WO2021249068A1

WO2021249068A1 - Method and system for detecting a target cell with 5g cell support in 5g nsa mode

Info

Publication number: WO2021249068A1
Application number: PCT/CN2021/092054
Authority: WO
Inventors: Ashish Mathur; Naveen Bodapati; Manish Kumar; Mohd Parvez AHMAD
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2020-06-11
Filing date: 2021-05-07
Publication date: 2021-12-16
Anticipated expiration: 2022-12-11

Abstract

The disclosure provides methods and system for detecting a target cell with 5G cell support in a 5G NSA Mode. The method encompasses identifying, at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored list and a supported full frequency band. The method further stores, the at least one intra frequency cell in a first stack. Thereafter the method detects, a target cell with 5G cell support, from the at least one inter frequency cell, on the basis of a 5G cell selection criteria. Further, the method determines, one of a positive response and a negative response based on the target cell, from the at least one inter frequency cell. Thereafter the method detects, the target cell, from the first stack, based on the 5G cell selection criteria and the negative response.

Description

METHOD AND SYSTEM FOR DETECTING A TARGET CELL WITH 5G CELL SUPPORT IN 5G NSA MODE

FIELD OF DISCLOSURE

The present disclosure generally relates to the field of cellular network system and more particularly to a system and method of detecting a target cell with 5G cell support in a 5G NSA Mode.

BACKGROUND OF THE DISCLOSURE

The following description of 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 be appreciated that this section be used only to enhance the understanding of the reader with respect to the present disclosure, and not as admissions of prior art.

From the past few years the field of cellular communication network has been evolving at a rapid rate. The implementation of advanced techniques and technologies in the cellular communication network systems has provided the users a number of fast, reliable and advanced ways of communications. For instance, 5 ^th generation non-standalone mode (5G NSA Mode) provides the users a solution to avail 5G services in a 5G network, wherein the 5G network is supported by the existing 4 ^th generation (4G) network infrastructure to provide the 5G services. Further, a number of wireless communication system standards and protocols are provided under 3rd Generation Partnership Project (3GPP) specifications relating to the working of the user equipment (UE) in the 5G NSA Mode.

Typically, in order to avail 5G services via the user equipment (UE) in the 5G NSA Mode, the UE shall first register on a 4G cell, wherein the 4G cell is further having a 5G cell support in the 5G NSA Mode. Thereafter, the 4G cell then sends the 5G cell configurations to the UE and the UE thereafter needs to read the configuration of the 5G cell in order to register on the 5G cell to avail the 5G services.

Along with the implementation of various techniques and technologies to provide 5G services in the 5G NSA mode, there also arise some challenges. For instance, sometimes the user equipment (UE) is not able to use the services provided by its corresponding cellular network operator as the UE fails to register with the received 5G Cell due to configuration issues. The user equipment (UE) in such cases declares the radio link failure on the EUTRAN Cell and further needs to perform RRC Connection Re-establishment in order to obtain Network access.

Further, as per the current existing solutions during RRC Connection Re-establishment in 5G NSA mode the UE will consider the standard 3GPP Cell Selection Criteria for choosing the Target Cell for RRC Connection Re-establishment, wherein the Cell Selection Criteria is based on the selection of the strongest available cell and is irrespective of the availability of the 5G cell support in the strongest available cell. Therefore, if based on the existing cell selection criteria, such a cell is selected that does not provide 5G cell support then in such scenarios the user equipment (UE) fails to avail the 5G services in the 5G NSA mode.

In view of these and other existing limitations, there arises an imperative need to provide a solution to overcome the limitations of prior existing solutions and to provide a more efficient method and system for detecting a target cell with 5G cell support in the 5G NSA Mode.

SUMMARY

This section is provided to introduce certain objects and 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.

In order to overcome at least a few problems associated with the known solutions as provided in the previous section, an object of the present disclosure is to provide a novel method and system for detecting a target cell with 5G cell support in a 5G NSA Mode to optimize the 5G user experience in the NSA configuration. It is another object of the disclosure to allow the user to seamlessly use the 5G Services in NSA mode. Also, the object of the present disclosure is to provide a solution to find any other available 5G cell in an instance the user equipment is not able to comply with current 5G cell configuration in the NSA mode. Yet another object of the present disclosure is to optimize the handling of the target cell selection such that UE functions as per 3GPP specifications and also ensuring that the UE is able to use 5G Services seamlessly.

