user terminal MS, (e.g. current cell identity, neighbour cell identity, signal strength, signal quality) it is concluded in the MS that there is a certain available access point AP at the current location of the user terminal MS. If the comparison between the measured mobile signals and the access point information stored in the MS suggest that there is a certain complementary access network, such as a WLAN network, available, the user terminal MS can start to search for the signal from the WLAN access point AP indicated by the access point information, and begin the registration process between the MS and the AP in step 3-3.
The signalling messages and steps shown in
In addition to prior art devices, the system, system nodes or user terminals implementing the operation according to the invention comprise means for storing signal measurement information as described above. The existing network nodes and user terminals comprise processors and memory, which can be used in the functions according to the invention. All the changes needed to implement the invention can be carried out by means of software routines that can be added or updated and/or routines contained in application specific integrated circuits (ASIC) and/or programmable circuits, such as an electrically programmable logic device EPLD or a field programmable gate array FPGA.
It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20045288 | Aug 2004 | FI | national |
