Prosecution Insights
Last updated: July 17, 2026
Application No. 18/218,867

DUPLEXER WITH BALANCED IMPEDANCE LADDER

Final Rejection §103
Filed
Jul 06, 2023
Priority
Jun 30, 2020 — divisional of 11/368,181 +1 more
Examiner
TALUKDER, MD K
Art Unit
2648
Tech Center
2600 — Communications
Assignee
Apple Inc.
OA Round
2 (Final)
80%
Grant Probability
Favorable
3-4
OA Rounds
0m
Est. Remaining
94%
With Interview

Examiner Intelligence

Grants 80% — above average
80%
Career Allowance Rate
664 granted / 830 resolved
+18.0% vs TC avg
Moderate +14% lift
Without
With
+14.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 5m
Avg Prosecution
31 currently pending
Career history
857
Total Applications
across all art units

Statute-Specific Performance

§101
1.2%
-38.8% vs TC avg
§103
91.8%
+51.8% vs TC avg
§102
3.9%
-36.1% vs TC avg
§112
0.5%
-39.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 830 resolved cases

Office Action

§103
Notice of Pre-AIA or AIA Status 1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . 2. It would be of great assistance to the office if all incoming papers pertaining to a filed application carried the following items: i. Application number (checked for accuracy, including series code and serial no.). ii. Group art unit number (copied from most recent Office communication). iii. Filing date. iv. Name of the examiner who prepared the most recent Office action. v. Title of invention. vi. Confirmation number (See MPEP § 503). Response to Arguments 3. Applicant's arguments with respect to claims have been considered but are moot in view of the new ground(s) of rejection. 4. The Examiner has pointed out particular references contained in the prior art of record within the body of this action for the convenience of the Applicant. Although the specified citations are representative of the teachings in the art and are applied to the specific limitations within the individual claim, other passages, paragraph and figures may apply. Applicant, in preparing the response, should consider fully the entire reference as potentially teaching all or part of the claimed invention, as well as the context of the passage as taught by the prior art or disclosed by the Examiner. 5. Claim interpretation: When multiple limitations are connected with “OR”, one of the limitations doesn’t have any patentable weight since both of the limitations are optional. Claim Rejection- 35 USC § 103 6. The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102 of this title, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claims 1, 2, 7, 21-23 & 28 are rejected under 35 U.S.C. 103 as being unpatentable over Anderson et al (Pub No. US 2018/0191396) and further in view of Lin et al (Pub No. 2014/0287699). Regarding claim 1, Anderson et al discloses a duplexer comprising: a transmitter port coupled configured to couple to transmitter circuitry of an electronic device (Fig. 1: duplexer-112 with connection point connecting the transmitter-108) & (Para. 27-28); and a plurality of transmitter impedance devices configured to couple the transmitter port to one or more antennas of the electronic device (Fig. 1 & 2 & 3: Multiple Tx impedance-214/ 216 connected to antenna-206) & (Para. 61 & 63 & 67). Anderson et al does not explicitly disclose transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the plurality of transmitter impedance devices. In a similar field of endeavor, Lin et al discloses transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the plurality of transmitter impedance devices (Fig. 4-5) & (Para. 61 & 66-68: One of the impedance-333/335 selectively connected to the transmission circuit for selection of the transmission impedance). Therefore, it would have been obvious to one of the ordinary skilled in the art before the effective filing date of the invention to use the RF front end module of Lin’s disclosure with the, transmission leakage reduction system, as taught by Anderson. Doing so would have resulted in effectively controlling the transmission impedance based on the frequency ranges to reduce extra loss in the transmitter path. Regarding claim 2, Anderson et al discloses the transmitter port is configured to provide a transmission signal from the transmitter circuitry to the one or more antennas based on the plurality of transmitter impedance devices coupling the transmitter port to the one or more antennas during a transmission mode (Fig. 1 & 2 & 3: Tx impedance-214/ 216 connection to antenna-206 provide a transmission signal from the transmitter circuitry) & (Para. 61 & 63 & 67). Regarding claim 7, Anderson et al discloses a transmitter bridge configured to couple the transmitter port to a ground terminal during the transmission mode (Fig. 7: transceiver-700 connected to the ground). Regarding claim 21, Anderson et al discloses isolation circuitry comprising: a transmitter port coupled configured to couple to transmitter circuitry of an electronic device (Fig. 1: duplexer-112 with connection point connecting the transmitter-108) & (Para. 27-28); and a plurality of transmitter impedance devices configured to couple the transmitter port to one or more antennas of the electronic device (Fig. 1 & 2 & 3: Multiple Tx impedance-214/ 216 connected to antenna-206) & (Para. 