Abstract: A communication system of the invention includes a communication terminal correctable to first and second communication networks, and a controller for controlling service provision to the communication terminal according to which one of the first and second communication networks the communication terminal is connected to. The communication terminal includes: a reception determination unit for determining a reception condition of a control signal transmitted from the first communication network; and a notification transmitter for transmitting, to the controller, a notification indicating that the control signal can be received when the reception condition satisfies a certain requirement.

Abstract: An apparatus and a method manage a neighbor base station list (NBL) in a distributed wireless ad-hoc network. Information of neighbor BSs is collected at the BS using a surrounding environment detection function. Neighbor BSs that satisfy a certain condition are determined, among the neighbor BSs from which the information is collected. And the NBL is generated based on the determined neighbor BSs.

Abstract: A wireless telephone device, a hand-off method in a wireless telephone device and a communication system are provided to enable the occurrence suppression of instant disconnection in a MAHHO as much as possible. A wireless telephone device (1) includes a communication unit (11) for selecting one of a plurality of frequencies to carry out wireless communication with a base station, a control unit (12) for switching a frequency used by the communication unit (11) to control the communication unit (11) and a speaker for outputting a communication voice in accordance with a voice signal received by the communication unit (11). When the communication unit (11) receives a command to carry out a complement processing for a hand-off candidate frequency during a telephone call, the control unit (12) makes the speaker output a pseudo voice and carries out the complement processing of switching the present frequency in use to the hand-off candidate frequency.

Abstract: A adaptive method implemented by a mobile station improves the likelihood of detecting control messages transmitted to the mobile station in band on a shared downlink traffic channel. When the mobile station expects a control message to be transmitted on the shared downlink traffic channel, the mobile station may adapt the receiver configuration and/or receiver parameters to reduce a likelihood of missed detection of control messages. In one embodiment, the mobile station is configured to adjust a correlation threshold used for said scheduled transmission detection to reduce the likelihood of a missed detection.

Abstract: Network selection techniques for use in a mobile device which is configured for voice and packet data communications are described. The mobile device performs a scanning operation to identify one or more communication networks, and consults a network selection list for selecting, in accordance with assigned priorities of the list, one of the identified networks. The mobile device also determines whether a packet data service interconnection to a home network via the selected network is available. If the interconnection to the home network via the selected network is determined to be available, then the mobile device operates with voice and packet data services in the selected network. Otherwise, if the interconnection to the home network via the selected network is determined to be unavailable, then the mobile device repeats the acts of consulting and determining for the next identified network in the list.

Abstract: Network entities such as an access device and a gateway analyze messages exchanged during a communication session to identify information items of interest such as, for example, email addresses, universal resource locators, file paths, and attachments. References to and/or the contents of the identified information items may be stored in a database that associates the identified information items with the participants of the communication session. The participants in the communication session may be identified by conventional caller ID information, or by an Internet protocol address, an electronic serial number, or a variety of other identifiers. Information received at the beginning of a later communication session that identifies participant(s) in that communication session may then be used to select from the database, information items from previous communication session, that are associated with the identified participant in the current communication session.

Abstract: The present invention discloses a method for processing handover capability and a base station, wherein the method includes: before the Radio network Resource Control Re-establishment (RRC) is initiated in User Equipment (UE), a target base station of a target cell of the UE obtains Closed Subscriber Group (CSG) handover capability of the serving cell from the serving base station; when the RRC connection is in reestablishment, the target base station of the target cell processes the RRC connection reestablishment according to the obtained CSG handover capability. The present invention enables the behavior in UE and in the network keep in alignment after the UE finishes RRC connection reestablishment in the target cell while before it receives the first RRC connection reconfiguration message which is transmitted by the target cell.

Abstract: A method for a cellular system comprising base stations of a first and a second kind, which control cells of a first and second kinds, and a control function for the base station of the first kind. The control function maintains a list of cells in the vicinity of the first cell, a Neighbor Cell list, and a UE in the first cell measures transmissions from Neighbor Cells and reports them, and said UE makes Detected Set, DS, measurements, and reports them to the control function. The control function searches DS measurement reports for cells of the second kind, and if a cell of the second kind is found, a hand over of the UE is initiated, to prevent transmissions from the UE to cause interference in the base station of the second kind.

