WO2007046503A1 - キャリア間干渉除去装置及びこれを用いた受信装置 - Google Patents
キャリア間干渉除去装置及びこれを用いた受信装置 Download PDFInfo
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- WO2007046503A1 WO2007046503A1 PCT/JP2006/320962 JP2006320962W WO2007046503A1 WO 2007046503 A1 WO2007046503 A1 WO 2007046503A1 JP 2006320962 W JP2006320962 W JP 2006320962W WO 2007046503 A1 WO2007046503 A1 WO 2007046503A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L25/03159—Arrangements for removing intersymbol interference operating in the frequency domain
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0222—Estimation of channel variability, e.g. coherence bandwidth, coherence time, fading frequency
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L25/03821—Inter-carrier interference cancellation [ICI]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/26—Systems using multi-frequency codes
- H04L27/2601—Multicarrier modulation systems
- H04L27/2647—Arrangements specific to the receiver only
- H04L27/2649—Demodulators
- H04L27/26524—Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03006—Arrangements for removing intersymbol interference
- H04L2025/0335—Arrangements for removing intersymbol interference characterised by the type of transmission
- H04L2025/03375—Passband transmission
- H04L2025/03414—Multicarrier
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/022—Channel estimation of frequency response
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/0202—Channel estimation
- H04L25/0224—Channel estimation using sounding signals
- H04L25/0228—Channel estimation using sounding signals with direct estimation from sounding signals
- H04L25/023—Channel estimation using sounding signals with direct estimation from sounding signals with extension to other symbols
- H04L25/0232—Channel estimation using sounding signals with direct estimation from sounding signals with extension to other symbols by interpolation between sounding signals
Definitions
- the present invention relates to an inter-carrier interference canceling apparatus that reduces inter-carrier interference when receiving a multi-carrier signal in the field of mobile communications, and more particularly to a technique for improving transmission characteristics.
- OFDM orthogonal frequency division multiplexing
- various digital communications such as terrestrial digital broadcasting and IEEE802.11a.
- OFDM is a transmission method with excellent frequency utilization efficiency by frequency-multiplexing multiple narrowband digitally modulated signals with mutually orthogonal subcarriers.
- one symbol period is composed of an effective symbol period and a guard interval period, and in order to have periodicity within a symbol, a part of the signal of the effective symbol period is copied to the guard interval period. Therefore, it is possible to reduce the influence of inter-symbol interference caused by multipath interference, and it has excellent resistance to multinois interference.
- FIG. 40 is a block diagram showing the configuration of the ICI removal unit described in Non-Patent Document 3.
- Transmission path characteristic estimation section 4001 estimates the transmission path characteristics from the FFT-processed signal (denoted as Y), and provisional equalization section 4002 divides the signal after FFT by the transmission path characteristics. Preliminary estimation (represented as X to (s), where s represents the current symbol number).
- the transmission line characteristic primary differential calculation section 4003 calculates the difference between the transmission line characteristic of the symbol before and after the current symbol for each carrier by Equation 1 from the estimated transmission line characteristic. Calculates the first derivative of the characteristic H (s) (denoted as ⁇ '(s)) and outputs it to the multiplier 4004.
- Ts indicates the OFDM symbol length.
- the multiplication unit 4004 calculates the ICI component K (s) by using the signal X to (s) after the quasi-equalization, the first-order differential value H ′ (s) of the transmission path characteristic, and the constant matrix S. Estimated by the calculation of Equation 2.
- the subtraction unit 1005 removes the ICI component estimated using Equation 2 from the signal Y after FFT by subtraction.
- Non-Patent Document 1 ARIB STD-B31
- Non-Patent Document 2 IEEE Std 802. 11a—1999
- Non-Patent Document 3 Karsten Schmidt et al., “Low Complexity Inter—Carrier Information Compensation for Mobile Reception of DVB—H” 9th International OFDM -Workshop 2004, Dresden. (P72-76, Fig. 4) Patent Document 1: Special Table 2004— 519900
- the transmission path characteristics exhibit frequency selectivity in a multipath fading environment, and a dip occurs in the reception band.
- a certain carrier has a relatively low level compared to other carriers and contains a lot of noise components, or when interference waves are mixed in a specific carrier, the temporary carrier data and transmission path estimated by that carrier An error occurs in the estimation of fluctuation, and as a result, an error occurs in the calculation of the interference component given to other carriers.
- the present invention provides a carrier capable of accurately estimating and removing an ICI component even in a multipath fading environment, even when the transmission path characteristics exhibit frequency selectivity or when interference waves are mixed. It is an object of the present invention to provide an inter-cell interference cancellation device. Means for solving the problem
- the present invention provides an inter-carrier interference removal that removes an inter-carrier interference component from a multi-carrier signal including a plurality of carrier signals exhibiting frequency response characteristics that vary depending on the state of a transmission path.
- An apparatus an acquisition unit that acquires a multicarrier signal, a reliability calculation unit that calculates reliability of each carrier signal based on a frequency response characteristic related to each carrier, and an equalization unit that equalizes each carrier signal
- a weighting unit that weights each carrier signal after equalization with the reliability related to each carrier signal before equalization, a variation amount of each frequency response characteristic related to each carrier signal before equalization, and weighting
- An inter-carrier interference removal unit that calculates an inter-carrier interference component based on each equalized carrier signal and removes it from each carrier signal before equalization.
