Long Term Evolution (LTE) is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by 3rd generation partnership project (3GPP) for enabling high-speed packet communications. After LTE, 5G (fifth generation) New Radio (NR) is a new Radio Access Technology (RAT) developed by 3GPP for the 5G mobile network. The terminology 3GPP Radio Access Technology (RAT) may refer to the RAT promulgated or developed by 3GPP. The User Equipment (UE) is capable of communicating to the network device via the 3GPP RAT and/or the non-3GPP RAT (e.g., the WiFi or the wireless local access network (WLAN)) in the wireless network.
Nowadays, the UE usually faces the handover from the network device to the other network device due to the indoor moving and/or the outdoor transportation. The handover maybe from the 3GPP network device (e.g., a Node-B (NB), an evolved Node-B (eNB), a gNode-B (gNB)) to the other 3GPP network device, from the non-3GPP network device (e.g., the Access Point (AP)) to the other non-3GPP network device, or from the non-3GPP network device to the 3GPP network device, but is not limited herein. The UE cannot transmit and receive data during performing the handover, which causes the throughput drop and the communication interruption.
Therefore, methods for handling the handover to maintain the throughput and to avoid the communication interruption are highly required.
It is an objective of the invention to provide a connection recovery method and an associated communication apparatus, in order to solve the above problem.
An embodiment of the invention provides a communication apparatus comprising a radio transceiver and a modem processor. The radio transceiver is configured to transmit or receive wireless signals in a wireless network. The modem processor is coupled to the radio transceiver and configured to perform operations comprising: connecting to a first network device via a first communication link in a first frequency band; predicting a handover according to at least one of at least one measurement result or location information; connecting to a second network device via a second communication link in a second frequency band, after predicting the handover; performing the handover from the first network device to a third network device, to stop connecting to the first network device and to connect to the third network device via the first communication link in the first frequency band; and stopping connecting to the second network device, after performing the handover.
An embodiment of the invention provides a communication apparatus comprising a radio transceiver and a modem processor. The radio transceiver is configured to transmit or receive wireless signals in a wireless network. The modem processor is coupled to the radio transceiver and configured to perform operations comprising: connecting to a first network device via a first communication link in a first frequency band; predicting a handover according to at least one of at least one measurement result or location information; connecting to a second network device via a second communication link in a second frequency band and not performing a transmission to the first network device, after predicting the handover; performing the handover from the first network to a third network, to stop connecting to the first network device and to connect to the third network device via the first communication link in the first frequency band; and stopping connecting to the second network device, after performing the handover.
These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
The transmitter 111 and the receiver 112 of the radio transceiver 110 may comprise a plurality of hardware devices to perform RF conversion and RF signal processing. For example, the transmitter 111 and/or the receiver 112 may comprise a power amplifier for amplifying the RF signals, a filter for filtering unwanted portions of the RF signals and/or a mixer for performing radio frequency conversion. According to an embodiment of the invention, the radio frequency may be, for example, the frequency of any specific frequency band for a LTE system, or the frequency of any specific frequency band for a 5G NR system, the frequency of any specific frequency band for a WiFi system, etc.
The modem 120 may be configured to handle corresponding communications protocol operations and processing the IF or baseband signals received from or to be transmitted to the radio transceiver 110. The application processor 130 is configured to run the operating system of the communication apparatus 100 and run application programs installed in the communication apparatus 100. In the embodiments of the invention, the modem 120 and the application processor 130 may be designed as discrete chips with some buses or hardware interfaces coupled therebetween, or they may be integrated into a combo chip (i.e., a system on chip (SoC)), and the invention should not be limited thereto.
The subscriber identity card 140 may be a subscriber identity module (SIM), universal mobile telecommunications system (UMTS) SIM (USIM), removable user identity module (R-UIM) or code division multiple access (CDMA) SIM (CSIM) card, or the like and may typically contain user account information, an International Mobile Subscriber Identity (IMSI) and a set of SIM application toolkit (SAT) commands and may provide storage space for phone book contacts. The memory device 150 may be coupled to the modem 120 and application processor 130 and may store system data or user data.
It should be noted that, in order to clarify the concept of the invention,
In some embodiments of the invention, the communication apparatus is capable of supporting multiple radio access technologies (RATs) communications via the single-card structure as shown in
In addition, those who are skilled in this technology can still make various alterations and modifications based on the descriptions given above to derive the communication apparatuses comprising multiple radio transceivers and/or multiple antenna modules for supporting multi-RAT wireless communications without departing from the scope and spirit of this invention. Therefore, in some embodiments of the invention, the communication apparatus may be designed to support a multi-card application, in either a single-standby or a multiple-standby manner, by making some alterations and modifications.
