A communication device, also known as User Equipment (UE), mobile station, wireless terminal, receiver and/or mobile terminal is enabled to communicate wirelessly in a wireless communication system, sometimes also referred to as a cellular radio system. The communication may be made e.g. between two communication devices, between a communication device and a wire connected telephone and/or between a communication device and a server via a Radio Access Network (RAN) and possibly one or more core networks.
The communication device may further be referred to as mobile telephone, cellular telephone, computer tablet or laptop with wireless capability. The communication devices in the present context may be, for example, portable, pocket-storable, hand-held, computer-comprised, or vehicle-mounted mobile devices, enabled to communicate voice and/or data, via the radio access network, with another entity, such as another communication device or a server.
The wireless communication system covers a geographical area which is divided into cell areas, with each cell area being served by a radio network node, or base station e.g. a Radio Base Station (RBS), which in some networks may be referred to as transmitter, “eNB”, “eNodeB”, “NodeB” or “B node”, depending on the technology and terminology used. The radio network nodes may be of different classes such as e.g. macro eNodeB, home eNodeB or pico base station, based on transmission power and thereby also cell size. A cell is the geographical area where radio coverage is provided by the radio network node/base station at a base station site. One radio network node, situated on the base station site, may serve one or several cells. The radio network nodes communicate over the air interface operating on radio frequencies with the communication devices within range of the respective radio network node.
In some radio access networks, several radio network nodes may be connected, e.g. by landlines or microwave, to a Radio Network Controller (RNC) e.g. in Universal Mobile Telecommunications System (UMTS). The RNC, also sometimes termed Base Station Controller (BSC) e.g. in Global System for Mobile Communications (GSM), may supervise and coordinate various activities of the plural radio network nodes connected thereto.
In 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) radio network nodes, which may be referred to as eNodeBs or eNBs, may be connected to a gateway e.g. a radio access gateway, to one or more core networks.
In the present context, the expressions downlink, downstream link or forward link may be used for the transmission path from the radio network node to the communication device. The expression uplink, upstream link or reverse link may be used for the transmission path in the opposite direction i.e. from the communication device to the radio network node.
Wireless Fidelity (Wi-Fi), which also may be spelled Wifi, WiFi or WIFI, is a popular technology that allows the communication device to exchange data wirelessly over a computer network, including high-speed Internet connections. The Wi-Fi Alliance defines Wi-Fi as any Wireless Local Area Network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards.
A communication device that is configured to use Wi-Fi such as e.g. a personal computer, video game console, smartphone, tablet, or digital audio player. The communication device in the present context may be, for example, portable, pocket-storable, hand-held, computer-comprised, or vehicle-mounted mobile devices, enabled to communicate voice and/or data, via the radio access network, with another entity, such as another device, a radio network node or a server. The communication device may connect to a network resource such as the Internet via a wireless network access point. Such an access point, or hotspot as it also may be referred to, may have a range of about 20 meters (65 feet) indoors and a greater range outdoors. Hotspot coverage may comprise an area as small as a single room with walls that block radio waves or as large as many square miles, which may be achieved by using multiple overlapping access points.
In a Wi-Fi enabled device, the communication device needs to search for networks to be able to connect, in order to perform e.g. a Voice over the Internet Protocol (VoIP) call.
A communication device may sometimes comprise two or more subscriber identities, such as Subscriber Identity Modules (SIMs). Such a communication device may occasionally be referred to as a Dual SIM phone, or Multiple SIM phone. Each subscriber identity of such communication device may be associated with a modem that is configured for communication over a certain access technology, such as GSM, UMTS, LTE, etc., and/or a VoIP, such as Skype or Google voice.
However, one or more of the subscriber identities may be considered primary subscriber identity and the rest of the subscriber identities are considered secondary subscriber identities. On such a communication device, a mobile originated (outgoing) call is/may be done according to users preferences, e.g. on the subscription with lowest rate or best voice quality.
Generally the user may select which subscriber identity is primary depending on a cost plan.
However, for a mobile terminated, i.e. incoming call, no such choice is possible besides manual call back involving several steps, such as copying the telephone number of the initiator of the incoming call, refusing the incoming call, determining and selecting the best/preferred subscription for call back, entering the noted telephone number of the initiator of the call, call back and wait until the initiating caller response. These manual steps consume time and result in non acceptable delays from a user point of view, especially for the other party, i.e. the initiator of the mobile terminated call.