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 .
Response to Amendment
Applicant’s submission filed on 06/23/2026 has been entered. Claims 1-7 are pending in the application.
Response to Arguments
Applicant' s arguments with respect to claims 4-7 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Applicant's arguments filed 06/23/2026 have been fully considered but they are not persuasive.
With regard to applicant’s remark on claim 1 (on pages 5-6), applicant argues that Eberlein fails to disclose or suggest “dropping samples in a cyclic prefix having a length L and forming a set of complex samples K…” Specifically, Applicant contends that column 8, lines 42-25 of Eberlein merely describes assembling an MCM symbol in the frequency domain at the transmitter, and does not teach dropping cyclic prefix samples at the receiver.
Applicant’s argument is limiting Eberlein’s disclosure to cited for transmitter-side symbol formation, while not considering Eberlein’s disclosure of receiver-side processing. Eberlein teaches receiver-side guard interval removal (i.e., dropping samples in a cyclic prefix/guard interval) prior to performing Fast Fourier Transform (FFT) processing. Specifically:
- Col. 2, lines 17-19 states: “After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138.”
- Col. 2, lines 19-23 states: “the useful MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra”
- FIG. 7 depicts block 138 as “guard interval removal” feeding directly into FFT block 140.
Dropping cyclic prefix (guard interval) samples to yield a set of K useful complex subcarrier samples for FFT processing is a well-known, fundamental operational requirement of OFDM and DAB receivers. Eberlein performs this operation via guard interval removal unit 138.
Accordingly, claim 1-3 remains obvious over Eberlein in combination with Abdi and Sakai.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-3 are rejected under 35 U.S.C. 103 as being unpatentable over Eberlein et al. (US 6,931,084 B1), hereinafter “EBERLEIN” in view of Abdi et al. (US 2016/0316445 A1), hereinafter “ABDI” in view of Sakai et al. (US 2010/0202552 A1), hereinafter “SAKAI” .
Regarding claim 1, EBERLEIN teaches, ‘A method to enhance Gaussian and Rayleigh sensitivity performance of Digital Audio Broadcast (DAB) receivers, the method comprises the steps of:’ (Related Col 1, lines 21-23, the present invention generally relates to broadcasting of digital data to mobile receivers over time-variant multipath channels. Col. 1, lines 23-27, the present invention is particularly useful in multipath environments with low channel coherence time… applied to systems implementing a multicarrier modulation scheme. Col. 2, lines 56-58, A system applying such a mapping scheme is defined in the European Telecommunication standard ETS 300 401 (EU147-DAB)):
‘dropping samples in a cyclic prefix having a length L and forming a set of complex samples K, where K is a number of frequency subcarriers in a DAB transmission mode are formed from a set of next K complex samples;’ (Related Col. 2, lines 17-19, After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138. Related Col. 2, lines 19-23, The useful MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140. Related FIG. 7 (Guard Interval Removal block 138). Col. 8, lines 39-42, One MCM symbol comprising NFFT subcarriers is assembled from NFFT-K-1 guard band symbols… K DQPSK subcarrier symbols. Col. 2, lines 13-18, a reference symbol extracting unit 136 extracts the framing information, i.e. the reference symbol, from the MCM symbol coming from the receiver front end 132. After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138);
‘evaluating a subsequent step FFT of length K to generate frequency domain samples;’ (Related Col. 2, lines 19-23, provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra. Related FIG. 7 (Block 140). Col. 2, lines 21-23, MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra);
‘differentially demodulating the frequency domain samples of successive OFDM symbols (100) to estimate subcarrier level Quadrature Phase Shift Keying (QPSK) symbols and the set of complex samples are marked as r1k (109); (Related Col. 2, lines 58-62, uses Differential Quadrature Phase Shift Keying (DQPSK) to encode every two bits into a 0, 90, 180 or 270 degrees phase difference. Col. 9, lines 38-54, The output of the fast Fourier transformator is applied to the de-mapper, which performs a differential de-mapping along the frequency axis. The output of the de-mapper are the respective phase shifts for the subcarriers. The output of the de-mapper 142… is shown… only the encoded phase shifts, 0°, 90°, 180° or 270° are present);
‘differentially demodulating output frequency domain samples of successive OFDM symbols (100) corresponding to this FFT to estimate a second set of subcarrier level QPSK symbols r2k (110);’ (Related FIG. 4 (Block 142). Col. 11, lines 20-23, A second embodiment of an echo phase offset correction algorithm… used in connection with multipath channels that have up to two strong path echoes);
‘and processing the resultant K complex samples (111) of the demodulator by the channel splitter and subsequently, the channel decoded to retrieve the information bit stream.’ (Col. 2, lines 24-26, Thereafter, the sequence of spectra is provided to a carrier-bit mapper 142 in which the serial bitstream is recovered. This serial bitstream is provided to a data sink 144).
