Patent Application
20140286322
1. Field of the Invention
The invention generally relates to interworking of heterogeneous radio networks, and more particularly, to assisting a mobile communication device in connecting to an Access Point (AP) when camped on or connected to a base station.
2. Description of the Related Art
With growing demand for ubiquitous computing and networking, various wireless technologies have been developed, such as the Short Range Wireless (SRW) technologies, including the Wireless Fidelity (WiFi) technology, Bluetooth technology, and the ZigBee technology, etc., as well as the telecommunication technologies, including the Global System for Mobile communications (GSM) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for Global Evolution (EDGE) technology, Wideband Code Division Multiple Access (WCDMA) technology, Code Division Multiple Access 2000 (CDMA-2000) technology, Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology, Worldwide Interoperability for Microwave Access (WiMAX) technology, Long Term Evolution (LTE) technology, LTE-Advanced technology, and Time- Division LTE (TD-LTE) technology, etc.
For user convenience and flexibility, most Mobile Stations (MSs) (or may be referred to as User Equipments (UEs)) nowadays are equipped with more than one wireless communication module for supporting different wireless technologies. However, each supported wireless technology has its own features, such as bandwidth, average coverage, and service rate, etc. Particularly, the bandwidth and coverage provided to an MS by a wireless network may vary according to the location conditions of the MS and/or the time conditions.
Taking an MS equipped with a WCDMA module and a WiFi module as an example, it may selectively obtain wireless services using the WCDMA technology and/or the WiFi technology. The wireless services obtained using the WCDMA technology generally have a rather limited bandwidth, but better mobility, while the wireless services obtained using the WiFi technology generally have a sufficient bandwidth, but lack mobility.
Conventionally, the WCDMA module is initially turned on, while the WiFi module is initially turned off and needs to be turned on manually to perform a full scan for every possible AP nearby. Next, the MS may connect to one of the scanned APs, which is determined manually and randomly by the user of the MS or determined automatically by the MS with a previous connection history. That is, the WCDMA system which the MS is connected to via the WCDMA module does not have control over which AP the MS should connect to via the WiFi module. Thus, it is very likely that the connected AP may not have the best channel quality or signal quality, or enough bandwidth among all available APs, or even worse, the connected AP may not be suitable for providing stable services, which would require further connection attempts by the MS to select another AP, thereby causing waste of time and power.
In order to solve the aforementioned problem, the invention proposes base stations, mobile communication devices, and methods for assisting a mobile communication device in connecting to an AP when connected to a base station.
In one aspect of the invention, a base station providing a cellular access service in a cell coverage is provided. The base station comprises a wireless module and a controller module. The wireless module performs wireless transmissions and receptions to and from a mobile communication device using a telecommunication technology. The controller module determines one or more APs providing an SRW service in the cell coverage, selecting one or more APs from the determined APs, and sends access information of the selected APs to the mobile communication device.
In another aspect of the invention, a mobile communication device camped on or connected to a base station is provided. The mobile communication device comprises a first wireless module, a second wireless module, and a controller module. The first wireless module performs wireless transmissions and receptions to and from the base station using a telecommunication technology. The second wireless module performs wireless transmissions and receptions using an SRW technology. The controller module receives access information of one or more APs from the base station via the first wireless module, and scans for only the APs indicated by the access information to connect to one of the scanned APs via the second wireless module.
In yet another aspect of the invention, a method for assisting a mobile communication device in connecting to an AP when camped on or connected to a base station is provided. The method comprises the steps of: determining, by the base station, one or more APs providing an SRW service in a cell coverage of the base station; selecting, by the base station, one or more APs from the determined APs; and sending, by the base station, access information of the selected APs to the mobile communication device.
Other aspects and features of the present invention will become apparent to those with ordinarily skill in the art upon review of the following descriptions of specific embodiments of the base stations, the mobile communication devices, and the methods for assisting a mobile communication device in connecting to an AP when camped on or connected to a base station.
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. It should be understood that the embodiments may be realized in software, hardware, firmware, or any combination thereof.