In order to achieve the afore-mentioned objectives, the present disclosure provides a method and system/user equipment for detecting a target cell with 5G cell support in a 5G NSA Mode.

One aspect of the present disclosure relates to a method for detecting a target cell with 5G cell support in a 5G NSA Mode. The method comprising identifying, via a user equipment, at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored list and a supported full frequency band. Thereafter, the method leads to storing, via the user equipment, the at least one intra frequency cell in a first stack. The method then encompasses detecting, via the user equipment, a target cell with 5G cell support in 5G NSA Mode, from the at least one inter-frequency cell. Further, the method comprises determining, via the user equipment, one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter-frequency cell. Thereafter the method encompasses detecting, via the user equipment, the target cell with 5G cell support in 5G NSA Mode, from the first stack, and based on a 5G cell selection criteria and the negative response.

Another aspect of the present disclosure relates to a user equipment/system for detecting a target cell with 5G cell support in 5G NSA Mode. The user equipment comprises a processing unit, configured to identify, at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored information list and a supported full frequency band. The user equipment further comprises a storage unit, configured to store, the at least one intra frequency cell in a first stack. Thereafter the user equipment comprises a detection unit, configured to detect a target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. Further the processing unit, further configured to determine one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. Thereafter the detection unit, further configured to detect the target cell with 5G cell support in 5G NSA Mode, from the first stack, and based on a 5G cell selection criteria and the negative response.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein, and constitute a part of this disclosure, illustrate exemplary embodiments of the disclosed methods and systems in 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. Some drawings may indicate the components using block diagrams and may not represent the internal circuitry of each component. It will be appreciated by those skilled in the art that disclosure of such drawings includes disclosure of electrical components, electronic components or circuitry commonly used to implement such components.

FIG. 1 illustrates a block diagram of an exemplary user equipment [100] for detecting a target cell with 5G cell support in 5G NSA Mode, in accordance with exemplary embodiment of the present disclosure.

FIG. 2 illustrates an exemplary method [200] for detecting a target cell with 5G cell support in 5G NSA Mode, in accordance with exemplary embodiment of the present disclosure.

The foregoing shall be more apparent from the following more detailed description of the disclosure.

DETAILED DESCRIPTION

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 can each be used 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.

The present disclosure provides the users, a solution relating to optimizing 5G user experience in NSA configuration. The present disclosure encompasses detecting a target cell with 5G cell support in a 5G NSA Mode. In 5G NSA Mode, after receiving the required 5G Cell Configuration i.e. RRCConnectionReconfiguration Message comprising mobilityControlInfo and details of 5G cell, a user equipment is required to perform synchronization to gain services on 5G cell. However sometimes the user equipment fails to comply with the 5G Cell configuration and is unable to register on the 5G cell. Thus, the user equipment in the scenario, declares radio link failure on the EUTRAN Cell on which the user equipment was camped and thereafter the user equipment needs to perform RRC Connection Re-establishment in order to obtain network access. Also, during the RRC Connection Re-establishment the user equipment considers only the standard 3GPP cell selection criteria for choosing the target cell for RRC Connection Re-establishment, wherein the cell selection criteria comprises identification of the strongest available cell and is irrespective of the availability of the 5G cell support in the strongest available cell.

More specifically, the existing cell selection procedure includes two mechanism. The first mechanism is applied when a new UE attempts to establish re-establishment, for instance if the UE is powered on. In this case the UE scans all RF channels and thereafter selects the strongest cell. The second mechanism is applied when the UE has been previously camped on to other cells. As per the second mechanism, the UE selects a cell based on the previously stored list of cells i.e. those cells onto which UE has been previously camped. The present disclosure, in such scenarios, provides a solution to optimize the handling of the target cell selection in 5G NSA Mode, such that the user equipment functions as per the 3GPP specifications and also ensuring that the user equipment is able to use 5G Services seamlessly. More specifically, the present disclosure provides a modified cell selection criteria that achieves the detection of the target cell with 5G cell support in the 5G NSA Mode.

