DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
The Examiner acknowledges the amendments to the specification and happily withdraws the corresponding objections these amendments corrected.
The Examiner also acknowledges the receipt of non-patent literature documents “R2-2205054” and “R2-2208617” which were listed on their own lines in the IDS filed on 09/15/2023 but whose names are actually parts of other documents that were included in the IDS and accordingly considered.
The amendment submitted on 01/30/2026 has been received and considered by the examiner. Claims 19, 21, 26, 28, and 31 were amended, and claims 33-34 were newly added. Claims 1-18 were previously cancelled. Also, Claim 25 is marked in the new listing of the claims as “Currently Amended”, but this appears to be a mistake because there is no difference between the versions of Claim 25 in the listings filed on 09/17/2025 and 01/30/2026.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Claim Rejections - 35 USC § 112
After considering the applicant’s arguments, the 112(b) rejections of claims 19-32 are withdrawn and interpreted in light of paragraph 0176 of the specification which defines an “acceptable cell” as one that supports emergency voice services.
Response to Arguments
On page 12 of their remarks, the Applicant attempts to distinguish between the claimed invention and Ramachandra, writing, “Ramachandra merely describes generating RLF information containing failure details and time-to-reconnect information when a HO failure occurs in an Inter-RAT situation, however, it does not disclose the feature that such an inter-RAT HO is a ‘fallback for emergency services’” (Applicant Remarks, p. 12).
On this point, the Examiner agrees with the Applicant. However, Ramachandra was not cited to teach the claim limitation requiring that “the handover is for the emergency service fallback”. Rather, Shih teaches this limitation and was cited on this point. In response to the Applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Later on page 12, the Applicant also writes that “unlike the present application – which searches for an ‘acceptable cell’ to support emergency services when a suitable cell is not found - Ramachandra is directed to an operation of returning to the source cell [emphasis in original]” (Remarks, p. 12).
However, the Examiner respectfully disagrees with this interpretation. Fig. 4 in Ramachandra, for example, depicts “the UE’s operations during an exemplary LTE RF procedure” and includes a step where “UE selects target cell for recovery” (Ramachandra, 0076, Fig. 4). Paragraph 0076 further clarifies that RRC reestablishment includes a UE “searching for the best target cell”.
Furthermore, Shih, not Ramachandra, was cited to teach the limitation requiring “selecting an acceptable cell of the second RAT supporting an emergency call”. Again, in response to Applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references.
With respect to Shih, on page 13 of their remarks, the Applicant writes that “Shih merely describes technology regarding emergency services for a terminal, i.e., selecting an acceptable cell that supports emergency services if the selected cell does not”, adding that “Shih relates to cell selection in a Standalone Non-Public Network environment and subsequently selecting an acceptable cell of another NPN. This is fundamentally different from the present application’s operation of ‘selecting an acceptable cell in a HOF situation during an inter-RAT HO’” (Remarks, p. 13).
Again, the Examiner largely agrees with the Applicant’s summary of Shih but respectfully disagrees that the combination of Shih with Ramachandra does not teach the contested limitations. Although it is true that Shih does not teach “inter-RAT HO”, Ramachandra does (see, for example, paragraphs 0273-0274 of Ramachandra). Moreover, Shih, in the applicant’s words, teaches “selecting an acceptable cell that supports emergency services if the selected cell does not” (Remarks, p. 13). Also, Shih’s description of “fallback mechanisms towards a different RAT” (Shih, 0068) overlaps with Ramachandra’s description of a UE that “selects [a] target cell for recovery” (Ramachandra, 0076), making it obvious to combine their teachings and apply Ramachandra’s recovery methods for inter-RAT handover to support the emergency voice services described in Shih. Thus, the rejection based on Ramachandra in view of Shih is properly maintained.
Later on page 13, the Applicant argues that the combination of Ramachandra and Shih does not teach that “the terminal first searches for a suitable cell; if no suitable cell is found, it selects and accesses an acceptable cell supporting emergency services rather than returning to the source cell [emphasis in original]” (Remarks, p. 13).