Abstract: A handover properties estimation system includes a moving-route extraction unit which extracts moving routes which pass through a handover area or a neighboring area by using map information of the handover area and the neighboring area. The handover area is an area in which a handover process occurs between cells in a mobile communication system. The system further includes a moving-route handover properties calculation unit for calculating handover properties of the moving routes extracted by the moving-route extraction unit, by using radio-wave environment information of the moving routes.

Abstract: A handover method according to the present invention includes the steps of: forwarding, at a handover-source radio base station (eNB), user data (A) for a mobile station (UE) to a handover-target radio base station (eNB) when it is determined that a handover processing is to be performed, the user data (A) being stored in the handover-source radio base station (eNB); activating, at the handover-target radio base station, a predetermined timer when transmitting a path switch request to a path control apparatus, and storing second user data for the mobile station received from the path control apparatus until the predetermined timer expires; and forwarding, at the handover-target radio base station, the stored second user data to the mobile station after the predetermined timer expires.

Abstract: An edge monitoring approach can be utilized to detect an attack which includes a plurality of relatively low bandwidth attacks, which are aggregated at a victim sub-network. The aggregated low bandwidth attacks can generate a relatively high bandwidth attack including un-solicited data traffic directed to the victim' so that the aggregated attack becomes more detectable at an edge monitor circuit located proximate to the victim. Related systems, devices, and computer program products are also disclosed.

Abstract: A mobile communication method according to the present invention includes a step of notifying, by a radio base station eNB, a mobile station UE of: a condition under which a measurement report is triggered; a measurement-report target CC having a measurement result that should be reported at the same time when the measurement report is performed; and the maximum number of cells, on the measurement-report target CC, having a measurement result that should be reported, and a step of transmitting, by the mobile station UE, a measurement result of a cell of which the number is equal to or less than the notified maximum number, for each notified measurement-report target CC.

Abstract: The present invention relates to a method of generating neighbor lists in a radio communication network comprising user terminals and base stations defining sectored or omnidirectional radio cells, where communication between user terminals and base stations is arranged to take place over radio channels. The method comprises the steps of: (a) receiving radio channel measurements from at least some of the user terminals; (b) creating a first table by using the measurements received from the user terminals, the first table comprising for at least some of the user terminals the corresponding radio channel measurement in relation to different radio cells; (c) processing the first table to generate a cell coupling matrix indicative of a radio coupling figure between different pairs of cells in the network; and (d) for a certain cell obtaining a neighbor list by determining the radio channel neighbors to be the cells of which the coupling figure with the cell in question is greater than a given threshold.

Abstract: A method of coverage hole compensation is provided in a wireless telecommunications network including a plurality of base station transmitters, each transmitter providing a coverage area for communication with user equipment, wherein a coverage hole is present within a coverage area provided by a transmitting transmitter; the method comprising selecting transmitters which are to be adjusted, including a first dominant transmitter within the coverage hole, and adjusting a transmission parameter of the selected transmitters, wherein the amount of adjustment of the selected first dominant transmitter in the coverage hole is greater than the amount of adjustment of any other selected transmitter.

Abstract: Aspects of mobility management within a wireless communications network including a plurality of sectors are disclosed. In an example, the wireless communications network includes a first cluster of sectors with at least one target sector and at least one supporting sector. The multicast communication session is carried within both the target and supporting sectors. In another example, a second cluster can be included within the network for supporting the same multicast communication session that includes its own target and supporting sectors. In this example, the first cluster transmits multicast media on a first interlace-multiplex (IM) pair of a downlink broadcast channel (BCH) and the second cluster transmits multicast media on a second IM pair of the downlink BCH. If sectors of the first and second clusters are at least adjacent, the network controls a manner in which the first and second clusters carry the multicast media.

Abstract: When communication quality exceeds the first threshold, the radio communication terminal 300 starts connection with the radio communication system 120 and establishes the radio link L2 to the radio communication system 120. Further, a handover from the radio link L1 to the radio link L2 is performed when the communication quality exceeds the second threshold after the establishment of the radio link L2, the second threshold corresponding to communication quality degraded than that indicated by the first threshold.