EBERLEIN does not explicitly teach but ABDI teaches, ‘evaluating Fast Fourier Transforms (FFT) at multiple positions of Orthogonal Frequency Division Multiplexing (OFDM) symbols (100);’ (ABDI – Related Paragraph [0009], executing an FFT per OFDM symbol of the PRS for each FFT window of the FFT window pair, FIG. 1 (Blocks 10). [Paragraph [0042], Use frequency-domain processing over two FFT windows… to cover timing ranges beyond the CP. Paragraph [0051], carrying out one FFT per OFDM symbol for each FFT window (10));
‘computing differential demodulation and subsequently combining post differential demodulation subcarrier constellation symbols;’ (ABDI – Related Paragraph [0009], combining vectors based on respective first FFT output vectors. Paragraph [0052], Non-coherent or coherent combining of the two output vectors per OFDM symbol can then be performed… contains an iFFT (20) that is used to convert the frequency domain signal to a time domain signal);
‘wherein a second peak position in the channel impulse response is additionally utilized and the K complex samples beginning from the second peak position are collected;’ (ABDI – Related Paragraph [0009], executing an FFT per OFDM symbol… for each FFT window of the FFT window pair… obtaining a first FFT output vector per OFDM symbol of each FFT window. Paragraph [0047], Multiple instances of the algorithm can be run in parallel with different FFT windows (for example for search windows of different cells). Paragraph [0042], Use frequency-domain processing over two FFT windows and combine the signals to cover timing ranges beyond the CP [cyclic prefix]);
‘evaluating FFT of size K (104, 105) on the K complex samples;’ (ABDI – Related Paragraph [0009], executing an FFT per OFDM symbol… for each FFT window of the FFT window pair. Paragraph [0051], first stage of the processing… comprises carrying out one FFT per OFDM symbol for each FFT window (10)… ‘from window 2' (12) represents the second window);
‘performing Subcarrier QPSK combination (108) on r2k (110) and r1k (109);’ (ABDI – Related Paragraph [0009], combining vectors based on respective first FFT output vectors. Paragraph [0115], weight each iFFT output by the amplitude of its max value, and perform coherent combining before taking the power of the output);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of ABDI with EBERLEIN because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of ABDI into EBERLEIN is that ABDI provides time domain accumulation or interpolation carried out per FFT window based on the first FFT output vectors to obtain a second output vector per FFT window; and wherein the
combining is coherent combining carried out between the two second vectors to obtain an iFFT input; and executing the iFFT on the input. (See paragraph [0010], ABDI)
EBERLEIN and ABDI do not explicitly teach but SAKAI teaches, ‘retrieving peak positions (102, 103) of a channel impulse response using the channel impulse response peak estimator (101);’ (SAKAI – Paragraph [0033], The maximum value detecting circuit 124 detects a peak position of the amplitude component found by the amplitude finding circuit 123. Paragraph [0066], symbol timing that precisely indicates the boundary between the transmission symbols);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of SAKAI with EBERLEIN and ABDI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of SAKAI into EBERLEIN and ABDI is that SAKAI provides an OFDM demodulator including a symbol integration circuit (131) for integrating a guard correlation signal in a symbol number direction, and an offset removal circuit (132) for removing an offset from the guard correlation signal integrated in the symbol number direction. An amplitude component due to the disturbing wave, which amplitude component is included in the guard correlation signal, is cancelled by the integration in the symbol number direction, so that it is possible to successfully remove the offset from the guard correlation signal. Therefore, it is possible to obtain symbol timing more precisely by use of a maximum value detecting circuit (124), and further, calculate a phase rotation amount more precisely by use of a phase
finding circuit (125). (See Abstract, SAKAI)
