DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on February 23, 2026 has been entered.
Response to Amendment
The Amendment filed February 23, 2026 has been entered. Claims 1, 3-12, and 14-20 remain pending in the application.
Response to Arguments
Applicant's arguments filed February 23, 2026 have been fully considered but they are not persuasive.
Applicant argues, see pages 6-7, that previously presented prior art reference Honda et al. (Patent Publication Number JP 2020/205576 A), hereafter referred to as Honda, fails to disclose “the differential inverter . . . to behave as an open circuit at even harmonics of the operating frequency”, as claimed in the independent claims. Examiner respectfully disagrees.
Honda discloses the differential inverter behaves as a class inverse F amplifier (Honda, Page 8, Paragraphs 8-9). The definition of a class inverse F amplifier is that it provides a short circuit at odd harmonics of the operating frequency and an open circuit at even harmonics of the operating frequency, as described in related art reference Koya (Patent Publication Number US 2017/0310287 A1), hereafter referred to as Koya (Koya, Paragraph 27, lines 12-16, “On the other hand, the amplifier 130 performs inverse-class-F operation as a result of the input impedance of the harmonic-termination circuit 140 being controlled such that odd-ordered harmonics are short-circuited and even-ordered harmonics experience an open circuit”). Therefore, one of ordinary skill in the art would have understood the class inverse F amplifier of Honda to provide an open circuit at even harmonics of the operating frequency. Therefore, applicant’s arguments are unconvincing and the rejections of claims 1, 3-12, and 14-20 are maintained.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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, 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 1-3, 6-14, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Zong et al. “A 28-GHz SOI-CMOS Doherty Power Amplifier With a Compact Transformer-Based Output Combiner”, hereafter referred to as Zong, in view of Honda and Park et al. (Patent Publication Number US 2023/0336126 A1), hereafter referred to as Park.
Regarding claim 1, Zong discloses:
A Doherty power amplifier (Zong, Figs. 2C and 7A) comprising: an input (Fig. 7A, see input of Quadrature power splitter) configured to receive an input signal to be amplified (Fig. 7A, see input of Quadrature power splitter) and to split the input signal into a first portion (Fig. 7A, see connection between Quadrature power splitter and Main driver) and a second portion (Fig. 7A, see connection between Quadrature power splitter and Aux. driver), the input signal having an operating frequency (Page 6, Col. 1, Section A, lines 1-4); a carrier amplifier path coupled to the input to receive the first portion (Fig. 7A, see connection between Quadrature power splitter and Main driver), the carrier amplifier path including a carrier amplifier coupled to a differential inverter (Fig. 2C, see connection between Main amplifier and LC impedance inverter), the carrier amplifier being configured to amplify the first portion and provide an amplified first portion to the differential inverter (Fig. 2C, see connection between Main amplifier and LC impedance inverter), the capacitance coupling a first path and a second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors); a second capacitance coupling the first path and the second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors); and a peaking amplifier path coupled to the input to receive the second portion (Fig. 7A, see connection between Quadrature power splitter and Aux. driver) and comprising a peaking amplifier configured to amplify the second portion (Fig. 2C, see Aux amplifier), but fails to disclose the differential inverter having a capacitance configured to make the differential inverter behave as a short circuit at odd harmonics of the operating frequency and to behave as an open circuit at even harmonics of the operating frequency, the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Honda teaches the differential inverter having a capacitance (Honda, Fig. 6, 3011A) configured to make the differential inverter behave as a short circuit at odd harmonics of the operating frequency (Page 8, Paragraphs 8-9) and to behave as an open circuit at even harmonics of the operating frequency (Page 8, Paragraph 9, lines 1-2), but fails to teach the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Park teaches the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel (Park, Fig. 3, see capacitor common to LC networks 340 and 350).
Zong, Honda, and Park are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Honda and Park to modify the capacitance of Zong to make the differential inverter of Zong behave as a short circuit at odd harmonics and an open circuit at even harmonics of the operating frequency, which would have the effect of improving the efficiency of the amplifier of Zong (Honda, Page 8, Paragraph 9), and to place the LC network of Zong in the position of the LC network of Park, which would have the effect of reducing the required circuit area (Park, Paragraph 62, lines 1-8).
