DETAILED ACTION
Response to Arguments
Applicant's arguments filed on 7/6/2026 have been fully considered but they are not persuasive.
1). Applicant’s argument – The beam-forming circuit in Nagaraj, however, forms a beam in a direction corresponding to an input beam weight set. Moreover, the beam-forming circuit is not the Butler matrix as recited in the amended claims. The Butler matrix recited in the amended claims is capable of outputting RF signals with the same amplitude and linearly inclined phases from all output ports when an RF signal is input to a certain input port of the Butler matrix. See, Paragraph [0056]. The inclination of a phase differs depending on the input port of the Butler matrix. Thus, beamforming is made possible by equipping each output port of the Butler matrix with a different antenna. Furthermore, the pending claims enable beam switching by switching the input port through which the RF signal is fed into the Butler matrix.
Examiner’s response – First, it is commonly known that is a beamforming network used to feed a phased array of antenna elements. Its purpose is to control the direction of a beam, or beams, of radio transmission. By routing radio frequency (RF) signals through fixed hybrid couplers and phase shifters, it controls antenna beam direction electronically without mechanical movement. Nagaraj et al discloses “The beamformer circuit 318 can be configured to receive and process an RF communications signal 320 based on the beam weights w(1,1)-w(M,N) in each of the beam weight sets Ws1-WsK to generate a plurality of weighted RF communications signals 322(1,1)-322(M,N). The radiating elements 310(1,1)-310(M,N) in the antenna array 308 are configured to radiate the weighted RF communications signals 322(1,1)-322(M,N) simultaneously to form a respective RF beam among the RF beams 312(1)-312(K) that corresponds to a respective beam weight set among the beam weight sets W.sub.s1-W.sub.sK. In this regard, the beamformer circuit 318 is configured to generate a total of ‘K’ sets of the weighted RF communications signals 322(1,1)-322(M,N) for forming and/or modifying the RF beams 312(1)-312(K), respectively” ([0045]); and “Each beam weight in a given beam weight set is a complex weight consisting of a respective phase term and a respective amplitude term. The phase terms in the complex beam weight can be determined to cause the multiple simultaneously radiated RF signals to constructively combine in one direction to form the RF beams 200, while destructively averaging out in other directions” ([0028]); that is, the beamformer circuit 318 performs the similar function of a Butler matrix, and the beamformer circuit 318 can be viewed as a type of Butler matrix.
Second, in response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., “capable of outputting RF signals with the same amplitude” and “enable beam switching by switching the input port through which the RF signal is fed into the Butler matrix”) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Third, the newly cited reference, Hormis et al (US 2021/0099215), discloses that a Butler matrix (404 in Figure 4) can be used as a beamformer for generating a spatial beam. And another prior art, Li et al (US 2007/0140177), discloses that a Butler matrix (440 in Figure 4A) can be implemented between optical transceiver (434/436/438) and antenna (460). Therefore, the combination of Ito et al and Nagaraj et al and Hormis et al and Li et al teaches/suggests that the beamforming circuit can be a Butler matrix.
Claim Rejections - 35 USC § 103
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 1-2 are rejected under 35 U.S.C. 103 as being unpatentable over Ito et al (WO 2020/121919; published on 6/18/2020. The corresponding English translation of WO 2020/121919 is US 2022/0109518. Hereinafter, the cited paragraphs etc. in this Office Action are for US 2022/0109518) in view of Nagaraj et al (US 2021/0336681) and Hormis et al (US 2021/0099215) and Li et al (US 2007/0140177).
