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 .
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph:
An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: to receive . . . to calculate . . . and to estimate . . . in claim 1.
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1, 2, and 6-20 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Tamma et al. (US 2022/0330180 A1), hereinafter referred to as D1.
Regarding claims 1, , D1 discloses a method, circuit, and system of highly accurate carrier frequency offset estimation, which comprises:
to receive a radio signal comprising a data packet, said data packet comprising a first portion comprising an encoded bit sequence and including information specific to the data packet and a second portion comprising an encoded bit sequence and comprising corresponding information specific to the data packet (Referring to Figure 1, packaging a protocol packet (transmitted and received) to include a predetermined bit sequence with a specified prefix (first portion comprising an encoded bit sequence and including information specific to the data packet and a second portion comprising an encoded bit sequence and comprising corresponding information specific to the data packet), one or more signature elements, and a specified suffix at a possibly known or negotiated location in the protocol packet. The predetermined bit sequence includes an m-bit prefix, one or more copies of an L-bit signature segment, and an m-bit suffix, where the m-bit prefix is identical to the last m-bits of the L-bit signature segment and where the m-bit suffix is identical to the first m-bits of the L-bit signature segment. The predetermined bit sequence includes a single signature segment, the m-bit prefix and m-bit suffix may be predetermined values known to the transmitting and receiving devices without any relationship to the signature segment. See paragraph 0020.);
to calculate a correlation metric using the first portion and the second portion (Referring to Figure 1, When triggered in alignment with a signature segment, the CFOF sequence detector will take the samples corresponding to a segment and correlate them against the reference signal (calculate a correlation metric). See paragraph 0034.); and
to estimate a carrier frequency offset between the radio signal and the radio receiver device using the correlation metric (Referring to Figure 1, the predetermined bit sequence may be formatted as a CFO fingerprinting (CFOF) sequence which may be detected in the physical layer's PDU to produce an accurate CFO estimate according to the sequence and correlation. See paragraphs 0020 and 0034.)
Regarding claim 2, D1 discloses wherein the first portion includes information identifying a data rate and/or a length of one or more portions of the data packet (Referring to Figures 1, 5, and 8, Upon receiving the configuration packet, the receiving wireless device 24 is configured with the sequence parameters which specify the length and content of the CFOF sequence 28A-C, including the prefix portion 28A, one or more signature elements 28B, and a suffix portion 28C. See paragraphs 0027-0029.)
Regarding claim 6, D1 discloses wherein calculating the correlation metric between the first portion and the second portion comprises performing a correlation operation such as a cross correlation (Referring to Figures 1, 5, and 8, the specific structural requirements for the CFOF sequence 28 govern the choice of the bit patterns used for the prefix, suffix and signature segments to provide high estimation accuracy, regardless of the auto-correlation and cross-correlation properties of the signature segments 28B. See paragraph 0027.)
Regarding claim 7, D1 discloses wherein the second portion is not a repetition of the first portion and wherein calculating the correlation metric comprises performing one or more initial processing steps to one or both of the first and second portions prior to performing the correlation operation (Referring to Figures 1, 5, and 8, packaging a protocol packet to include a predetermined bit sequence with a specified prefix, one or more signature elements, and a specified suffix at a possibly known or negotiated location in the protocol packet (first and second portion, which are not a repetition). In selected embodiments, the predetermined bit sequence includes an m-bit prefix, one or more copies of an L-bit signature segment, and an m-bit suffix, where the m-bit prefix is identical to the last m-bits of the L-bit signature segment and where the m-bit suffix is identical to the first m-bits of the L-bit signature segment. In other embodiments where the predetermined bit sequence includes a single signature segment, the m-bit prefix and m-bit suffix may be predetermined values known to the transmitting and receiving devices without any relationship to the signature segment. By transmitting the predetermined bit sequence in the protocol packet, a receiving device is configured to accurately measure a carrier frequency offset value from the signature element(s) in the detected predetermined bit sequence using, thereby reducing the measurement time and power consumption required to estimate the CFO. When used with BLE, ANT and other similar narrowband wireless protocols employing continuous-phase frequency modulation techniques (e.g., GFSK, FSK, IEEE 802.15.4g O-QPSK PHY, etc.), the predetermined bit sequence may be formatted as a CFO fingerprinting (CFOF) sequence (initial processing steps) which may be detected in the physical layer's PDU to produce an accurate CFO estimate that is very useful in localization applications (such as distance estimation using Round-Trip Time (RTT) measurements or phase-based techniques) and/or direction-finding techniques (such as angle-of-arrival/angle-of departure). An accurate CFO measurement can be also used as a metric for authenticating communication with a known peer device using an RF fingerprinting technique. The disclosed CFO estimation method and apparatus for embedding a known CFOF sequence in the PDU is designed to cause minimal disruption to the protocol procedure and provides a level of accuracy that is much higher than what is afforded by typical packet synchronization techniques using the Start-of-Frame Delimiter (SFD) or Access Address (in BLE). In addition, the disclosed CFOF sequence provides for a flexible accuracy level by increasing the number of signature segments in each CFOF sequence (for higher accuracy) or decreasing the number of signature segments in each CFOF sequence (for lower accuracy). See paragraphs 0020-0022.)