As used herein, a “user equipment” , “electronic device” , “user device” , and/or “smart device” may be any electrical, electronic, electromechanical and/or computing device or equipment, which is capable of operating on cellular communication network to avail various services such as voice and/or data. The electronic 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 and is obvious to a person skilled in the art.

As used herein, a “processing unit” or “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 microprocessors in association with a 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 processing unit is a hardware processor.

As used herein, a “storage unit” refers to a machine or computer-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.

As used herein, a “detection unit” may be an intelligent unit having an analysing, computing and detecting capability, and/or any other such similar unit configured to implement the features of the present disclosure and is obvious to a person skilled in the art.

As used herein, “couple” and its cognate terms, such as “couples” and “coupled” includes a physical connection (such as a conductor) , a virtual connection (such as through randomly assigned memory locations of data memory device) , a logical connection (such as through logical gates of semiconducting device) , other suitable connections, or a combination of such connections, as may be obvious to a skilled person.

The disclosure is further explained in detail below with reference now to the diagrams.

FIG. 1 illustrates an exemplary block diagram of a user equipment [100] for detecting a target cell with 5G cell support in 5G NSA Mode, in accordance with the exemplary embodiments of the present disclosure.

The user equipment [100] comprises at least one processing unit [102] , at least one storage unit [104] and at least one detection unit [106] , wherein all the components are assumed to be connected to each other unless otherwise indicated below. Also, in Fig. 1 only few units are shown, however the user equipment [100] may comprise multiple such units or the user equipment may comprise any such numbers of the units, obvious to a person skilled in the art or as required to implement the features of the present disclosure.

The user equipment [100] additionally may comprise of one or more other components such as antenna, analog processing units, analog to digital converters, digital processing units, digital to analog converters, storage, graphics processing units, display modules, etc.

The at least one processing unit [102] of the user equipment [100] is configured to identify, at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored information list and a supported full frequency band. The processing unit [102] firstly configured to determine the presence of the pre-stored list in the user equipment [100] . The processing unit [102] is further configured to identify the at least one intra frequency cell and at least one inter frequency cell from the pre-stored list. The processing unit [102] is then configured to identify the at least one intra frequency cell and at least one inter frequency cell from the supported full frequency band associated with the user equipment [100] in an event the pre-stored list is not present in the user equipment [100] . Further, the pre-stored list comprises details of at least one last camped cell of the user equipment [100] . The intra frequency cell is the cell having same frequency as that of a last camped cell of the user equipment [100] . Also, inter frequency cell is the cell having different frequency as compared to the operating frequency of the last camped cell of the user equipment [100] .

The at least one storage unit [104] is connected to the at least one processing unit [102] . The at least one storage unit [104] is configured to store, the at least one intra frequency cell in a first stack. The first stack encompasses one or more identified at least one intra frequency cell in an arranged order. The storing of the at least one intra frequency cell in the first stack is to avoid the problem of reconfiguration failure due to frequency band combination in the NSA Mode, as the intra frequency cell is operating on the same frequency as that of the last camped cell and have higher chances of reconfiguration failure as compared to the inter frequency cell. Also, the storage unit [104] is also configured to store, in a second stack, at least one cell information of the last camped EUTRAN cell on which the Radio Link failure was observed, along with a received RRCConnectionReconfiguration Message comprising mobilityControlInfo and the details of the 5G cell. The cell information of the last camped EUTRAN cell includes but not limited to physical cell identity, operating frequency, etc.

The at least one detection unit [106] is connected to the at least one processing unit [102] and the at least one storage unit [104] . The at least one detection unit [106] is configured to detect a target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell, wherein the detecting is based on a 5G cell selection criteria. The 5G cell selection criteria further comprises a standard cell selection criteria to select a EUTRAN Cell in the 5G NSA mode and a 5G cell support in the selected EUTRAN Cell. Also, the standard cell selection criteria is the 3GPP cell selection criteria based on cell measurement. The detection unit [106] as per the standard cell selection criteria measures the cell strength of one of the at least one inter frequency cell and if the measured cell strength satisfies the standard 3GPP cell selection criteria, the detection unit [106] then leads to determining the 5G cell support in the inter frequency cell, otherwise the detection unit [106] then leads to another identified inter frequency cell to check the 5G cell selection criteria for the another identified inter frequency cell.

