FORM 2
THE PATENTS ACT, 1970 (39 OF
1970)
&
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
“METHOD AND SYSTEM FOR PERFORMING HANDOVER IN A WIRELESS
COMMUNICATION NETWORK”
We, Jio Platforms Limited, an Indian National, of Office - 101, Saffron, Nr. Centre Point,
Panchwati 5 Rasta, Ambawadi, Ahmedabad - 380006, Gujarat, India.
The following specification particularly describes the invention and the manner in which it is
to be performed.
2
METHOD AND SYSTEM FOR PERFORMING HANDOVER IN A WIRELESS
COMMUNICATION NETWORK
FIELD OF INVENTION
5
[0001] Embodiments of the present disclosure generally relate to wireless communication.
More particularly, embodiments of the present disclosure relate to method and system for
performing handover in a wireless communication network.
10 BACKGROUND
[0002] The following description of the related art is intended to provide background
information pertaining to the field of the disclosure. This section may include certain aspects
of the art that may be related to various features of the present disclosure. However, it should
15 be appreciated that this section is used only to enhance the understanding of the reader with
respect to the present disclosure, and not as admissions of the prior art.
[0003] Wireless communication technology has rapidly evolved over the past few decades,
with each generation bringing significant improvements and advancements. The first
20 generation of wireless communication technology was based on analog technology and offered
only voice services. However, with the advent of the second generation (2G) technology,
digital communication and data services became possible, and text messaging was introduced.
The third generation (3G) technology marked the introduction of high-speed internet access,
mobile video calling, and location-based services. The fourth generation (4G) technology
25 revolutionized wireless communication with faster data speeds, better network coverage, and
improved security. Currently, the fifth generation (5G) technology is being deployed,
promising even faster data speeds, low latency, and the ability to connect multiple devices
simultaneously. With each generation, wireless communication technology has become more
advanced, sophisticated, and capable of delivering more services to its users.
30
[0004] In wireless communication, handover occurs when a user equipment (UE) moves from
its serving cell to a second cell during an ongoing voice or data transmission. The ongoing
voice or data transmission is transferred from the channel of the serving cell to the channel of
the second cell. Handover failure is a common problem that can result in degraded network
3
performance and poor user experience. The root cause of handover failure can be complex and
multifaceted, involving issues with hardware and software, network configuration, and radio
access network (RAN) design.
5 [0005] Further, over the period of time various solutions have been developed to improve the
performance of communication devices and to enhance the user experience in 5G network by
intelligent handover mechanism. However, there are certain challenges with existing solutions.
In the existing solutions, handover is done via Xn or Ng interface explicitly. The Xn or Ng
interface are the interfaces between two adjacent gNBs in the 5G communication network. This
10 interface facilitates the transfer of user data and control signalling during handover procedures,
thereby allowing seamless mobility of the user devices between different cell sites served by
adjacent gNBs. The Xn interface is responsible for enabling coordination and synchronization
between gNBs to ensure uninterrupted connectivity and quality of service for mobile users
undergoing handover situations. While the Ng interface plays a crucial role in facilitating
15 communication between the radio access network (RAN) and the core network for the
establishment, management, and optimization of user sessions in 5G networks.
[0006] There may be certain situations in which the Xn or Ng interface is established from the
source base station/ source/ gNB (i.e., the gNB from which handover is to be done) but the
20 interface is down from the target base station/ target/ gNB (i.e., the gNB to which handover is
to be done). The existing solutions fail to provide quick handover to UE in a scenario where
handover is getting stuck or failing due to such reasons, thus resulting in poor user experience.
[0007] Therefore, there exists an imperative need in the art to enhance the user experience in
25 5G by intelligent handover mechanism, which the present disclosure aims to address.
SUMMARY OF THE DISCLOSURE
30 [0008] This section is provided to introduce certain aspects of the present disclosure in a
simplified form that are further described below in the detailed description. This summary is
not intended to identify the key features or the scope of the claimed subject matter.
4
[0009] An aspect of the present disclosure may relate to a method for performing handover in
a wireless communication network. The method comprises identifying, by an identification
unit, a first interface between a source base station and a target base station. The method further
comprises transmitting, by a transceiver unit, a handover request for a user equipment (UE)
5 from the source base station to the target base station based on a measurement report received
at the source base station from the UE. The method further comprises, receiving, via the
transceiver unit at the source base station, a handover response from the target base station
based on the handover request for the UE. The method further comprises, detecting, by a
handover manager unit, a failure of the handover of the UE between the source base station
10 and the target base station, via the first interface based on the handover response. And, the
method further comprises, performing, by the handover manager unit, the handover of the UE
between the source base station and the target base station via a second interface based at least
on the detection of failure of the handover of the UE between the source base station and the
target base station via the first interface.
15
[0010] In an exemplary aspect of the present disclosure, in the disclosed method, the source
base station is a source next-generation Node Base station (source gNB) from which the
handover of the UE is to be done and the target base station is a target next-generation Node
Base station (target gNB) to which the handover of the UE is to be done.
20
[0011] In an exemplary aspect of the present disclosure, in the disclosed method, the first
interface is an Xn interface, and the second interface is a Ng interface.
[0012] In an exemplary aspect of the present disclosure, the method further comprises,
25 detecting, by the handover manager unit, a failure of the handover of the UE between the source
base station and the target base station via the first interface and the second interface. The
method further comprises blacklisting, by the handover manager unit, the target base station
for a pre-defined time period, based on the detection of the failure of the handover of the UE
between the source base station and the target base station via the first interface and the second
30 interface. And, the method further comprises stopping, by the handover manager unit, the
handover of the UE and one or more other UEs to the target base station for the pre-defined
time period based on the blacklisting.