Regarding claim 3, Zong fails to disclose:
wherein the carrier amplifier is a class inverse F amplifier.
However, Honda teaches wherein the carrier amplifier is a class inverse F amplifier (Page 8, Paragraphs 8-9).
Zong, Honda, and Park are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Honda to modify the capacitance of Zong to make the carrier amplifier of Zong behave as a class inverse F amplifier, which would have the effect of improving the efficiency of the amplifier of Zong (Honda, Page 8, Paragraph 9).
Regarding claim 6, Zong further discloses:
wherein the capacitance is configured to provide a phase shift to the amplified first portion (Zong, Page 3, Col. 1, lines 8-12).
Regarding claim 7, Zong further discloses:
wherein the phase shift is a 90 degree phase shift (Zong, Page 3, Col. 1, lines 6-12 [capacitances configured to provide phase shift equivalent to λ/4 transmission lines]).
Regarding claim 8, Zong further discloses:
wherein the first path and the second path each include an inductance (Zong, Fig. 2C, see inductances on both paths between capacitances), the second capacitance being located after each of the inductances of the first path and the second path (Fig. 2C, see capacitance located after inductances).
Regarding claim 9, Zong further discloses:
wherein the differential inverter is configured to output an inverted amplified first portion (Zong, Page 3, Col. 1, lines 8-12) and the Doherty power amplifier further comprises a balanced to unbalanced matching circuit (Page 3, Col. 1, lines 8-10).
Regarding claim 10, Zong further discloses:
wherein the carrier amplifier path comprises a carrier amplifier path output configured to output an inverted amplified first portion (Zong, Fig. 2C, see that output of Main amplifier passes through impedance inverter before reaching combiner) and the peaking amplifier path comprises a peaking amplifier output configured to output an amplified second portion (Fig. 2C, see connection between output of Aux amplifier and combiner).
Regarding claim 11, Zong further discloses:
further comprising a combiner (Zong, Fig. 2C, see transformers) coupled to the carrier amplifier path output (Fig. 2C, see connection between transformer and Main amplifier) and the peaking amplifier output (Fig. 2C, see connection between transformer and Aux amplifier) and being configured to combine the inverted amplified first portion and the amplified second portion to yield an amplified radio-frequency signal (Fig. 2C, see that outputs of Main and Aux amplifiers combine at transformers to yield single-ended output signal).
Regarding claim 12, Zong discloses:
A method of amplifying a radio-frequency signal (Zong, Figs. 2C and 7A), the method comprising: receiving a radio-frequency signal at an input of a Doherty power amplifier (Fig. 7A, see input of Quadrature power splitter), the radio-frequency signal having an operating frequency; splitting the radio-frequency signal into a first portion and a second portion (Page 6, Col. 1, Section A, lines 1-4); providing the first portion to a carrier amplifier path (Fig. 7A, see connection between Quadrature power splitter and Main driver) and the second portion to a peaking amplifier path (Fig. 7A, see connection between Quadrature power splitter and Aux. driver); amplifying the first portion at a carrier amplifier on the carrier amplifier path (Fig. 2C, see Main amplifier) and providing an amplified first portion to a differential inverter on the carrier amplifier path (Fig. 2C, see connection between Main amplifier and LC impedance inverter), the capacitance coupling a first path and a second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors); and amplifying the second portion at a peaking amplifier on the peaking amplifier path to provide an amplified second portion (Fig. 2C, see Aux amplifier), the peaking amplifier path including a second capacitance coupling the first path and the second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors) but fails to disclose the differential inverter having a capacitance making the differential inverter behave as a short circuit at odd harmonics of the operating frequency and to behave as an open circuit at even harmonics of the operating frequency, and [the second capacitance] coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Honda teaches the differential inverter having a capacitance (Honda, Fig. 6, 3011A) making the differential inverter behave as a short circuit at odd harmonics of the operating frequency (Page 8, Paragraphs 8-9) and to behave as an open circuit at even harmonics of the operating frequency (Page 8, Paragraph 9, lines 1-2), but fails to disclose and [the second capacitance] coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Park teaches and [the second capacitance] coupling a third path and a fourth path of the peaking amplifier in parallel (Park, Fig. 3, see capacitor common to LC networks 340 and 350).