Regarding claim 8, D1 discloses wherein the first and second portions comprise information spread differently over a plurality of frequency bands, and calculating the correlation metric comprises reordering frequency bands of the first and/or second portions (Referring to Figures 8-12, the CFOF pre-processor 500 is connected to receive input narrowband phase samples 501 generated upon reception of the CFO measurement packet. The input narrowband phase samples 501 are differentiated by the phase discriminator 502 to produce instantaneous frequencies 503 (information spread differently over a plurality of frequency bands), and then integrated by the integrator 504 to calculate a phase change over each symbol duration 505. For example, when the sampling rate is 4 times the modulated symbols rate, the integrator 504 may use a sliding window of 4 samples to integrate each group of 4 consecutive instantaneous frequency input values 503 to calculate the corresponding phase change over one symbol duration 505. In an optional step, a multiplier 507 scales the phase values by a constant equal to 1/(2h), where h is the modulation index. The scaling step is designed to accommodate large modulation indexes. The output from the multiplier 507 is passed to a buffer 508, such as a 128-tap FIFO, and the buffer 508 output gets passed to the signature detector 509 (calculating the correlation metric comprises reordering frequency bands of the first and/or second portions). See paragraphs 0064-0066.)
Regarding claim 9, D1 discloses wherein the second portion uses a different modulation scheme to the first portion, and calculating the correlation metric comprises converting the modulation of the first and/or second portion (Referring to Figures 11-13, a CFOF pre-processor 500 which converts the input I/Q samples into phase values under control of the CFOF controller so as to be selectively enabled only when the CFOF sequence is in the input narrowband phase samples. As depicted, the CFOF pre-processor 500 is connected to receive input narrowband phase samples 501 generated upon reception of the CFO measurement packet. The input narrowband phase samples 501 are differentiated by the phase discriminator 502 to produce instantaneous frequencies 503, and then integrated by the integrator 504 to calculate a phase change over each symbol duration 505. For example, when the sampling rate is 4 times the modulated symbols rate, the integrator 504 may use a sliding window of 4 samples to integrate each group of 4 consecutive instantaneous frequency input values 503 to calculate the corresponding phase change over one symbol duration 505. In an optional step, a multiplier 507 scales the phase values by a constant equal to 1/(2h), where h is the modulation index (different modulation scheme to the first portion). The scaling step is designed to accommodate large modulation indexes. The output from the multiplier 507 is passed to a buffer 508, such as a 128-tap FIFO, and the buffer 508 output gets passed to the signature detector 509 (correlation metric comprises converting the modulation of the first and/or second portion). See paragraphs 0083-0085.)
Regarding claim 10, D1 discloses wherein the data packet comprises a third portion including information specific to the data packet and a fourth portion comprising corresponding information to the third portion, and the radio receiver device is be arranged to use the first and fourth portions to improve the estimate of carrier frequency offset between the radio signal and the radio receiver device (Referring to Figures 1-3, packaging a protocol packet (transmitted and received) to include a predetermined bit sequence with a specified prefix (first, second, third and fourth portions used to improve estimate of CFO), one or more signature elements, and a specified suffix at a possibly known or negotiated location in the protocol packet. The predetermined bit sequence includes an m-bit prefix, one or more copies of an L-bit signature segment, and an m-bit suffix, where the m-bit prefix is identical to the last m-bits of the L-bit signature segment and where the m-bit suffix is identical to the first m-bits of the L-bit signature segment. The predetermined bit sequence includes a single signature segment, the m-bit prefix and m-bit suffix may be predetermined values known to the transmitting and receiving devices without any relationship to the signature segment. See paragraphs 0020-0022.)