5
[0013] In an exemplary aspect of the present disclosure, performing, by the handover manager
unit, the handover of the UE between the source base station and the target base station via the
second interface, is further based on the detection of the failure of the handover of the UE
between the source base station and the target base station via the first interface for more than
5 a predefined number of times.
[0014] Another aspect of the present disclosure may relate to a system for performing handover
in a wireless communication network. The system comprises an identification unit configured
to identify a first interface between a source base station and a target base station. The system
10 further comprises a transceiver unit connected at least to the identification unit. The transceiver
unit is configured to transmit, a handover request for a user equipment (UE) from the source
base station to the target base station based on a measurement report received at the source
base station from the UE. The transceiver unit is configured to receive, at the source base
station, a handover response from the target base station based on the handover request for the
15 UE. The system further comprises a handover manager unit connected at least to the transceiver
unit and the identification unit. The handover manager unit is configured to detect a failure of
the handover of the UE between the source base station and the target base station, via the first
interface based on the handover response. The handover manger unit is further configured to
perform the handover of the UE between the source base station and the target base station via
20 a second interface based at least on the detection of failure of the handover of the UE between
the source base station and the target base station via the first interface.
[0015] Yet another aspect of the present disclosure may relate to a non-transitory computer
readable storage medium storing instructions for performing handover in a wireless
25 communication network, the instructions include executable code which, when executed by a
one or more units of a system, causes: an identification unit to identify a first interface between
a source base station and a target base station; a transceiver unit to transmit, a handover request
for a user equipment (UE) from the source base station to the target base station based on a
measurement report received at the source base station from the UE, and to receive, at the
30 source base station, a handover response from the target base station based on the handover
request for the UE; a handover manager unit configured to detect a failure of the handover of
the UE between the source base station and the target base station, via the first interface based
on the handover response, and to perform the handover of the UE between the source base
station and the target base station via a second interface based at least on the detection of failure
6
of the handover of the UE between the source base station and the target base station via the
first interface.
[0016] Yet another aspect of the present disclosure may relate to a User Equipment (UE) in a
5 wireless communication network. The UE comprises a transceiver unit which is configured to
send a request to a system for performing the handover from a source base station to a target
base station. The transceiver unit is further configured to transmit a measurement report to the
source base station. The UE is then handed off to the target base station based on a handover
response received from the system. It is to be noted that the handoff between the source base
10 station and the target base station happens via at least one of an Xn interface and a Ng interface.
OBJECTS OF THE DISCLOSURE
[0017] Some of the objects of the present disclosure, which at least one embodiment disclosed
15 herein satisfies are listed herein below.
[0018] It is an object of the present disclosure to provide a system and a method for performing
intelligent handover for improving the user experience in 5G.
20 [0019] It is another object of the present disclosure to provide a solution that performs reliable
handover procedure when Xn interface is down at any end on either side of gNB.
[0020] It is yet another object of the present disclosure to provide a solution to perform quick
handover whenever required after triggering the measurement configuration.
25
DESCRIPTION OF THE DRAWINGS
[0021] The accompanying drawings, which are incorporated herein, and constitute a part of
this disclosure, illustrate exemplary embodiments of the disclosed methods and systems in
30 which like reference numerals refer to the same parts throughout the different drawings.
Components in the drawings are not necessarily to scale, emphasis instead being placed upon
clearly illustrating the principles of the present disclosure. Also, the embodiments shown in the
figures are not to be construed as limiting the disclosure, but the possible variants of the method
and system according to the disclosure are illustrated herein to highlight the advantages of the
7
disclosure. It will be appreciated by those skilled in the art that disclosure of such drawings
includes disclosure of electrical components or circuitry commonly used to implement such
components.
5 [0022] FIG.1 illustrates an exemplary block diagram representation of 5th generation core
(5GC) network architecture with multiple interfaces for performing handover, in accordance
with exemplary embodiments of the present disclosure.
[0023] FIG. 2 illustrates an exemplary block diagram of a computing device upon which the
10 features of the present disclosure may be implemented in accordance with exemplary
implementation of the present disclosure.
[0024] FIG. 3 illustrates an exemplary block diagram of a system for performing handover in
a wireless communication network, in accordance with exemplary implementations of the
15 present disclosure.
[0025] FIG. 4 illustrates a method flow diagram for performing handover in a wireless
communication network, in accordance with exemplary implementations of the present
disclosure.
20
[0026] FIG.5 illustrates an exemplary flow diagram indicating the process for performing
intelligent handover for enhancing the user experience during mobility, in accordance with
exemplary embodiments of the present disclosure.
25 [0027] FIG.6 illustrates an exemplary method flow diagram indicating the process for
performing intelligent handover for enhancing the user experience during mobility, in
accordance with exemplary embodiments of the present disclosure.
[0028] The foregoing shall be more apparent from the following more detailed description of
30 the disclosure.
DETAILED DESCRIPTION
8
[0029] In the following description, for the purposes of explanation, various specific details
are set forth in order to provide a thorough understanding of embodiments of the present
disclosure. It will be apparent, however, that embodiments of the present disclosure may be
practiced without these specific details. Several features described hereafter may each be used
5 independently of one another or with any combination of other features. An individual feature
may not address any of the problems discussed above or might address only some of the
problems discussed above.
[0030] The ensuing description provides exemplary embodiments only, and is not intended to
10 limit the scope, applicability, or configuration of the disclosure. Rather, the ensuing description
of the exemplary embodiments will provide those skilled in the art with an enabling description
for implementing an exemplary embodiment. It should be understood that various changes may
be made in the function and arrangement of elements without departing from the spirit and
scope of the disclosure as set forth.
