WO2009076487A1 - Procédés de rapport de qualité de canal, circuits et systèmes - Google Patents

Procédés de rapport de qualité de canal, circuits et systèmes Download PDF

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Publication number
WO2009076487A1
WO2009076487A1 PCT/US2008/086316 US2008086316W WO2009076487A1 WO 2009076487 A1 WO2009076487 A1 WO 2009076487A1 US 2008086316 W US2008086316 W US 2008086316W WO 2009076487 A1 WO2009076487 A1 WO 2009076487A1
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WIPO (PCT)
Prior art keywords
cqi
subbands
differential
vector
codeword
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PCT/US2008/086316
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English (en)
Inventor
Runhua Chen
Eko N. Onggosanusi
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Texas Instruments Incorporated
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Publication date
Priority claimed from US12/188,767 external-priority patent/US8179775B2/en
Priority claimed from US12/254,738 external-priority patent/US8942164B2/en
Priority claimed from US12/327,463 external-priority patent/US8699602B2/en
Application filed by Texas Instruments Incorporated filed Critical Texas Instruments Incorporated
Publication of WO2009076487A1 publication Critical patent/WO2009076487A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0028—Formatting
    • H04L1/0029—Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0456—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
    • H04B7/0478—Special codebook structures directed to feedback optimisation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0621—Feedback content
    • H04B7/0632—Channel quality parameters, e.g. channel quality indicator [CQI]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0636—Feedback format
    • H04B7/0641—Differential feedback
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0619—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal using feedback from receiving side
    • H04B7/0636—Feedback format
    • H04B7/0645—Variable feedback
    • H04B7/065—Variable contents, e.g. long-term or short-short
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0026—Transmission of channel quality indication

Definitions

  • a base station In a wireless network, a base station (designated by Node B or eNB) communicates with user equipment (UE), such as a cell phone, a laptop, or a PDA.
  • UE user equipment
  • UE user equipment
  • Base station eNB transmits reference signals or pilot signals to UE, which generates a channel estimate based on the reference signal, as impacted by interference and noise.
  • the system bandwidth is divided into frequency-domain groups or subbands that encompass resource blocks (RBs) according to group size or subband size.
  • An RB is the smallest allocation unit available in terms of frequency granularity allocated to UE by a base station scheduler module.
  • UE determines a channel quality indicator (CQI) for each RB or for each subband based on the channel estimation.
  • CQI channel quality indicator
  • the CQI metric is suitably a signal to interference noise ratio (SINR) after detection, the index to a supportable modulation and coding scheme, the index to a supportable code rate, a channel throughput measure, or other quality measure.
  • SINR signal to interference noise ratio
  • UE feeds back the CQI for each subband or RB to eNB. More favorable CQI permits a higher data transfer rate of data streams by eNB to UE.
  • MIMO multi-input multi-output
  • the number of independent data streams (number of spatial codewords) is termed the transmission rank.
  • a form of the invention involves an electronic device that includes a first circuit operable to generate at least a first and a second channel quality indicator (CQI) vector associated with a plurality of subbands for each of at least first and second spatial codewords respectively and generate a first and a second reference CQI for the first and second spatial codewords, and operable to generate a first and a second differential subbands CQI vector for each spatial codeword and generate a differential between the second reference CQI and the first reference CQI, and further operable to form a CQI report derived from the first and the second differential subbands CQI vector for each spatial codeword as well as the differential between the second reference CQI and the first reference CQI; and a second circuit operable to initiate transmission of a signal communicating the CQI report.
  • CQI channel quality indicator
  • FIGS. 1 and 2 each provide a respective system block diagram of a MIMO OFDMA receiver and transmitter for UE or eNB improved as shown in the other Figures.
  • FIG. 3 is a flow diagram of an improved UE process having different CQI reporting modes.
  • FIG. 4 is a diagram of subbands in the frequency domain for different codewords, showing an improved CQI reporting process.
  • FIG. 5 is a diagram of subbands in the frequency domain for different codewords, showing another improved CQI reporting process.