For example, if the telecommunication network 120 is a WCDMA system, the access network 121 may be a Universal Terrestrial Radio Access Network (UTRAN) which includes at least a Node-B (NB) and a Radio Network Controller (RNC), and the core network 122 may be a General Packet Radio Service (GPRS) core which includes a Home Location Register (HLR), at least one Serving GPRS Support Node (SGSN), and at least one Gateway GPRS Support Node (GGSN). Alternatively, if the telecommunication network 120 is an LTE or LTE-Advanced system, the access network 121 may be an Evolved-UTRAN (E-UTRAN) which includes at least an evolved NB (eNB), and the core network 122 may be an Evolved Packet Core (EPC) which includes a Home Subscriber Server (HSS), Mobility Management Entity (MME), Serving Gateway (S-GW), and Packet Data Network Gateway (PDN-GW or P-GW).
The APs 130 and 140 may each form an SRW network, implemented as alternatives for providing wireless services for the mobile communication device 110. For example, the APs 130 and 140 may be deployed by or operate in cooperation with the operator of the telecommunication network 120 or the partner of the operator of the telecommunication network 120. Specifically, the APs 130 and 140 may connect to a local area network by an Ethernet cable, and they typically receive, buffer, and transmit data traffic which is to be directed to and from the mobile communication device 110. The APs 130 and 140 may be connected to the core network 122 directly or via the Internet, as shown in
To further clarify, each of the wireless modules 10 and 20 may be a respective Radio Frequency (RF) unit, and the controller module 30 may be a general-purpose processor or a Micro Control Unit (MCU) of a baseband unit (not shown). The baseband unit may contain multiple hardware devices to perform baseband signal processing, including analog-to-digital conversion (ADC)/digital-to-analog conversion (DAC), gain adjusting, modulation/demodulation, encoding/decoding, and so on. The RF unit may receive RF wireless signals, convert the received RF wireless signals to baseband signals, which are processed by the baseband unit, or receive baseband signals from the baseband unit and convert the received baseband signals to RF wireless signals, which are later transmitted. The RF unit may also contain multiple hardware devices to perform radio frequency conversion. For example, the RF unit may comprise a mixer to multiply the baseband signals with a carrier oscillated in the radio frequency of the mobile communication system, wherein the radio frequency may be 2.4 GHz, 3.6 GHz, 4.9 GHz, or 5 GHz utilized in WiFi technology, or 900 MHz, 1900 MHz, or 2100 MHz utilized in WCDMA technology, or 900 MHz, 2100 MHz, or 2.6 GHz utilized in LTE/LTE-Advanced technology, or others depending on the wireless technology in use.
Similar to the embodiment of
Next, the base station selects one or more APs from the determined APs (step S320). Specifically, the selecting of APs from the determined APs may be performed according to the traffic loads of the determined APs, the channel qualities of the determined APs, and/or the operation statuses of the determined APs, which each indicates whether a respective one of the determined APs is operative, inoperative, reserved, or unreserved. For example, the selected APs should have corresponding traffic loads lower than a first predetermined threshold, or have corresponding channel qualities greater than a second predetermined threshold, or have corresponding operation statuses indicating that the selected APs are operative and/or unreserved.
After that, the base station sends access information of the selected APs to the mobile communication device (step S330). The access information may contain the Service Set Identifications (SSID) (e.g., BSSID, or ESSID), location information (e.g., latitude and longitude), and used channels of the selected APs. The access information of the selected APs may be sent via a broadcast message or a dedicated message. For example, the access information of the selected APs may be sent in a broadcast message, if the mobile communication device is operating in an idle mode; or the access information of the selected APs may be sent in a dedicated message, if the mobile communication device is operating in a connected mode.
In another embodiment for step S430, the channel qualities of the determined APs may be used instead as the basis for selecting APs, and the selected APs should have corresponding channel qualities greater than a predetermined threshold. In yet another embodiment for step S430, the operation statuses indicating whether the selected APs are operative, inoperative, reserved, or unreserved, may be used instead as the basis for selecting APs, and the selected APs should have corresponding operation statuses indicating that the selected APs are operative and/or unreserved. In still another embodiment for step S430, any combination of the traffic loads, channel qualities, and operation statuses may be used instead as the basis for selecting APs.