15
[0031] Specific details are given in the following description to provide a thorough
understanding of the embodiments. However, it will be understood by one of ordinary skill in
the art that the embodiments may be practiced without these specific details. For example,
circuits, systems, processes, and other components may be shown as components in block
20 diagram form in order not to obscure the embodiments in unnecessary detail.
[0032] Also, it is noted that individual embodiments may be described as a process which is
depicted as a flowchart, a flow diagram, a data flow diagram, a structure diagram, or a block
diagram. Although a flowchart may describe the operations as a sequential process, many of
25 the operations may be performed in parallel or concurrently. In addition, the order of the
operations may be re-arranged. A process is terminated when its operations are completed but
could have additional steps not included in a figure.
[0033] The word “exemplary” and/or “demonstrative” is used herein to mean serving as an
30 example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed
herein is not limited by such examples. In addition, any aspect or design described herein as
“exemplary” and/or “demonstrative” is not necessarily to be construed as preferred or
advantageous over other aspects or designs, nor is it meant to preclude equivalent exemplary
structures and techniques known to those of ordinary skill in the art. Furthermore, to the extent
9
that the terms “includes,” “has,” “contains,” and other similar words are used in either the
detailed description or the claims, such terms are intended to be inclusive—in a manner similar
to the term “comprising” as an open transition word—without precluding any additional or
other elements.
5
[0034] As used herein, a “processing unit” or “processor” or “operating processor” includes
one or more processors, wherein processor refers to any logic circuitry for processing
instructions. A processor may be a general-purpose processor, a special purpose processor, a
conventional processor, a digital signal processor, a plurality of microprocessors, one or more
10 microprocessors in association with a (Digital Signal Processing) DSP core, a controller, a
microcontroller, Application Specific Integrated Circuits, Field Programmable Gate Array
circuits, any other type of integrated circuits, etc. The processor may perform signal coding
data processing, input/output processing, and/or any other functionality that enables the
working of the system according to the present disclosure. More specifically, the processor or
15 processing unit is a hardware processor.
[0035] As used herein, “a user equipment”, “a user device”, “a smart-user-device”, “a smartdevice”, “an electronic device”, “a mobile device”, “a handheld device”, “a wireless
communication device”, “a mobile communication device”, “a communication device” may
20 be any electrical, electronic and/or computing device or equipment, capable of implementing
the features of the present disclosure. The user equipment/device may include, but is not limited
to, a mobile phone, smart phone, laptop, a general-purpose computer, desktop, personal digital
assistant, tablet computer, wearable device or any other computing device which is capable of
implementing the features of the present disclosure. Also, the user device may contain at least
25 one input means configured to receive an input from at least one of a transceiver unit, a
processing unit, a storage unit, a detection unit and any other such unit(s) which are required
to implement the features of the present disclosure.
[0036] As used herein, “storage unit” or “memory unit” refers to a machine or computer30 readable medium including any mechanism for storing information in a form readable by a
computer or similar machine. For example, a computer-readable medium includes read-only
memory (“ROM”), random access memory (“RAM”), magnetic disk storage media, optical
storage media, flash memory devices or other types of machine-accessible storage media. The
10
storage unit stores at least the data that may be required by one or more units of the system to
perform their respective functions.
[0037] As used herein “interface” or “user interface refers to a shared boundary across which
5 two or more separate components of a system exchange information or data. The interface may
also be referred to a set of rules or protocols that define communication or interaction of one
or more modules or one or more units with each other, which also includes the methods,
functions, or procedures that may be called.
10 [0038] All modules, units, components used herein, unless explicitly excluded herein, may be
software modules or hardware processors, the processors being a general-purpose processor, a
special purpose processor, a conventional processor, a digital signal processor (DSP), a
plurality of microprocessors, one or more microprocessors in association with a DSP core, a
controller, a microcontroller, Application Specific Integrated Circuits (ASIC), Field
15 Programmable Gate Array circuits (FPGA), any other type of integrated circuits, etc.
[0039] As used herein the transceiver unit includes at least one receiver and at least one
transmitter configured respectively for receiving and transmitting data, signals, information or
a combination thereof between units/components within the system and/or connected with the
20 system.
[0040] As discussed in the background section, the current known solutions for performing
handover using Xn interface have several shortcomings. The handover fails if the Xn interface
is down at the target base station when the source base station tries to establish the interface.
25 The present disclosure aims to overcome the above-mentioned and other existing problems in
this field of technology by providing method and system of performing handover in a wireless
communication network.
[0041] FIG. 1 illustrates an exemplary block diagram representation of 5th generation core
30 (5GC) network architecture, in accordance with exemplary implementation of the present
disclosure. As shown in FIG. 1, the 5GC network architecture [100] includes a user equipment
(UE) [102], a radio access network (RAN) [104], an access and mobility management function
(AMF) [106], a Session Management Function (SMF) [108], a Service Communication Proxy
(SCP) [110], an Authentication Server Function (AUSF) [112], a Network Slice Specific
11
Authentication and Authorization Function (NSSAAF) [114], a Network Slice Selection
Function (NSSF) [116], a Network Exposure Function (NEF) [118], a Network Repository
Function (NRF) [120], a Policy Control Function (PCF) [122], a Unified Data Management
(UDM) [124], an application function (AF) [126], a User Plane Function (UPF) [128], a data
5 network (DN) [130], wherein all the components are assumed to be connected to each other in
a manner as obvious to the person skilled in the art for implementing features of the present
disclosure.