  • FIGS. 6 A and 6B are each a diagram of subbands in the frequency domain for different codewords, showing an improved Best-m Average CQI reporting process.
  • FIGS. 7 A and 7B are each a diagram of subbands in the frequency domain for different codewords, showing an improved Best-m Individual CQI reporting process.
  • FIGS. 8 A and 8B are each a diagram of subbands in the frequency domain for different codewords showing another improved Best-m Individual CQI reporting process.
  • FIGS. 9-10 are each a diagram of codewords versus subbands enumerating a process sequence for scanning-based CQI reporting.
  • FIG. 9 CQI reporting is in subband order, codeword by codeword.
  • FIG. 10 CQI reporting is in codeword order, subband by subband.
  • FIG. 11 is a pair of side-by-side flow diagrams of a user equipment UE and a base station eNB, and shows an improved process for CQI reporting in UE, and an improved process in eNB to reconstruct the CQIs for subbands of codewords from the CQI report.
  • FIG. 12 is a flow diagram of a process for use in base station eNB to apply a scanning pattern and use a subband vector SV indicating selected individual subbands for Best-m CQI reporting involving multiple codewords in a MIMO system.
  • a receiver 100 for a MIMO frequency division multiplex system is in a mobile handset 1010 or a fixed device.
  • a feedback generation portion 110 includes a precoding matrix selector 111, a channel quality indicator (CQI) computer 112, rank selector 114, and a feedback encoder 113.
  • Receive portion 105 in FIG. 1 receives data from a transmitter 150 of FIG. 2.
  • Channel estimation module 109 employs previously transmitted channel estimation pilot signals.
  • Precoding matrix information can be obtained via an additional downlink signaling embedded in the downlink control channel or in a reference signal, or from a previously selected precoding matrix.
  • Precoding matrix selector 111 determines a precoding matrix selection for the data transmission based on the channel/noise/ interference estimates from block 109, in tandem with rank selector 114 determination of a preferred rank R for number of spatial code words to be accommodated.
  • CQI is calculated based on the selected precoding matrix or its index (PMI) in a PMI codebook.
  • the precoding matrix selection and CQI are computed for the next time the user equipment UE of FIG. 1 is scheduled by the transmitter (e.g., a base station FIG. 2) to receive data.
  • Feedback encoder 113 then encodes the precoding matrix selection, CQI information and rank R and feeds them back to transmitter 150 before the data is transmitted.
  • FIG. 2 illustrates a system diagram of a transmitter 150 such as for a base station eNB 1050 in an OFDM communication system.
  • the transmitter 150 includes a transmit portion 155 and a feedback decoding portion 160.
  • the transmit portion 155 includes a modulation and coding scheme (MCS) module 156, a pre-coder module 157 and an OFDM module 158 having multiple OFDM modulators that feed corresponding transmit antennas.
  • Feedback decoding portion 160 includes a receiver module 166 and a decoder module 167.
  • MCS module 156 maps the codeword(s) to the R layers or spatial streams. Each codeword consists of FEC-encoded, interleaved, and modulated information bits. A selected modulation and coding rate for each codeword are derived from the CQI.
  • Pre- coder module 157 employs a precoding matrix selection indexed by a precoding matrix index (PMI), corresponding to receiver 100 grouping of RBs, from feedback decoder module 167. Precoder 157 linearly cross-combines the R spatial stream(s) into P output data streams.
  • PMI precoding matrix index
  • UE proceeds from BEGIN 2105 to select a hybrid CQI feedback configuration mode at a decision step 2110 which monitors configuration transmissions from eNB. If a mode called UE Configuration Mode here is selected, a step 2114 activates UE Configuration Mode unless eNB mandates a mode called eNB Configuration Mode here and a branch to a step 2118 activates the eNB Configuration Mode.
  • UE Configuration Mode and eNB Configuration Mode respectively establish parameters and controls over hybrid CQI feedback and can also define a scanning pattern or sequential feedback order, see e.g. FIG. 9-10.
  • a step 2128 provides information for step 2165 on configured CQI feedback mode.
