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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 20, 2026 has been entered.
Response to Amendment
The amendment filed February 20, 2026 has been entered. Claims 1-9, 11-14, and 16-17 remain pending in the application. Applicant’s amendments to the claims have overcome each and every rejection previously presented in the Final Office Action mailed December 23, 2025.
Response to Arguments
Applicant’s arguments, see pages 1-3, filed February 20, 2026, with respect to the rejections of claims 1-9, 11-14, and 16-17 under 35 U.S.C. § 103 have been fully considered and are persuasive. Therefore, the rejections have been withdrawn. However, upon further consideration, a new grounds of rejection is made in view of newly found prior art reference Pletcher et al. (Patent Publication Number JP 2013/501470 A), hereafter referred to as Pletcher.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 11-14 and 16 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 11 recites the limitation "and maintaining the intermediate impedance interface at a non-50 Ohm intermediate impedance" in lines 12-13. There is insufficient antecedent basis for this limitation in the claim. Removing the limitation from claim 11 is sufficient to overcome this rejection, which is how the limitation will be treated for examination purposes. Claims 12-14 and 16 are likewise rejected under this logic by virtue of their dependencies on claim 11.
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, 11, and 16-17 are rejected under 35 U.S.C. 103 as being unpatentable over Dennler et al. “Monolithic Three-Stage 6-18 GHz High Power Amplifier with Distributed Interstage in GaN Technology”, as cited by applicant, hereafter referred to as Dennler, in view of Pletcher.
Regarding claim 1, Dennler discloses:
A power amplifier (Dennler, Fig. 2) comprising: a first stage (Fig. 2, “DA”) comprising a distributed power amplifier circuitry (Page 2, Col. 1, lines 31-32); a second stage (Fig. 2, “RMA”) that is electrically operative after the first stage (Fig. 2, see connection between RMA and DA), the second stage comprising a reactively matched power amplifier circuitry (Page 2, Col. 1, lines 32-33); an intermediate impedance interface between the first stage and the second stage (Fig. 2, see Real impedance between DA and RMA); and a periphery ratio of the second stage to the first stage that is less than or equal to 2:1 (periphery ratio is approximately 1.29:1, see Page 3, Col. 1, lines 1-3 and 19-22), but fails to disclose wherein the intermediate impedance interface is a real non-50 Ohm impedance selected to be 28 Ohm or 30 Ohm and is implemented through a wideband impedance matching practice comprising a series of transmission lines, shunt transmission line stubs, shunt shorted metal-insulator-metal (“MIM”) capacitors, and series MIM capacitors.
However, Pletcher teaches wherein the intermediate impedance interface is a real non-50 Ohm impedance (Pletcher, Fig. 5A, 330) selected to be 28 Ohm or 30 Ohm (Page 5, Paragraph 7, lines 5-8), but fails to teach and is implemented through a wideband impedance matching practice comprising a series of transmission lines, shunt transmission line stubs, shunt shorted metal-insulator-metal (“MIM”) capacitors, and series MIM capacitors.
However, Bouisse teaches and is implemented through a wideband impedance matching practice (Bouisse, Fig. 1, 5) comprising a series of transmission lines, shunt transmission line stubs, shunt shorted metal-insulator-metal (“MIM”) capacitors, and series MIM capacitors (Page 11, Paragraph 2, lines 1-4).
Dennler, Pletcher, and Bouisse are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Pletcher and Bouisse to include a 30 Ohm intermediate impedance, which would have the effect of achieving appropriate impedance matching for the circuit of Dennler (Pletcher, Page 5, Paragraph 2, lines 5-9), and to include transmission lines and MIM capacitors in the intermediate impedance of Dennler, which would have the effect of increasing the stability of the circuit of Dennler (Bouisse, Page 3, 2nd Paragraph from bottom, lines 1-3).
Regarding claim 2, Dennler further discloses:
wherein the first stage comprises at least two unit cells in the distributed power amplifier circuitry (Dennler, Page 3, Col. 1, lines 19-22).
Regarding claim 3, Dennler further discloses:
wherein the second stage comprises at least two unit cells in the reactively matched power amplifier circuitry (Dennler, Page 3, Col. 1, lines 1-3).
Regarding claim 11, Dennler discloses:
A method for a power amplifier (Dennler, Fig. 2), the method comprising: transmitting a signal to be amplified to a first stage of a power amplifier (Fig. 2, “DA”), wherein the first stage includes distributed power amplifier circuitry (Page 2, Col. 1, lines 31-32); amplifying the signal in the first stage (Fig. 2, see signal path through DA); transmitting the signal to a second stage (Fig. 2, see connection between DA and RMA) through an intermediate impedance interface between the first stage and the second stage (Fig. 2, see Real impedance between DA and RMA), wherein the second stage includes reactively matched power amplifier circuitry (Fig. 2, “RMA”; amplifying the signal in the second stage (Fig. 2, see signal path through RMA); but fails to disclose maintaining the intermediate impedance interface at a real, non-50 Ohm impedance between 28 Ohm and 30 Ohm implemented by a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors, and series MIM capacitors; and maintaining the intermediate impedance interface at a non-50 Ohm intermediate impedance.