[0042] Radio Access Network (RAN) [104] is the part of a mobile telecommunications system
10 that connects user equipment (UE) [102] to the core network (CN) and provides access to
different types of networks (e.g., 5G network). It consists of radio base stations such as but not
limited to RAN 1 and RAN 2 which represent source base station (source gNB) and target base
station (target gNB) respectively, connected to the AMF [106] via the N2/ Ng interface which
supports control plane signalling between RAN1, RAN2 and 5G core for UE context
15 management. It is to be noted that N2 or Ng interface have been used interchangeably and bear
the same meaning when it comes to carrying out the present disclosure in the exemplary
embodiment. It is further noted that the handover of the UE [102] from RAN 1 (the source base
station) to RAN 2 (the target base station) via the Ng interface (second interface) is based on
the detection of failure of the handover of the UE [102] between the source base station and
20 the target base station via the Xn interface (first interface).
[0043] It is further noted that the description for rest of the components of the 5GC network
architecture as shown in FIG. 1, such as AMF [106], SMF [108], SCP [110], AUSF [112],
NSSAAF [114], NSSF [116], NEF [118], NRF [120], PCF [122], UDM [124], AF [126], UPF
25 [128], DN [130] of a conventional 5G network architecture are obvious to a person skilled in
the art.
[0044] FIG. 2 illustrates an exemplary block diagram of a computing device [200] (also
referred to herein as a computer system [200]) upon which the features of the present disclosure
30 may be implemented in accordance with exemplary implementation of the present disclosure.
In an implementation, the computing device [200] may also implement a method for
performing handover in a wireless communication network utilising the system. In another
implementation, the computing device [200] itself implements the method for performing
handover in a wireless communication network using one or more units configured within the
12
computing device [200], wherein said one or more units are capable of implementing the
features as disclosed in the present disclosure.
[0045] The computing device [200] may include a bus [202] or other communication
5 mechanism for communicating information, and a hardware processor [204] coupled with bus
[202] for processing information. The hardware processor [204] may be, for example, a
general-purpose microprocessor. The computing device [200] may also include a main memory
[206], such as a random-access memory (RAM), or other dynamic storage device, coupled to
the bus [202] for storing information and instructions to be executed by the processor [204].
10 The main memory [206] also may be used for storing temporary variables or other intermediate
information during execution of the instructions to be executed by the processor [204]. Such
instructions, when stored in non-transitory storage media accessible to the processor [204],
render the computing device [200] into a special-purpose machine that is customized to
perform the operations specified in the instructions. The computing device [200] further
15 includes a read only memory (ROM) [208] or other static storage device coupled to the bus
[202] for storing static information and instructions for the processor [204].
[0046] A storage device [210], such as a magnetic disk, optical disk, or solid-state drive is
provided and coupled to the bus [202] for storing information and instructions. The computing
20 device [200] may be coupled via the bus [202] to a display [212], such as a cathode ray tube
(CRT), Liquid crystal Display (LCD), Light Emitting Diode (LED) display, Organic LED
(OLED) display, etc. for displaying information to a computer user. An input device [214],
including alphanumeric and other keys, touch screen input means, etc. may be coupled to the
bus [202] for communicating information and command selections to the processor [204].
25 Another type of user input device may be a cursor controller [216], such as a mouse, a trackball,
or cursor direction keys, for communicating direction information and command selections to
the processor [204], and for controlling cursor movement on the display [212]. This input
device typically has two degrees of freedom in two axes, a first axis (e.g., x) and a second axis
(e.g., y), that allow the device to specify positions in a plane.
30
[0047] The computing device [200] may implement the techniques described herein using
customized hard-wired logic, one or more ASICs or FPGAs, firmware and/or program logic
which in combination with the computing device [200] causes or programs the computing
device [200] to be a special-purpose machine. According to one implementation, the techniques
13
herein are performed by the computing device [200] in response to the processor [204]
executing one or more sequences of one or more instructions contained in the main memory
[206]. Such instructions may be read into the main memory [206] from another storage
medium, such as the storage device [210]. Execution of the sequences of instructions contained
5 in the main memory [206] causes the processor [204] to perform the process steps described
herein. In alternative implementations of the present disclosure, hard-wired circuitry may be
used in place of or in combination with software instructions.
[0048] The computing device [200] also may include a communication interface [218] coupled
10 to the bus [202]. The communication interface [218] provides a two-way data communication
coupling to a network link [220] that is connected to a local network [222]. For example, the
communication interface [218] may be an integrated services digital network (ISDN) card,
cable modem, satellite modem, or a modem to provide a data communication connection to a
corresponding type of telephone line. As another example, the communication interface [218]
15 may be a local area network (LAN) card to provide a data communication connection to a
compatible LAN. Wireless links may also be implemented. In any such implementation, the
communication interface [218] sends and receives electrical, electromagnetic or optical signals
that carry digital data streams representing various types of information.
20 [0049] The computing device [200] can send messages and receive data, including program
code, through the network(s), the network link [220] and the communication interface [218].
In the Internet example, a server [230] might transmit a requested code for an application
program through the Internet [228], the ISP [226], the host [224] the local network [222] and
the communication interface [218]. The received code may be executed by the processor [204]
25 as it is received, and/or stored in the storage device [210], or other non-volatile storage for later
execution.
[0050] Referring to FIG. 3, an exemplary block diagram of a system [300] for performing
handover in a wireless communication network, is shown, in accordance with the exemplary
30 implementations of the present disclosure. The system [300] comprises at least one
identification unit [302], at least one first interface [305f], at least one second interface [305s],
at least one transceiver unit [306] and at least one handover manager unit [307]. Also, all the
components/ units of the system [300] are assumed to be connected to each other unless
otherwise indicated below. As shown in the FIG. 3, all units shown within the system should
14
also be assumed to be connected to each other. Also, in FIG. 3 only a few units are shown,
however, the system [300] may comprise multiple such units or the system [300] may comprise
any such numbers of said units, as required to implement the features of the present disclosure.