The at least one processing unit [102] is further configured to determine one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. The positive response comprises a successful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. Also, the negative response comprises an unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell.

Further, in an event of positive response, the processing unit [102] is further configured to initiate a RRC Connection Re-establishment procedure with the detected target cell with 5G cell support in 5G NSA Mode, from the at least one identified inter frequency cell.

In an event of negative response, the detection unit [106] , is further configured to detect the target cell with 5G cell support in 5G NSA Mode, from the first stack comprising at least one identified intra frequency cell, wherein the detection is based on the 5G cell selection criteria and the negative response. In order to detect the target cell from the first stack, the detection unit [106] as per the standard cell selection criteria measures the cell strength of one of the at least one intra frequency cell stored in the first stack and if the measured cell strength satisfies the standard 3GPP cell selection criteria, the detection unit [106] then leads to determining the 5G cell support in the intra frequency cell, otherwise the detection unit [106] then leads to another identified intra frequency cell in the first stack to check the 5G cell selection criteria for the another identified intra frequency cell.

Thereafter, if the target cell with 5G cell support in 5G NSA Mode is identified from the at least one identified intra frequency cell, the processing unit [102] is further configured to initiate the RRC Connection Re-establishment procedure with the detected target cell with 5G cell support in 5G NSA Mode, from the at least one identified intra frequency cell.

Also, in an event of unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell and the first stack comprising at least one intra frequency cell, the processing unit [102] is further configured to initiate the RRC Connection Re-establishment procedure with the last camped EUTRAN cell stored in the second stack based on the 3GPP specifications.

Referring to Fig. 2, an exemplary method flow diagram [200] , depicting method of detecting a target cell with 5G cell support in a 5G NSA Mode, in accordance with exemplary embodiment of the present disclosure is shown. As shown in Fig. 2, the method begins at step [202] . The disclosure encompasses that the method begins when a user equipment [100] receives a RRC Connection Reconfigure message from the network wherein the reconfiguration message comprises a 5G cell configuration with NSA mode; and the user equipment [100] is unable to perform synchronization on the target 5G cell and declares radio link failure. In such a situation, the user equipment [100] requires to camp onto another cell having 5G configuration with NSA mode.

At step [204] , the method comprises identifying, via a user equipment [100] , at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored list and a supported full frequency band. To identify the inter frequency cell and the intra frequency cell the method firstly encompasses determining the presence of the pre-stored list in the user equipment [100] and if the pre-stored list is present, the method then the intra frequency cell and at least one inter frequency cell are identified from the pre-stored list. In an event the pre- stored list is not present in the user equipment [100] , then the intra frequency cell and the inter frequency cell are identified from the the supported full frequency band associated with the user equipment [100] , i.e. the user equipment [100] performs a full-band scan to identify the required cell.

Further, the pre-stored list comprises details of at least one last camped cell of the user equipment [100] , i.e. list of all cells onto which the user equipment [100] have been previously camped/latched. The intra frequency cell is the cell having same frequency as that of a last camped cell of the user equipment [100] . Also, inter frequency cell is the cell having different frequency as compared to the operating frequency of the last camped cell of the user equipment [100] .

For instance, the user equipment [100] may have experienced radio link failure with a cell X operating in the 1800 MHz frequency. In an example, the user equipment [100] may store the following pre-stored list, wherein the user equipment [100] has been previously camped onto Cell_A, Cell_B and Cell_C.

In this example, Cell_Ais an intra-frequency cell with respect to Cell_X. Also, Cell_B and Cell_C are inter-frequency cells with respect to Cell_X. The disclosure in step [104] identifies these inter-frequency cells and inter-frequency cells from the pre-stored list.