1). With regard to claim 1, Ito et al discloses a wireless communication method in a wireless communication system (Figure 1-4 etc.) including an accommodation station device (10 or 10a in Figures 1-2, or 910 in Figure 3) and a base station device (30 in Figures 1-2, or 930 in Figure 3) that performs beam formation ([0004]-[0005], [0031]-[0032] and [0052]-[0056] etc.) according to control of the accommodation station device (e.g., [0005], “by controlling a wavelength of an optical carrier using the fact that a delay difference is generated between optical signals of respective wavelengths due to wavelength dispersion during optical fiber transmission”; or, Figures 1-2, “phase adjustment”), the wireless communication method comprising:
transmitting an optical modulation signal (Figures 1-4, optical modulation signal is transmitted from Accommodation Station to Base Station) generated by performing intensity modulation ([0003], “an accommodation station (master station) modulates intensity of an optical carrier with a radio frequency (RF) signal to be transmitted”) on an optical signal (from light source 11, or 41-1 to 41-n; or Figure 3, from a multi-wavelength variable light source 911) on the basis of a transmission signal (“RF Signal”) to be transmitted to the base station device via an optical transmission line (20 or 920) by the accommodation station device controlling any combination of a light wavelength, a frequency, or an optical polarized wave, or a plurality of frequencies or a plurality of light wavelengths (Figure 3, [0005]-[0006], “by controlling a wavelength of an optical carrier using the fact that a delay difference is generated between optical signals of respective wavelengths due to wavelength dispersion during optical fiber transmission (see, for example, PTL1. FIG. 3 is a block diagram of an RoF system 900 to which the technique of PTL1 is applied. A multi-wavelength variable light source 911 of an accommodation station 910 outputs a plurality of optical signals. A wavelength interval between these optical signals can optionally be changed. An optical modulator 912 modulates an optical signal of each wavelength with a RF signal to be transmitted. In this way, the optical modulator 912 outputs the plurality of optical modulated signals”), to perform beamforming control of the base station device ([0005]-[0007]);
transmitting the optical modulation signal (Figure 1-3 etc., the optical modulation signal is transmitted from Accommodation Station to Base Station),
inputting, by the base station device (30 in Figures 1-2, or 900 in Figure 3), an electrical signal (the electrical signal generated by O/E 32-1 to 32-n; or 932-1 to 932-n in Figure 3) based on the optical modulation signal to a beamforming circuit (the circuit after the O/E combined with the antenna elements 33-i or 933-i) having a plurality of input ports (the plurality ports for the plurality of antenna) to perform beam formation in a direction corresponding to an input port to which the electrical signal is input ([0004]-[0005], [0031]-[0032] and [0052]-[0056] etc.).
In Figure 3 etc., Ito et al does not expressly show that the optical modulation signal is transmitted after dispersion compensation is performed in an electrical domain or an optical domain in the accommodation station device or performing dispersion compensation on the optical modulation signal on the optical transmission line; and the electrical signal is first input to a beamforming circuit having a plurality of input ports, wherein the beamforming circuit is a Butler matrix.
Regarding the dispersion compensation, in Figure 4, Ito et al discloses that a dispersion compensation can be performed on the optical modulation signal on the optical transmission line (by the PDM 953, [0008], “Each optical modulated signal is sent to a programmable dispersion matrix (PDM) 953”). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a dispersion compensation unit as taught by Figure 4 of Ito et al into Figure 3 of Ito et al so that the phase difference of the different wavelengths can be further adjusted and more accurately controlled, and the functions and controlling of the direction of the beamforming are enhanced.
Regarding the beamforming circuit, in Figure 3 etc., Ito et al does expressly show a specific beamforming circuit, however, as discussed above, the component/circuit after the O/E as well as the antenna elements 33-i or 933-I actually form a beamforming circuit so that “forming directivity” is realized. Another prior art, Nagaraj et al, discloses a radio-over-fiber (wireless communications) system/method (Figure 3 etc.), in which the base station (300) receives optical modulation signals, and electrical signals are obtained by E/O converters ([0055] and [0058]), and then electrical signals are input to a beamforming circuit (318), which further processes the RF electrical signals and output a plurality of electrical signals to the antenna array (308). Also, as shown in Figure 3 of Ito, a plurality of electrical signals output from the plurality of O/Es are sent to the individual antenna of the antenna array (933) respectively, then it is obvious to one skilled in the art that the plurality of electrical signals also can be sent to a plurality of input ports of a beamforming circuit so to process the plurality of input electrical signals respectively.
Nagaraj et al does not expressly call the beamforming circuit (318) a Butler matrix. However, first, as disclosed in paragraphs [0028] and [0045], Nagaraj et al discloses that the beam weight consists of phase term and amplitude term; and the beamformer circuit 318 receives and processes an RF communications signal 320 based on the beam weights, so to cause the multiple simultaneously radiated RF signals to constructively combine in one direction to form the RF beams; therefore, performs the similar function of a Butler matrix, and the beamformer circuit 318 can be viewed as a type of Butler matrix. Second, to use a Butler matrix for beamforming is well known in the art, e.g., Hormis et al (US 2021/0099215), discloses that a Butler matrix (404 in Figure 4) can be used as a beamformer for generating a spatial beam and “transmission/reception is essentially beamformed in a particular spatial direction referred to as a directional beam” ([0025]). And another prior art, Li et al (US 2007/0140177), discloses a radio over fiber system/method (Figure 4A etc.), and a Butler matrix (440 in Figure 4A) can be implemented between optical transceivers (434/436/438) and antenna (460). Therefore, the combination of Ito et al and Nagaraj et al and Hormis et al and Li et al teaches/suggests that a Butler matrix can be used as a beamforming circuit.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a beamforming circuit or Butler matrix as taught by Nagaraj et al and Hormis et al and Li et al to the system/method of Ito et al so that the electrical signal can be further processed by a beamforming circuit, and “forming directivity” can more accurately controlled.