It should be further noted that the subscriber identity card 140 may be dedicated hardware cards as described above, or in some embodiments of the invention, there may be virtual cards, such as individual identifiers, numbers, addresses, or the like which are burned in the internal memory device of the corresponding modem and are capable of identifying the communication apparatus. Therefore, the invention should not be limited to what is shown in the figures.
It should be further noted that in some embodiments of the invention, the communication apparatus may further support multiple IMSIs.
According to an embodiment of the invention, the baseband processing device 221 may be designed to have the capability of handling the baseband signal processing operations for different RATs and processing the corresponding IF or baseband signals in compliance with the corresponding communications protocols, so as to support the multi-RAT wireless communications. According to another embodiment of the invention, the baseband processing device 221 may comprise a plurality of sub-units, each being designed to have the capability of handling the baseband signal processing operations of one or more specific RATs and processing the corresponding IF or baseband signals in compliance with the corresponding communications protocols, so as to support the multi-RAT wireless communications. Therefore, the invention should not be limited to any specific way of implementation.
The modem processor 222 may control the operations of the modem 220. According to an embodiment of the invention, the modem processor 222 maybe arranged to execute the program codes of the corresponding software module of the modem 220. The modem processor 222 may maintain and execute the individual tasks, threads, and/or protocol stacks for different software modules. In an embodiment, a protocol stack may be implemented so as to respectively handle the radio activities of one RAT. However, it is also possible to implement more than one protocol stack to handle the radio activities of one RAT at the same time, or implement only one protocol stack to handle the radio activities of more than one RAT at the same time, and the invention should not be limited thereto.
The modem processor 222 may also read data from the subscriber identity card coupled to the modem, such as the subscriber identity card 140, and write data to the subscriber identity card. The internal memory device 223 may store system data and user data for the modem 220. The modem processor 222 may also access the internal memory device 223.
The network card 224 provides Internet access services for the communication apparatus. It should be noted that, although the network card 224 shown in
It should be noted that, in order to clarify the concept of the invention,
It should be further noted that in some embodiments of the invention, the modem may also comprise more than one processor and/or more than one baseband processing device. For example, the modem may comprise multiple processors and/or multiple baseband processing devices for supporting multi-RAT operations. Therefore, the invention should not be limited to what is shown in
It should be further noted that in some embodiments of the invention, the baseband processing device 221 and the modem processor 222 may be integrated into one processing unit, and the modem may comprise one or multiple such processing units, for supporting multi-RAT operations. Therefore, the invention should not be limited to what is shown in
According to an embodiment of the invention, the modem processor 222 and the application processor 130 may comprise a plurality of logics, each, designed for handling one or more functionalities. The logics maybe configured to execute the program codes of one or more software and/or firmware modules, thereby performing the corresponding operations. When performing the corresponding operations by executing the corresponding programs, the logics may be regarded as dedicated hardware devices or circuits, such as dedicated processor sub-units. Generally, the modem processor 222 may be configured to perform operations of relative lower protocol layers while the application processor 130 may be configured to perform operations of relative higher protocol layers. Therefore, in some embodiments of the invention, the application processor 130 may be regarded as the upper layer entity or upper layer processing circuit with respect to the modem processor 222 and the modem processor 222 maybe regarded as the lower layer entity or lower layer processing circuit with respect to the application processor 130.
Step S300:Start.
Step S302:Connecting to a first network device via a first communication link in a first frequency band.
Step S304:Predicting the handover according to at least one of at least one measurement result or location information.
Step S306:Connecting to a second network device via a second communication link in a second frequency band, after predicting the handover.
Step S308:Performing the handover from the first network device to a third network device, to stop connecting to the first network device and to connect to the third network device via the first communication link in the first frequency band.
Step S310:Stopping connecting to the second network device, after performing the handover.
Step S312:End.
Realization of the process 30 is not limited to the above description. The following embodiments of the invention may be applied to realize the process 30.
In an embodiment of the invention, first data transmitted via the first communication link is the same as second data transmitted via the second communication link. In an embodiment of the invention, first data transmitted via the first communication link is different from second data transmitted via the second communication link.
Step S600:Start.
Step S602:Connecting to a first network device via a first communication link in a first frequency band.
Step S604:Predicting the handover according to at least one of at least one measurement result or location information.
Step S606:Connecting to a second network device via a second communication link in a second frequency band and not performing a transmission to the first network device, after predicting the handover.
Step S608:Performing the handover from the first network to a third network, to stop connecting to the first network device and to connect to the third network device via the first communication link in the first frequency band.
Step S610:Stopping connecting to the second network device, after performing the handover.
Step S612:End.