61 & 63 & 67). Anderson et al does not explicitly disclose transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the plurality of transmitter impedance devices. In a similar field of endeavor, Lin et al discloses transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the plurality of transmitter impedance devices (Fig. 4-5) & (Para. 61 & 66-68: One of the impedance-333/335 selectively connected to the transmission circuit for selection of the transmission impedance). Therefore, it would have been obvious to one of the ordinary skilled in the art before the effective filing date of the invention to use the RF front end module of Lin’s disclosure with the, transmission leakage reduction system, as taught by Anderson. Doing so would have resulted in effectively controlling the transmission impedance based on the frequency ranges to reduce extra loss in the transmitter path. Regarding claim 22, Anderson et al discloses a receiver port coupled configured to couple to receiver circuitry of the electronic device (Fig. 1: receiver connected to duplexer); and a plurality of receiver impedance devices configured to couple the receiver port to the one or more antennas of the electronic device (Fig. 1: receiver connected to duplexer and antenna-104). Regarding claim 23, Anderson et al discloses the plurality of receiver impedance devices are configured to couple the receiver port to the one or more antennas during a reception mode (Fig. 1: Antenna connected to receiver via duplexer), the receiver port being configured to provide a reception signal from the one or more antennas to the receiver circuitry based on the plurality of receiver impedance devices coupling the receiver port to the one or more antennas during the reception mode (Fig. 1-2: Reception signal from antennas based on the plurality of receiver impedance coupling to the antennas). Regarding claim 28, Anderson et al discloses an electronic device comprising: transmitter circuitry (Fig. 1-2: Transmitter circuitry); a first port coupled to the transmitter circuitry (Fig. 1: duplexer-112 with connection point connecting the transmitter-108) & (Para. 27-28); and a first set of impedance devices configured to couple the first port to at least one antenna of the electronic device (Fig. 1 & 2 & 3: Multiple Tx impedance-214/ 216 connected to antenna-206) & (Para. 61 & 63 & 67). Anderson et al does not explicitly disclose transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the first set of impedance devices. In a similar field of endeavor, Lin et al discloses transmitter impedance devices couple the transmitter during a transmission mode according to respective impedances of the first set of impedance devices (Fig. 4-5) & (Para. 61 & 66-68: One of the impedance-333/335 selectively connected to the transmission circuit for selection of the transmission impedance). Therefore, it would have been obvious to one of the ordinary skilled in the art before the effective filing date of the invention to use the RF front end module of Lin’s disclosure with the, transmission leakage reduction system, as taught by Anderson. Doing so would have resulted in effectively controlling the transmission impedance based on the frequency ranges to reduce extra loss in the transmitter path. Claims 3, 4, 5 & 24 are rejected under 35 U.S.C. 103 as being unpatentable over Anderson et al (Pub No. US 2018/0191396), in view of Lin et al (Pub No. 2014/0287699) and further in view of Zhu et al (Pub No. 2016/0105210). Regarding claim 3, Anderson et al discloses a receiver port coupled configured to couple to receiver circuitry of the electronic device (Fig. 1: Receiver circuity connected to the duplexer port). Anderson et al does not explicitly disclose a plurality of receiver impedance devices configured to uncouple the receiver port from the one or more antennas during the transmission mode. In a similar field of endeavor, Zhu et al discloses a plurality of receiver impedance devices configured to uncouple the receiver port from the one or more antennas during the transmission mode (Fig. 1A & Fig. 2: impedance devices- matching network & uncouple the receiver port-204 from antennas during the Tx mode). At the time of filling, it would have been obvious to use transmitter and receiver switching system to transfer the desire signal properly by using wireless device. Regarding claim 4, Anderson et al discloses the plurality of transmitter impedance devices is serially coupled to the plurality of receiver impedance devices (Fig. 3: impedance-315/317 serially coupled & Para. 13 & 67). Regarding claim 5 & 24, Anderson et al discloses the plurality of receiver impedance devices is configured to reduce insertion loss of the transmission signal (Para. 76: reduce insertion loss of the transmission signal). Anderson is silent regarding isolate the receiver port from the transmitter port during the transmission mode by causing 0 Volts across the receiver port Zhu et al discloses isolate the receiver port from the transmitter port during the transmission mode by causing 0 Volts across the receiver port (Fig. 1A & Fig. 2: disconnect the receiver port-204 from antennas during the Tx mode & Para. 46). At the time of filling, it would have been obvious to use