Abstract: Call handoff from an 802.1x network to a cellular network, and vice versa. A wireless device that has both cellular and 802.1x capability detects the strength of a cellular signal and of an 802.1x signal. If a call is taking place over the 802.1x network and the strength of the 802.1x signal drops below a particular level and the strength of the cellular signal is above a certain level, the call is handed off from the 802.1x network to the cellular network. If a call is taking place over the cellular network and the cellular signal strength drops below a certain level while the 802.1x signal strength is above a certain level, the call is handed off from the cellular network to the 802.1x network. In addition, the user of the wireless device can manually initiate the handoff by actuating a handoff selector of the wireless device.

Abstract: A method and apparatus for reducing handover time includes a wireless transmit receive unit receiving cell specific information in a downlink signal. The downlink signal is one of a set of signals included in a handover process.

Abstract: Provided are a method and an apparatus for power saving of a femto base station operating as a CSG cell in a wireless communication system. A femto base station according to an exemplary embodiment of the present invention includes: a reception unit receiving signals from adjacent second femto base stations; a transmission unit transmitting signals to second femto base stations, and a control unit controlling to be transitioned to an active mode when a mode transition command is received from at least one second femto base station while operating in a sleep mode, in a wireless communication system constituted by a plurality of femto base stations using automatic neighbor relation (ANR).

Abstract: Systems and methods for providing voice communications and data communications are provided, including: receiving an attach message from a mobile node indicating the mobile node can fallback from a first radio access technology to a second radio access technology and including location information identifying a location of the mobile node, the attach message received via the first radio access technology; sending a translated location updated message to a remote switching device; receiving a service request message from the mobile node, the service request message requesting initiation of a voice call, the service request message received via the first radio access technology; and based on the service request message and the indication that the mobile node can fallback to the second radio access technology, setting up the voice call with the mobile node via the second radio access technology.

Abstract: Methods and apparatus for supporting peer to peer communications are described. A plurality of wide area network communications bands in a wireless communications system are also available for use to communicate peer to peer signals. At different times it may be advantageous for a mobile peer to peer communications device to use a different communications band in order to efficiently share air link resources. A peer to peer communications device receives a signal transmitted by a WAN device, e.g., a base station or WAN wireless terminal, and selects a WAN communications band to use as a function of the received signal, e.g., a corresponding band. In some embodiments, the received signal strength measurements from WAN devices are used in the selection process. In other embodiments, recovered decoded information conveyed in a received WAN device signal is used in the selection process.

Abstract: A method and system for performing re-association in a WLAN mesh network are provided. A mobile node transmits authentication request information to an old node via a new node along with a mesh re-association request message for re-association of the mesh network. Upon receiving the mesh re-association request message, the old node performs re-association and authentication according to the mesh re-association request message, and transmits a mesh re-association reply message to the mobile node via the new node.

Abstract: A mobile communications system includes a radio base station and a remote radio apparatus connected with a high-speed transmission medium to the radio base station. A user apparatus includes a unit which measures a received level of a signal transmitted from the radio base station and a received level of a signal transmitted from the remote radio apparatus and detects a change in relative magnitudes of measured values; a unit which measures a path loss between the user apparatus and the radio base station and a path loss between the user apparatus and the remote radio apparatus and detects a change in relative magnitudes of measured values; and a transmitter which transmits a report signal which shows that a predetermined event has occurred. The predetermined event occurs if the relative magnitudes of the received levels are reversed and/or if the relative magnitudes of the path losses are reversed.

Abstract: A femtocell base station 10a suspends transmission and reception of radio waves to and from a radio communication terminal 30 of an accommodation object when the radio communication terminal 30 is not in the neighborhood of the femtocell base station 10a. The femtocell base station 10a determines whether the radio communication terminal 30 is in the neighborhood of the femtocell base station 10a based on information of a UATI update notification provided through another base station in communication with the radio communication terminal 30 and, when the radio communication terminal 30 is in the neighborhood of the femtocell base station 10a, starts receiving the radio waves from the radio communication terminal 30.