  • step 2122 responds to configuration for CQI Relative Mode or CQI Absolute Mode or CQI Directed Mode, step 2124 for a number m of selected subbands, step 2126 specifying total number M of subbands and a width granularity number L for m selected subbands, and step 2128 specifies a Feedback Process Code for Best-m. If step 2122 establishes CQI Absolute mode, operations go to a loop having steps 2130, 2135, 2138 that select all CQI(J) such as SINR(J) in subband j that exceeds a predetermined threshold.
  • Step 2130 detects whether the threshold is exceeded by the SINR in a given sub-band j. If Yes in step 2130, then step 2135 records a one (1) at a position j (current value of index j) in a subband vector SV(j) and then goes to step 2138 to increment the index j and/or codeword index r. If No in step 2130, then operations instead record a zero (0) at position j in SV(J) and proceed to step 2138 to increment the index j.
  • step 2130 goes to a step 2145. If step 2122 establishes CQI Relative mode, a step 2140 selects a number m of subbands j of width L having, e.g., highest CQI. Step 2140 uses the parameter m established in step 2124 and M and L from step 2126, and searches all M subbands, whence step 2140 goes to step 2145.
  • step 2122 establishes a CQI Directed mode under eNB or UE Configuration Mode
  • operations go to step 2145 and directly load a subband vector SV(J) (or SV(rj)) with a particular series of ones and zeros responsive to, and/or as directed and/or specified by base station eNB or UE.
  • a subband vector SV(J) or SV(rj) is now constituted and has M elements forming a series of ones and zeros that represent whether each subband is selected or not.
  • a step 2150 counts the number of ones in subband vector SV to establish the resulting number m or m(r) of selected subbands resulting when the CQI Absolute Mode has been executed.
  • defining the subband vector (SV) as a IxM vector containing Is and Os is one exemplary method to indicate the position of the selected subbands.
  • the position of the selected subbands is reported using a compressed label or codebook index (e.g., bits joint quantized into fewer bits by UE codebook lookup using for example Iog 2 (c ⁇ ) bits, where C ⁇ denotes number of combinations of M elements taken m selected subbands at a time.
  • Step 2155 generates one or more CQI values (ki in number) for the number m of selected subbands.
  • a step 2160 generates one or more CQI values (k 2 in number) to either individually or collectively describe the un-selected subbands that are M-m in number.
  • the CQI value(s) generated in step 2160 for the un-selected subbands have a precision or accuracy that is less than the precision or accuracy of the CQI values for the number m of selected subbands generated in step 2155.
  • Step 2165 assembles the CQI values into a CQI vector, to which is associated a Feedback Process Code from step 2128, a scanning code identifying a scanning pattern (e.g., from FIG. 9-10), mode specifiers from step 2122, an identification UE_ID of the UE, CQI, rank and any other relevant configuration information or representing-information not already communicated by UE or already stored at base station eNB.
  • CQI feedback output is transmitted from each UE to base station eNB on uplink UL as a service request, or with a service request code.
  • Quantization of the CQIs can involve an absolute value of at least one CQI or an average CQI of the selected sub-bands.
  • Averaging uses arithmetic mean, geometric mean or exponential averaging, etc., as suitable.
  • RND is any appropriate rounding function such as one that rounds to the nearest value expressed in the fewer number of bits to be supported.
  • Another difference function performs a table lookup that outputs a table value to which the input values a and b are mapped by the table.
  • CQI is expressed by any of decibels dB, ratio of signal power/noise power, index to the supportable modulation and coding schemes (MCS), index to the supportable spectral efficiency, and the difference function can be chosen based on an exponential difference log[exp(a)-exp(b)] or an arithmetic difference a-b or some other difference mapping.
  • CQI feedback methodology has responded to system constraints by applying a differential wideband CQI feedback approach as an alternative to subband-specific differential CQI feedback.
  • the wideband alternative provides a limited amount of CQI feedback and thus gives an appearance of feedback bit-efficiency and sufficiency by itself.
  • subband-specific differential CQI feedback provides a more granular amount of CQI feedback and thus gives an appearance of wider feedback coverage sufficiency by itself.