Further, in an implementation, the system [300] may be present in a user device to implement
5 the features of the present disclosure. The system [300] may be a part of the user device / or
may be independent of but in communication with the user device [(may also referred herein
as a user equipment (UE) [303]. In another implementation, the system [300] may reside in a
source base station [304s]. In another implementation, the system [300] may reside in a target
base station [304t]. In another implementation, the system [300] may reside in a server or a
10 network entity. In yet another implementation, the system [300] may reside partly in the server/
network entity and partly in the user equipment [303].
[0051] Further, in accordance with the present disclosure, it is to be acknowledged that the
functionality described for the various the components/units can be implemented
15 interchangeably. While specific embodiments may disclose a particular functionality of these
units for clarity, it is recognized that various configurations and combinations thereof are
within the scope of the disclosure. The functionality of specific units as disclosed in the
disclosure should not be construed as limiting the scope of the present disclosure.
Consequently, alternative arrangements and substitutions of units, provided they achieve the
20 intended functionality described herein, are considered to be encompassed within the scope of
the present disclosure.
[0052] The system [300] is configured for performing handover in a wireless communication
network, with the help of the interconnection between the components/units of the system
25 [300]. In another implementation of the present disclosure, the system [300] is configured for
enhancing the user experience during mobility of the UE [303].
[0053] The identification unit [302] is configured to identify, the first interface [305f] between
the source base station [304s] and the target base station [304t].
30
[0054] The transceiver unit [306] connected to at least the identification unit [302], the
transceiver unit [306] is configured to transmit, a handover request for the UE [303] from the
source base station [304s] to the target base station [304t] based on a measurement report
received at the source base station [304s] from the UE [303]. The transceiver unit [306] is
15
further configured to receive, at the source base station [304s], a handover response from the
target base station [304t] based on the handover request for the UE [303].
[0055] The handover manager unit [307] connected to at least the transceiver unit [306] and
5 the identification unit [302], the handover manager unit [307] is configured to detect a failure
of the handover of the UE [303] between the source base station [304s] and the target base
station [304t], via the first interface [305f] based on the handover response. The handover
manger unit [307] is further configured to perform the handover of the UE [303] between the
source base station [304s] and the target base station [304t] via a second interface [305s] based
10 at least on the detection of the failure of the handover of the UE [303] between the source base
station [304s] and the target base station [304t] via the first interface [305f].
[0056] In an exemplary embodiment of the present disclosure, the source base station [304s]
is a source next-generation Node Base station (source gNB) from which the handover of the
15 UE [303] is to be done and the target base station [304t] is a target next-generation Node Base
station (target gNB) to which the handover of the UE [303] is to be done.
[0057] In an exemplary embodiment of the present disclosure, the first interface [305f] is an
Xn interface, and the second interface [305s] is a Ng interface.
20
[0058] In an exemplary embodiment of the present disclosure, the handover manager unit [307]
is further configured to detect, a failure of the handover of the UE [303] between the source
base station [304s] and the target base station [304t], via the first interface [305f] and the second
interface [305s]. It is to be noted that the failure of the handover of the UE [303] may include
25 but not limited to network congestion, interference, inaccurate configuration parameters, or the
user equipment issues. In an embodiment, it may include the first interface (preferably Xn
interface) being available, but the connection for performing the handover between the source
base station [304s] and the target base station [304t] is still not correctly established. The
handover manager unit [307] is further configured to blacklist, the target base station [304t] for
30 a pre-defined time period based on the detection of the failure of the handover of the UE [303]
between the source base station [304s] and the target base station [304t], via the first interface
[305f] and the second interface [305s].
16
[0059] In one such exemplary embodiment, the handover manager unit [307] may associate
the target base station [304t] with a first timer, where, when the first timer expires, the target
base station [304t] which was blacklisted, may now be available for a handover process. In
such exemplary embodiment, at the first timer expiration, the handover manager unit [307]
5 may reset the first timer.
[0060] In another exemplary embodiment, the first timer may have a timer value of two (2)
minutes, although the first timer value is purely implementation dependent (other
implementations may have different time values, and/or dynamically assign timer values based
10 on certain prevailing UE [303] and/or network conditions, applications in use, etc.)
[0061] In another exemplary embodiment, the first timer may be a configurable timer, which
can be configured by a service provider.
15 [0062] Therefore, based on the blacklisting of the target base station [304t], the handover
manager unit [307] is further configured to stop, the handover of the UE [303] and one or more
other UEs [303] to the target base station [304t] for the pre-defined time period.
[0063] In an exemplary embodiment of the present disclosure, the handover manager unit [307]
20 is configured to perform the handover of the UE [303] between the source base station [304s]
and the target base station [304t] via the second interface [305s], based on the detection of the
failure of the handover of the UE [303] between the source base station [304s] and the target
base station [304t] via the first interface [305f] for more than a predefined number of times.
25 [0064] In one such exemplary embodiment, the handover manager unit [307] may associate a
second timer with each failed attempt of handover to the target base station [304t] via the first
interface [305f]. When the second timer reaches a pre-defined threshold for the number of
failed attempts of handover of the UE to the target base station [304t], the handover manager
unit [307] performs the handover of the UE [303] between the source base station [304s] and
30 the target base station [304t] via the second interface [305s]. In such exemplary embodiment,
at the second timer expiration, the handover manager unit [307] may reset the second timer.
[0065] In another exemplary embodiment, the second timer may have a pre-defined threshold
of four (4) failed attempts, although the threshold value is purely implementation dependent
17
(other implementations may have different threshold values, and/or dynamically assign timer
values based on certain prevailing UE [303] and/or network conditions, applications in use,
etc.)
5 [0066] In an exemplary embodiment of the present disclosure, the system [300] is configured
to perform successful handover via Access and Mobility Management Function (AMF)
through another interface Ng, when there is any issue observed with Xn interface between
gNBs i.e., the source base station [304s] and the target base station [304t].