transmitter and receiver switching system to transfer the desire signal properly by using wireless device. Claims 6, 8, 25 & 27 are rejected under 35 U.S.C. 103 as being unpatentable over Anderson et al (Pub No. US 2018/0191396), in view of Lin et al (Pub No. 2014/0287699) and further in view of Komiak et al (Pub No. 2018/0183396). Regarding claim 6 & 25, Anderson et al discloses the plurality of transmitter impedance devices comprises a first transmitter impedance device, a second transmitter impedance device, a third transmitter impedance device, and a fourth transmitter impedance device (Fig. 3: Plurality of impedance-Z1-Z22). Anderson et al is silent regarding the plurality of transmitter impedance devices being configured to operate in the transmission mode based on a first ratio of a first impedance of the first transmitter impedance device to a second impedance of the second transmitter impedance device being different from a second ratio of a third impedance of the third transmitter impedance device to a fourth impedance of the fourth transmitter impedance device. Komiak et al discloses the plurality of transmitter impedance devices being configured to operate in the transmission mode based on a first ratio of a first impedance of the first transmitter impedance device to a second impedance of the second transmitter impedance device being different from a second ratio of a third impedance of the third transmitter impedance device to a fourth impedance of the fourth transmitter impedance device (Para. 4-5: high input impedance and low input impedance having different ratio of impedance. System can use multiple different impedance). At the time of filling, it would have been obvious to use multiple several impedances to adjust impedance in the transceiver to control proper signal in the system. Regarding claim 8 & 27, Anderson is silent regarding the plurality of transmitter impedance devices is configured to operate in an unbalanced state during the transmission mode, the unbalanced state comprising an unequal ratio of impedances of the plurality of transmitter impedance devices. Komiak et al discloses the plurality of transmitter impedance devices is configured to operate in an unbalanced state during the transmission mode, the unbalanced state comprising an unequal ratio of impedances of the plurality of transmitter impedance devices (Para. 4-5: high input impedance and low input impedance having different ratio of impedance. System can use multiple different impedance). At the time of filling, it would have been obvious to use multiple several impedances to adjust impedance in the transceiver to control proper signal in the system. Claims 26 are rejected under 35 U.S.C. 103 as being unpatentable over Anderson et al (Pub No. US 2018/0191396), in view of Lin et al (Pub No. 2014/0287699), in view of Zhu et al (Pub No. 2016/0105210) and further in view of Komiak et al (Pub No. 2018/0183396). Regarding claim 26, Anderson et al is silent regarding a transmitter bridge configured to uncouple the transmitter port from the one or more antennas during a reception mode based on a first ratio of a first impedance of a first transmitter impedance device of the plurality of transmitter impedance devices to a second impedance of a second transmitter impedance device of the plurality of transmitter impedance devices correlating to a second ratio of a third impedance of a third transmitter impedance device of the plurality of transmitter impedance devices to a fourth impedance of a fourth transmitter impedance device of the plurality of transmitter impedance devices. Zhu et al discloses a transmitter bridge configured to uncouple the transmitter port from the one or more antennas during a reception mode based on a first ratio of a first impedance of a first transmitter impedance device (Fig. 2: Switch 204 can uncouple the transmitter port from antennas during a reception mode based impedance). Anderson et al is silent regarding a first transmitter impedance device of the plurality of transmitter impedance devices to a second impedance of a second transmitter impedance device of the plurality of transmitter impedance devices correlating to a second ratio of a third impedance of a third transmitter impedance device of the plurality of transmitter impedance devices to a fourth impedance of a fourth transmitter impedance device of the plurality of transmitter impedance devices. Komiak et al discloses a first transmitter impedance device of the plurality of transmitter impedance devices to a second impedance of a second transmitter impedance device of the plurality of transmitter impedance devices correlating to a second ratio of a third impedance of a third transmitter impedance device of the plurality of transmitter impedance devices to a fourth impedance of a fourth transmitter impedance device of the plurality of transmitter impedance devices (Para. 4-5: high input impedance and low input impedance having different ratio of impedance. System can use multiple different impedance). At the time of filling, it would have been obvious to use multiple several impedances to adjust impedance in the transceiver to control proper signal in the system. Claims 29-32 are rejected under 35 U.S.C. 103 