- the carrier signal is used for calculating the intercarrier interference component after weighting the carrier signal with reliability based on the frequency response characteristics.
- the effects of multipath exhibit frequency selectivity, and even in a reception environment where the radio wave transmission path fluctuates at a high speed and inter-carrier interference occurs, the carrier is more accurate than before. It is possible to estimate and remove the inter-carrier interference component generated in the signal.
- FIG. 1 is a block diagram of an OFDM receiving apparatus including an intercarrier interference canceling apparatus according to Embodiment 1 of the present invention.
- FIG. 2 is a block diagram of an inter-carrier interference cancellation apparatus in Embodiment 1 of the present invention.
- FIG. 3 is a signal format of an OFDM signal shown in Non-Patent Document 1.
- FIG. 4 is a block diagram of a transmission path fluctuation estimation unit in the inter-carrier interference cancellation apparatus of Embodiment 1 of the present invention.
- FIG. 5 is a block diagram of an ICI cancellation calculation unit in the inter-carrier interference cancellation apparatus of Embodiment 1 of the present invention.
- FIG. 7 is a characteristic diagram in the case of a linear function as an example of the function f (x).
- FIG. 8 is a diagram schematically showing carriers weighted by reliability when the function is a linear function as an example of the function f (x).
- FIG. 9 is a characteristic diagram in the case of a step function as an example of the function f (x).
- FIG. 10 is a diagram schematically showing carriers weighted by reliability when the function is a step function as an example of the function f (x).
- FIG. 11 A characteristic diagram when the function f (X) is a linear function and the input is normalized by the average amplitude.
- FIG. 14 is a diagram schematically showing carriers of TMCC signal and AC signal in ISDB-T system.
- FIG. 15 is a block diagram when the reliability calculation unit and weighting unit according to the present invention are applied to the inter-carrier interference cancellation method shown in Non-Patent Document 3.
- FIG. 16 is a block diagram in which the receiver shown in Patent Document 1 is provided with a reliability calculation unit and a weighting unit according to the present invention.
- FIG. 17 is a block diagram of a receiving apparatus including the intercarrier interference canceling apparatus according to Embodiment 2 of the present invention.
- FIG. 18 is a detailed block diagram of the intercarrier interference canceling apparatus according to the third embodiment of the present invention.
- FIG. 19 is a block diagram showing a configuration of a reliability calculation unit in the intercarrier interference cancellation apparatus according to the fourth embodiment of the present invention.
- FIG. 20 Interference wave determination in the intercarrier interference canceling apparatus according to the fourth embodiment of the present invention It is a block diagram which shows the structure of a part.
- FIG. 21 is a block diagram when the intercarrier interference canceling apparatus of the present invention is applied to a diversity receiving apparatus.
- FIG. 22 is a block diagram of a demodulation unit for diversity reception including the inter-carrier interference cancellation apparatus according to the present embodiment.
- ⁇ 23 It is a block diagram showing the configuration of the intercarrier interference cancellation apparatus according to Embodiment 6 of the present invention.
- FIG. 24 is a schematic diagram showing a distance between a temporary carrier data signal point of each branch and a combined carrier data signal point.
- FIG. 25 is a schematic diagram showing a distance between a temporary carrier data signal point of each branch and a combined carrier data signal point in the case of branch power.
- FIG. 26 is a block diagram showing a configuration of an inter-carrier interference cancellation apparatus according to Embodiment 7 of the present invention.
- FIG. 27 is a block diagram of an intercarrier interference canceller including a block that performs clip processing on temporary carrier data.
- FIG. 28 is a schematic diagram showing clip processing unit force clipping amplitude.
- FIG. 30 is a block diagram of the reception processing unit in FIG. 29.
- FIG. 31 is a block diagram of a demodulator in FIG.
- FIG. 32 is a block diagram of a transmission path characteristic estimation unit in FIG. 31.
- FIG. 33 is a block diagram of an ICI component generation unit in FIG.
- FIG. 34 is a block diagram of a receiving apparatus having three stages of diversity combining in the first embodiment of the present invention.
- FIG. 35 is a block diagram of the reception processing unit in FIG. 34.
- FIG. 36 is a block diagram of the demodulator in FIG. 35.
- FIG. 37 is a block diagram of a receiving apparatus according to Embodiment 10 of the present invention.
- FIG. 38 is a block diagram of the reception processing unit in FIG. 37.
- FIG. 39 is a block diagram of the demodulator in FIG. 38.
- FIG. 40 is a block diagram showing an ICI removal unit of Non-Patent Document 3.
- FIG. 41 is a schematic diagram of an OFDM symbol.
- a receiving apparatus includes an inter-carrier interference canceling apparatus, and the inter-carrier interference canceling apparatus calculates the reliability of a carrier signal based on a transmission channel frequency characteristic of the carrier. Then, the ICI component is estimated more accurately using the reliability. Therefore, the receiving apparatus can more accurately remove the ICI component from the carrier signal, and the reception performance during high-speed movement in the OFDM scheme is improved.
- the receiving apparatus 1 receives an RF signal 702 that receives a radio wave of a desired channel via an antenna 701 and converts a radio frequency (RF) band signal into a baseband signal 720, and an analog signal.