Next, at step [206] , the method encompasses, storing, via the user equipment [100] , the at least one intra frequency cell in a first stack. The first stack encompasses one or more identified at least one intra frequency cell in an arranged order. The storing of the at least one intra frequency cell in the first stack is to avoid the problem of reconfiguration failure due to frequency band combination in the NSA Mode, as the intra frequency cell is operating on the same frequency as that of the last camped cell and have higher chances of reconfiguration failure as compared to the inter frequency cell. Also, the method further encompasses storing, in a second stack, at least one cell information of the last camped EUTRAN cell on which the Radio Link failure was observed, along with a received RRCConnectionReconfiguration Message comprising mobilityControlInfo and the details of the 5G cell. The cell information of the last camped EUTRAN cell includes but not limited to physical cell identity, operating frequency etc.

In the above example, Cell_Ais stored in the first stack in step [206] for processing at a later stage, if required.

Next, at step [208] , the method comprises, detecting, via the user equipment [100] , a target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell, wherein the detecting is based on a 5G cell selection criteria. The 5G cell selection criteria further comprises a standard cell selection criteria to select a EUTRAN Cell in the 5G NSA mode and a 5G cell support in the selected EUTRAN Cell. Also, the standard cell selection criteria is the 3GPP cell selection criteria based on cell measurement. The method further as per the standard cell selection criteria, comprises, measuring a cell strength associated with one of the at least one inter frequency cell and thereafter if the measured cell strength satisfies the standard 3GPP cell selection criteria, the method then leads to determining the 5G cell support in the inter frequency cell, otherwise the method leads to another identified inter frequency cell to check the 5G cell selection criteria for the another identified inter frequency cell. Thus, the disclosure utilizes a more advanced and better cell selection criteria where not only the cell measurements are taken into account, but the 5G cell configuration in NSA mode is also taken into account before selecting any target cell. This also overcomes the problem of the prior art where 5G support of a target cell is not taken into consideration while selecting a target cell in cases of radio link failure.

In the above example, the disclosure encompasses traversing the list of inter-frequency cells comprising Cell_B and Cell_C and applying the cell selection criteria thereon. Say for instance, the Cell_B satisfies the standard 3GPP criteria, however, does not provide 5G support in NSA mode. In such a case, the disclosure encompasses moving onto the next cell in the list, i.e. Cell_C to determine if it satisfies the cell selection criteria. If for instance, the Cell_C also satisfies the standard cell selection criteria and also supports 5G in NSA mode, in that case Cell_C is selected as the target cell.

Next, at step [210] , the method comprises, determining, via the user equipment [100] , one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. The positive response comprises a successful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. Also, the negative response comprises an unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell. Thus, if at step [208] , a target cell with 5G cell support in 5G NSA Mode is detected in the list of inter frequency cells, then a positive response is generated, else a negative response is generated.

In the above example, a positive response is generated since the target cell Cell_C is found in the list of inter-frequency cells. In another example, if Cell_C does not meet the selection criteria, then a negative response may be generated.

Further in an event of positive response the method further encompasses initiating a RRC Connection Re-establishment procedure with the detected, target cell with 5G cell support in 5G NSA Mode, from the at least one identified inter frequency cell.

Thereafter, at step [212] , the method comprises, detecting, via the user equipment [100] , the target cell with 5G cell support in 5G NSA Mode, from the first stack, and based on the 5G cell selection criteria and the negative response. For, instance in an event of negative response the method comprises detecting the target cell with 5G cell support in 5G NSA Mode, from the stored at least one intra frequency cell in the first stack, wherein the detection is based on the 5G cell selection criteria. Furthermore, in order to detect the target cell from the first stack, the method as per the standard cell selection criteria measures the cell strength of one of the at least one intra frequency cell stored in the first stack and if the measured cell strength satisfies the standard 3GPP cell selection criteria, the method then leads to determining the 5G cell support in the intra frequency cell, otherwise the method then leads to another identified intra frequency cell in the first stack to check the 5G cell selection criteria for the another identified intra frequency cell.

Thereafter, if the target cell with 5G cell support in 5G NSA Mode is identified from the at least one identified intra frequency cell, the method further initiates the RRC Connection Re-establishment procedure with the detected, target cell with 5G cell support in 5G NSA Mode, from the at least one identified intra frequency cell.

