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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 03/28/2025 and 04/21/2025 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
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)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(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) 1-3, 11-13, and 20 is/are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Cao et al. (US 20220416988).
Regarding claim 1, Cao discloses a method for wireless communications performed by a computing device (Fig. 1), comprising:
generating a pattern for mapping pilot tones to a plurality of orthogonal frequency division multiplexing (OFDM) symbols (the pilots may be loaded in a pilot location of the corresponding 26-subcarrier RU. Alternatively, the entire 20 MHz signal bandwidth may be used for transmission to a single user, such that the pilots may be loaded in symbols, resulting in additional gain in performance. For example, doubling the pilots from 4 to 8 results in a performance improvement of approximately 1 dB gain (i.e., considering 20 MHz and 26-subcarrier RU); [0050]),
each of the plurality of OFDM symbols comprising a respective one or more distributed-tone resource units (dRUs) (the RU subcarriers within a symbol may be dispersed, such that a 242 sized RU may be divided into sub-RUs (e.g., nine 26 RUs where subcarriers in sub-RUs are adjacent). In an embodiment, symbols may be generated with a 26-subcarrier RU and the subcarriers may be spread across the entire bandwidth, i.e., a first symbol may have loaded subcarriers on a first data tone, a tenth data tone, a nineteenth data tone and so on. Similarly, symbol x may have loaded tones on a (mod(x-1, 9)+1)th data tone (i.e., S1 data tone), a (S1+9) data tone, and so on. Further, the RU size and bandwidth may not be limited to the 26-subcarrier RU and 20 MHz (242 sized RU) bandwidth portion, and RU location may change across multiple symbols; [0052]); and
mapping the pilot tones to the plurality of OFDM symbols according to the pattern, wherein the pattern allocates a different set of the pilot tones to the one or more dRUs within each of the plurality of OFDM symbols (the pilots of different dRUs of one size are mapped or distributed following the similar spreading rule as used to map or distribute the data tones, but the logical location of pilots varies from dRU to dRU. To this end, the dRU tone mapper 604 computes the pilot tone indices for each dRU size as “travelling” pilot tone indices which shift relative to a starting tone index of each logical RU, where the amount of shift for each dRU can be implemented by computing a pilot logical index shift value that shifts for each dRU of a given size. The computed pilot logical index shift value may be computed as a function of the dRU index value, i. For example, if a specified dRU size (e.g., a 26-tone dRU) has a plurality of pilot tones (e.g., at the 6.sup.th and 20.sup.th tones within the RU), then for the ith dRU, the dRU tone mapper 604 may compute a pilot logical index shift by k as a function of i, where k=f(i) effectively shifts the plurality of pilot tones for each dRU. In a simple example, the pilot logical index shift value k may be computed as k=mod(i-1:RU size)+1, where the modulo values increment across a range from i-1 to RU size before returning to i-1. With this example, the first 26-tone dRU has pilots on the 6.sup.th and 20.sup.th tones, the second 26-tone dRU has pilots on the 7.sup.th and 21.sup.th tones, and the third 26-tone dRU has pilots on the 8.sup.th and 22.sup.st tones; [0071]).
Regarding claim 2, Cao discloses wherein mapping the pilot tones to the plurality of OFDM symbols comprises:
allocating a first set of the pilot tones to a first set of frequency locations within a dRU of a first OFDM symbol of the plurality of OFDM symbols; and allocating a second set of the pilot tones to a second set of frequency locations within a dRU of a second OFDM symbol of the plurality of OFDM symbols (predetermined pilot tone mapping plan distributes pilot tones from each RU to the disjoint set of pilot subcarriers using a pilot spreading rule that is identical to a data spreading rule used to distribute data tones onto a disjoint set of data subcarriers included in the spreading frequency block. In other selected embodiments, the predetermined pilot tone mapping plan defines a first set of pilot locations for a plurality of distributed RUs having a RU size (RU size) by shifting a first logical pilot location by a different shift value corresponding to the RU index i as k=mod(i-1:RU size)+1. In other selected embodiments, the predetermined pilot tone mapping plan defines pilot tone indices for a plurality of distributed RUs having a size (RU size) which are evenly spread across the spreading frequency block, where each of the plurality of distributed RUs has j pilot tones. In other selected embodiments, the predetermined pilot tone mapping plan defines a first set of pilot locations for a plurality of i distributed RUs having a smallest size by shifting a first pilot location by a different shift value for each of the plurality of i distributed RUs having the smallest size; [0136]).