Subsequent to step S430, the base station 1211 sorts the selected APs, i.e., the APs 130 and 140, in descending order of their corresponding signal qualities, wherein the descending order prioritizes the selected APs which have greater signal qualities (step S440). In another embodiment for step S440, the base station 1211 may sort the selected APs in ascending order of their corresponding traffic loads, wherein the ascending order prioritizes the selected APs which have lower traffic loads. In yet another embodiment for step S440, the base station 1211 may sort the selected APs in order of their corresponding deployment indicators indicating whether the selected APs are deployed by an operator of the base station 1211 or by the operator's partner, wherein the order prioritizes the selected APs which have corresponding deployment indicators indicating that the selected APs are deployed by the operator of the base station 1211. That is, the operator-deployed APs have higher priorities than the partner-deployed APs. In still another embodiment for step S440, the base station 1211 may use any combination of the traffic loads, signal qualities, and deployment indicators of the selected APs as the basis for sorting the selected APs. For example, the base station 1211 may use the traffic loads as the first basis for sorting the selected APs, and if there are more than one selected APs having the same traffic load, the base station 1211 may then use the deployment indicators as the second basis for sorting the selected APs having the same traffic load, and further if there are more than one selected APs having the same traffic load and deployment indicator, the base station 1211 may then use the signal qualities as the third basis for sorting the selected APs having the same traffic load and deployment indicator.
Please note that, with the sorted ordering resulted from step S440, the base station 1211 does not need to send the information concerning the traffic loads or signal qualities of the selected APs to the mobile communication device 110, thereby saving wireless resources (e.g., channel bandwidth) of the base station 1211.
Subsequent to step S440, the base station 1211 further skims off a predetermined number of the selected APs from the head of the sorted ordering (step S450), and send the access information of the predetermined number of the selected APs, i.e., the skimmed-off APs, to the mobile communication device 110 (S460). In another embodiment, step S450 may be omitted if there's no limitation on the number of APs which the access information thereof is to be sent, i.e., the access information of all of the selected APs may be sent to the mobile communication device 110.
When receiving the access information of the selected APs, the mobile communication device 110 scans for only the APs indicated by the access information to connect to one of the scanned APs (step S470). That is, the mobile communication device 110 does not scan for the APs which are not indicated by the access information, thereby saving power and time for the task of AP scanning.
Upon sending the access information of the skimmed-off APs, the base station 1211 proceeds to determine a repetition frequency for repeating the sending of the access information according to the information concerning whether the skimmed-off APs are deployed in hot spots (e.g., train stations, bus stands, and department stores, etc.), and/or the information concerning whether the current time is rush hour (e.g., 7 am to 9 am, and 5 pm to 7 pm, etc.) (step S480). That is, step S460 may be repeated at the repetition frequency. For example, step S460 may be repeated every 1 second when the skimmed-off APs are deployed in a train station, or every 5 seconds when the skimmed-off APs are deployed in a football stadium (in the off-season). Step S460 may be repeated every 1 second during 7 am to 9 am or every 5 seconds during other times of a day, when the skimmed-off APs are deployed near a bus stand.
While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. Those who are skilled in this technology can still make various alterations and modifications without departing from the scope and spirit of this invention.
Use of ordinal terms such as “first” and “second” in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having the same name (but for use of the ordinal term) to distinguish the claim elements.
This Application claims priority of U.S. Provisional Application No. 61/804,201, filed on Mar. 22, 2013, the entirety of which is incorporated by reference herein. This Application also claims priority of U.S. Provisional Application No. 61/843,212, filed on Jul. 5, 2013, the entirety of which is incorporated by reference herein. This Application claims priority of U.S. Provisional Application No. 61/857,167, filed on Jul. 22, 2013, the entirety of which is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 61804201 | Mar 2013 | US | |
| 61843212 | Jul 2013 | US | |
| 61857167 | Jul 2013 | US |