10 [0067] In an exemplary embodiment of the present disclosure, during the handover when Xn
interface is established from the source base station [304s] but down from the target base station
[304t], causing failure in handover, then the system [300] allows the UE [303] to perform
handover via the Ng interface when there is any informalities in Xn interface connection.
15 [0068] In an exemplary embodiment of the present disclosure, the system [300] allows the UE
[303] to do handover via the Ng interface when the first handover via the Xn interface fails due
to any cause like cell not available.
[0069] In an exemplary embodiment of the present disclosure, if the handover failure persists
20 on both the Ng and Xn interfaces, then the system [300] automatically blacklists the target base
station for certain duration and does not allow any handover attempts on the impacted target
base station.
[0070] It is pertinent to note that the system [300] is capable of implementing the features that
25 are obvious to a person skilled in the art in light of the disclosure as disclosed above and the
implementation of the system [300] is not limited to the above disclosure.
[0071] Referring to FIG. 4, an exemplary method flow diagram [400] for performing handover
in a wireless communication network, in accordance with exemplary implementations of the
30 present disclosure is shown. In an implementation the method [400] is performed by the system
[300]. Further, in an implementation, the system [300] may be present in a server device to
implement the features of the present disclosure. Also, as shown in FIG. 4, the method [400]
starts at step [402].
18
[0072] At step [404], the method [400] comprises identifying, by an identification unit [302],
a first interface [305f] between a source base station [304s] and a target base station [304t]. In
an exemplary aspect of the present disclosure, in the method, the source base station [304s] is
a source next-generation Node Base station (source gNB) from which the handover of the UE
5 [303] is to be done and the target base station [304t] is a target next-generation Node Base
station (target gNB) to which the handover of a user equipment (UE) [303] is to be done.
[0073] At step [406], the method [400] comprises transmitting, by a transceiver unit [306], a
handover request for the UE [303] from the source base station [304s] to the target base station
10 [304t] based on a measurement report received at the source base station [304s] from the UE
[303].
[0074] At step [408], the method [400] comprises receiving, via the transceiver unit [306] at
the source base station [304s], a handover response from the target base station [304t] based
15 on the handover request for the UE [303].
[0075] At step [410], the method [400] comprises detecting, by a handover manager unit [307],
a failure of the handover of the UE [303] between the source base station [304s] and the target
base station [304t], via the first interface [305f] based on the handover response. It is to be
20 noted that the failure of the handover of the UE [303] may include but not limited to network
congestion, interference, inaccurate configuration parameters, or the user equipment issues. In
an embodiment, it may include the first interface (preferably Xn interface) being available, but
the connection for performing the handover between the source base station [304s] and the
target base station [304t] is still not correctly established.
25
[0076] At step [412], the method [400] comprises performing, by the handover manager unit
[307], the handover of the UE [303] between the source base station [304s] and the target base
station [304t] via a second interface [305s] based at least on the detection of the failure of the
handover of the UE [303] between the source base station [304s] and the target base station
30 [304t] via the first interface [305f].
[0077] In an exemplary aspect of the present disclosure, the method [400] also comprises
detecting, by the handover manager unit [307], the failure of the handover of the UE [303]
between the source base station [304s] and the target base station [304t] via the first interface
19
[305f] and the second interface [305s]. The method [400] also comprises blacklisting, by the
handover manager unit [307], the target base station [304t] for a pre-defined time period based
on the detection of the failure of the handover of the UE [303] between the source base station
[304s] and the target base station [304t] via the first interface [305f] and the second interface
5 [305s].
[0078] In one such exemplary embodiment, the handover manager unit [307] may associate
the target base station [304t] with a first timer, where, when the first timer expires, the target
base station [304t] which was blacklisted, may now be available for a handover process. In
10 such exemplary embodiment, at the first timer expiration, the handover manager unit [307]
may reset the first timer.
[0079] In another exemplary embodiment, the first timer may have a timer value of two (2)
minutes, although the first timer value is purely implementation dependent (other
15 implementations may have different time values, and/or dynamically assign timer values based
on certain prevailing UE [303] and/or network conditions, applications in use, etc.
[0080] In another exemplary embodiment, the first timer may be a configurable timer, which
can be configured by a service provider.
20
[0081] And, the method [400] also comprises stopping, by the handover manager unit [307],
the handover of the UE [303] and one or more other UEs [303] to the target base station [304t]
for the pre-defined time period based on the blacklisting.
25 [0082] In an exemplary aspect of the present disclosure, in the method [400], the performing,
by the handover manager unit [307], the handover of the UE [303] between the source base
station [304s] and the target base station [304t] via the second interface [305s], is further based
on the detection of the failure of the handover of the UE [303] between the source base station
[304s] and the target base station [304t] via the first interface [305f] for more than a predefined
30 number of times.
[0083] In one such exemplary embodiment, the handover manager unit [307] may associate a
second timer with each failed attempt of handover to the target base station [304t] via the first
interface [305f]. When the second timer reaches a pre-defined threshold for the number of
20
failed attempts of handover of the UE to the target base station [304t], the handover manager
unit [307] performs the handover of the UE [303] between the source base station [304s] and
the target base station [304t] via the second interface [305s]. In such exemplary embodiment,
at the second timer expiration, the handover manager unit [307] may reset the second timer.
5
[0084] In another exemplary embodiment, the second timer may have a pre-defined threshold
of four (4) failed attempts, although the threshold value is purely implementation dependent
(other implementations may have different threshold values, and/or dynamically assign timer
values based on certain prevailing UE [303] and/or network conditions, applications in use,
10 etc.
[0085] In an exemplary aspect of the present disclosure, in the method, the first interface [305f]
is an Xn interface, and the second interface [305s] is a Ng interface.