  • Such alternative-process methodologies each insufficiently respond to the need for CQI feedback that is both highly efficient in terms of CQI feedback bits per subband per codeword and provides more extensive CQI feedback coverage of subbands and codewords.
  • subband-specific CQI reporting in FIG. 4 delivers such a comprehensive CQI reporting solution combining complementary parts wherein subband-specific CQIs for a given codeword are encoded differentially relative to the wideband CQI or other reference CQI (mean, median, etc.) for that codeword, and the wideband CQI (or other reference CQI) for all but one of the codewords are encoded differentially relative to the wideband CQI (or other reference CQI) for the remaining codeword.
  • both the bit-efficient feedback of differentially encoded wideband CQIs for the codewords and the bit-efficient feedback of differentially encoded subband-specific CQIs for the codewords complement one another in the FIG. 4 embodiment and other analogous embodiments herein to provide both enhanced bit-efficiency and more extensive CQI coverage of subbands and codewords for MIMO.
  • the wideband CQI of codeword 2 is encoded differentially relative to the wideband CQI of codeword 1 (CWl).
  • the reference CQI is reported with high resolution (e.g., 4-5 bits) and the subband differential CQI has smaller dynamic range reported with lower resolution (e.g., 2-3 bits).
  • Spatial differential CQI reporting one codeword is selected as reference codeword and its reference CQI value is reported with high resolution (e.g., 4 or 5 bits).
  • CQI of remaining spatial codewords is encoded differentially with respect to the reference CQI of the reference codeword and reported with lower resolution (e.g., 2-3 bits).
  • a variant embodiment relative of FIG. 4 reports individual differential CQIs designated ⁇ CQIi j CQIi, W b), for codeword CWl using lower resolution (e.g., 2-3 bits) for each subband j (or selected subband j in a Best-m set) for codeword CWl.
  • the CQI reporting feeds back individual spatial differential CQIs ⁇ CQI 1J CQI]J, differencing subband CQIs pairwise across codewords, using lower resolution (e.g., 2-3 bits) for subband j ( or each selected subband j in a Best-m set) for each codeword CW2, etc.
  • lower resolution e.g., 2-3 bits
  • wideband CQIi iW b is reported at higher resolution (e.g., 4-5 bits) for codeword CWl.
  • a process embodiment performs additional differential reporting between the differential CQI sequences of each codeword.
  • the differential CQI sequence of codeword 1 CWl as ⁇ V Mi2 . - 5I " ]
  • differential CQI sequence of codeword 2 as ⁇ 21, ⁇ 22, -- ⁇ 1 Inste ad of feeding back ⁇ 21 - ⁇ 22 --- 5 ⁇ ]
  • the process feeds back f J d ⁇ iff ( V ⁇ A"S" 2 2 1 i A—S 2 2 2 2 , .—...S 2 2 M M ⁇ J ⁇ > 1 ⁇ —S n 11 A—S 1 1 2 2 , .—...S 1 I M M ) J )/ O r/ ⁇ / ⁇ S 2j , AS 1 J where the subtraction of vectors between codewords is performed element- wise by subband j.
  • This is one example of a spatial differential between a frequency differential subbands CQI vector and another frequency differential subbands CQI
  • differential CQI can be the same or different for different differential quantities.
  • difference function f ⁇ for computing the differential of the differential CQI in some embodiments can be specified differently than difference function f ⁇ fl() for computing the differential CQIs for purposes of the subtraction of vectors.
  • “subtraction” refers to is suitably specified difference function for the element wise operation, and is not limited to particular definition of subtraction.
  • wideband CQI of CW2 is encoded differentially to wideband CQI of CWl and furthermore the frequency differential subbands CQI vector for CW2 is encoded spatially differentially to the frequency differential subbands CQI vector of CWl.
  • the differential CQI sequence (in frequency domain) is computed over the sub-band CQI set S, e.g., that is semi-statically configured by higher layer to include all the sub-bands, or only a sub-set of the sub-bands in the system bandwidth.