Zong, Honda, and Park are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Honda and Park to modify the capacitance of Zong to make the differential inverter of Zong behave as a short circuit at odd harmonics and an open circuit at even harmonics of the operating frequency, which would have the effect of improving the efficiency of the amplifier of Zong (Honda, Page 8, Paragraph 9), and to place the LC network of Zong in the position of the LC network of Park, which would have the effect of reducing the required circuit area (Park, Paragraph 62, lines 1-8).
Regarding claim 14, Zong fails to disclose:
wherein the carrier amplifier is a class inverse F amplifier.
However, Honda teaches wherein the carrier amplifier is a class inverse F amplifier (Page 8, Paragraphs 8-9).
Zong, Honda, and Park are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Honda to modify the capacitance of Zong to make the carrier amplifier of Zong behave as a class inverse F amplifier, which would have the effect of improving the efficiency of the amplifier of Zong (Honda, Page 8, Paragraph 9).
Regarding claim 16, Zong further discloses:
wherein the capacitance provides a phase shift to the amplified first portion (Zong, Page 3, Col. 1, lines 8-12).
Regarding claim 17, Zong further discloses:
wherein the first path and the second path each include an inductance (Zong, Fig. 2C, see inductances on both paths between capacitances), the second capacitance being located after each of the inductances of the first path and the second path (Fig. 2C, see capacitance located after inductances).
Regarding claim 18, Zong further discloses:
wherein the carrier amplifier path comprises a carrier amplifier path output for outputting an inverted amplified first portion (Zong, Fig. 2C, see that output of Main amplifier passes through impedance inverter before reaching combiner) and the peaking amplifier path comprises a peaking amplifier output for outputting an amplified second portion (Fig. 2C, see connection between output of Aux amplifier and combiner).
Claims 4-5 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Zong in view of Honda and Park as applied to claims 1 and 12, respectively, above, and further in view of Zhou et al. (Patent Publication Number US 2020/0083848 A1), hereafter referred to as Zhou.
Regarding claim 4, Zong, Honda, and Park fail to disclose:
wherein the carrier amplifier and the peaking amplifier are configured to operate as push-pull amplifiers.
However, Zhou teaches wherein the carrier amplifier and the peaking amplifier are configured to operate as push-pull amplifiers (Zhou, Paragraph 12, lines 1-2).
Zong, Honda, Park, and Zhou are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Zhou to make the amplifiers of Zong behave as push-pull amplifiers, which would have the effect of providing a well-known implementation of a differential to single-ended amplifier (Zhou, Paragraph 3, lines 1-8).
Regarding claim 5, Zong, Honda, and Park fail to disclose:
wherein the first path and the second path correspond to the push path and the pull path, respectively, of the carrier amplifier.
However, Zhou further teaches wherein the first path and the second path correspond to the push path and the pull path, respectively, of the carrier amplifier (Zhou, Paragraph 12, lines 1-2 and 4-6 [carrier amplifier Tm1/Tm2 outputs differential signal with positive/negative component, forming a push path and pull path, respectively]).
Zong, Honda, Park, and Zhou are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Zhou to make the amplifiers of Zong behave as push-pull amplifiers, which would have the effect of providing a well-known implementation of a differential to single-ended amplifier (Zhou, Paragraph 3, lines 1-8).
Regarding claim 15, Zong, Honda, and Park fail to disclose:
wherein the carrier amplifier and the peaking amplifier operate as push-pull amplifiers.
However, Zhou teaches wherein the carrier amplifier and the peaking amplifier operate as push-pull amplifiers (Zhou, Paragraph 12, lines 1-2).
Zong, Honda, Park, and Zhou are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Zhou to make the amplifiers of Zong behave as push-pull amplifiers, which would have the effect of providing a well-known implementation of a differential to single-ended amplifier (Zhou, Paragraph 3, lines 1-8).