Realization of the process 60 is not limited to the above description. The following embodiment of the invention may be applied to realize the process 60.
In an embodiment of the invention, first data transmitted via the first communication link is different from second data transmitted via the second communication link.
The following embodiments of the invention may be applied to realize the processes 30 and 60.
In an embodiment of the invention, a first SIM in the communication apparatus for connecting to the first network device and the third network device is different from a second SIM in the communication apparatus for connecting to the second network device. In the case of the embodiment applied to the process 30, the communication apparatus transmits the first data via the first SIM and the second data via the second SIM (e.g., at the same time), after predicting the handover. In the case of the embodiment applied to the process 60, the communication apparatus switches from the first SIM to the second SIM after predicting the handover, and switches from the second SIM to the first SIM after performing the handover. In an embodiment of the invention, a first mobile network operation (MNO) of the first SIM is different from a second MNO of the second SIM. In an embodiment of the invention, the first MNO of the first SIM is the same as the second MNO of the second SIM.
In an embodiment of the invention, the communication apparatus predicts the handover according to at least one behavior of the communication apparatus related to the second SIM. In an embodiment of the invention, the at least one behavior of the communication apparatus related to the second SIM comprises a reception (e.g., a discontinuous reception (DRX), a paging reception, a system information block (SIB) reception) performed via the second SIM, a cell reselection performed via the second SIM and/or data transmissions/receptions (e.g., a tracking area update (TAU) procedure and/or a mobility registration update (MRU) procedure) performed via the second SIM. In an embodiment of the invention, the communication apparatus predicts the handover according to a measurement gap of a measurement (e.g., performed via the first SIM). That is, the handover is predicted by the communication apparatus according to a communication interruption event.
In an embodiment of the invention, the communication apparatus predicts the handover according to a measurement event. For example, the communication apparatus knows that the handover from the first network device to the third network device will occur, when a measurement event A3 (e.g., a cell of the third network device has a better performance than a cell of the first network device) is reported. That is, the handover is predicted by the communication apparatus according to a history/statistics of handover events.
In an embodiment of the invention, the at least one measurement result comprises at least one of a measurement result of a radio quality, at least one first measurement result of the first network device, at least one second measurement result of the second network device or at least one third measurement result of the third network device. In an embodiment of the invention, the at least one first measurement result comprises at least one measurement result of signal power of the first network device. In an embodiment of the invention, the at least one second measurement result comprises a measurement result of intra/inter-frequency neighbor network devices (e.g., measured via the second SIM) and/or a measurement result of inter-RAT neighbor network devices (e.g., measured via the second SIM). In an embodiment of the invention, the at least one third measurement result comprises a measurement result of inter-frequency neighbor network devices (e.g., measured via the first SIM) and/or a measurement result of inter-RAT neighbor network devices (e.g., measured via the first SIM).
In an embodiment of the invention, the communication apparatus obtains the location information related to at least one of the communication apparatus, the first network device, the second network device or the third network device according to at least one of a sensor of the communication apparatus or a database of a network device map. That is, the handover is predicted by the communication apparatus according to location(s) of the communication apparatus, the first network device, the second network device and/or the third network device.
In an embodiment of the invention, the communication apparatus predicts the handover according to a first thread of the communication apparatus. A second thread of other communication apparatus records signal strength information of signals received from network devices (e.g., the first network device and the third network device in the processes 30 and 60), and transmits the signal strength information to nearby threads. The nearby threads are located at edges of coverage areas of the network devices, and store the signal strength information. The nearby threads transmit the signal strength information to the first thread of the communication apparatus, when the communication apparatus is in the coverage areas of the network devices. That is, the handover is predicted by the communication apparatus according to the signal strength information received by the first thread of the communication apparatus. In an embodiment of the invention, the network devices may be APs or AP routers.
In an embodiment of the invention, the first network device is a NB or an AP. In an embodiment of the invention, the second network device is a NB or an AP. In an embodiment of the invention, the third network device is a NB, an AP or a null network device. In an embodiment of the invention, a coverage area of the null network device is an area without any signal (e.g., WiFi signal). In an embodiment of the invention, the wireless network comprises a cellular network and/or a wireless local area network (WLAN) (e.g., WiFi).
To sum up, the present invention provides a communication apparatus and a method for handling a handover in a wireless network. The communication apparatus predicts the handover from the first network device to the third network device via the first communication link, and connects to the second network device via the second communication link. Therefore, the problem of handling the handover to maintain the throughput and to avoid the communication interruption can be solved.
Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.
This application claims the benefit of U.S. Provisional Application No. 63/217,423, filed on Jul. 1, 2021. The content of the application is incorporated herein by reference.
Number | Date | Country | |
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63217423 | Jul 2021 | US |