  • Delta Delta ( ⁇ ) is likely to have desirably reduced dynamic range compared to ⁇ S rj when there is substantial positive correlation between ⁇ Si j and A S 2J , for instance.
  • Reduced dynamic range facilitates effective compression.
  • Favorable UE geometry, high wideband SINR for all codewords, and favorable precoding matrix PM at eNB each contribute to a high positive correlation between ⁇ S lo and ⁇ S 2j (i.e., correlation between differential CQIs for different codewords r).
  • the location of the m selected subbands is jointly reported using compressed label using log 2 (c ⁇ j bits.
  • Some examples of different implementations for the performance metric are 1) maximizing the sum throughput, summed over all codewords, 2) maximizing the arithmetic/exponential average CQI over all codewords, 3) maximizing the mean CQI over all codewords, and 4) minimizing the difference between CQIs of different codewords.
  • FIGS. 6A and 6B are examples of best-m UE-selected average CQI report with spatial differential quantization.
  • spatial differential reporting is performed between the wideband CQIs of different codewords, and between the best-m average CQI (UE-selected) between different codewords, preferably using fewer bits (e.g., 2-3 bits).
  • the wideband CQI and best-m average CQI (UE-selected) of the reference codeword is also fed back with high resolution (e.g. 4-5 bits). For instance, consider a
  • FIG. 6A and 6B are each a diagram of subbands in the frequency domain for different codewords, showing wideband CQI report for unselected subbands of the first codeword, wideband CQI report for unselected subbands of the second codeword encoded differentially with respect to the wideband CQI of the first codeword (spatial delta), best-m average CQI report for selected subbands of the first codeword, and best-m average CQI report for selected subbands of the second codeword encoded differentially with respect to the best-m average CQI of the first codeword (spatial delta), and in FIG.
  • FIGS. 7A and 7B are examples of best-m UE-selected individual CQI report with spatial differential quantization. Spatial differential reporting is performed between the wideband CQIs of different codewords, and between the best-m individual CQI (UE- selected) for each selected subband j between different codewords, preferably using fewer bits (e.g., 2-3 bits). In addition, the wideband CQI and best-m individual CQI (UE- selected) for each of the selected subbands of the reference codeword is also fed back with high resolution (e.g., 4-5 bits). For instance, consider a MIMO-OFDMA system with two spatial codewords. FIGS.
  • FIG. 7A and 7B are each a diagram of subbands in the frequency domain for different codewords, showing wideband CQI report for unselected subbands of the first codeword, wideband CQI report for unselected subbands of the second codeword encoded differentially with respect to the wideband CQI of the first codeword (spatial delta), Best-m individual CQI report for each of the selected subbands of the first codeword, and Best-m individual CQI report for each of the selected subbands of the second codeword encoded differentially with respect to the Best-m individual CQI of the corresponding subband of the first codeword (spatial delta).
  • the selected (Best-m) subbands have the same subband indices across codewords
  • FIG. 7A and 7B are each a diagram of subbands in the frequency domain for different codewords, showing wideband CQI report for unselected subbands of the first codeword, wideband CQI report for unselected subbands of the second codeword encoded differentially
  • a differential encoding of the differential CQI(s) (Delta)
  • the Delta Delta is quantized for the second codeword CW2, and any other codewords CW3, etc.
  • the Delta Delta is fed back for each higher codeword CW2, etc., using lower resolution (e.g., 2 or 3-bits).
  • Joint Sub-band Selection in FIG. 8A or Independent Sub-band Selection FIG. 8B can be reported.
  • a respective indication SV(rj) of the positions of the sub-bands selected is reported for each codeword by operations in FIG. 3.
  • For the Joint case only one indication SV(j) of the best m sub-bands position is reported common to all codewords is reported for each codeword by operations in FIG. 3. Note that the definition of differential CQI is specified the same or different for different differential quantities.
  • the scanning process scans the system bandwidth according to a scanning pattern, to select one or several sub-bands.
  • Large feedback overhead of systems lacking compression is substantially reduced, which allows the amount of CQI reporting to be increased so that the entire system bandwidth is covered in the CQI report.