Claims 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Zong in view of Zhou, Honda, and Park
Regarding claim 19, Zong discloses:
A power amplifier module comprising (Zong, Figs. 2C and 7A): a Doherty power amplifier (Figs. 2C and 7A), the Doherty power amplifier comprising an input (Fig. 7A, see input of Quadrature power splitter) configured to receive an input signal to be amplified (Fig. 7A, see input of Quadrature power splitter) and to split the input signal into a first portion (Fig. 7A, see connection between Quadrature power splitter and Main driver) and a second portion (Fig. 7A, see connection between Quadrature power splitter and Aux. driver), the input signal having an operating frequency (Page 6, Col. 1, Section A, lines 1-4), a carrier amplifier path coupled to the input to receive the first portion (Fig. 7A, see connection between Quadrature power splitter and Main driver), the carrier amplifier path including a carrier amplifier coupled to a differential inverter (Fig. 2C, see connection between Main amplifier and LC impedance inverter), the carrier amplifier being configured to amplify the first portion and provide an amplified first portion to the differential inverter (Fig. 2C, see connection between Main amplifier and LC impedance inverter), the capacitance coupling a first path and a second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors), a second capacitance coupling the first path and the second path of the differential inverter in parallel (Fig. 2C, see connection between outputs of Main amplifier via capacitors), and a peaking amplifier path coupled to the input to receive the second portion (Fig. 7A, see connection between Quadrature power splitter and Aux. driver) and comprising a peaking amplifier configured to amplify the second portion (Fig. 2C, see Aux amplifier), but fails to disclose a packaging substrate configured to receive a plurality of components; and [a Doherty power amplifier] implemented on the packaging substrate, the differential inverter having a capacitance configured to make the differential inverter behave as a short circuit at odd harmonics of the operating frequency and to behave as an open circuit at even harmonics of the operating frequency, the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Zhou teaches a packaging substrate configured to receive a plurality of components (Paragraph 79, lines 10-13); and [a Doherty power amplifier] implemented on the packaging substrate (see Fig. 8, see also Paragraph 79, lines 10-13), but fails to teach the differential inverter having a capacitance configured to make the differential inverter behave as a short circuit at odd harmonics of the operating frequency and to behave as an open circuit at even harmonics of the operating frequency, the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Honda teaches the differential inverter having a capacitance (Honda, Fig. 6, 3011A) configured to make the differential inverter behave as a short circuit at odd harmonics of the operating frequency (Page 8, Paragraphs 8-9) and to behave as an open circuit at even harmonics of the operating frequency (Page 8, Paragraph 9, lines 1-2), but fails to teach the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel.
However, Park teaches the second capacitance further coupling a third path and a fourth path of the peaking amplifier in parallel (Park, Fig. 3, see capacitor common to LC networks 340 and 350).
Zong, Zhou, Honda, and Park are all considered to be analogous to the claimed invention because they are in the same field of improving differential amplifiers used in radio frequency communications. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified Zong to incorporate the teachings of Zhou, Honda, and Park to modify the capacitance of Zong to include the Doherty amplifier of Zong on a packaging substrate, which would have the effect of providing a structure to contain the amplifier of Zong (Zhou, Paragraph 19, lines 10-13), to make the differential inverter of Zong behave as a short circuit at odd harmonics and an open circuit at even harmonics of the operating frequency, which would have the effect of improving the efficiency of the amplifier of Zong (Honda, Page 8, Paragraph 9), and to place the LC network of Zong in the position of the LC network of Park, which would have the effect of reducing the required circuit area (Park, Paragraph 62, lines 1-8).
Regarding claim 20, Zong further discloses:
wherein the packaging substrate comprises a semiconductor die, the capacitance and the second capacitance being implemented on-die (Zong, Page 3, Col. 1, lines 17-19).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kim et al. (Patent Publication Number US 2008/0191801) discloses (Fig. 8) a class inverse F Doherty power amplifier with harmonic termination control.
Honda et al. (Patent Publication Number US 2021/0399701) discloses (Fig. 6) a Doherty power amplifier with an output matching balun.
Beikmirza et al. (Patent Publication Number US 2024/0106396) discloses (Fig. 5) a differential push-pull Doherty amplifier with LC harmonic control.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lance T Bartol whose telephone number is (703)756-1267. The examiner can normally be reached Monday - Thursday 6:30 a.m. - 4:00 p.m. CT, Alternating Fridays 6:30 - 3:00.
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/LANCE TORBJORN BARTOL/Examiner, Art Unit 2843
/ANDREA LINDGREN BALTZELL/Supervisory Patent Examiner, Art Unit 2843
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