Regarding claim 11, D1 discloses arranged to determine a first intermediate CFO estimate using said first and second portions, to determine a second intermediate CFO estimate using third and fourth portions, and to estimate the carrier frequency offset between the radio signal and the radio receiver device by calculating an average of the first and second intermediate CFO estimates (Referring to Figures 1-3, Wherever located in the BLE packet 27, the CFOF sequence 28 may be transmitted in a single BLE packet transmission event 26 where the first wireless device 21 transmits the BLE packet 27 at transmission time T1n and where the second wireless device 24 receives the BLE packet 27 at reception time T2n. At the receiving wireless device 24, a CFOF sequence detector is provided to detect each CFOF sequence and produce a CFO estimate (or an average of multiple CFO estimates, if applicable) (first and second intermediate CFO and estimate CFO based on average) between the LO clocks 22, 25. See paragraphs 0028-0030.)
Regarding claim 12, D1 discloses arranged to calculate a first correlation metric using the first portion and the second portion, to calculate a second correlation metric using the third portion and a fourth portion, to calculate a combined correlation metric from said first and second correlation metrics and to estimate the carrier frequency offset between the radio signal and the radio receiver device using the combined correlation metric (Referring to Figures 1-3, Wherever located in the BLE packet 27, the CFOF sequence 28 may be transmitted in a single BLE packet transmission event 26 where the first wireless device 21 transmits the BLE packet 27 at transmission time T1n and where the second wireless device 24 receives the BLE packet 27 at reception time T2n. At the receiving wireless device 24, a CFOF sequence detector is provided to detect each CFOF sequence and produce a CFO estimate (or an average of multiple CFO estimates, if applicable) (first and second metric and estimate CFO based on combined correlation metric) between the LO clocks 22, 25. See paragraphs 0028-0030.)
Regarding claim 13, D1 discloses wherein the preamble of the data packet comprises a synchronisation portion which includes a fixed, repeated pattern, and the radio receiver device is configured to determine an initial estimate for the carrier frequency offset between the radio signal and the radio receiver device using the synchronisation portion of the preamble (Referring to Figures 1-3, in applications where the CFOF sequence is embedded within the PDU part of the packet, such restrictions on the signature segment(s) are not necessary because the packet's SFD (sync portion, interpreted as fixed, repeated pattern as the SFD is a fixed position and repeated in subsequent packets) will be used for timing synchronization and CFO estimation. See paragraphs 0033-0035.)
Regarding claim 14, D1 discloses configured to calculate an additional correlation metric for a repeated fixed pattern in a synchronisation portion and to determine the initial estimate for the carrier frequency offset using said additional correlation metric (Referring to Figures 1-3, in applications where the CFOF sequence is embedded within the PDU part of the packet, such restrictions on the signature segment(s) are not necessary because the packet's SFD (sync portion, interpreted as fixed, repeated pattern as the SFD is a fixed position and repeated in subsequent packets) will be used for timing synchronization and CFO estimation (additional correlation metric to determine CFO). See paragraphs 0033-0035.)
Regarding claim 15, D1 discloses configured to calculate the correlation metric between the first and second portion using parts of the first and second portion having a length equal to a fixed repeated pattern in a synchronisation portion (Referring to Figures 1-3, in applications where the CFOF sequence is embedded within the PDU part of the packet, such restrictions on the signature segment(s) are not necessary because the packet's SFD will be used for timing synchronization and CFO estimation (the system is also configurable to match the recited limitations, and the sequence is configurable as well to match the recited limitations). See paragraphs 0033-0035.)
Regarding claim 16, D1 discloses configured to compensate for the initial estimate of the carrier frequency offset estimated using the synchronisation portion and then to compensate for the carrier frequency offset estimated using the first and second portions (Referring to Figures 1-3, in applications where the CFOF sequence is embedded within the PDU part of the packet, such restrictions on the signature segment(s) are not necessary because the packet's SFD will be used for timing synchronization and CFO estimation (the system is also configurable to match the recited limitations, and the sequence is configurable as well to match the recited limitations for compensation). See paragraphs 0033-0035.)
Regarding claim 17, D1 discloses configured to calculate a weighted average of a previously-estimated or otherwise previously-known carrier frequency offset and the carrier frequency offset estimated using the correlation metric (Referring to Figures 1-3, Wherever located in the BLE packet 27, the CFOF sequence 28 may be transmitted in a single BLE packet transmission event 26 where the first wireless device 21 transmits the BLE packet 27 at transmission time T1n and where the second wireless device 24 receives the BLE packet 27 at reception time T2n. At the receiving wireless device 24, a CFOF sequence detector is provided to detect each CFOF sequence and produce a CFO estimate (or an average of multiple CFO estimates, if applicable) (first and second intermediate CFO and estimate CFO based on average, weighted interpreted as unity) between the LO clocks 22, 25. See paragraphs 0028-0030.)