Regarding claim 2, EBERLEIN, ABDI and SAKAI teach, The method to enhance Gaussian and Rayleigh sensitivity performance of Digital Audio Broadcast receivers, as claimed in claim 1,
EBERLEIN does not explicitly teach but ABDI teaches, ‘wherein, the method includes utilizing more than two peaks from the channel impulse response’ (ABDI – Paragraph [0127], If necessary ( e.g. if the time region spread by the different values of Expected-RSTD and RSTD-Uncertainty for different cells is large), the measured Cells can be grouped in groups… and the method applied to different pairs of FFT windows in parallel)
‘and adding corresponding computational blocks FFT, DQPSK (106, 107)’ (ABDI – Paragraph [0135], To measure the Ncell eNodeBs, we have 2 common FFT then one iFFT per Cell. We also need to add the pilot compensation per Cell)
‘and the subcarrier QPSK combiner.’ (ABDI – Paragraph [0115], We can thus weight each iFFT output by the amplitude of its max value, and perform coherent combining before taking the power of the output).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of ABDI with EBERLEIN because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of ABDI into EBERLEIN is that ABDI provides time domain accumulation or interpolation carried out per FFT window based on the first FFT output vectors to obtain a second output vector per FFT window; and wherein the
combining is coherent combining carried out between the two second vectors to obtain an iFFT input; and executing the iFFT on the input. (See paragraph [0010], ABDI)
Regarding claim 3, EBERLEIN, ABDI and SAKAI teach, The method to enhance Gaussian and Rayleigh sensitivity performance of Digital Audio Broadcast receivers, as claimed in claim 1,
EBERLEIN further teaches, ‘wherein, the method includes transmission schemes which involves OFDM’ (Col. 1, lines 28-29, Multi-carrier modulation (MCM) is also known as orthogonal frequency division multiplexing (OFDM))
‘and Differential Multi Phase Shift Keying (DMPSK) instead of DQPSK.’ (Col. 7, lines 53-57, According to FIG. 2, a quadrature phase shift keying (QPSK) is used for mapping... However, other M-ary mapping schemes (MPSK) like 2-PSK, 8-PSK… are possible).
Claims 4-7 are rejected under 35 U.S.C. 103 as being unpatentable over EBERLEIN in view of ABDI in view of SAKAI in view of Du et al. (US 2009/0110135 A1), hereinafter “DU” .
Regarding claim 4, EBERLEIN teaches, ‘A method to enhance digital audio broadcast (DAB) receivers, the method comprising:’ (Col. 1, lines 18-25, The present invention generally relates to broadcasting of digital data to mobile receivers over time-variant multipath channels. More specifically, the present invention is particularly useful in multipath environments with low channel coherence time, i.e. rapidly changing channels. In preferred embodiments, the present invention can be applied to systems implementing a multicarrier modulation scheme. Col. 2, lines 56-58, A system applying such a mapping scheme is defined in the European Telecommunication standard ETS 300 401 (EU147-DAB)):
‘forming a first set of K samples starting from a first peak position;’ (Col. 2, lines 17-23, After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138. The result of the signal processing performed so far in the MCM receiver are the useful MCM symbols. The useful MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra from the useful symbols. Col. 12, lines 42-26. At the DFT output of the receiver the decision variables ek=akHk are obtained with k=1,2, …, K of the active subcarrier);
‘differentially demodulating using demodulators the frequency domain samples of successive OFDM symbols to estimate subcarrier level QPSK symbols’ (Col. 2, lines 59-61, Differential Quadrature Phase Shift Keying (DQPSK) to encode every two bits into a 0, 90, 180 or 270 degrees phase difference between two subcarriers. Col. 8, lines 42-25, The output of the fast Fourier transformator is applied to the de-mapper, which performs a differential de-mapping along the frequency axis)
‘and processing the K complex samples of the demodulators to retrieve an information bit stream.’ (Col. 2, lines 24-26, Thereafter, the sequence of spectra is provided to a carrier-bit mapper 142 in which the serial bitstream is recovered. This serial bitstream is provided to a data sink 144).