Abstract: Successfully decoded data received from a mobile terminal as well as the transmission format of that data is relayed over the backhaul from a base station receiver that successfully decoded the mobile terminal's transmission to the base stations in the mobile terminal's active set that presumably were unable to decode the mobile terminal's transmission due to inadequate signal-to-noise ratio. A base station that receives this transmission from the relaying base station that did'successfully decode and demodulate the mobile terminal's transmission is then able to reconstruct the data and subtract it from the total interference, thereby increasing the signal-to-noise ratio at this base station for its in-cell processing.

Abstract: A method to provide an optimized intra-HeNB GW handover operation that reduces signaling to and from an LTE MME (Mobility Management Entity) function of the 3GPP E-UTRAN Evolved Packet core (EPC). In operation, an HeNB Gateway (GW) intercepts handover requests from a source HeNB to a target HeNB and processes these requests locally, with minimal interaction from the MME. Where possible, messaging to and from the MME is minimized and/or reduced, irrespective of the 3GPP requirement that the GW relay all handover-related messages to the MME.

Abstract: The present invention discloses a method for requesting LTE RRC connection re-establishment and setting cause values as well as a terminal, and the connection re-establishment request method includes: an LTE terminal determines, according to the occurred scenario, which one of the following four types is the failure reason: radio resource failure, handoff failure, bottom layer error or UE-related error; and the LTE terminal initiates an RRC connection re-establishment request to the network side, wherein the RRC connection re-establishment request includes the failure cause value indicating the failure reason. The present invention can make the network side obtain the reason why the UE initiates the RRC re-establishment from RRC connection re-establishment request message, so as to take different subsequent operations with respect to these different failure reasons.

Abstract: A method for a user equipment (UE) operating in a Long Term Evolution network. The method includes the UE receiving a command for a handover from a source cell to a target cell. The method further includes, when the UE has valid stored system information for the target cell, the UE discarding a dedicated radioResourceConfigCommon information element received from the source cell in the handover command and the UE applying radio resource configuration information retrieved from the stored system information.

Abstract: A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires.

Abstract: A network controller including processing circuitry may be configured to receive dynamic position information indicative of a three dimensional position of at least one mobile communication node, compare fixed position information indicative of fixed geographic locations of respective access points of a network to the dynamic position information to determine a relative position of the at least one mobile communication node relative to at least one of the access points based on the fixed position information and the dynamic position information, and provide network control instructions to at least one network asset based on the relative position.

Abstract: When a user equipment (UE) is in a CONNECTED state with a base station of a wireless network and is also in a discontinuous reception (DRX) mode, a DRX parameter such as DRX period for the UE is compared with a threshold. If the DRX parameter is at or below the threshold, the UE applies a network controlled mobility mode with UE assist where the network controls handover of the UE to another cell. If the DRX parameter is above the threshold, the UE applies a UE controlled mobility mode in which the UE is free to select a best cell. In this way, DRX benefit of reduced power consumption is maintained while the time period in which the UE is unreachable is minimized.

Abstract: The invention provides a method of handover from an active network to a selected one of a plurality of potential other networks. In addition to the overall solution, the solution proposed has several individual aspects. All subsidiary aspects are related to the common problem mentioned above and sharing the underlying common solution concept of implementing a system in which selective handover is possible and in which a list of available other networks provided by an active network can be handled and selection made by a terminal, so that neighbor cell information can be transmitted based on expressed terminal preferences.

Abstract: Various systems and methods for interference beacon transmission are disclosed. In one embodiment, an apparatus for initiating cell reselection in a wireless communication device, such as a HNB, comprises a processor configured to determine a first frequency at which one or more wireless communication devices communicate with a first cell and a transceiver configured to transmit an interference beacon at the first frequency configured to at least partially interfere with communications at the first frequency and initiate a cell reselection process by at least one of the wireless communication devices.

Abstract: A method of performing a handover between heterogeneous networks and user equipment apparatus for the same are disclosed. The user equipment apparatus includes a first type communication module configured to transceive a signal with a first type base station (BS) using a first wireless communication scheme, a second type communication module configured to transceive a signal with a second type BS using a second wireless communication scheme, and a processor configured to control the handover to be performed on a second type BS operating in an idle state with the second type communication module when a signal is received from a first type BS operating in an active state with the first type communication module, wherein the signal request that the UE performs the handover to the second type BS operating in an idle state with the second type communication module from the first type BS.