However, the Examiner respectfully disagrees. Paragraph 0274 and Fig. 8 of Ramachandra, cited in the non-final rejection, describe a UE that “can receive, from a source node serving a source cell, a command to perform an inter-RAT mobility procedure towards the target cell” (Ramachandra, 0274). Ramachandra adds that “the UE can detect a failure associated with the inter-RAT mobility procedure”, which is analogous to “searching for a suitable cell” because the UE is attempting to connect to a cell (i.e. “searching”) without knowing if it will fail (i.e. if the cell is “suitable”). Ramachandra also describes selecting a fallback cell - i.e. an “acceptable cell” – in the passages cited above (e.g. paragraph 0076 and Fig. 4). Furthermore, Shih contains a complementary description, in the passages cited in the non-final rejection, of “fallback mechanisms towards a different RAT” if a UE’s current serving cell doesn’t provide “Emergency Services” (Shih, 0068). This “fallback” is analogous to the claimed operation of “if no suitable cell is found, select[ing] and access[ing] an acceptable cell supporting emergency services rather than returning to the source cell”. It would be obvious to one of ordinary skill to combine these teachings from Ramachandra and Shih because they both relate to selecting a specific radio access technology to meet a UE’s service requirements. Thus, the rejection based on Ramachandra in view of Shih is properly maintained.
Finally, on pages 14-15 of their remarks, the Applicant contrasts the claim limitation requiring that “in case that a failure of the handover is identified, identifying whether the handover is for emergency service fallback” with paragraph 0097 of Shih, writing, “there is no equivalency between the conditional phrase of ‘in case that a failure of the handover is identified, identifying whether the handover is for emergency service fallback’ and ‘emergency services fallback indicator’” (Remarks, p. 14-15).
However, the Examiner respectfully disagrees. The surrounding context in Shih clarifies that the “emergency services fallback indicator” in Shih is “for UEs camping normally on a cell but failing to register successfully to the network” (Shih, 0096). In other words, the indicator is used if a UE has failed to successfully complete handover to a new cell. Thus, although the reception of the emergency services indicator in Shih is not itself contingent on “a failure of the handover [being] identified”, it is expressly intended for use when handover fails. The UE in Shih will check the emergency services identifiers for other RATs only if it “initiate[s] the Registration procedure ... to receive emergency services” but these services are unavailable in “the current Registration Area”, which corresponds to the contested conditional limitation: “in case that the suitable cell of the second RAT is not available”. In other words, although the emergency services identifier is unconditionally configured, its use is conditional, as in the claimed invention. Thus, the rejection based on Ramachandra in view of Shih is properly maintained.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 19-24, 26-31, and 33-34 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ramachandra (US 2024/0172062 A1, hereinafter “Ramachandra”) in view of Shih et al. (US 2022/0361098 A1, hereinafter “Shih”).
As to Claim 19 and 26:
Ramachandra describes a method to report failure during handover between different radio access technologies.
Specifically, Ramachandra teaches:
Receiving, from a base station of a first radio access technology (RAT), a message to command a handover from the first RAT to a second RAT
Fig. 8 of Ramachandra shows an “inter-RAT mobility procedure” which includes “receiv[ing] ... a command to perform an inter-RAT mobility procedure” (Ramachandra, 0273-0274; Fig. 8).
Performing the handover based on the message
Fig. 8 in Ramachandra and the accompanying description in paragraph 0274 show inter-RAT handover based on a command.
Searching for a suitable cell of the second RAT
Ramachandra describes, in paragraph 0015 and elsewhere, that a UE “receives a handover command to a target cell” (Ramachandra, 0015). Complying with this “handover command” will necessarily entail searching for the “target cell”, i.e. “a suitable cell”, to connect to it.
In case that the suitable cell of the second RAT is not available, selecting an acceptable cell
Fig. 4 in Ramachandra, and the accompanying description in paragraph 0076, describe a UE that “selects [a] target cell for recovery” (i.e. “an acceptable cell”) after detecting a RLF.
Information on the failure of handover is set in a radio link failure (RLF) report
Element 830 of Fig. 8 in Ramachandra describes the UE “sending a failure report, including an indication of the failure cause, to a node serving a cell in which the UE connects”. Elsewhere, Ramachandra also states that “the failure report can be an RLF report” (Ramachandra, 0029).
The RLF report includes information indicating a time elapsed from the failure of handover in the second RAT
Fig. 7 in Ramachandra shows the structure of an example RLF report which includes “TimeSinceFailure-r16”.
Ramachandra does not explicitly disclose:
In case that a failure of the handover is identified, identifying whether the handover is for emergency service fallback
In case that the handover is for the emergency service fallback, searching for a suitable cell
In case that the suitable cell of the second RAT is not available, selecting an acceptable cell of the second RAT supporting an emergency call
However, Shih does describe a method for selecting a backup cell when a UE fails to connect to a preferred cell for an emergency voice call service.