- AZD unit 703 that converts to a digital signal
- symbol synchronization unit 704 that performs OFDM symbol synchronization processing
- guard removal unit 705 that removes the guard interval included in the OFDM symbol
- time domain OFDM signal to frequency domain carrier Estimate the frequency response characteristics of the transmission path from the frequency domain transforming unit 706 that converts the signal 110 into the signal
- the ICI removing unit 707 that estimates and removes the inter-carrier interference component from the carrier signal 110, and the carrier signal 117 from which the ICI component is removed.
- Configured to include a decoding section 710 to obtain a received bit data 728 from the carrier data 727 applies error correction processing.
- the receiving device 1 is a receiving device including an antenna, a tuner, a demodulation LSI, and the like.
- FFT Fast Fourier Transform
- FIG. 2 is a detailed block diagram of the intercarrier interference canceling apparatus 707.
- the inter-carrier interference canceling apparatus 707 includes a transmission path estimation unit 101, an equalization unit 1
- Transmission path estimation section 101 estimates the frequency response characteristic of the transmission path from carrier signal 110, and outputs transmission path frequency characteristic 111.
- the transmission path estimation unit 101 estimates a frequency response characteristic using a pilot carrier included in the carrier signal 110.
- FIG. 41 is a schematic diagram of an OFDM symbol. In the following, the symbol length of the OFDM symbol is T, the guard length is T, and the effective symbol length is T.
- Fig. 3 shows the format of the OFDM signal, in which the white circles indicate data carriers and the black circles indicate pilot carriers. S indicates a symbol number.
- the pilot carrier has the carrier data X (p is the carrier number of the pilot carrier) already on the receiving side.
- Equation 5 Y, which is actually received carrier data, is divided by Equation 5.
- the transmission path frequency characteristic for the data carrier located between them is calculated by interpolation.
- the transmission line frequency characteristic of the pilot carrier 151 is H (s-4) and the transmission line frequency characteristic of the pilot carrier 152 is H (s)
- the transmission line for each of the data carriers 153, 154, and 155 Frequency characteristics are H (s—l), H (s—2), and H (s—3).
- n is the carrier number.
- H (s-1), H (s-2), and H (s-3) are obtained by interpolating between H (s-4) and H (s).
- the frequency response characteristic obtained every third carrier in the carrier direction is interpolated in the carrier direction to estimate the transmission line frequency characteristic for all carriers including the data carrier.
- n + 3 n is interpolated in the carrier direction between the transmission channel frequency characteristic H (s) obtained by interpolation in the symbol direction for the data carrier 156 and the transmission channel frequency characteristic H (s) of the pilot carrier 152.
- the transmission line frequency characteristic H (n + 1 s) of the data carrier 157 and the transmission line frequency characteristic H (s) of the data carrier 158 are obtained.
- Equalization section 102 equalizes carrier signal Y (s) by the division shown in Equation 6 based on transmission channel frequency characteristic H (s), and estimates temporary carrier data X to (s) .
- X ⁇ (s) Y (s) / H (s) (Equation 6)
- the channel fluctuation estimation unit 105 calculates the channel frequency characteristic fluctuation amount H ′ (s) (hereinafter referred to as the channel fluctuation characteristic) generated before and after the symbol s from which ICI is removed, from the channel frequency characteristic H ( To do.
- the channel fluctuation estimation unit 105 delays the OFDM symbol length T as shown in FIG.
- the channel fluctuation estimation unit 105 calculates the channel fluctuation amount using the channel frequency characteristic H (s + 1) in the input carrier n and H (s-1) delayed by two symbol delay units. In part 901, the calculation based on Equation 7 is performed to estimate the channel fluctuation characteristics H and (s) in the sth symbol.
- the reliability calculation unit 103 calculates the reliability W (s) for the temporary carrier data X to (s).
- the reliability W (s) in the carrier n is calculated for each carrier based on the transmission path frequency characteristic H (s), and the relationship is associated with a predetermined function f (described later) (Equation 8).
- [z] indicates the amplitude of the vector z.
- the weighting unit 104 weights the temporary data symbol X to (s) by multiplication with the weight W (s) calculated by the reliability calculation unit 103.
- the ICI component estimation unit 106 multiplies the leak matrix S, the channel variation characteristic H ′ (s), and the weighted temporary carrier data X ′ (s) by multiplying the ICI component.
- Estimate K (s) the weighted temporary carrier data X ′ (s) by multiplying the ICI component.
- K (s) ⁇ ⁇ ⁇ '(s) -W (s) -X ⁇ (s)
- K (s), S, H, (s), W (s), and X to (s) are represented by matrices shown in Equations 11 to 15, respectively.
- T indicates transposition.
- the ICI removal calculation unit 107 removes the ICI component by subtracting the estimated ICI component K (s) from the input carrier signal Y n (s).
- the ICI removal calculation unit 107 is realized by a subtraction circuit 1000 as shown in FIG.
- the inter-carrier interference cancellation apparatus in Embodiment 1 of the present invention is
- a reliability calculation unit that calculates the reliability based on the transmission path frequency characteristics, and a weighting unit.
- intercarrier interference canceling apparatus 707 The operation of the intercarrier interference canceling apparatus 707 will be described in detail.
- the intercarrier interference cancellation apparatus 707 estimates temporary carrier data necessary for estimating the ICI component. Therefore, the transmission path estimation unit 101 estimates the transmission path frequency characteristic H (s), The equalization unit 102 equalizes the carrier signal Y (s) using H (s) to obtain temporary data symbols X to (s). A known pilot carrier at the receiving side shown in FIG. 3 is used for channel estimation.