Abstract: Methods and systems for controlling wireless communications are provided. A method of controlling wireless communications includes acquiring base station data at a mobile base station mimicking system. The base station data is associated with a targeted base station of a wireless communication system. The method may include mimicking signals of a neighboring base station of the targeted base station based on the acquired base station data. Further, the method may include transmitting a ban signal associated with the targeted base station. The ban signal is based on the acquired base station data and may induce at least one communication device to stop communicating with the targeted base station. In addition, the method includes controlling communications associated with the at least one communication device via the mobile base station mimicking system.

Abstract: A mobile station device that communicates with a base station device, the mobile station device including: a determination unit which determines whether to request the base station device to provide control information of a small base station device accessed by the mobile station device or not; a first transmission unit, when the determination unit determines that the control information is to be requested, which sets information of the small base station device in a control information request message and transmits the control information request message to the base station device; a first reception unit which receives a response message transmitted from the base station device; and a measurement control execution unit which executes measurement control according to control information set in the response message received by the first reception unit.

Abstract: A mobile communication method according to the present invention is a mobile communication method in which a mobile station is handed over from a cell #B and is subordinate to a radio base station to a cell #C and is subordinate to a radio base station, and includes a step of transmitting “Measurement Configuration” for instructing to measure and report a desired radio quality to the mobile station, a step of transmitting, by the radio base station, “HO Request”, which includes identification information assigned to the cell #B, to the radio base station, a step of transmitting, by the radio base station, “HO Request Ack” including “HO Command” not including “Measurement Configuration” to the radio base station in response to the identification information assigned to the cell #B, and a step of transmitting, by the radio base station, the “HO Command” to the mobile station.

Abstract: Systems and method are presented for a wireless Base Station (BS) of a host Operator to allow access to its Radio Access Network (RAN) by both Subscriber Stations associated with the host Operator and Subscriber Stations associated with other Operators, in which the first set of Subscriber Stations are connected by a general backhaul channel to the host Operator's Core Network data source, and the second set of Subscriber Station are connected by dedicated backhaul channels to Core Network data sources of the other Operators. In this manner, the host Operator provides partial roaming to the second set of Subscriber Stations, which use the host Operators RAN and wireless BS, but not the host Operator's network infrastructure.

Abstract: A method for dual mode mobile terminal in an MIMO wireless communication system is disclosed. The present invention includes the steps of if an uplink transmission mode is for simultaneous transmission to an LTE base station and a CDMA base station, determining whether a transmission power to the LTE base station is equal to or greater than a threshold value, transmitting a simultaneous transmission mode dedicated scheduling request signal for excluding a risky frequency band from an uplink band to the LTE base station, receiving a scheduling information on the uplink band except the risky frequency band from the LTE base station, transmitting a CS service signal to the CDMA base station, and transmitting a PS service signal to the LTE base station using the scheduling information.

Abstract: A cell selection method includes steps of: (A) determining, at a mobile station (UE), whether or not a first CSG cell satisfies a predetermined condition, when using a first macro cell as a camped cell; and (B) changing, at the mobile station (UE), the camped cell from the first macro cell to a first CSG cell, when determined that the first CSG cell satisfies the predetermined condition.

Abstract: Provided is a radio communication system which enables optimal cell switching. A broker femtocell base station is installed in an entrance of the buildings, and sub-femtocell base stations are installed in the buildings. An adjacent cell list and broker femtocell priority selection setting information are set as system information notified from a macro cell, the adjacent cell list including a broker PSC of the broker femtocell base station and PSCs of adjacent macro cells, the broker femtocell priority selection setting information being the information for preferentially selecting the broker femtocell base station. An adjacent cell list and sub-femtocell priority selection setting information are set as system information of the broker femtocell, the adjacent cell list including a PSC of a macro cell, and a sub PSC of an adjacent femtocell, the sub-femtocell priority selection setting information being the information for preferentially selecting the sub-femtocell base station.

Abstract: A mobile communication system has a mobile terminal, basestations, and a Radio Network Controller (RNC). In the case where drop of a frame occurs during data communication in Iub/Iur (between the basestations and the RNC), the RNC executes retransmission of an EDCH FP frame between the RNC and the basestations by transmitting a TN frame to the basestations to repair the drop of the frame without executing retransmission with the terminal device.