Regarding claim 3, Cao discloses wherein the pilot tones are mapped to the plurality of OFDM symbols, such that each OFDM symbol includes a different set of the pilot tones across time and frequency (a dispersed RU transmission may involve the transmission of a PPDU in which data tones corresponding to an RU have been distributed onto a disjoint set of subcarriers. In an embodiment, the payload may be generated for a 26-subcarrier RU, such that the first symbol may be loaded onto the first 26-subcarrier RU, while the second symbol is loaded onto the second 26-subcarrier RU, and so on in a round robin manner so that the 10th symbol is loaded onto the first 26-subcarrier RU. Such an RU may be referred to as a dispersed RU. By spreading the RU across different symbols, an average spectrum similar to that of entire loaded 20 MHz may be achieved and power boosted performance may be similar to that of loading a single RU. In similar fashion, the pilots may be loaded in a pilot location of the corresponding 26-subcarrier RU. Alternatively, the entire 20 MHz signal bandwidth may be used for transmission to a single user, such that the pilots may be loaded in symbols, resulting in additional gain in performance. RUs across symbols may not need to be the same size. In an embodiment, a 242 RU assignment may be across a signal bandwidth greater than 20 MHz, such that assignment may be similar for other larger sized RUs. Further, instead of changing the RU location every symbol, RU location may be changed across multiple symbols; [0050-0051]).
Regarding claim 11, the claim is interpreted and rejected for the reasons cited in claim 1.
Regarding claim 12, the claim is interpreted and rejected for the reasons cited in claim 2.
Regarding claim 13, the claim is interpreted and rejected for the reasons cited in claim 3.
Regarding claim 20, the claim is interpreted and rejected for the reasons cited in claim 1.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 4, 5, 10, 14, 15, and 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cao et al. (US 20220416988) in view of Park et al. (US 20260246675).
Regarding claim 4, Cao does not expressly disclose receiving an indication of the pattern from another computing device, wherein the pattern is generated after receiving the indication of the pattern.
In an analogous art, Park discloses receiving an indication of the pattern from another computing device, wherein the pattern is generated after receiving the indication of the pattern (by defining an additional subfield (e.g., information indicating whether it is a DRU, etc.) in the existing RU allocation subfield (e.g., included in a PPDU/trigger frame, etc.), the DRU may be indicated by reusing the existing signaling method; [0251]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Park into the system of Cao in order to maximize power boost by enabling maximum tone distribution within a distributed resource unit (Park; [0151]).
Regarding claim 5, the combination of Cao and Park, particularly Park discloses wherein receiving the indication comprises receiving a trigger frame for an uplink orthogonal frequency division multiple access (UL-OFDMA) transmission, the trigger frame comprising the indication (Assuming that a mapping relationship between an existing RRU index and a newly defined DRU index is predefined, the pilot subcarrier of the DRU may be allocated/defined based on the pilot subcarrier of the RRU mapped to the DRU. For example, by defining an additional subfield (e.g., information indicating whether it is a DRU, etc.) in the existing RU allocation subfield (e.g., included in a PPDU/trigger frame, etc.), the DRU may be indicated by reusing the existing signaling method. In this case, the DRU may be defined to use the same pilot subcarrier as that of the RRU mapped by the above-described mapping relationship; [0250-0251]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Park into the system of Cao in order to maximize power boost by enabling maximum tone distribution within a distributed resource unit (Park; [0151]).
Regarding claim 10, Cao discloses wherein mapping the pilot tones to the plurality of OFDM symbols comprises mapping one or more dRUs within each of the plurality of OFDM symbols (predetermined pilot tone mapping plan distributes pilot tones from each RU to the disjoint set of pilot subcarriers using a pilot spreading rule that is identical to a data spreading rule used to distribute data tones onto a disjoint set of data subcarriers included in the spreading frequency block. In other selected embodiments, the predetermined pilot tone mapping plan defines a first set of pilot locations for a plurality of distributed RUs having a RU size (RU size) by shifting a first logical pilot location by a different shift value corresponding to the RU index i as k=mod(i-1:RU size)+1. In other selected embodiments, the predetermined pilot tone mapping plan defines pilot tone indices for a plurality of distributed RUs having a size (RU size) which are evenly spread across the spreading frequency block, where each of the plurality of distributed RUs has j pilot tones. In other selected embodiments, the predetermined pilot tone mapping plan defines a first set of pilot locations for a plurality of i distributed RUs having a smallest size by shifting a first pilot location by a different shift value for each of the plurality of i distributed RUs having the smallest size; [0136]).
Cao does not expressly disclose inserting a respective one or more guard tones into the one or more dRUs.
In an analogous art, Park discloses inserting a respective one or more guard tones into the one or more dRUs (In addition to the subcarrier indices included in the 26-tone DRUs as in the examples described above, the subcarrier indices may be assigned to the 26-tone DRUs in other ways. For example, while the examples described above assume that the available subcarriers exclude guard, null, DC subcarriers, and pilot subcarriers, it is also possible to define the subcarrier indices included in each 26-tone DRU by assuming that the available subcarriers include one or more of guard, null, DC subcarriers, or pilot subcarriers; [0244]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Park into the system of Cao in order to maximize power boost by enabling maximum tone distribution within a distributed resource unit (Park; [0151]).
Regarding claim 14, the claim is interpreted and rejected for the reasons cited in claim 4.
Regarding claim 15, the claim is interpreted and rejected for the reasons cited in claim 5.