15 [0086] Thereafter, the method [400] terminates at step [414].
[0087] Referring to FIG. 5, an exemplary flow diagram [500], for performing intelligent
handover for enhancing the user experience during mobility, in accordance with exemplary
embodiments of the present disclosure is shown.
20
[0088] As shown in flow diagram [500], at step [502], a Radio Resource Control (RRC)
connection is established between a user equipment (UE) and the SgNB (i.e., the source gNB/
source base station from where handover is to occur).
25 [0089] At step [504], the Xn interface is established between the SgNB and the TgNB (i.e., the
target gNB/ target base station).
[0090] At steps [506] and [508], the UE prepares the measurement report, and the handover
request is sent from SgNB to TgNB. Thereafter, at step [510], the SgNB receives the handover
30 response from the TgNB.
[0091] At step [512] the Xn interface is used for establishing the connection for handover from
the one end of the SgNB to the TgNB. But the Xn interface being down from another end i.e.,
21
the TgNB, the present disclosure performs the intelligent handover via an AMF with the help
of the Ng/N2 interface. The SgNB then uses the Ng/N2 interface via the AMF.
[0092] At step [514], the AMF establishes the connection with the TgNB with the help of
5 another Ng/N2 interface i.e., the interface between the AMF and the TgNB.
[0093] At step [516], the TgNB establishes the connection with the AMF which confirms the
passage for handover to the SgNB.
10 [0094] At step [518], the SgNB receives alternative path for performing handover to the TgNB
with the help of the AMF via the Ng/N2 interface and therefore attempts to perform handover.
[0095] At step [520], the handover from the SgNB to the TgNB takes place.
15 [0096] The present disclosure also encompasses, automatically blacklisting the target base
station for a certain duration and not allow any hand over attempts on impacted target base
station if the hand over failure persists for a pre-defined number of times on its interface during
processing of handover request.
20 [0097] This way, the present disclosure performs intelligent handover process to evaluate the
failure and the cause of failure and makes intelligent decision to perform successful handover.
[0098] Referring to FIG. 6, an exemplary method flow diagram [600], for blacklisting a target
base station when the handover fails on both the interfaces, in accordance with exemplary
25 embodiments of the present disclosure is shown. In an implementation, the method [600] is
performed by the system [300]. As shown in Fig. 6, the method [600] starts at step [602].
[0099] At step [604], the method [600] as disclosed by the present disclosure comprises
detecting a failure of the handover of the UE between the source base station and the target
30 base station via both the Xn and the Ng interfaces.
[0100] Next, at step [606], the method [600] as disclosed by the present disclosure, comprises
blacklisting the target base station for a pre-defined duration and not allow any handover
attempts to the impacted target base station for the pre-defined duration. The duration for which
22
the target base station is blacklisted is configurable and may be set by the administrator user of
the system [300].
[0101] Thereafter, the method terminates at step [608].
5
[0102] The present disclosure further discloses a non-transitory computer readable storage
medium storing instructions for performing handover in a wireless communication network,
the instructions include executable code which, when executed by a one or more units of a
system, causes: an identification unit [302] to identify, a Radio Resource Control (RRC)
10 connection between a user equipment (UE) [303] and a source base station [304s] and to
identify, a first interface [305f] between the source base station [304s] and a target base station
[304t]; a transceiver unit [306] to transmit, a handover request for the UE [303] from the source
base station [304s] to the target base station [304t] based on a measurement report received at
the source base station [304s] from the UE [303], and to receive, at the source base station
15 [304s], a handover response from the target base station [304t] based on the handover request
for the UE [303]; a handover manager unit [307] configured to detect a failure of the handover
of the UE [303] between the source base station [304s] and the target base station [304t], via
the first interface [305f] based on the handover response, and to perform the handover of the
UE [303] between the source base station [304s] and the target base station [304t] via a second
20 interface [305s] based at least on the detection of failure of the handover of the UE [303]
between the source base station [304s] and the target base station [304t] via the first interface
[305f].
[0103] The present disclosure further discloses a User Equipment (UE) [303] in a wireless
25 communication network. The UE [303] comprises a transceiver unit [306] which is configured
to send a request to the system [300] for performing the handover from a source base station
[304s] to a target base station [304t]. The transceiver unit [306] is further configured to transmit
a measurement report to the source base station [304s]. The UE [303] is then handed off to the
target base station [304t] based on a handover response received from the system [300]. It is to
30 be noted that the handoff between the source base station [304s] and the target base station
[304t] happens via at least one of an Xn interface and a Ng interface.
[0104] As is evident from the above, the present disclosure provides a technically advanced
solution for performing handover in a wireless communication network. The present solution
23
thus enhances user experience during mobility. The present disclosure performs reliable
handover procedure when Xn interface is down at any end on either side of gNB. Furthermore,
the present disclosure performs quick handover whenever required after triggering the
measurement configuration for enhancing the user experience by handling the mobility
5 scenario efficiently. This helps the UE [303] to perform quick handover in the scenario where
handover is getting stuck or fails due to some uncertain reasons.
[0105] While considerable emphasis has been placed herein on the disclosed implementations,
it will be appreciated that many implementations can be made and that many changes can be
10 made to the implementations without departing from the principles of the present disclosure.
These and other changes in the implementations of the present disclosure will be apparent to
those skilled in the art, whereby it is to be understood that the foregoing descriptive matter to
be implemented is illustrative and non-limiting.
15 [0106] Further, in accordance with the present disclosure, it is to be acknowledged that the
functionality described for the various components/units can be implemented interchangeably.