  • Uplink overhead is consequently decreased, uplink control signaling design is simplified and improved, uplink feedback coverage and MIMO control channel coverage are improved.
  • configurable scanning pattern CQI reporting embodiments can improve network speed and CQI feedback-related latency in UE and in eNB, and help ameliorate and solve these problems by organizing, coordinating, parallelizing and/or pipelining the CQI feedback processing herein for lower latency and higher system speed and relax constraints.
  • Scanning herein makes the index order of operations, called a scanning pattern over subband/codeword indices (j, r), more uniform from block to block in UE and coordinates with index order of operations in eNB.
  • UE operations e.g. in FIGS.
  • CQI generation, differencing, writing (storing) and reading (loading), and transmission of the CQI feedback in UEi are coordinated by using a same configurable scanning pattern.
  • the eNB receives encoded CQI feedback and on-the-fly de- differences that CQI feedback from a given UEi by the same scanning pattern in eNB as in UEi by which that CQI feedback streams into eNB.
  • CQI scanning scans a 2-dimensional matrix or space-frequency grid in both frequency domain and space domain.
  • a configurable scanning covers the frequency- space domain by transmitting a CQI report in more or less compressed form based on CQI of exhaustive non-overlapping (mutually exclusive) proper subsets ⁇ CQI(SB j , CW r ) ⁇ or averages over such subsets of the set of CQI having all indices j, r that encompass the frequency-space domain.
  • Scanning feedback is performed first in the frequency domain, and then in the spatial domain. At the beginning, the 1 st codeword is selected, and scanning feedback is performed in the frequency-domain for this codeword.
  • codeword 2 is selected and its CQI is fed back according to a scanning feedback pattern (1,2,...1O).
  • Scanning feedback is performed first in the spatial domain r, and then in the frequency domain j.
  • Various other scanning feedback processes 1) combine the scanning reporting processes shown in FIGS. 9 and 10, or 2) handle codewords having different numbers of subbands j per codeword, or 3) handle codewords not only having different numbers of subbands per codeword, but also varying widths of subbands varying with codeword index r; or 4) handle codewords having corresponding numbers M of subbands per codeword, but varying widths L of subbands j among the subbands for each codeword, or 5) CQI of a best-m spatial codeword at a sub-band in some embodiments is given more priority and scheduled to be fed back prior to unselected subbands in the space-frequency grid. Note that any of the various described scanning-based CQI reporting structures and methods of FIGS.
  • the loop kernel further includes a computation and/or read or write to storage that involves variables as a function of the indices in two- dimensional discrete index value space (r, j).
  • UEi and eNB use the same scanning pattern P 1 so that communication occurs intelligibly between them.
  • a scanning code is exchanged between UEi and eNB (or vice versa) that identifies a scanning pattern P 1 .
  • a process flow for Mean-Delta and/or Delta Delta CQI reporting can be compared with the other Figures.
  • a step 2510 quantizes the mean or median or reference or wideband CQIs Fo ,r across all subbands collectively for each codeword r.
  • a further step 2530 sends uplink feedback 2540.
  • an alternative form of uplink feedback 2540 includes a CQI feedback vector (Fo, i , D 0 , r , Ji, J r ).
  • step 2535 compresses and delivers the Delta.
  • the rank value R is implicit in the UE reporting.
  • eNB counts the number of feedback indices J in the feedback or counts the number of wideband deltas D 0,r therein plus one, or counts all the feedback values and divides by two (by count shifting rightward one), or executes some other suitable counting process.
  • the rank value R is explicitly fed back to eNB.
  • eNB step 2618 is reached after step 2614 or in case codebook feedback is not applicable at decision step 2605.
  • a step 2625 recovers the original CQIs S 1J11 - for all UEs i by a process expressed as S 1J 1 .
  • the base station eNB transmits by downlink to the UEs using composite precoding matrix PM based on the precoding matrices thus established.
  • a Best-m category of variants of FIG. 11 variously provide reporting for selected and unselected subbands, e.g. Best-m Average CQI or Best-m Individual CQI reporting, with joint quantization or not.