- the levels are relatively different among the carriers, and a specific carrier (for example, carrier 161, carrier 162, for example). ) Carrier level is low.
- FIG. 6 is a diagram schematically showing how the carrier signal exhibits frequency selectivity.
- Equation 6 For the channel frequency characteristics H (s) in the n-th carrier, abs [H (s)] is the amplitude of each carrier signal itself, and if the amplitude of H (s) is small, it approaches the noise level. As a result, the equalization by Equation 6 increases the possibility of erroneous estimation of temporary data symbols X to (s). As a result, the estimation of the interference with other carriers is wrong. Also, if the amount of interference (leakage) is calculated using incorrect carrier data, ICI will be generated. Therefore, if there is a possibility that the carrier data is estimated incorrectly, that is, for carrier data of an unreliable carrier, if the contribution to the estimation of the ICI component is reduced, the estimation accuracy of the ICI component is improved. Can be improved.
- the temporary carrier data X ′ (s) necessary for the estimation of the ICI component is weighted according to the reliability of the carrier, and the estimation of the ICI component is performed. Improves reliability.
- the reliability calculation unit 103 calculates the reliability W (s) for the temporary data symbol: T (s) based on the transmission path frequency characteristic H (s).
- the reliability (weight) W (s) of a certain carrier n is expressed by a function f (X) having abs [H (s)] as input x, as shown in Equation 16.
- weighting section 104 multiplies provisional data symbol X ⁇ (s) by reliability W (s).
- the transmission path fluctuation estimation unit 105 removes the ICI component from the transmission path frequency characteristics H (s + 1) and H (s-1) before and after the OFDM symbol of the s symbol.
- the fluctuation H ′ (s) is calculated, and the ICI component estimation unit 106 estimates the ICI component K (s) by the calculation shown in Equation 10.
- ICI removal operation unit 107 is removed by subtracting the ICI component K n estimated from the carrier signal Y ⁇ n (s) (s) .
- the transmission path estimation section 708 and the equalization section 709 of the next stage of the ICI removal section 707 perform again the transmission path estimation and the equalization processing based on the carrier signal Y to (s) from which the ICI component is removed.
- the decoding unit 710 performs the error correction process and obtains the received bit data.
- Equation 17 when the amplitude abs [H] of the carrier signal takes a value of 1) ⁇ force 1, reliability is associated with a linear function proportional to the amplitude of the carrier signal, and ( ⁇ -1) If it is smaller than ⁇ , the reliability is zero (see Fig. 7).
- FIG. 7 is a characteristic diagram in the case of a linear function as an example of the function f (X).
- FIG. 8 is a diagram schematically illustrating carriers weighted by reliability when the function f (X) is a linear function as an example.
- FIG. 9 is a characteristic diagram in the case of a step function as an example of the function f (X).
- FIG. 10 is a diagram schematically showing a carrier signal weighted by reliability when it is a step function as an example of the function f (X).
- the reliability is a value of 0.
- the reference force of the input of the function f (x) is the average amplitude of the carrier. You may do it.
- Figure 11 is a characteristic diagram when the function f (X) is a linear function and the input is normalized by the average amplitude.
- FIG. 12 is a diagram schematically showing weighting by a linear function when the average amplitude of the carrier is used as a reference.
- the calculation is performed using all carriers (carrier 0 to carrier (N—1)) (Equation 19), or a plurality of peripheral carriers of the carrier n (carrier (n—L )
- the force can also be calculated only from the carrier (n + L)) (Equation 20).
- FIG. 13 is a diagram schematically showing the average power when the average power is standardized with a value averaged by a plurality of carriers.
- the threshold value for making the reliability zero changes.
- Carriers receive more interference from nearby carriers than distant carriers, so the carrier-level relative relationship is more accurate based on the average power calculated around the carrier.
- the carrier reliability can be calculated more accurately.
- the input X of the function f (X) may be input as a square value (power) of the carrier amplitude.
- the input X is as shown in Equation 21.
- a logarithmic value of the input value may be input.
- Equation 24 is the logarithm of Equation 22.
- function f (X) As described above, regarding the input X of the function f (x), the case of the carrier amplitude value, the case of the square value of the amplitude (power), and the case where they are standardized by the average value of a plurality of carriers have been described.
- function f (X) As an example, a linear function (Equation 17) and a step function (Equation 18) that becomes 0 or 1 with a predetermined threshold as a boundary are shown. Anything that can reflect the reliability of the carrier in the calculation of the ICI component is not limited.
- the intercarrier interference cancellation apparatus calculates the reliability based on the reliability of the carrier (Equation 8), and calculates the ICI component using this (Equation 8). 10) Therefore, the reliability of ICI component estimation is improved.
- the carrier of the pilot carrier since the carrier data is known on the receiving side, the interference component can be correctly estimated as compared with the data carrier. Therefore, it is desirable that the pilot carrier is considered highly reliable and not weighted.
- TMCC Transmission Multiplexing Configuration Control
- AC auxiliary Channel
- FIG. 14 is a diagram schematically showing carriers of TMCC signals and AC signals in the ISDB-T system.
- TMCC and AC signals differential BPSK is used as the primary modulation! /, So the error rate is much lower than data carriers that use 64QAM as the primary modulation. Therefore, for TMCC signal and AC signal carriers, ICI components can be estimated using probable carrier data, so TMCC signal and AC signal carriers are considered highly reliable. It is desirable not to weight.