Abstract: Disclosed is a method and system for selecting a candidate neighbor cell in the present invention. The method includes: determining a candidate cell set of a serving cell; acquiring a base station closest to the serving cell from the candidate cell set, and adding all the cells under the base station into a neighbor cell set; deleting a cell sheltered by the base station and cells included in the neighbor cell set from the candidate cell set; judging whether the candidate cell set is empty; if not, then returning to the step of acquiring a base station closest to the serving cell; and if yes, then taking cells in the neighbor cell set as a first layer of neighbor cells of the serving cell.

Abstract: A method (700, 800) and apparatus (500, 600) for distinguishing cells with the same physical cell identifier is disclosed. The method can include receiving (820) a handover request message including target cell timing offset information at a potential target cell base station, where the potential target cell base station can have a physical cell identifier. The method can include comparing (830) the received target cell timing offset information with stored timing offset information at the potential target cell base station. The method can include sending (840) a handover request accept message if the received target cell timing offset information is substantially equal to the stored timing offset information. The method can also include receiving (720), at a wireless terminal, a target cell physical cell identifier and determining (730) a target cell timing offset of a radio frame of the target cell with respect to reference timing of a serving cell.

Abstract: An access point for supporting communication in a femto cell of a cellular communication network. The access point comprises transceiver circuitry arranged to enable communication with at least one cell subscribed wireless communication unit located within the femto cell, and signal processing logic module. The signal processing logic is arranged to configure a transmit power level of a Common Pilot CHannel (CPICH) for transmission based at least on cell subscribed wireless communication unit information.

Abstract: A method is provided for controlling an uplink (UL) power by a Mobile Station (MS) in a wireless communication system including an upper-layer Base Station (BS) and a lower-layer BS whose cell coverage is narrower than that of the upper-layer BS.

Abstract: A method and apparatus for handling a call transfer from a circuit switched access network to a packet switched access network. A Mobile Switching Center Server receives a notification that a call for a terminal requires handover from a circuit switched access network to a packet switched access network. The MSC Server determines whether the terminal is currently registered in an IMS network and/or whether the MSC Server is registered such that it can perform handover from the circuit switched access network to the packet switched access network. If so, then return Single Radio Voice Call Continuity is invoked to perform a handover of the call from the circuit switched access network to the packet switched access network. If not then the MSC Server invokes error handling procedures.

Abstract: A first base station forms a cell group including a first cell and a second cell partly overlapping with the first cell. A second base station forms a cell group including a third cell and a fourth cell partly overlapping with the third cell. An allocator of a communication control apparatus specifies an identifier for wireless communication that differs from any of wireless communication identifiers already allocated to mobile devices existing within either the first or second cell forming the cell group, and allocates the specified wireless communication identifier to a mobile device existing in the cell group constituted by the first and second cells. A transmitter transmits the identifier allocated by the allocator to the mobile device via the first base station.

Abstract: Provided is a handover method of a wireless communication system using a hierarchical cellular scheme. In the method, signal quality of a serving node is measured, so that whether to start scanning for a handover is determined. When the scanning for the handover starts, signal qualities of a serving cell including the serving node and one or more neighbor cells are measured through a first preamble including a first identifier for distinguishing a cell. An intra-cell handover or an inter-cell handover is selected using the signal qualities of the serving cell and the neighbor cells. Therefore, a terminal can easily distinguish between the inter-cell handover and the intra-cell handover, and an overhead during a handover can be reduced because an intra-cell handover procedure is simplified.

Abstract: When detecting occurrence of an event for transmitting a measurement report of a radio condition of a cell at a frequency set for a base station apparatus, to the base station apparatus (3) communicating with a terminal apparatus (2), the terminal apparatus (2) in a wireless communication system (1) creates a measurement report including information indicating radio conditions of cells at a frequency at which the event occurred and at another different frequency. The base station apparatus (3) controls whether or not to perform handover of the terminal apparatus (2) to another cell, on the basis of the measurement report transmitted from the terminal apparatus (2). Thereby, there is provided a wireless communication system in which a base station apparatus and the terminal apparatus are communicable with each other using multiple frequencies, the wireless communication system being capable of shortening time required for handover.