as being unpatentable over Anderson et al (Pub No. US 2018/0191396), in view of Lin et al (Pub No. 2014/0287699) and further in view of Toda et al (Pat No. 7512384). Regarding claim 29, Anderson et al discloses transmit data from the transmitter circuitry using the at least one antenna (Fig. 1-2). Anderson et al is silent regarding set a first impedance gradient and a second impedance gradient of the first set of impedance devices to a first impedance state, set a first impedance tuner and a second impedance tuner of the first set of impedance devices to a second impedance state. Toda et al discloses set a first impedance gradient and a second impedance gradient of the first set of impedance devices to a first impedance state, set a first impedance tuner and a second impedance tuner of the first set of impedance devices to a second impedance state (Col. 7 Line 1-20: impedance tuned and adjusted and impedance gradient will have different state). At the time of filling, it would have been obvious to use impedance adjusting system to tune the impedance at a proper level to control the transmitter device properly. Regarding claim 30, Anderson et al is silent regarding setting the first impedance gradient and the second impedance gradient to the first impedance state and the first impedance tuner and the second impedance tuner to the second impedance state causes the first port to couple to the at least one antenna. Toda et al discloses setting the first impedance gradient and the second impedance gradient to the first impedance state and the first impedance tuner and the second impedance tuner to the second impedance state causes the first port to couple to the at least one antenna (Col. 7 Line 1-20: impedance tuned and adjusted and impedance gradient will have different state & Fig. 1: Antenna 102 controlled by the controller). At the time of filling, it would have been obvious to use impedance adjusting system to tune the impedance at a proper level to control the transmitter device properly. Regarding claim 31, Anderson et al discloses more processors being configured to set the second set of impedance devices to the second impedance state (Fig. 2-3: impedance devices having multiple impedance state). Anderson is silent regarding receiver circuitry; a second port coupled to the receiver circuitry; and a second set of impedance devices configured to couple the second port to the at least one antenna, the one or more processors being configured to set the second set of impedance devices to the second impedance state, causing the second port to uncouple from the at least one antenna. Zhu et al discloses receiver circuitry; a second port coupled to the receiver circuitry; and a second set of impedance devices configured to couple the second port to the at least one antenna, the one or more processors being configured to set the second set of impedance devices to the second impedance state, causing the second port to uncouple from the at least one antenna (Fig. 2: RF switch port couple to receiving circuit to select one of the antenna and setup impedance state for the receiving device) & (Para. 46). At the time of filling, it would have been obvious to use impedance adjusting system to tune the impedance at a proper level for receiving the desire signals in the RF unit. Regarding claim 32, Anderson et al discloses the first set of impedance devices is serially coupled to the second set of impedance devices, the first impedance state comprising a greater impedance than the second impedance state (Fig. 3: impedance-315/317 serially coupled & Para. 13 & 67-68: One impedance state has greater impedance than the others). At the time of filling, it would have been obvious to use impedance adjusting system to tune the impedance at a proper level for receiving the desire signals in the RF unit. Another Prior Art 7. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Ansari (US 8964605) discloses RF transceiver having impedance selection system and select impedance during transmission mode based on the system requirements. CONCLUSION 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 extension fee 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 date of this final action. Any inquiry concerning this communication from the examiner should be directed to Patent Examiner Md Talukder whose telephone number is (571) 270-3222. The examiner can normally be reached on Mon-Th 8:00 am to 4:30 pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisors, Wesley Kim can be reached on 571-272-7867. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /MD K TALUKDER/ Primary Examiner, Art Unit 2648
Read full office action

Prosecution Timeline

Jul 06, 2023
Application Filed
Feb 08, 2024
Response after Non-Final Action
Jan 29, 2026
Non-Final Rejection mailed — §103
Apr 28, 2026
Response Filed
Jul 07, 2026
Final Rejection mailed — §103 (current)

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Prosecution Projections

3-4
Expected OA Rounds
80%
Grant Probability
94%
With Interview (+14.1%)
2y 5m (~0m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 830 resolved cases by this examiner. Grant probability derived from career allowance rate.

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