- K (s) ⁇ -W (s) ⁇ ⁇ '(s) -X ⁇ (s)... (Formula 26)
- the part that multiplies W (s) in the circuit block that constitutes the ICI component does not matter, and it is sufficient that the part has the same estimation result.
- the transmission path fluctuation estimation section uses, as an example, transmission path fluctuation characteristics H from symbol s + 1 and symbol s-1 adjacent to symbol s to symbol s.
- (S) is estimated The symbol number used for the calculation, which can be obtained from the symbol s + 2 and the symbol s ⁇ 2 adjacent to each other.
- FIG. 15 is a block diagram when the reliability calculation unit and the weighting unit according to the present invention are applied to the intercarrier interference cancellation method shown in Non-Patent Document 3.
- the inter-carrier interference component generated in the carrier can be estimated and removed more accurately. As a result, reception characteristics can be improved.
- the present invention is applied to the ICI removal method of the feedforward process in which the temporary symbol data is estimated and the ICI component is removed and then the equalization process is performed again.
- the present invention is applied to an ICI removal method for feedback processing.
- the inter-carrier interference cancellation apparatus calculates reliability based on the transmission channel frequency characteristic estimated by the reliability calculation unit, and weights this to the estimated value of carrier data. Is.
- the reliability of ICI component estimation can be improved, the ICI component can be removed more accurately and carrier data can be estimated, and as a result, the reception performance during high-speed movement of the OFDM system can be improved.
- inter-carrier interference cancellation apparatus 1200 according to Embodiment 2 will be described with reference to the drawings.
- the intercarrier interference canceller 1200 includes a subtraction unit 1102, a transmission path estimation unit 1103, an equalization unit 1104, a multiplication unit 1105, a leak matrix multiplication unit 1106, and a reliability calculation.
- a unit 1201 and a weighting unit 1202 are included.
- the inter-carrier interference cancellation apparatus 1200 is mounted inside an LSI.
- the subtractor 1102 acquires a carrier signal obtained by converting a time domain signal into a frequency domain signal by an FFT unit outside the inter-carrier elimination apparatus, and removes the ICI component estimated by the carrier signal power by subtraction.
- the transmission path estimation unit 1103 estimates the transmission path frequency characteristic H and the time derivative ( ⁇ (that is, the amount of time fluctuation of the transmission path)).
- the equalization unit 1104 equalizes the carrier signal 1113 using the transmission path frequency characteristic H, and outputs carrier data s ′ 1115.
- Reliability calculation section 1201 calculates carrier reliability 1210 according to equation 27 based on transmission path frequency characteristic 1 114 estimated by transmission path estimation section 1103.
- the weighting unit 1202 weights the estimated carrier data s "with W for each carrier. Attach.
- Multiplication section 1105 multiplies time derivative (T1116 and carrier data weighted by weighting section 1202), and leak matrix multiplication section 1106 multiplies leak matrix S to estimate ICI component 1118.
- the accuracy of the ICI component is improved by executing repeated calculation processing using feedback multiple times.
- Expression 28 represents the above processing as a mathematical expression, and the carrier data can be accurately estimated by the calculation represented by Expression 28.
- i is the number of operations.
- the output of the inter-carrier interference cancellation apparatus 1200 is carrier data, and the inter-carrier interference cancellation apparatus 1200 corresponds to the ICI cancellation unit 707 in FIG.
- a decoding unit 710 is connected to the subsequent stage without including the transmission path estimation unit and the equalization unit in the subsequent stage.
- intercarrier interference cancellation apparatus 1200 calculates reliability 1210 based on transmission channel frequency characteristic 1114 estimated by reliability calculation section 1201, and uses this as an estimated value of carrier data. Since 1115 is weighted, similarly, the reliability of ICI component estimation can be improved.
- carrier data can be estimated more accurately by removing ICI components, and as a result, reception performance during high-speed movement of the OFDM scheme can be improved.
- the present invention for estimating ICI components by weighting adjacent carriers based on carrier reliability is an ICI removal method. Focusing on the fact that the component depends on the carrier data of the peripheral carrier, it can be applied to a method of estimating the ICI component in consideration of leakage from multiple peripheral carriers.
- the detailed ICI removal method and circuit configuration are It doesn't matter.
- the third embodiment directly performs the inverse matrix operation.
- the present invention is applied when calculating carrier data from which ICI components are removed.
- ( ⁇ ) _1 indicates an inverse matrix operation.
- Equation 32 forces H and (s), which are variables that H (s), H, and (s) should be estimated, are calculated by Equation 7, and are estimated according to the carrier level. The reliability of the value is determined.
- the reliability W (s) determined based on H (s) is defined as shown in Equation 33, and the reliability of each carrier is defined with respect to H '(s). With appropriate weighting, the transmission line frequency characteristics including inter-carrier interference can be calculated accurately.
- the carrier data can be estimated with high accuracy by the calculation represented by Equation 34.
- inter-carrier interference canceling apparatus 1400 for estimating carrier data based on Equation 34 will be described.
- the intercarrier interference canceling apparatus 1400 includes a transmission channel estimation unit 101, a reliability calculation unit 103, a transmission channel fluctuation estimation unit 105, a transmission channel ICI characteristic estimation unit 1401, and an inverse matrix calculation unit. 1402, a transmission path ICI inverse characteristic multiplication unit 1403, and a weighting unit 1404.