EBERLEIN does not explicitly teach but ABDI teaches, ‘forming a second set of K samples starting from a second peak position;’ (ABDI – Paragraph [0009], executing an FFT per OFDM symbol of the PRS for each FFT window of the FFT window pair; obtaining a first FFT output vector per OFDM symbol of each FFT window. Paragraph [0127], If necessary… the measured Cells can be grouped… the method applied to different pairs of FFT windows in parallel. Paragraphs [0109]-[0110], choosing the start of the first FFT window at ExpectedRSTD-RSTDUncertainty);
‘evaluating Fast Fourier Transforms (FFT) of the first set of K samples and the second set of K samples to generate frequency domain samples;’ (ABDI – Paragraph [0009], executing an FFT per OFDM symbol of the PRS for each FFT window of the FFT window pair; obtaining a first FFT output vector per OFDM symbol of each FFT window. Paragraph [0051], the first stage of the processing… comprises carrying out one FFT per OFDM symbol for each FFT window (10)… This results in two FFT output vectors per OFDM symbol);
‘to mark the first set of K samples as r1k and the second set of K samples as r2k;’ (ABDI – Paragraphs [0072]-[0074], Let us denote: X1 (n) and X2(n) the corresponding values we have on 1st FFT window (40…) and 2nd FFT window (41…), respectively);
‘performing subcarrier combination on r1k and r2k;’ (ABDI – Paragraph [0009], combining vectors based on respective first FFT output vectors. Paragraph [0084], A more efficient combination method is the well-known maximum ratio combining where each contribution is weighted by a coefficient. Paragraph [0053], Coherent combining (16) is carried out between these two vectors);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of ABDI with EBERLEIN because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of ABDI into EBERLEIN is that ABDI provides time domain accumulation or interpolation carried out per FFT window based on the first FFT output vectors to obtain a second output vector per FFT window; and wherein the
combining is coherent combining carried out between the two second vectors to obtain an iFFT input; and executing the iFFT on the input. (See paragraph [0010], ABDI)
EBERLEIN and ABDI do not explicitly teach but SAKAI teaches, ‘receiving a plurality of peak positions of a channel impulse response at a channel impulse response peak estimator;’ (SAKAI – Paragraph [0033], The maximum value detecting circuit 124 detects a peak position of the amplitude component found by the amplitude finding circuit 123. Paragraph [0132], it possible to precisely detect a boundary between transmission symbols);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of SAKAI with EBERLEIN and ABDI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of SAKAI into EBERLEIN and ABDI is that SAKAI provides an OFDM demodulator including a symbol integration circuit (131) for integrating a guard correlation signal in a symbol number direction, and an offset removal circuit (132) for removing an offset from the guard correlation signal integrated in the symbol number direction. An amplitude component due to the disturbing wave, which amplitude component is included in the guard correlation signal, is cancelled by the integration in the symbol number direction, so that it is possible to successfully remove the offset from the guard correlation signal. Therefore, it is possible to obtain symbol timing more precisely by use of a maximum value detecting circuit (124), and further, calculate a phase rotation amount more precisely by use of a phase
finding circuit (125). (See Abstract, SAKAI)
EBERLEIN, ABDI, and SAKAI do not explicitly teach but DU teaches, ‘frame synchronizing the first set of K samples and the second set of K samples to estimate a position of a NULL symbol in each sequence;’(DU – Paragraph [0006], In particular, for DAB systems the first symbol of each transmission frame is a NULL symbol, where no signal is sent… The NULL symbol is used for frame timing and coarse synchronization. Whereas the PRS can be used for fine synchronization);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of DU with EBERLEIN, ABDI and SAKAI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of DU into EBERLEIN, ABDI and SAKAI is DU provides that in DAB/OPFDM transmission frame structures, the NULL symbol is positioned as the first symbol of each frame specifically to enable this required coarse frame timing synchronization prior to fine timing alignment. Identifying frame boundaries in a DAB environment, establishing NULL symbol-based coarse frame alignment prevents frame-level alignment errors and enhancing overall receiver sensitivity. (See paragraphs [0005]-[0006], [0008], DU)
Regarding claim 5, EBERLEIN, ABDI and SAKAI teach, The method to enhance Gaussian and Rayleigh sensitivity performance of Digital Audio Broadcast receivers, as claimed in claim 1, further comprising, EBERLEIN further teaches, ‘and collecting the K complex samples beginning from the largest peak position.’ (Col. 2, lines 17-23, After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138. The result of the signal processing performed so far in the MCM receiver are the useful MCM symbols. The useful MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra from the useful symbols. Col. 12, lines 42-26, At the DFT output of the receiver the decision variables ek=akHk are obtained with k=1,2, …, K of the active subcarrier).
