DETAILED ACTION
Response to Amendment
The amendment filed 9/11/2026 has been entered. Claims 1-2, 5-11, 14-19 remain pending in the application. Applicant’s amendment has overcome the objection to the specification set forth in the Non-Final Office Action mailed 6/11/2026 (“FAOM”), which is withdrawn.
Response to Argument
Applicant’s arguments, pages 7-16 of the Remarks filed 9/11/2026 (“Remarks”), have been fully considered but are moot because the new ground(s) of rejection(s), necessitated by the applicant's amendment, do not rely on the combination of references applied in the prior rejection of record.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 5-8, 10, 14-17 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by U.S. Patent Application Publication No. 2023/0179168, published 6/8/2023 (“Sevskiy”).
Sevskiy discloses in Fig. 4, annotated below, and the corresponding description:
Claims 1 and 10
a filter (Fig. 4, filter circuit 400, ¶¶39-46) comprising:
a first port (480 or alternatively, as annotated),
a second port (482 or alternatively, as annotated) and
at least one filtering unit (filter stage(s) 402 of filtering circuit 400, either individually, or in BPF 453 or BPF 457 or both), wherein
each filtering unit of the at least one filtering unit comprises a T network (each filter stage 402 comprises a T-network including capacitors 408, 412, 416 and inductors 414, 418) and a resonator (acoustic resonator 410);
the T network comprises a first capacitive element (408), a second capacitive element (412) and a first element (as annotated, comprising 414, 416, 418);
the first capacitive element (408) and the second capacitive element (412) are connected in series between the first port (480) and the second port (482), the first element is connected to a node (annotated) between the first capacitive element and the second capacitive element, and the resonator (410) is connected in parallel with the T network (Fig. 4); and
wherein the first element comprises a first inductive element (418) and a third capacitive element (416), and a circuit formed by the first inductive element and the third capacitive element connected in series is connected to the node (Fig. 4).
Regarding claim 10, Sevskiy discloses a multiplexer (Fig. 4, duplexer 451) comprising a plurality of filters as recited in claim 1 (¶44). In the multiplexer configuration, each of the BPF 453 and 457 may include a filter circuit 400 (¶44) including first, second and fourth ports, as annotated.
Claims 5 and 14
further comprising an LC filtering unit (filter stages 404 or 490), wherein the LC filtering unit and the at least one filtering unit (402) are connected in series between the first port and the second port (Fig. 4).
Claims 6 and 15
wherein the filter comprises at least two filtering units (filter stages 402 and 404), and the at least two filtering units are connected in series between the first port (480) and the second port (482) (Fig. 4).
In addition, Sevskiy discloses duplexer 451 including BPF 453 and BPF 457, each including a filter circuit 400 (¶44). That is, BPF 453 may include a first filtering unit (for example, filter stage 402) and BPF 457 may include a second filtering unit (for example, another filter stage 402) connected in series between the first port and the second port, as annotated (Fig. 4).
Claims 7 and 16
further comprising a fourth port (Fig. 4, “ANT”) provided between the at least two filtering units (filter stage 402 of BPF 453 and another filter stage 402 of BPF 457).
Claims 8 and 17
wherein the filter further comprises an LC filtering unit (each BPF 453 and BPF 457 of duplexer 451 include a filter stage 490) connected in series between the at least two filtering units (filter stage 402 of BPF 453 and another filter stage 402 of BPF 457).
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Claim Rejections - 35 USC § 103
Claims 1 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over CN109672422A (“Wang”), of record, taken alone.
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Regarding claims 1 and 10, Wang discloses in Figs. 2-3, 6-7, 10 and the corresponding description:
a filter (Figs. 2-3, 6-7) comprising:
a first port (port A),
a second port (port B) and
at least one filtering unit (components connected between Ports A and B), wherein
each filtering unit of the at least one filtering unit comprises a T network (Fig. 3: C1, C2, C4, L3; Fig. 7: C7, C8, C9, L9) and a resonator (Fig. 3, resonator 11; Fig. 7, resonator 12);
the T network comprises a first capacitive element (Fig. 3: C1; Fig. 7: C7), a second capacitive element (Fig. 3: C2; Fig. 7: C8) and a first element (Fig. 3: C4 and L3; Fig. 7: C9 and L9);
the first capacitive element and the second capacitive element are connected in series between the first port and the second port, the first element is connected to a node (Figs. 3, 7, annotated) between the first capacitive element and the second capacitive element, and
the resonator (Fig. 3: resonator 11; Fig. 7: resonator 12) is connected in parallel with the T network (Fig. 3, resonator 11 is connected in parallel with C1 and C2; Fig. 7: not connected in parallel);
wherein the first element comprises a first inductive element (Fig. 3: L3; Fig. 7: L9) and a third capacitive element (Fig. 3: C4; Fig. 7: C9), and
a circuit formed by the first inductive element and the third capacitive element connected in series (Fig. 3: connected in parallel; Fig. 7: connected in series) is connected to the node (Figs. 3, 7; both circuits are connected to the node).
To summarize, the embodiment of Fig. 3, discloses the resonator connected in parallel with the T-network but does not disclose an in-series connection in the first element, while the embodiment of Fig. 7 does not disclose the resonator connected in parallel with the T-network but disclose the in-series connection in the first element.
Regarding the embodiment of Fig. 3, Wang also teaches that “[t]he first resonant unit 101, the second resonant unit 102 [which corresponds to the claimed first element as described above], and the third resonant unit 103 can be composed of a single circuit element or at least two circuit elements, such as a capacitor, an inductor, or a resistor, or a series-parallel combination of at least two of the capacitors, inductors, and resistors” (¶57) (emphasis added).