- Weighting section 1404 weights H ′ (s) estimated by transmission path fluctuation estimation section 105 by the reliability W (s) calculated by reliability calculation section 103 and multiplies the resulting transmission path fluctuation characteristics. 1410 is output.
- the transmission path ICI characteristic estimator 1401 obtains the transmission path characteristics H (s) and the transmission path fluctuation characteristics H '(s) -diag (W ( s))) estimate the ICI characteristics K '(s) of the transmission line including the mutual interference characteristics of ICI.
- the inverse matrix calculation unit 1402 calculates an inverse matrix of the transmission path ICI characteristic K ′ (s), and calculates an inverse characteristic of the transmission path ICI characteristic 1411.
- Transmission path ICI inverse characteristic multiplying section 1403 multiplies carrier signal 110 by inverse characteristic 1412 of the transmission path ICI characteristic to estimate carrier data.
- the receiving apparatus including the intercarrier interference canceling apparatus 1400 is equalized with the transmission path estimation unit in the subsequent stage, similarly to the receiving apparatus shown in FIG. And the decoding unit is connected to the subsequent stage.
- the inter-carrier interference cancellation apparatus 1400 calculates the carrier reliability based on the transmission channel frequency characteristic H estimated by the transmission channel estimation unit 101, Since this is weighted to the transmission path fluctuation characteristic H ', transmission including ICI components The reliability of the estimation of the path frequency characteristics (here called the transmission path ICI characteristics) can be improved. Therefore, carrier data can be obtained by more accurately removing ICI components, and as a result, reception performance during high-speed movement of the OFDM scheme can be improved. (Embodiment 4)
- Interfering waves include NTSC (National Television System Committee) signals and CW (Continu- ous Waves) interference, which are terrestrial analog broadcast signals.
- NTSC National Television System Committee
- CW Continuous- ous Waves
- the video subcarrier and the main audio subcarrier are narrow-band jamming waves.
- FIG. 19 is a block diagram showing a configuration of reliability calculation section 2100 in the intercarrier interference cancellation apparatus according to the present embodiment.
- the reliability calculation unit 2100 includes a transmission path determination unit 2101, an interference wave determination unit 2 102, and a determination unit 2103.
- the transmission path determination unit 2101 performs the same function as the reliability calculation unit 103 of the first embodiment. That is, the transmission line frequency characteristic is input, and the reliability value is output as transmission line information with a predetermined function.
- An interference wave determination unit 2103 detects an interference wave for each carrier.
- FIG. 20 is a block diagram showing a configuration of jamming wave determination section 2103 in the intercarrier interference cancellation apparatus according to the present embodiment.
- the interference wave determination unit 2103 includes an amplitude square unit 2111, a symbol direction smoothing unit 2112, an intra-symbol smoothing unit 2113, a multiplication unit 2114, and a comparison unit 2115.
- the amplitude squaring unit 2111 squares the amplitude of the transmission path variation characteristic for each carrier, and outputs the variation characteristic amplitude square value to the symbol direction smoothing unit 2112.
- Symbol direction smoothing section 2112 smoothes the fluctuation characteristic amplitude square value for each carrier in the symbol direction, and outputs the result to intra-symbol smoothing section 2113 and comparison section 2115.
- the channel fluctuation characteristics are smoothed over 128 symbols, but the present invention is not limited to this.
- the intra-symbol smoothing unit 2113 calculates an average value of all carriers in the symbol with respect to the smoothed variation characteristic amplitude square value output from the symbol direction smoothing unit 2112, and outputs the average value to the multiplication unit 2114.
- Multiplier 2114 multiplies the signal smoothed in the symbol by a predetermined coefficient c and outputs the result to the comparator.
- the coefficient c is a force of 16 as an example, but is not limited to this.
- Comparison section 2115 compares the output of multiplication section 2114 with the fluctuation characteristic amplitude square value smoothed in the symbol direction for each carrier, and compares the comparison result
- the channel fluctuation characteristics at that carrier position will be the average of the channel fluctuation characteristics of all carriers. It is relatively larger than the value (output of the smoothing part in the symbol). For this reason, it can be determined that a carrier having a relatively large channel fluctuation characteristic H ′ with respect to the average value of the channel fluctuation characteristics of all carriers is disturbed.
- the smoothing in the symbol direction can improve the detection accuracy of the interference wave.
- the determination unit 2102 outputs a reliability value based on the transmission path information output by the transmission path determination unit 2101 and the interference wave information output by the interference wave determination unit.
- the product of transmission path information and interference signal information is output as reliability W as shown in the following equation.
- the intercarrier interference canceling apparatus of the present invention is applied to a receiving apparatus that performs diversity reception using a plurality of antennas.
- FIG. 21 is a block diagram showing an intercarrier interference canceling apparatus according to the present embodiment.
- the transmission path frequency characteristic output from the transmission path estimation unit 101 and the provisional carrier data output from the equalization unit 102 are output to the outside of the intercarrier interference canceller, and the output of the reliability calculation unit 103 is transmitted to the transmission path fluctuation estimation unit 105.
- the output is configured to be weighted.
- the input of the ICI component estimation unit 106 is carrier data obtained by branch synthesis described later.
- FIG. 22 shows a block diagram of receiving apparatus 2250 for diversity reception including intercarrier interference canceling apparatus 2201 according to the present embodiment.