Regarding claim 18, D1 discloses arranged to use the correlation metric to derive a phase offset between the first and second portions (Referring to Figures 1-3, When enabled by the control signal 304, the CFOF pre-processor 306 is configured to convert the received input I/Q samples 302 into phase values by discriminating the input, and then calculating the phase change over each symbol duration. The detected phase change values are output as a sequence of output values 307 to the CFOF signature segment detector 308. To control the timing and reduce power consumption, the input control signal 304 enables the CFOF pre-processor 306 at the beginning of the CFOF sequence and disables the CFOF pre-processor 306 at the end of the CFOF sequence. See paragraphs 0056-0058.)
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.
Claim(s) 3 is rejected under 35 U.S.C. 103 as being unpatentable over D1 in view of Lopez et al. (US 2022/0271985 A1), hereinafter referred to as D2.
Regarding claim 3, D1 does not disclose wherein the data packet is an IEEE 802.11 ax High Efficiency Extended Range Single User format packet.
D2 teaches a method and apparatus for signaling in WLAN which comprises the IEEE 802.11ax packet transmission. See paragraphs 0074-0076.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to implement the IEEE 802.11ax protocol of D2 in the system of D1. One of ordinary skill in the art before the effective filing date of the invention would have been motivated to do so to comply with well-known standards and improve system operability.
Claim(s) 4 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over D1 in view of D2 in further view of Raissinia et al. (US 2022/0224579 A1), hereinafter referred to as D3
Regarding claim 4, D1 does not disclose wherein the first portion comprises a legacy signal (L-SIG) field and the second portion comprises a repeated legacy signal field (RL-SIG).
D3 teaches the legacy portion 302 of the preamble includes an L-STF 308, an L-LTF 310, and an L-SIG 312. The non-legacy portion 304 includes a repetition of L-SIG (RL-SIG) 314, a first HE signal field (HE-SIG-A) 316, an HE short training field (HE-STF) 320, and one or more HE long training fields (or symbols) (HE-LTFs) 322. For OFDMA or MU-MIMO communications, the second portion 304 further includes a second HE signal field (HE-SIG-B) 318 encoded separately from HE-SIG-A 316. Like the L-STF 308, L-LTF 310, and L-SIG 312, the information in RL-SIG 314 and HE-SIG-A 316 may be duplicated and transmitted in each of the component 20 MHz channels in instances involving the use of a bonded channel. In contrast, the content in HE-SIG-B 318 may be unique to each 20 MHz channel and target specific STAs 104. See paragraphs 0052-0054.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to implement the IEEE 802.11ax protocol with the preamble of D3 in the system of D1 and D2. One of ordinary skill in the art before the effective filing date of the invention would have been motivated to do so to comply with well-known standards and improve system operability.
Regarding claim 5, D1 does not disclose wherein the first portion comprises a first part of a High Efficiency Signal A field and the second portion comprises a second part of a High Efficiency Signal A field.
D3 teaches the PPDU 300 may be formatted as a High Efficiency (HE) WLAN PPDU in accordance with the IEEE 802.11ax amendment to the IEEE 802.11 wireless communication protocol standard (high efficiency signal A field). The PPDU 300 includes a PHY preamble including a legacy portion 302 and a non-legacy portion 304. The PPDU 300 may further include a PHY payload 306 after the preamble, for example, in the form of a PSDU including a data field 324. See paragraphs 0052 and 0111.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to implement the IEEE 802.11ax protocol with the preamble of D3 in the system of D1 and D2. One of ordinary skill in the art before the effective filing date of the invention would have been motivated to do so to comply with well-known standards and improve system operability.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Porat et al. (US 2022/0123910 A1) - Receive feedback from the another wireless communication device that is based on the another wireless communication processing the at least the portion of the NDP that is received via the fewer than all of the plurality of sub-channels of the communication channel. In one example, the generated NDP includes at least one signal field (SIG) field therein that includes information to specify a preamble puncturing option or the information is transmitted in a previous packet.
Martinez et al. (US 2022/0038318 A1) - Receiving a first packet, subsequently, at the receiver, receiving a second packet, and determining whether the second packet is a repetition of the first packet based on wireless communications channel estimation information associated with the first and second packets.
Bradley et al. (US 2024/0129165 A1) - Performing correlation operations on the plurality of signal samples to generate a predetermined number of correlation peaks; comparing the generated correlation peaks with a variable dynamic threshold; and calculating timing and/or frequency of the digitally modulated signal using the outcome of the comparing step.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DONALD L MILLS whose telephone number is (571)272-3094. The examiner can normally be reached Monday through Friday from 9-5 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Yemane Mesfin can be reached at 571-272-3927. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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DONALD L. MILLS
Primary Examiner
Art Unit 2462
/Donald L Mills/ Primary Examiner, Art Unit 2462
Prosecution Insights