However, Pletcher teaches maintaining the intermediate impedance interface at a real, non-50 Ohm impedance (Pletcher, Fig. 5A, 330) between 28 Ohm and 30 Ohm (Page 5, Paragraph 7, lines 5-8) and maintaining the intermediate impedance interface at a non-50 Ohm intermediate impedance (Pletcher, Fig. 5A, 330), but fails to teach [the impedance] implemented by a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors, and series MIM capacitors.
However, Bouisse teaches [the impedance] implemented by a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors, and series MIM capacitors (Bouisse, Page 11, Paragraph 2, lines 1-4).
Dennler, Pletcher, and Bouisse are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Pletcher and Bouisse to include a 30 Ohm intermediate impedance, which would have the effect of achieving appropriate impedance matching for the circuit of Dennler (Pletcher, Page 5, Paragraph 2, lines 5-9), and to include transmission lines and MIM capacitors in the intermediate impedance of Dennler, which would have the effect of increasing the stability of the circuit of Dennler (Bouisse, Page 3, 2nd Paragraph from bottom, lines 1-3).
Regarding claim 16, Dennler further discloses:
further comprising: matching at least one real impedance from an output impedance of the first stage (Dennler, Fig. 2, see real impedance at output of DA) with at least one complex impedance of an input impedance of the second stage (Fig. 2, see that RMA is a reactively-matched amplifier, and therefore has a complex impedance) that is adapted to improve bandwidth compared to matching two complex impedances (Page 3, Section V. Conclusion, lines 2-6).
Regarding claim 17, Dennler discloses:
A power amplifier (Dennler, Fig. 2) comprising: a distributed power amplifier stage (Fig. 2, “DA”, see also Page 2, Col. 1, lines 31-32); a reactively matched power amplifier stage (Fig. 2, “RMA”, see also Page 2, Col. 1, lines 32-33) that is electrically coupled to the distributed power amplifier stage (Fig. 2, see connection between RMA and DA); and an intermediate impedance interface between the distributed power amplifier stage and the reactively matched power amplifier stage (Fig. 2, see Real impedance between DA and RMA); wherein there is a periphery ratio that is less than or equal to 2:1 between the distributed power amplifier stage and the reactively matched power amplifier stage (periphery ratio is approximately 1.29:1, see Page 3, Col. 1, lines 1-3 and 19-22), but fails to disclose wherein the intermediate impedance interface is a real non-50 Ohm impedance selected to be 28 Ohm or 30 Ohm and is implemented through a wideband impedance matching practice comprising a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors and series MIM capacitors.
However, Pletcher teaches wherein the intermediate impedance interface is a real non-50 Ohm impedance (Pletcher, Fig. 5A, 330) selected to be 28 Ohm or 30 Ohm (Page 5, Paragraph 7, lines 5-8), but fails to teach and is implemented through a wideband impedance matching practice comprising a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors and series MIM capacitors.
However, Bouisse teaches and is implemented through a wideband impedance matching practice (Bouisse, Fig. 1, 5) comprising a series of transmission lines, shunt transmission line stubs, shunt shorted MIM capacitors and series MIM capacitors (Page 11, Paragraph 2, lines 1-4).
Dennler, Pletcher, and Bouisse are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Pletcher and Bouisse to include a 30 Ohm intermediate impedance, which would have the effect of achieving appropriate impedance matching for the circuit of Dennler (Pletcher, Page 5, Paragraph 2, lines 5-9), and to include transmission lines and MIM capacitors in the intermediate impedance of Dennler, which would have the effect of increasing the stability of the circuit of Dennler (Bouisse, Page 3, 2nd Paragraph from bottom, lines 1-3).
Claims 4-8 and 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Dennler in view of Pletcher and Bouisse as applied to claims 1 and 11, respectively, above, and further in view of Du et al. (Patent Number CN 215,990,715 U), hereafter referred to as Du.
Regarding claim 4, Dennler fails to disclose:
further comprising: a third stage that is electrically operative after the second stage, the third stage comprising another reactively matched power amplifier circuitry.
However, Du teaches further comprising: a third stage (Du, Fig. 4, see transistors in parallel with HEMT3) that is electrically operative after the second stage (Fig. 4, see connection between transistors in parallel with HEMT3 [third stage] and transistors in parallel with HEMT2 [second stage]), the third stage comprising another reactively matched power amplifier circuitry (Fig. 4, see reactive matching circuit 303 coupled to transistors in parallel with HEMT3).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 5, Dennler fails to disclose:
wherein a periphery ratio of the first stage to the second stage to the third stage increases from the first stage to the second stage to the third stage.
However, Du further teaches wherein a periphery ratio of the first stage to the second stage to the third stage increases from the first stage to the second stage to the third stage (Du, Page 6, Paragraph 3, lines 2-6 [periphery ratio is 1:2:4]).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 6, Dennler further discloses:
wherein the periphery ratio of the first stage to the second stage is 1.5:2 (periphery ratio is approximately 1.55:2, see Page 3, Col. 1, lines 1-3 and 19-22), but fails to disclose [wherein the periphery ratio of the second stage] to the third stage is 2:4.