- Inter-carrier interference canceling apparatus 2201 corresponds to ICI removing section 2663 and ICI removing section 2664 in the receiving apparatus.
- Receiving apparatus 2250 includes a plurality of demodulating units 2251 and 2252 and a synthesizing unit 2253 provided for each branch.
- One demodulation unit 2251 includes an ICI removal unit 2263, a transmission path estimation unit 2265, and an equalization unit 2267.
- the demodulation unit 2252 includes an ICI removal unit 2264, a transmission path estimation unit 2266, and an equalization unit 22 68.
- the combining unit 2253 includes carrier combining units 2281 and 2284, a combined carrier weighting unit 2282, and a combined carrier reliability calculating unit 2283.
- a demodulation system including a demodulation unit for diversity reception includes a branch or a system.
- the reception apparatus according to the present embodiment includes two branches: a branch including a demodulation unit 2251 and a branch including a demodulation unit 2252.
- Carriage combining units 2281 and 2284 combine carrier data output from the demodulation units (2251 and 2252) of each branch for each carrier.
- the maximum ratio synthesis MR The case where C: Maximum Ratio Combining
- the carrier synthesizing unit 228 1 performs the following calculation.
- X n (s, b) and H n (s, b) indicate carrier data and transmission path frequency characteristics for the n-th carrier in the b-th system of the s-th symbol, respectively.
- combined carrier reliability calculation section 2283 calculates a reliability value (combined carrier reliability value) for combined carrier data 2315 for each carrier, and combined carrier weighting section 2282 includes combined carrier data 2315. Are weighted by the combined carrier reliability value.
- ICI removal units 2263 and 2264 of the demodulation unit will be described in detail.
- the fluctuation component H ′ (s, b) is obtained from H (s + 1) and H (s 1) of the transmission path estimation result.
- the fluctuation is obtained from the adjacent symbols of the s ⁇ 1 and s + 1 symbols as shown in the following equation.
- H, (s, b) ⁇ H (s + l, b) -H (s-1, b) ⁇ / (2-Ts)
- this H ′ is weighted according to reliability.
- weighting based on H (s, b) is performed.
- reliability is calculated and weighted for the combined carrier data 2315, and the ICI component is estimated and removed based on the weighted combined carrier data.
- the ICI component is estimated by using the weighted Xcl "(s) of the combined carrier data Xcl ⁇ as temporary carrier data. Therefore, the ICI for the nth carrier in the bth system of the sth symbol.
- the component estimate K (s, b) is
- the transmission path fluctuation characteristics estimated in each branch are weighted for each branch by the transmission path characteristics w (s, b) of that branch, and the temporary characteristics obtained by diversity combining are used. Data symbols are weighted by the combined power Pel (s).
- the combined carrier reliability calculation unit 2283 calculates the combined carrier reliability based on the transmission path frequency characteristic Hn. However, in the present embodiment, the temporary carrier data and the combined carrier data of each branch are calculated. Based on this, the composite carrier reliability is calculated. In this way, it is possible to effectively determine a carrier that has received an interfering wave, and to suppress erroneous ICI component estimation for the carrier.
- FIG. 23 shows demodulation sections 2251 and 2252 and a combining section 23 in the receiving apparatus according to this embodiment.
- 2 is a block diagram showing a configuration of an inter-carrier interference cancellation device 2301 including 02.
- the combined carrier reliability calculation unit 2311 in the combining unit 2302 calculates a combined carrier reliability value based on the carrier data 2312 and 2313 and the combined carrier data 2314 of each branch.
- Carriers not interfering with jamming waves are affected by noise in the transmission station power and the transmission path to the receiver. Concentrate around signal points.
- FIG. 24 is a schematic diagram showing the distance between the carrier data signal point of each branch and the combined carrier data signal point.
- the distance between the carrier data X (s, b) and the combined carrier data Xcl (s) of each branch is L (s, b)
- the threshold is ⁇
- b is the branch number (be 1, 2). Indicates.
- LEN (s, b), which is a difference from (s, b), is evaluated as a threshold ⁇ .
- the threshold ⁇ is the intersymbol distance determined by the modulation method, and it is determined by the binary value whether or not the threshold is exceeded, so whether L (s, b) is smaller than the threshold ⁇ , that is, LEN (s, 1) , Determine the polarity of LEN (s, 2).
- LEN n is expressed by the following equation.
- multi-value determination may be performed by using the total distance (LEN (s, 1) + LEN (s, 2)). Further, the combined carrier reliability value may be calculated based on the result of hard decision between the signal point of the temporary carrier data and the signal point of the combined carrier data of each branch at a predetermined signal point.
- the reliability is determined according to the number of formulas that are satisfied.
- the reliability is determined according to the number of established formulas.
- the tentative carrier data signal point of each branch and the combined carrier data Interference signal can be detected based on the signal point of the data, and as a result, erroneous estimation of the ICI component can be suppressed for the carrier.
- the distance L between the carrier data X (s, b) of each branch and the combined carrier data Xcl (s) is the so-called Euclidean distance.
- the in-phase component (real part) And the orthogonal component (imaginary part) can also be evaluated in the same way by calculating the distance and calculating the sum as the distance L.
- the hardware circuit can be deleted.
- Re [x] is the in-phase component (real part) of the complex number X
- Im [x] is the quadrature component (imaginary part).