Specifically, Shih teaches:
In case that a failure of the handover is identified, identifying whether the handover is for emergency service fallback
Paragraphs 0096-0097 of Shih teach that “[t]he 5GC may transmit an indication (e.g. the support for emergency services fallback indicator) per RAT” that is used if a UE is “in limited service state” or “camping normally on a cell but failing to register successfully to the network”, which is analogous to “a failure of the handover” (Shih, 0096-0097).
In case that the handover is for the emergency service fallback, searching for a suitable cell
Paragraph 0099 of Shih explains that “[w]hen NR does not support emergency services, RAT fallback towards E-UTRAN connected to 5GC is performed” (Shih, 0099). Here, the determination that “NR does not support emergency services” is analogous to “searching for a suitable cell” and determining that no NR cell supports “emergency services”.
In case that no suitable second RAT cell is available, selecting an acceptable cell of the second RAT supporting an emergency call
Shih explains that “IMS emergency service” can be supported via “fallback mechanisms towards a different RAT” which is analogous to “selecting an acceptable cell of the second RAT supporting an emergency call” if “no suitable second RAT cell is available” (Shih, 0009, 0068).
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the selection of a backup cell during an emergency fallback service, as described in Shih, with Ramachandra’s method for reporting failure during inter-RAT handover. Both procedures yield tangible benefits during inter-RAT handover that are not mutually exclusive, so it would be obvious to apply them both.
Claim 26 describes substantially the same subject matter as Claim 19 in the form of an apparatus claim that additionally requires:
A transceiver; and a controller configured
Fig. 11 in Ramachandra “shows a block diagram of an exemplary wireless device or UE” including “Radio Transceiver 1140” and “Processor(s) 1110” (Ramachandra, 0052).
As to Claim 20 and 27:
Ramachandra teaches:
The time is obtained between the failure of handover and an access to the acceptable cell of the second RAT
Fig. 7 in Ramachandra shows the fields of a RLF report which include “TimeSinceFailure-r16”.
Claim 27 describes substantially the same subject matter as Claim 20 in the form of an apparatus claim.
As to Claim 21 and 28:
Ramachandra teaches:
The first RAT is new radio (NR) and the second RAT is evolved-universal mobile telecommunication systems (UMTS) terrestrial radio access (E-UTRA)
Ramachandra states that “[a]n NR UE can perform handover from ... an NR source cell to ... a target cell that uses another RAT such as LTE (E-UTRA)” (Ramachandra, 0017).
The message includes ...information on a parameter associated with a target cell of the handover
Ramachandra explains that a “command to perform an inter-RAT mobility procedure” will include “a configuration” (which is analogous to one or more “parameters” with handover instructions (Ramachandra, 0020-0022).
Ramachandra does not explicitly disclose:
The message includes information indicating that the handover is triggered by evolved packet system (EPS) fallback for Internet protocol (IP) multimedia subsystem (IMS) voice
However, Shih does teach:
The message includes information indicating that the handover is triggered by evolved packet system (EPS) fallback for Internet protocol (IP) multimedia subsystem (IMS) voice
Ramachandra describes a “NG-RAN” that “can trigger redirection to EPS at QoS Flow establishment for IMS emergency services” (Ramachandra, 0093).
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the selection of a backup cell during an emergency fallback service, as described in Shih, with Ramachandra’s method for reporting failure during inter-RAT handover. Both procedures yield tangible benefits during inter-RAT handover that are not mutually exclusive, so it would be obvious to apply them both.
Claim 28 contains substantially the same subject matter as Claim 21 in the form of an apparatus claim.
As to Claim 22 and 29:
Ramachandra teaches:
Transmitting, to the base station of the first RAT, the RLF report
Ramachandra describes “sending the failure report to the source node” (Ramachandra, 0033).
The RLF report further includes a cell identity (ID) for the acceptable cell and information on a connection failure type
Figure 7 in Ramachandra shows fields of a RLF report, which include “reconnectCellID-r16”.
Claim 29 relates to substantially the same subject matter as Claim 22 in the form of an apparatus claim.
As to Claim 23 and 30:
Ramachandra teaches:
Receiving, from the base station, a user equipment (UE) information request message to request the RLF report
Ramachandra describes a base station sending a “UEInformationRequest message with a flag ‘rlf-ReportReq-r16’” (Ramachandra, 0217).
The RLF report is transmitted via a UE information response message based on the UE information request message
In Ramachandra, the UE responds to the “rlf-ReportReq-r16” flag with a RLF report (Ramachandra, 0217).
Claim 30 contains substantially the same subject matter as Claim 23 in the form of an apparatus claim.