  • the mean or median or wideband CQI is designated s F r for the selected subbands "s" for each r-th codeword CWl, CW2, etc., and the mean or median or wideband CQI u F r for the unselected subbands "u” for each r-th codeword CWl, CW2, etc.
  • the process When spatial CQIs are quite similar in magnitude across code words r, such CQI reporting delivers compression because both the spatial CQI differences s D r and the spatial CQI differences u ⁇ r are small and easily represented with just a few bits.
  • the CQI report vector has subband vector SV and mean/median/wideband collective CQI u Fi , spatial CQI differences u ⁇ r relative to CQI u Fi for the unselected subbands for codeword CWl.
  • FIG. 12 is a flow diagram for depicting process embodiments for eNB reconstructing original CQIs S jr , or intermediately reconstructing CQI differences D jr , from the subband vector SV generated in Best-m CQI reporting.
  • FIG. 12 is a flow diagram for depicting process embodiments for eNB reconstructing original CQIs S jr , or intermediately reconstructing CQI differences D jr , from the subband vector SV generated in Best-m CQI reporting.
  • FIG. 12 provides substeps for CQI reporting processes described elsewhere herein.
  • a decision step 5120 is part of a process of scanning subband vector SV.
  • SV(j) is independent of codeword index r.
  • SV(j,r) is fed back for each spatial codeword r and used in FIG. 12 .
  • the dependence on codeword index r is shown in FIG. 12 and may be omitted for embodiments where it is not applicable.
  • a particular example of a 10- element subband vector SV is shown below the flow.
  • operations loop back to decision step 5120.
  • D(j,r) and DV(L,r) correspond to and are suitably made to take the position of various CQI S ljr or S 1J51 designations or differential D or ⁇ designations used.
  • L Lmax at a decision step 5170 and operations reach decision step 5185.
  • Lmax m, the number of Best-m selected subbands, and is a constant in some embodiments or is a function Lmax(r) of codeword r in some other embodiments.
  • operations proceed from decision step 5170 to a step 5180 that increments the index L that scans the short differential CQI vector DV.
  • Rmax i.e. equals rank R.
  • the mapping function F(s) instantiates the scanning pattern and is retrieved from a stored codebook in memory indexed by the scanning code.
  • the mapping function and the loop kernel are embedded together in a one-index loop on index s. When the loop executes, its operations are performed according to the scanning pattern.
  • the scanning pattern process is similarly applied to any process loop on indices (r,j) to instantiate a configured scanning pattern therein (e.g., FIG. 11).
  • Illustrative embodiments are not to be construed in a limiting sense. It is therefore contemplated that the appended claims and their equivalents cover any such embodiments, modifications, and embodiments as fall within the true scope of the invention.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un dispositif électronique comprenant un premier circuit (111) pouvant servir à générer au moins un premier et un second vecteur d'indicateur de qualité de canal (CQI) associé à une pluralité de sous-bandes pour chacun d'au moins un premier et un second mot de code spatial respectivement et générer un premier et un second CQI de référence pour les premier et second mots de code spatiaux, et pouvant servir à générer un premier et un second vecteur CQI de sous-bande différentiel pour chaque mot de code spatial et générer un différentiel entre le second CQI de référence et le premier CQI de référence, et pouvant également servir à former un rapport CQI dérivé du premier et du second vecteur CQI de sous-bandes différentiel pour chaque mot de code spatial de même que le différentiel entre le second CQI de référence et le premier CQI de référence; et un second circuit (113) pouvant servir à initier la transmission d'un signal communiquant le rapport CQI. D'autres dispositifs électroniques, procédés et systèmes sont également décrits.