EBERLEIN, ABDI and SAKAI do not explicitly teach but DU teaches, ‘utilizing a largest peak position in the channel impulse response;’ (DU – Paragraphs [0027]-[0028], Using Equation (3), the strongest path p* at i*can be found. Therefore, the sample location of the corresponding path can be I max =i *M. The noise power can be estimated 112 by… relative to the location of the strongest path (Claim 3). Claim 2, step of finding a strongest path and its location from a plurality of path power computed from the channel impulse response after the converting step);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of DU with EBERLEIN, ABDI and SAKAI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of DU into EBERLEIN, ABDI and SAKAI is DU provides that in DAB/OPFDM transmission frame structures, the NULL symbol is positioned as the first symbol of each frame specifically to enable this required coarse frame timing synchronization prior to fine timing alignment. Identifying frame boundaries in a DAB environment, establishing NULL symbol-based coarse frame alignment prevents frame-level alignment errors and enhancing overall receiver sensitivity. (See paragraphs [0005]-[0006], [0008], DU)
Regarding claim 6, EBERLEIN, ABDI, SAKAI and DU teach, The method to enhance digital audio broadcast (DAB) receivers of claim 4, further comprising, EBERLEIN, ABDI, and SAKAI do not explicitly teach but DU teaches, ‘performing channel impulse response peak estimation on a frame synchronized DAB symbol.’ (DU – Paragraph [0022], Once signal acquisition is achieved, signal reception begins from the next transmission frame. For each transmission frame, fine timing synchronization is performed using the PRS in the synchronization channel, such that a fast Fourier transform (FFT) window can be properly positioned for minimum inter-symbol interference. Paragraph [0027], Using Equation (3), the strongest path p* at i*can be found. Therefore, the sample location of the corresponding path can be I max =i *M. Claim 2, step of finding a strongest path and its location from a plurality of path power computed from the channel impulse response after the converting step).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of DU with EBERLEIN, ABDI and SAKAI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of DU into EBERLEIN, ABDI and SAKAI is DU provides that in DAB/OPFDM transmission frame structures, the NULL symbol is positioned as the first symbol of each frame specifically to enable this required coarse frame timing synchronization prior to fine timing alignment. Identifying frame boundaries in a DAB environment, establishing NULL symbol-based coarse frame alignment prevents frame-level alignment errors and enhancing overall receiver sensitivity. (See paragraphs [0005]-[0006], [0008], DU)
Regarding claim 7, EBERLEIN teaches, ‘A method to enhance digital audio broadcast (DAB) receivers, the method comprising:’ (Col. 1, lines 18-25, The present invention generally relates to broadcasting of digital data to mobile receivers over time-variant multipath channels. More specifically, the present invention is particularly useful in multipath environments with low channel coherence time, i.e. rapidly changing channels. In preferred embodiments, the present invention can be applied to systems implementing a multicarrier modulation scheme. Col. 2, lines 56-58, A system applying such a mapping scheme is defined in the European Telecommunication standard ETS 300 401 (EU147-DAB)):
‘forming a first set of K samples starting from a first peak position;’ (Col. 2, lines 17-23, After the extraction of the reference symbol, the MCM signal is applied to a guard interval removal unit 138. The result of the signal processing performed so far in the MCM receiver are the useful MCM symbols. The useful MCM symbols output from the guard interval removal unit 138 are provided to a fast Fourier transform unit 140 in order to provide a sequence of spectra from the useful symbols. Col. 12, lines 42-26. At the DFT output of the receiver the decision variables ek=akHk are obtained with k=1,2, …, K of the active subcarrier);
‘differentially demodulating using demodulators the frequency domain samples of successive OFDM symbols to estimate subcarrier level QPSK symbols’ (Col. 2, lines 59-61, Differential Quadrature Phase Shift Keying (DQPSK) to encode every two bits into a 0, 90, 180 or 270 degrees phase difference between two subcarriers. Col. 8, lines 42-25, The output of the fast Fourier transformator is applied to the de-mapper, which performs a differential de-mapping along the frequency axis)
‘and processing the K complex samples of the demodulators to retrieve an information bit stream.’ (Col. 2, lines 24-26, Thereafter, the sequence of spectra is provided to a carrier-bit mapper 142 in which the serial bitstream is recovered. This serial bitstream is provided to a data sink 144).