However, Du further teaches [wherein the periphery ratio of the second stage to the third stage] is 2:4 (Du, Page 6, Paragraph 3, lines 2-6 [periphery ratio is 2:4]).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 7, Dennler fails to disclose:
wherein the third stage comprises at least two unit cells in the another reactively matched power amplifier circuitry.
However, Du further teaches wherein the third stage comprises at least two unit cells in the another reactively matched power amplifier circuitry (Du, Page 6, Paragraph 3, lines 5-6).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 8, Dennler fails to disclose:
further comprising: an operative bandwidth of the power amplifier that ranges from 28-40Ghz.
However, Du further teaches further comprising: an operative bandwidth of the power amplifier that ranges from 28-40Ghz (Du, Page 1, Section “Technical Field”, Paragraph 1, lines 1-2).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to configure the amplifier of Dennler to have an operative bandwidth from 28-40 GHz, which would have the effect of enabling the amplifier of Dennler to work in communications systems using the Ka frequency band (Du, Page 1, Section “Background”, Paragraph 1, lines 1-4).
Regarding claim 12, Dennler fails to disclose:
further comprising: transmitting the signal to a third stage that is electrically operative after the second stage, wherein the third stage includes reactively matched power amplifier circuitry; and amplifying the signal in the third stage.
However, Du teaches further comprising: transmitting the signal to a third stage (Du, Fig. 4, see transistors in parallel with HEMT3) that is electrically operative after the second stage (Fig. 4, see connection between transistors in parallel with HEMT3 [third stage] and transistors in parallel with HEMT2 [second stage]), wherein the third stage includes reactively matched power amplifier circuitry (Fig. 4, see reactive matching circuit 303 coupled to transistors in parallel with HEMT3); and amplifying the signal in the third stage (Fig. 4, see signal path through transistors in parallel with HEMT3).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 13, Dennler fails to disclose:
wherein the periphery ratio of the first stage to the second stage to the third stage increases from the first stage to the second stage to the third stage.
However, Du further teaches wherein the periphery ratio of the first stage to the second stage to the third stage increases from the first stage to the second stage to the third stage (Du, Page 6, Paragraph 3, lines 2-6 [periphery ratio is 1:2:4]).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Regarding claim 14, Dennler further discloses:
wherein the periphery ratio of the first stage to the second stage is 1.5:2 (periphery ratio is approximately 1.55:2, see Page 3, Col. 1, lines 1-3 and 19-22), but fails to disclose [wherein the periphery ratio of the second stage] to the third stage is 2:4.
However, Du further teaches [wherein the periphery ratio of the second stage to the third stage] is 2:4 (Du, Page 6, Paragraph 3, lines 2-6 [periphery ratio is 2:4]).
Dennler, Pletcher, Bouisse, and Du are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Du to include the third stage of Du in the amplifier of Dennler, which would have the effect of providing additional amplifying stages to increase the gain of the amplifier of Dennler.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Dennler in view of Pletcher and Bouisse as applied to claim 1 above, and further in view of Barton et al. (Patent Publication Number US 2015/0365052 A1), hereafter referred to as Barton.
Regarding claim 9, Dennler further discloses:
further comprising: an input of the power amplifier (Dennler, Fig. 2, RFin), wherein the input is electrically operative before the first stage (Fig. 2, see connection between RFin and DA); and a second hybrid coupler (Fig. 2, “Combiner”) coupled to an output of the power amplifier (Fig. 2, see connection between Combiner and RFout), wherein the output is electrically operative after the second stage (Fig. 2, see connection between RFout and RMA), but fails to disclose a first hybrid coupler coupled to [the input of the power amplifier].
However, Barton teaches a first hybrid coupler (Barton, Fig. 55, see input transmission lines ZT, Z2, and Z1) coupled to [the input of the power amplifier] (Fig. 55, see connection between input transmission lines ZT, Z2, Z1, and power amplifiers 120).
Dennler, Pletcher, Bouisse, and Barton are all considered to be analogous to the claimed invention because they are in the same field of improving power 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 Dennler to incorporate the teachings of Barton to include an input hybrid coupler in the amplifier of Dennler, which would have the effect of splitting the input signal of Dennler into multiple circuit paths.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kamioka et al. “Over 20 W 2.5 to 10.5 GHz wideband two-stage GaN MMIC power amplifier with distributed and reactively-matched stages” discloses (Fig. 1) a power amplifier comprising distributed and reactively-matched stages.
Fujii et al. “Single supply 1W Ku-band Power Amplifier Based on 0.25μm E-mode PHEMT” discloses (Fig. 5) a three stage reactively-matched power amplifier.
Kobayashi (Patent Publication Number US 2013/0063213 A1) discloses (Fig. 1) a two-stage distributed power amplifier with a non-50 ohm intermediate impedance interface.
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.
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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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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/LANCE TORBJORN BARTOL/Examiner, Art Unit 2843
/ANDREA LINDGREN BALTZELL/Supervisory Patent Examiner, Art Unit 2843
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