Thus, while Wang does not explicitly disclose the first element including an in-series connection in the embodiment of Fig. 3, Wang fairly suggests that a first inductive element (L3) and a third capacitive element (C4) may be connected in series and connected to the node (¶57).
As a result, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the embodiment of Fig. 3 by replacing its parallel connection with the in-series connection of Fig. 7 because Wang discloses all the claimed elements in Fig. 3, identifies a number of predictable solutions (either parallel or in series connections) (¶57), and actually discloses the in-series connection in Fig. 7. See MPEP 2143.I.E (citing KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007)); see also Boston Scientific Scimed, Inc. v. Cordis Corp., 554 F.3d 982 (Fed. Cir. 2009) (holding that two embodiments disclosed in the prior art patent together rendered [the claimed invention] obvious).
Alternatively, or in addition, it would have been obvious to have modified the embodiment of Fig. 7 of Wang by adding a resonator connected in parallel with the T network as disclosed in the embodiment of Fig. 3 for the benefit of smaller transition band bandwidth and higher suppression characteristics, as taught by Wang (Fig. 4; ¶61). MPEP 2143.I.G.
Regarding claim 10, Wang discloses a multiplexer (Fig. 10, ¶¶80-82) comprising a plurality of filters as recited in claim 1 (Filters 10s and 20s).
Claims 1-2, 10-11, 19 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent No. 2,002,216, issued 5/21/1935 (“Bode”) in view of Sevskiy or Wang.
Bode discloses in Figs. 6-7 and the corresponding description:
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Claims 1 and 10
a filter (Fig. 6, high-pass filter; Fig. 7, band-pass filter; col. 5, lines 50-70) comprising:
a first port (1),
a second port (3) and
at least one filtering unit (components connected between Ports 1 and 3), wherein
each filtering unit of the at least one filtering unit comprises a T network (Fig. 6: C1s, C2, L2; Fig. 7: L1s, C1s, L2, C2);
the T network comprises a first capacitive element (Fig. 6, annotated), a second capacitive element (Fig. 6, annotated) and a first element (L2 and C2);
the first capacitive element (C1) and the second capacitive element (C1) are connected in series between the first port (1) and the second port (3), the first element is connected to a node (Fig. 6, annotated) between the first capacitive element and the second capacitive element; and
wherein the first element comprises a first inductive element (L2) and a third capacitive element (C2), and a circuit formed by the first inductive element and the third capacitive element connected in series is connected to the node (Figs. 6-7).
Bode does not disclose a resonator connected in parallel with the T network.
However, as set forth above, either Sevskiy (Fig. 4, resonator 410) or Wang (Fig. 3, resonator 11) disclose the resonator connected in parallel with the T network.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the filter of Bode by adding a resonator connected in parallel with the T network for the benefit of introducing an additional rejection notch, as taught by Sevskiy (Figs. 7A-B, 10A-B, ¶¶59, 61) or for the benefit of smaller transition band bandwidth and higher suppression characteristics, as taught by Wang (Fig. 4; ¶61).
Regarding claim 10, Bode in view of Sevskiy or Wang discloses a multiplexer comprising a plurality of filters as recited in claim 1 (Sevskiy, Fig. 4, duplexer 451; Wang, Fig. 10, ¶¶80-82).
Regarding claims 2 and 11, Bode in view of Sevskiy or Wang discloses wherein a first terminal of the first inductive element is connected to the node, a second terminal of the first inductive element is connected to the first terminal of the third capacitive element, and a second terminal of the third capacitive element serves a third port (port 2 or 4) of the filter (Bode, Figs. 6-7).
Regarding claim 19, Bode in view of Sevskiy discloses wherein the filter comprises at least two filtering units (for example, filter stage 402 of BPF 453 and filter stage 402 of BPF 457 of multiplexer 451), and the at least two filtering units are connected in series between the first port and the second port, as annotated.
Claims 9 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Sevskiy in view of A. Zverev, Handbook of Filter Synthesis, 1967 (“Zverev”).
As set forth above (see rejection of claims 1 and 6), Sevskiy discloses all the limitations of claim 9 except “wherein transmission zeros of different filtering units of the at least two filtering units correspond to equal frequencies.”
However, Zverev, in the same field of endeavor, discloses filters comprising cascaded identical filtering sections, that is, different filtering units with transmission zeros corresponding to equal frequencies (pp. 76, 489, Fig. 8.61) and teaches that filters containing identical sections is “ordinarily the simplest to build” (p. 76, 490). Zverev also acknowledges some disadvantages and notes that non-identical sections may give better spurious control (pp. 76, 490). Thus, Zverev discloses two design alternatives and affirmatively endorses identical sections with an expressly stated advantage--design and implementation simplicity. Zverev also describes potential tradeoffs (simplicity vs. better spurious control), rather than rejecting identical sections as unsuitable. A discussion of other alternatives and their benefits does not constitute teaching away. MPEP 2145. D.1.
Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the filter/multiplexer of Sevskiy by having transmission zeros of different cascaded filtering units correspond to equal frequencies for the benefits of simpler filter design and implementation, as taught by Zverev (pp. 76, 488-490).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to VICTOR COLE, telephone number (571) 272-4686. The examiner can be reached Monday-Friday, 9AM-5PM ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, ANDREA LINDGREN BALTZELL, can be reached at (571) 272-5918. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/VICTOR COLE/
Examiner, Art Unit 2843
/ANDREA LINDGREN BALTZELL/Supervisory Patent Examiner, Art Unit 2843