While specific embodiments may disclose a particular functionality of these units for clarity, it
is recognized that various configurations and combinations thereof are within the scope of the
disclosure. The functionality of specific units as disclosed in the disclosure should not be
20 construed as limiting the scope of the present disclosure. Consequently, alternative
arrangements and substitutions of units, provided they achieve the intended functionality
described herein, are considered to be encompassed within the scope of the present disclosure.
24
We Claim:
1. A method [400] for performing handover in a wireless communication
network, the method [400] comprising:
5 - identifying, by an identification unit [302], a first interface [305f]
between a source base station [304s] and a target base station [304t];
- transmitting, by a transceiver unit [306], a handover request for a user
equipment (UE) [303] from the source base station [304s] to the target
base station [304t] based on a measurement report received at the source
10 base station [304s] from the UE [303];
- receiving, via the transceiver unit [306] at the source base station [304s],
a handover response from the target base station [304t] based on the
handover request for the UE [303];
- detecting, by a handover manager unit [307], a failure of the handover
15 of the UE [303] between the source base station [304s] and the target
base station [304t], via the first interface [305f] based on the handover
response; and
- performing, by the handover manager unit [307], the handover of the
UE [303] between the source base station [304s] and the target base
20 station [304t] via a second interface [305s] based at least on the
detection of failure of the handover of the UE [303] between the source
base station [304s] and the target base station [304t] via the first
interface [305f].
2. The method [400] as claimed in claim 1, wherein the source base station
25 [304s] is a source next-generation Node Base station (source gNB) from
which the handover of the UE [303] is to be done and the target base station
[304t] is a target next-generation Node Base station (target gNB) to which
the handover of the UE [303] is to be done.
3. The method [400] as claimed in claim 1, wherein at least one of: the first
30 interface [305f] is an Xn interface, and the second interface [305s] is a Ng
interface.
25
4. The method [400] as claimed in claim 1, the method [400] further
comprises:
- detecting, by the handover manager unit [307], a failure of the handover
of the UE [303] between the source base station [304s] and the target
5 base station [304t] via the first interface [305f] and the second interface
[305s],
- blacklisting, by the handover manager unit [307], the target base station
[304t] for a pre-defined time period based on the detection of the failure
of the handover of the UE [303] between the source base station [304s]
10 and the target base station [304t] via the first interface [305f] and the
second interface [305s], and
- stopping, by the handover manager unit [307], the handover of the UE
[303] and one or more other UEs [303] to the target base station [304t]
for the pre-defined time period based on the blacklisting.
15 5. The method [400] as claimed in claim 1 wherein the performing, by the
handover manager unit [307], the handover of the UE [303] between the
source base station [304s] and the target base station [304t] via the second
interface [305s], is further based on the detection of the failure of the
handover of the UE [303] between the source base station [304s] and the
20 target base station [304t] via the first interface [305f] for more than a
predefined number of times.
6. A system [300] for performing handover in a wireless communication
network, the system [300] comprising:
- an identification unit [302], configured to:
25 o identify, a first interface [305f] between a source base station
[304s] and a target base station [304t];
- a transceiver unit [306] connected at least to the identification unit [302],
the transceiver unit [306] configured to:
o transmit, a handover request for a user equipment (UE) [303]
30 from the source base station [304s] to the target base station
26
[304t] based on a measurement report received at the source base
station [304s] from the UE [303], and
o receive, at the source base station [304s], a handover response
from the target base station [304t] based on the handover request
5 for the UE [303]; and
- a handover manager unit [307] connected at least to the transceiver unit
[306] and the identification unit [302], the handover manager unit [307]
configured to:
o detect a failure of the handover of the UE [303] between the
10 source base station [304s] and the target base station [304t], via
the first interface [305f] based on the handover response, and
o perform the handover of the UE [303] between the source base
station [304s] and the target base station [304t] via a second
interface [305s] based at least on the detection of failure of the
15 handover of the UE [303] between the source base station [304s]
and the target base station [304t] via the first interface [305f].
7. The system [300] as claimed in claim 6, wherein the source base station
[304s] is a source next-generation Node B (source gNB) from which the
handover of the UE [303] is to be done and the target base station [304t] is
20 a target next-generation Node B (target gNB) to which the handover of the
UE [303] is to be done.
8. The system [300] as claimed in claim 6, wherein the first interface [305f] is
an Xn interface, and the second interface [305s] is a Ng interface.
9. The system [300] as claimed in claim 6, wherein the handover manager unit
25 [307] is further configured to:
- detect, a failure of the handover of the UE [303] between the source base
station [304s] and the target base station [304t], via the first interface
[305f] and the second interface [305s],
- blacklist, the target base station [304t] for a pre-defined time period
30 based on the detection of the failure of the handover of the UE [303]
27
between the source base station [304s] and the target base station [304t],
via the first interface [305f] and the second interface [305s], and
- stop, the handover of the UE [303] and one or more other UEs [303] to
the target base station [304t] for the pre-defined time period based on
5 the blacklisting.
10. The system [300] as claimed in claim 6 wherein the handover manager unit
[307] is configured to perform the handover of the UE [303] between the
source base station [304s] and the target base station [304t] via the second
interface [305s], is further based on the detection of the failure of the
10 handover of the UE [303] between the source base station [304s] and the
target base station [304t] via the first interface [305f] for more than a
predefined number of times.
11. A User Equipment (UE) [303] in a wireless communication network, the
UE [303] comprising:
15 a transceiver unit [306], wherein the transceiver unit [306] is configured to:
o send a request to a system [300] for performing handover from
a source base station [304s] to a target base station [304t], and
o transmit a measurement report to the source base station [304s],
wherein the UE [303] is handed off to the target base station [304t] based on a
20 handover response received from the system [300], wherein the handoff between
the source base station [304s] and the target base station [304t] happens via at least
one of an Xn interface and a Ng interface.