EBERLEIN does not explicitly teach but ABDI teaches, ‘forming a second set of K samples starting from a second peak position;’ (ABDI – Paragraph [0009], executing an FFT per OFDM symbol of the PRS for each FFT window of the FFT window pair; obtaining a first FFT output vector per OFDM symbol of each FFT window. Paragraph [0127], If necessary… the measured Cells can be grouped… the method applied to different pairs of FFT windows in parallel. Paragraphs [0109]-[0110], choosing the start of the first FFT window at ExpectedRSTD-RSTDUncertainty);
‘evaluating Fast Fourier Transforms (FFT) of the first set of K samples and the second set of K samples to generate frequency domain samples;’ (ABDI – Paragraph [0009], executing an FFT per OFDM symbol of the PRS for each FFT window of the FFT window pair; obtaining a first FFT output vector per OFDM symbol of each FFT window. Paragraph [0051], the first stage of the processing… comprises carrying out one FFT per OFDM symbol for each FFT window (10)… This results in two FFT output vectors per OFDM symbol);
‘to mark the first set of K samples as r1k and the second set of K samples as r2k;’ (ABDI – Paragraphs [0072]-[0074], Let us denote: X1 (n) and X2(n) the corresponding values we have on 1st FFT window (40…) and 2nd FFT window (41…), respectively);
‘performing subcarrier combination on r1k and r2k;’ (ABDI – Paragraph [0009], combining vectors based on respective first FFT output vectors. Paragraph [0084], A more efficient combination method is the well-known maximum ratio combining where each contribution is weighted by a coefficient. Paragraph [0053], Coherent combining (16) is carried out between these two vectors);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of ABDI with EBERLEIN because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of ABDI into EBERLEIN is that ABDI provides time domain accumulation or interpolation carried out per FFT window based on the first FFT output vectors to obtain a second output vector per FFT window; and wherein the
combining is coherent combining carried out between the two second vectors to obtain an iFFT input; and executing the iFFT on the input. (See paragraph [0010], ABDI)
EBERLEIN and ABDI do not explicitly teach but SAKAI teaches, ‘receiving a plurality of peak positions of a channel impulse response at a channel impulse response peak estimator;’ (SAKAI – Paragraph [0033], The maximum value detecting circuit 124 detects a peak position of the amplitude component found by the amplitude finding circuit 123. Paragraph [0132], it possible to precisely detect a boundary between transmission symbols);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of SAKAI with EBERLEIN and ABDI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of SAKAI into EBERLEIN and ABDI is that SAKAI provides an OFDM demodulator including a symbol integration circuit (131) for integrating a guard correlation signal in a symbol number direction, and an offset removal circuit (132) for removing an offset from the guard correlation signal integrated in the symbol number direction. An amplitude component due to the disturbing wave, which amplitude component is included in the guard correlation signal, is cancelled by the integration in the symbol number direction, so that it is possible to successfully remove the offset from the guard correlation signal. Therefore, it is possible to obtain symbol timing more precisely by use of a maximum value detecting circuit (124), and further, calculate a phase rotation amount more precisely by use of a phase finding circuit (125). (See Abstract, SAKAI)
EBERLEIN, ABDI, and SAKAI do not explicitly teach but DU teaches, performing channel impulse response peak estimation on a frame synchronized DAB symbol;’(DU – Paragraph [0006], In particular, for DAB systems the first symbol of each transmission frame is a NULL symbol, where no signal is sent… The NULL symbol is used for frame timing and coarse synchronization. Whereas the PRS can be used for fine synchronization. Paragraph [0022], Once signal acquisition is achieved, signal reception begins from the next transmission frame. For each transmission frame, fine timing synchronization is performed using the PRS in the synchronization channel, such that a fast Fourier transform (FFT) window can be properly positioned for minimum inter-symbol interference. Paragraph [0027], Using Equation (3), the strongest path p* at i*can be found. Therefore, the sample location of the corresponding path can be I max =i *M. Claim 2, step of finding a strongest path and its location from a plurality of path power computed from the channel impulse response after the converting step);
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have known to combine the teachings of DU with EBERLEIN, ABDI and SAKAI because both are in the same/similar field of endeavor. The advantage of incorporating the above limitation(s) of DU into EBERLEIN, ABDI and SAKAI is DU provides that in DAB/OPFDM transmission frame structures, the NULL symbol is positioned as the first symbol of each frame specifically to enable this required coarse frame timing synchronization prior to fine timing alignment. Identifying frame boundaries in a DAB environment, establishing NULL symbol-based coarse frame alignment prevents frame-level alignment errors and enhancing overall receiver sensitivity. (See paragraphs [0005]-[0006], [0008], DU)
Conclusion
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 HAESHIL J CHOI whose telephone number is (703) 756-5409. The examiner can normally be reached Monday thru Friday ET.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jae Y Lee can be reached on 571-270-3936. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/HAESHIL JESSICA CHOI/Examiner, Art Unit 2479 /JAE Y LEE/ Supervisory Patent Examiner, Art Unit 2479
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