2). With regard to claim 2, Ito et al and Nagaraj et al and Hormis et al and Li et al disclose all of the subject matter as applied to claim 1 above. And the combination of Ito et al and Nagaraj et al and Hormis et al and Li et al further discloses wherein the accommodation station device controls the light wavelength (Ito: Figure 3, [0005]-[0006], “by controlling a wavelength of an optical carrier using the fact that a delay difference is generated between optical signals of respective wavelengths due to wavelength dispersion during optical fiber transmission (see, for example, PTL1). FIG. 3 is a block diagram of an RoF system 900 to which the technique of PTL1 is applied. A multi-wavelength variable light source 911 of an accommodation station 910 outputs a plurality of optical signals. A wavelength interval between these optical signals can optionally be changed. An optical modulator 912 modulates an optical signal of each wavelength with a RF signal to be transmitted. In this way, the optical modulator 912 outputs the plurality of optical modulated signals”) to transmit the optical modulation signal generated by performing intensity modulation on an optical signal (Ito: from the Multi-Wavelength Variable Light Source 911) having the controlled light wavelength on the basis of the transmission signal to the base station device to control beamforming control of the base station device (Ito: [0004]-[0010]), and the base station device demultiplexes the chromatic dispersion-compensated optical modulation signal depending on wavelengths (Ito: by the Optical Demultiplexer 931 in Figure 3), converts demultiplexed signals into electrical signals (Ito: by O/E 932-i), and then inputs the electrical signals to the beamforming circuit in phase to perform beam formation (as discussed in claim 1 rejection, the combination of Ito et al and Nagaraj et al teaches/suggests a beamforming circuit; and the “phase” is controlled by adjusting the wavelengths and the programmable dispersion matrix (PDM) 953, and the beamforming circuit).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Ito et al and Nagaraj et al and Hormis et al and Li et al as applied to claim 1 above, and further in view of Seto et al (US 2006/0079290).
Ito et al and Nagaraj et al and Hormis et al and Li et al disclose all of the subject matter as applied to claim 1 above. And the combination of Ito et al and Nagaraj et al and Hormis et al and Li et al further discloses wherein the accommodation station device controls the light wavelength to transmit the optical modulation signal generated by performing intensity modulation on an optical signal on the basis of the transmission signal having the converted frequency to the base station device to perform beamforming control of the base station device, and the base station device converts the chromatic dispersion-compensated optical modulation signal into an electrical signal and then demultiplexes the optical signal depending on wavelengthes to input electrical signals to the beamforming circuit in phase to perform beam formation (refer to the claims 1-2 rejections above).
But, Ito et al and Nagaraj et al and Hormis et al and Li et al do not expressly disclose wherein the accommodation station device controls the frequency to convert a frequency of the transmission signal and transmits the optical modulation signal generated by performing intensity modulation on an optical signal on the basis of the transmission signal having the converted frequency to the base station device to perform beamforming control of the base station device, and the base station device converts the chromatic dispersion-compensated optical modulation signal into an electrical signal and then demultiplexes the electrical signal depending on frequencies to input electrical signals to the beamforming circuit in phase to perform beam formation.
However, Seto et al discloses a radio-over-fiber communication system/method (Figures 34 and 40-43), which has an accommodation station device (Control Station 2) and base station device (Base Station 1), and the accommodation station device controls the frequency to convert a frequency of the transmission signal (by the frequency converter 204 a-204c) and transmits the optical modulation signal (output from the E/O converter 47) generated by performing intensity modulation ([0315] etc.) on an optical signal (the optical signal sent to the E/O converter 47) on the basis of the transmission signal having the converted frequency (from the sub-carrier multiplexing signal generation means 46) to the base station device (Base Station 1) to perform beamforming control of the base station device ([0050], “a control station provided with a beam forming network for deriving a desired signal from a received signal of said variable directional array antenna”, and Abstract), and the base station device converts the optical modulation signal into an electrical signal (by the O/E converter 31) and then demultiplexes the electrical signal depending on frequencies to input electrical signals (by an distributor/divider 32, [0356], “divider 32 for dividing the output signal of the optical/electric converter 31 to plural signals with different frequency, frequency converters 202a to 202c for converting the respective frequency signals divided by the divider 32 to radio frequency signals”) to a beamforming circuit (formed by components 35a-c/161a-c/36a-c. Also refer the beam forming network 121 in Figure 26 etc., [0302]) in phase to perform beam formation (“phase” is controlled by the weighting coefficient calculation circuit 165, the multipliers 43a to 43c and frequency converter 204 etc., and [0287]-[0288] etc.). In Figure 34, Seto et al does not show a chromatic dispersion-compensation module, however, Ito et al discloses that the transmitted optical signal can be chromatic dispersion-compensated; therefore, the combination of Nagaraj et al and Ito et al and Seto et al teaches/suggests to convert a chromatic dispersion-compensated optical modulation signal into an electrical signal and then demultiplex the electrical signal depending on frequencies to input electrical signals to the beamforming circuit by in phase to perform beam formation.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply the teachings of Seto et al to the system/method of Ito et al and Nagaraj et al and Hormis et al and Li et al so that the phases of the different signal components can be controlled by varying the frequencies of the frequencies of the transmission signals, and the forming directivity can be conveniently controlled.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Ito et al and Nagaraj et al and Hormis et al and Li et al as applied to claim 1 above, and further in view of Seto et al (US 2006/0079290) and Haraguchi et al (US 20220094459).