After successfully detecting the target cell with 5G cell support in the 5G NSA Mode, the method further terminates at step [214] .

The disclosure encompasses that the method first detects the target cell with 5G cell support from the pre-stored list. If no target cell with 5G cell support is detected from the pre-stored list, the method will lead to the detection of the target cell with 5G cell support from the supported full frequency band of the user equipment [100] .

In an event of unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell and as well as from the first stack comprising at least one intra frequency cell, the method encompasses initiating the RRC Connection Re-establishment procedure with the last camped EUTRAN cell stored in the second stack based on the 3GPP specifications.

While considerable emphasis has been placed herein on the disclosed embodiments, it will be appreciated that many embodiments can be made and that many changes can be made to the embodiments without departing from the principles of the present disclosure. These and other changes in the embodiments 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.

Claims

A method [200] of detecting a target cell with 5G cell support in a 5G NSA Mode, the method [200] comprising:

- identifying, via a user equipment [100] , at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored list and a supported full frequency band;

- storing, via the user equipment [100] , the at least one intra frequency cell in a first stack;

- detecting, via the user equipment [100] , a target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell;

- determining, via the user equipment [100] , one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell; and

- detecting, via the user equipment [100] , the target cell with 5G cell support in 5G NSA Mode, from the first stack and based on a 5G cell selection criteria and the negative response.
The method as claimed in claim 1 wherein the 5G cell selection criteria comprises:

a standard cell selection criteria to select a EUTRAN Cell, and

a 5G cell support in the selected EUTRAN Cell.
The method as claimed in claim 1 wherein the positive response comprising a successful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell.
The method as claimed in claim 1 wherein the negative response comprising an unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell.
The method as claimed in claim 1 wherein the method further comprising initiating a RRC Connection Re-establishment procedure with the target cell with 5G cell support in 5G NSA Mode.
The method as claimed in claim 1 wherein the method further comprising storing, at the user equipment [100] , at least one cell information of a last camped EUTRAN Cell in a second stack.
The method as claimed in claim 6 wherein the method further comprising initiating the RRC Connection Re-establishment procedure with the last camped EUTRAN Cell stored in the second stack.
The method as claimed in claim 7 wherein the initiating of the RRC Connection Re-establishment procedure with the last camped EUTRAN Cell is based on an event of unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell and the first stack.
A user equipment [100] for detecting a target cell with 5G cell support in 5G NSA Mode, the user equipment [100] comprising:

- a processing unit [102] , configured to identify, at least one intra frequency cell and at least one inter frequency cell from at least one of a pre-stored information list and a supported full frequency band;

- a storage unit [104] , configured to store, the at least one intra frequency cell in a first stack;

- a detection unit [106] , configured to detect a target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell;

wherein:

the processing unit [102] , further configured to determine one of a positive response and a negative response based on the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell, and

the detection unit [106] , further configured to detect the target cell with 5G cell support in 5G NSA Mode, from the first stack, and based on a 5G cell selection criteria and the negative response.
The user equipment [100] as claimed in claim 9 wherein the 5G cell selection criteria comprises:

a standard cell selection criteria to select EUTRAN Cell, and

a 5G cell support in the selected EUTRAN Cell.
The user equipment [100] as claimed in claim 9 wherein the positive response comprises a successful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell.
The user equipment [100] as claimed in claim 9 wherein the negative response comprises an unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell.
The user equipment [100] as claimed in claim 9 wherein the processing unit [102] is further configured to initiate a RRC Connection Re-establishment procedure with the target cell with 5G cell support in 5G NSA Mode.
The user equipment [100] as claimed in claim 9 wherein the storage unit [104] is further configured to store, at least one cell information of a last camped EUTRAN cell in a second stack.
The user equipment [100] as claimed in claim 14 wherein the processing unit [102] is further configured to initiate the RRC Connection Re-establishment procedure with the last camped EUTRAN cell stored in the second stack.
The user equipment [100] as claimed in claim 15 wherein the initiation of the RRC Connection Re-establishment procedure with the last camped EUTRAN cell is based on an event of unsuccessful detection of the target cell with 5G cell support in 5G NSA Mode, from the at least one inter frequency cell and the first stack.