As to Claim 24 and 31:
Ramachandra does not explicitly disclose:
Determining to initiate Internet protocol (IP) multimedia subsystem (IMS) voice
Transmitting, to the base station, information on a connection cause indicating the IMS voice
However, Shih does teach:
Determining to initiate Internet protocol (IP) multimedia subsystem (IMS) voice
Shih states that “the NG_RAN operated by SNPN can trigger handover” for “IMS emergency services (e.g., voice)” (Shih, 0169).
Transmitting, to the base station, information on a connection cause indicating the IMS voice
Ramachandra states that a UE can “set the RRC establishment cause to ‘emergency’ when the UE requests an RRC connection associated to an emergency session” (Ramachandra, 0106).
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the selection of a backup cell during an emergency fallback service, as described in Shih, with Ramachandra’s method for reporting failure during inter-RAT handover. Both procedures yield tangible benefits during inter-RAT handover that are not mutually exclusive, so it would be obvious to apply them both.
Claim 31 describes substantially the same subject matter as Claim 24 in the form of an apparatus claim.
As to Claim 33 and 34:
Ramachandra does not explicitly disclose:
The suitable cell supports a normal service of the second RAT including an Internet protocol (IP) multimedia subsystem (IMS) voice service
The acceptable cell supports a limited service including the emergency call
However, Shih does teach:
The suitable cell supports a normal service of the second RAT including an Internet protocol (IP) multimedia subsystem (IMS) voice service
Shih describes a UE that “supports voice services, emergency services, and/or eCall over IMS” that searches for a “suitable cell” to perform these functions (Shih, 0181).
The acceptable cell supports a limited service including the emergency call
Shih states that a “UE may perform cell (re)selection to an acceptable cell of any available SNPN that supports emergency calls, if no suitable cell is found” (Shih, 0181).
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply Ramachandra’s method for recovering from inter-RAT handover failure to a maintain an acceptable level of service that includes emergency calls, as described in Shih. This combination allows a UE to make emergency calls even when inter-RAT handover fails.
Claim 34 contains substantially the same subject matter as Claim 33 in the form of an apparatus claim.
Claim(s) 25 and 32 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ramachandra (US 2024/0172062 A1) in view of Shih (US 2022/0361098 A1) and further in view of non-patent literature cited in the IDS submitted on 09/15/2023 entitled “Early measurement for EPS Fallback” (hereinafter “Vivo”).
As to Claim 25 and 32:
The combination of Ramachandra and Shih does not explicitly disclose:
Receiving, from the base station, information on at least one carrier frequency of the second RAT
Performing a measurement of the at least one carrier frequency of the second RAT; and
Transmitting, to the base station, a result of the measurement, wherein the message is received after transmitting the result of the measurement
However, Vivo et al. (non-patent literature included in the IDS submitted on 09/15/2023 entitled “Early measurement for EPS Fallback”) does describe methods for a base station to configure a terminal to take and report measurements on a specific set of carrier frequencies during EPS fallback.
Specifically, Vivo teaches:
Receiving, from the base station, information on at least one carrier frequency of the second RAT
Vivo describes a proposal that includes “[i]ntroducing indications on carrier frequency for idle/inactive measurement for EPS Fallback to indicate whether the carrier can be used for EPS Fallback for R17 UEs” (Vivo, p. 3).
Performing a measurement of the at least one carrier frequency of the second RAT; and
Vivo describes a proposal that includes “[i]ntroducing indications on carrier frequency for idle/inactive measurement for EPS Fallback to indicate whether the carrier can be used for EPS Fallback for R17 UEs” (Vivo, p. 3).
Transmitting, to the base station, a result of the measurement, wherein the message is received after transmitting the result of the measurement
Vivo’s “Proposal 1” includes “report of measurement results” for “early measurement for EPS/RAT Fallback based on handover” (Vivo, p. 3).
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to incorporate Vivo’s method of measuring the strength of certain carrier frequencies before handing over into Ramachandra’s method for RLF reporting of inter-RAT handover. Measuring the strength of carrier frequencies helps a UE to determine the best candidate target cell, reducing the risk of failure.
Claim 35 contains substantially the same subject matter as Claim 25 in the form of an apparatus claim.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Jung et al. (US 2016/0119959 A1) describes a method to fall back to an acceptable cell if a suitable cell can’t be found after RLF occurs, Krishnan et al. (US 2024/0049094 A1) describes a method to find a new cell after a failed inter-RAT handover, and non-patent literature Wegmann et al. describes different techniques for ensuring robust mobility in 3G and 4G networks.
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/B.P.W./Examiner, Art Unit 2477
/CHIRAG G SHAH/Supervisory Patent Examiner, Art Unit 2477