Ito et al and Nagaraj et al and Hormis et al and Li et al disclose all of the subject matter as applied to claim 1 above. And the combination of Ito et al and Nagaraj et al and Hormis et al and Li et al teaches/suggests wherein the base station device (e.g., Li: 420 in Figure 4A; the transceiver TRX 434/436/438) converts a radio signal (received by the antenna 460) transmitted from an external device (the external device that transmits RF signals, and the RF signals are received by the antenna via the beams 226 or 224 or 222) into an electrical signal (by the antenna and Butler array), inputs the electrical signal to an output port (the port of Butler Array 440, which connected to the radio frequency links 450) of the beamforming circuit, outputs the electrical signal from the input port (the port connected to the TRX0 – TRX2) of the beamforming circuit corresponding to the output port ([0103]).
Ito et al and Nagaraj et al and Hormis et al and Li et al do not expressly disclose that the base station device transmits an optical signal obtained by intensity modulation using the electrical signal to the accommodation station device, dispersion compensation is performed in an electrical domain or an optical domain in the accommodation station device, or the dispersion compensation is performed on the optical modulation signal on the optical transmission line, and the accommodation station device demodulates the optical signal transmitted from the base station device.
However, as disclosed by Li, the signal transmission between an accommodation station device and a base station device is can be bi-directional. And, Seto et al discloses a radio-over-fiber communication system/method (Figures 1, 8, 16, 26 and 34 etc.), which has an accommodation station device (Control Station 2) and base station device (Base Station 1), wherein the base station device converts a radio signal transmitted from an external device (the device that sends the RF signal to the antenna) into an electrical signal (e.g., by the antenna 4-1 in Figure 1, or by antenna 4a-4d in Figure 16), inputs the electrical signal to an output port (the port sends/receives electrical signal to/from the antenna 4-i in Figure 1, or 4a-4n in Figure 26) of the beamforming circuit (e.g., the element antenna drives 56-1 to 56-n form a beamforming circuit; also refer to Figure 16, the Beam Forming Network 121) outputs the electrical signal from the input port (the ports connected to E/O 9 in Figure 1; or the ports connected to the circulators 36a – 36d in Figure 26) of the beamforming circuit corresponding to the output port (the port accepts electrical signal from the antenna), and transmits an optical signal (Figure 1, output from E/O 9 in Figure 1; or Figure 26, output from E/O 10) obtained by intensity modulation (by E/O 9 in Figure 1; or E/O 10 in Figure 26) using the electrical signal to the accommodation station device (Control station 2), phase (by components 60-1 to 60-n) and amplitude adjustment (by components 60-1 to 60-n) is performed in an electrical domain in the accommodation station device, and the accommodation station device demodulates the optical signal transmitted from the base station device (Figure 1, Demodulator 26; Figure 26, Demodulator 19). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply the teachings of Seto et al to the system/method of Ito et al and Nagaraj et al so that a bidirectional wireless communication system/method can be obtained.
Seto et al does not expressly disclose that dispersion compensation is performed. However, to perform a dispersion compensation in an electrical domain or an optical domain in the accommodation station device is a common practice in the art. E.g., Haraguchi et al discloses an optical control type phased array antenna (Figures 1, 4-6 and 8), in which a dispersion compensation is performed in an optical domain in the accommodation station device (by the Optical Dispersion Compensator 411 to 41M in optical dispersion compensation circuit 40 in Figure 1; or 40A in Figures 4-6 and 8). Haraguchi et al teaches “an optical dispersion compensation circuit for compensating for a phase difference between the plurality of modulated optical signals by performing dispersion compensation on the reception optical signals” (Abstract, and Figures 2 and 7). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to apply a dispersion compensation in the accommodation station device as taught by Haraguchi et al to the system/method of Ito et al and Nagaraj et al and Seto et al so that the phase difference between the plurality of modulated optical signals can be controlled by the dispersion compensator, and the received signal can be better demodulated.
Allowable Subject Matter
Claim 4 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 9 is allowed.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 2022/0167241
US 2020/0028556
US 2020/0112378
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.
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/LI LIU/Primary Examiner, Art Unit 2634
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