PCT/US2008/086316 2007-12-13 2008-12-11 Procédés de rapport de qualité de canal, circuits et systèmes WO2009076487A1 (fr)

Applications Claiming Priority (10)

Application Number Priority Date Filing Date Title
US1338007P 2007-12-13 2007-12-13
US61/013,380 2007-12-13
US1980208P 2008-01-08 2008-01-08
US61/019,802 2008-01-08
US12/188,767 US8179775B2 (en) 2007-08-14 2008-08-08 Precoding matrix feedback processes, circuits and systems
US12/188,767 2008-08-08
US12/254,738 US8942164B2 (en) 2007-10-22 2008-10-20 Differential CQI for OFDMA systems
US12/254,738 2008-10-20
US12/327,463 2008-12-03
US12/327,463 US8699602B2 (en) 2007-12-13 2008-12-03 Channel quality report processes, circuits and systems

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011047588A1 (fr) * 2009-10-22 2011-04-28 华为技术有限公司 Procédé de renvoi et de réception d'informations de canal indirectes, équipement et système correspondants
CN102158307A (zh) * 2009-12-23 2011-08-17 英特尔公司 组资源分配系统和技术
CN102227098A (zh) * 2011-06-21 2011-10-26 山东大学 一种多模mimo-scfde自适应传输系统频域承载点选取方法
EP2744136A1 (fr) * 2011-08-12 2014-06-18 Fujitsu Limited Procédé d'établissement de relation de mappage, et procédé et dispositif de retour de données de qualité de voie
US10630453B2 (en) 2017-08-10 2020-04-21 At&T Intellectual Property I, L.P. Facilitating restriction of channel state information to improve communication coverage in 5G or other next generation networks

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1575234A2 (fr) * 2004-03-12 2005-09-14 Samsung Electronics Co., Ltd. Transmission d'informations sur la qualité d'un canal dans un système de multiplexage multiporteuse
US20060233127A1 (en) * 2005-04-13 2006-10-19 Nokia Corporation Efficient HARQ control and channel quality feedback reporting for multicarrier systems
EP1750407A1 (fr) * 2005-08-01 2007-02-07 Motorola, Inc. Indicateur de qualité du canal pour un canal de temps, fréquence et spatial dans un réseau d'accès radio terrestre
US20070242770A1 (en) * 2006-03-27 2007-10-18 Byoung-Hoon Kim Feedback of channel state information for MIMO and subband scheduling in a wireless communication system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1575234A2 (fr) * 2004-03-12 2005-09-14 Samsung Electronics Co., Ltd. Transmission d'informations sur la qualité d'un canal dans un système de multiplexage multiporteuse
US20060233127A1 (en) * 2005-04-13 2006-10-19 Nokia Corporation Efficient HARQ control and channel quality feedback reporting for multicarrier systems
EP1750407A1 (fr) * 2005-08-01 2007-02-07 Motorola, Inc. Indicateur de qualité du canal pour un canal de temps, fréquence et spatial dans un réseau d'accès radio terrestre
US20070242770A1 (en) * 2006-03-27 2007-10-18 Byoung-Hoon Kim Feedback of channel state information for MIMO and subband scheduling in a wireless communication system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011047588A1 (fr) * 2009-10-22 2011-04-28 华为技术有限公司 Procédé de renvoi et de réception d'informations de canal indirectes, équipement et système correspondants
CN102158307A (zh) * 2009-12-23 2011-08-17 英特尔公司 组资源分配系统和技术
CN102227098A (zh) * 2011-06-21 2011-10-26 山东大学 一种多模mimo-scfde自适应传输系统频域承载点选取方法
CN102227098B (zh) * 2011-06-21 2014-02-26 山东大学 一种多模mimo-scfde自适应传输系统频域承载点选取方法
EP2744136A1 (fr) * 2011-08-12 2014-06-18 Fujitsu Limited Procédé d'établissement de relation de mappage, et procédé et dispositif de retour de données de qualité de voie
EP2744136A4 (fr) * 2011-08-12 2015-03-25 Fujitsu Ltd Procédé d'établissement de relation de mappage, et procédé et dispositif de retour de données de qualité de voie
US10630453B2 (en) 2017-08-10 2020-04-21 At&T Intellectual Property I, L.P. Facilitating restriction of channel state information to improve communication coverage in 5G or other next generation networks
US10999042B2 (en) 2017-08-10 2021-05-04 At&T Intellectual Property I, L.P. Facilitating restriction of channel state information to improve communication coverage in 5G or other next generation networks

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