Regarding claim 19, the claim is interpreted and rejected for the reasons cited in claim 10.
Claim(s) 6, 7, and 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cao et al. (US 20220416988) in view of Taherzadeh et al. (US 20220368568).
Regarding claim 6, Cao does not expressly disclose determining one or more metrics associated with a communication link between the computing device and another computing device, wherein the pattern is generated based in part on the one or more metrics.
In an analogous art, Taherzadeh discloses determining one or more metrics associated with a communication link between the computing device and another computing device, wherein the pattern is generated based in part on the one or more metrics (PTRS pilot signals (also referred to as PTRS pilot tones) for an orthogonal frequency division multiplexing with a cyclic prefix (CP-OFDM) communication system. PTRS pilot signals may be continuous (as illustrated) or discontinuous in the time domain. For a UE 120, the PTRS signals may occupy one tone or several tones, based at least in part on a scheduled bandwidth, a frequency domain resource allocation size (e.g., a resource block (RB) allocation size), an MCS, a signal-to-noise ratio (SNR), an interference level, a port mapping, and/or another attribute that may impact the received signal quality of communication signals. A tone may be referred to as a subcarrier or a resource element (RE) in the frequency domain).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Taherzadeh into the system of Cao in order to improve channel estimation and/or performance at the receiver (Taherzadeh; [0080]).
Regarding claim 7, the combination of Cao and Taherzadeh, particularly Taherzadeh discloses wherein the one or more metrics comprise at least one of (i) a received signal strength indication (RSSI), (ii) a signal-to-noise ratio (SNR), or (iii) a bit-error rate (BER) (PTRS pilot signals (also referred to as PTRS pilot tones) for an orthogonal frequency division multiplexing with a cyclic prefix (CP-OFDM) communication system. PTRS pilot signals may be continuous (as illustrated) or discontinuous in the time domain. For a UE 120, the PTRS signals may occupy one tone or several tones, based at least in part on a scheduled bandwidth, a frequency domain resource allocation size (e.g., a resource block (RB) allocation size), an MCS, a signal-to-noise ratio (SNR), an interference level, a port mapping, and/or another attribute that may impact the received signal quality of communication signals. A tone may be referred to as a subcarrier or a resource element (RE) in the frequency domain).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Taherzadeh into the system of Cao in order to improve channel estimation and/or performance at the receiver (Taherzadeh; [0080]).
Regarding claim 16, the claim is interpreted and rejected for the reasons cited in claim 6.
Claim(s) 8, 9, 17, and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cao et al. (US 20220416988) in view of Huang et al. (US 20130128932).
Regarding claim 8, Cao does not expressly disclose wherein the pattern is generated via a compressive sensing (CS) application.
In an analogous art, Huang discloses wherein the pattern is generated via a compressive sensing (CS) application (After performing the corresponding compressive sensing channel parameter estimation process by using the pilot subcarriers, the compressive sensing channel parameter estimator 615 obtains the pilot signals, a multipath number, and a current time-frequency domain channel response and provides feedback information to the transmitter. The feedback information contains pilot pattern indexes to be transmitted back to the transmitter by the wireless communication device. The transmitter could use the pilot pattern corresponding to the pilot pattern index; [0065]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Huang into the system of Cao in order to adaptively determine the number of pilot signals by performing channel parameter estimation through compressive sensing technique such that the number of pilot subcarriers is increased when the number of multi-path channels in a channel increases (Huang; [0014]).
Regarding claim 9, the combination of Cao and Huang, particularly Huang discloses wherein the pattern comprises a respective random placement for each different set of pilot tones within the respective OFDM symbol (receiver 60 receives a plurality of pilot signals allocated in a sparse random pilot pattern from the transmitter 50. In step 1402, the receiver 60 performs a channel parameter estimation on the pilot signals by using a compressive sensing algorithm to obtain a multipath channel number. In step 1403, the receiver 60 selects a pilot pattern for a next cycle among a plurality of preconfigured sparse random pilot patterns according to the multipath channel number and a current pilot number. In step 1403, the receiver 60 transmits feedback information associated with the selected pilot pattern to the transmitter 50; [0093]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to add the features taught by Huang into the system of Cao in order to adaptively determine the number of pilot signals by performing channel parameter estimation through compressive sensing technique such that the number of pilot subcarriers is increased when the number of multi-path channels in a channel increases (Huang; [0014]).
Regarding claim 17, the claim is interpreted and rejected for the reasons cited in claim 8.
Regarding claim 18, the claim is interpreted and rejected for the reasons cited in claim 9.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Nam et al. (US 20100238877), “METHOD AND SYSTEM FOR MAPPING PILOT SIGNALS IN MULTI-STREAM TRANSMISSIONS.”
Any inquiry concerning this communication or earlier communications from the examiner should be directed to OUSSAMA ROUDANI whose telephone number is (571)272-4727. The examiner can normally be reached 8:30 AM - 5:00 PM.
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/OUSSAMA ROUDANI/ Primary Examiner, Art Unit 2413
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