- the distance L n (s) may be evaluated by smoothing for a certain period (here, expressed as smooth distance: Fil [L n ]).
- the smoothness distance is an average value using information of several hundreds or thousands of symbols in the symbol direction and several carriers or tens of carriers in the carrier direction, or a value smoothed using an IIR filter. Is used.
- the difference between the average distance and the distance L (s) in a certain symbol may be evaluated using a value based on the average distance Fil [L] as the threshold ⁇ .
- the threshold ⁇ may be set to an integer multiple or an singular multiple of the average value obtained only by the average value of the distance L as the threshold ⁇ . This makes it possible to set a threshold value according to the magnitude of the jamming signal. When the jamming signal is continuously mixed in a specific carrier for several symbols, the jamming signal is effectively mixed. Can be determined.
- the smoothing effect at the smoothing distance Fil [L] may be either one of the forces that increase the effect of the smoothing effect when performed in both the symbol direction and the carrier direction. (Embodiment 7)
- the combined carrier reliability calculation unit calculates the combined carrier reliability based only on temporary carrier data of each branch.
- FIG. 26 is a block diagram showing a configuration of intercarrier interference canceling apparatus 2401 including demodulation sections 2251 and 2252 and combining section 2402 in the receiving apparatus according to the present embodiment.
- the combined carrier reliability calculation unit 2411 in the combining unit 2402 calculates a combined carrier reliability value based only on the temporary carrier data 2412 and 2413 of each branch.
- Temporary carrier data after equalization used for ICI removal contains an error due to noise and interference wave mixing.
- carrier data is modulated with transmission data and has a predetermined signal point arrangement. Is.
- FIG. 27 is a block diagram of an intercarrier interference canceller including a block that performs clip processing on temporary carrier data.
- Clip processing section 2401 performs clip processing on the weighted carrier data and outputs the result to ICI component estimation section 106.
- Clip processing section 2401 performs clip processing with a predetermined amplitude as described below. As an example, the case where the in-phase component and the quadrature component of the carrier data are clipped with the amplitude of the pilot carrier is shown.
- FIG. 28 is a schematic diagram showing the amplitude to be clipped by the clip processing unit 2401. Black circles indicate the possible signal point arrangements for 64QAM. The in-phase and quadrature components have a maximum amplitude of 1. A white circle indicates the position of the pilot carrier. [0120] The pilot carrier is located at ⁇ 4Z3 on the in-phase component.
- Temporary carrier data is originally modulated and can take a predetermined signal point (the position of the black circle in Fig. 33), but it has a large amplitude away from the predetermined signal point due to the influence of noise and interference waves. May take.
- the in-phase axis exceeds 3Z4 and the orthogonal axis exceeds ⁇ 3 Z4.
- the in-phase axis component is 4Z3 and the in-phase axis component is ⁇ It shows how it is clipped to 4Z3.
- the force indicating the case of clipping at the amplitude level of the pilot carrier with respect to the clip level for the carrier data is not limited to this.
- FIG. 29 is a block diagram showing a diversity receiving apparatus according to the present embodiment.
- the receiving apparatus includes antennas 3001 and 3101, RF units 3002 and 3102 that select a received signal of a desired reception channel, reception processing units 3021 and 3121 that perform demodulation processing, and a first combining unit 3011.
- the decoding unit 3004 decodes the compressed signal, and the display unit 3005 outputs the video and audio decoded by the decoding unit 3004.
- FIG. 30 is a block diagram showing the configuration of the reception processing unit 3021.
- the configuration of the reception processing unit 3121 is the same as that of the reception processing unit 3021 and only the difference that the input signal is the output of the RF unit 3102 is omitted.
- the reception processing unit 3021 includes an AZD unit 3031, an orthogonal demodulation unit 3032, an FFT unit 3033, a symbol synchronization unit 3034, and a demodulation unit 3041.
- the AZD unit 3031 converts the output of the RF unit 3002 from an analog signal to a digital signal.
- the orthogonal demodulation unit 3032 converts the digital signal, which is the result of conversion by the AZD unit 3031, into a complex baseband signal by performing orthogonal demodulation, and converts the FFT unit 3033 and Output to symbol synchronizer 3034.
- Symbol synchronization section 3034 synchronizes the OFDM symbol period and outputs a symbol position information signal to FFT section 3033.
- the FFT unit 3033 Based on the symbol position information signal, the FFT unit 3033 performs Fourier transform on the orthogonal demodulated signal, converts it to a frequency domain signal, and outputs the signal to the demodulator 3041.
- FIG. 31 shows a block diagram of the configuration of the demodulator 3041.
- the demodulator 3041 includes a first received signal demodulator 3095 and a second received signal demodulator 3096.
- the first received signal demodulator 3095 includes a first transmission path estimator 3051 and a first equalizer 3052
- the second received signal demodulator 3096 includes an ICI component generator 3053.
- a subtracting unit 3054, a second transmission path estimating unit 3056, and a second equalizing unit 3055 are included.
- the configuration of the first transmission path estimation unit 3051 includes an SP generation unit 3061 that generates an SP (Scattered Pilot) that is a known signal, and an SP extraction unit 3062 that extracts an SP signal from the input signal. And a division unit 3063 and an interpolation unit 3064.
- the second transmission path estimation unit 3056 also includes the same components as the first transmission path estimation unit 3051.
- the SP signal is a reference signal, which is a signal inserted in the transmission signal in the transmission system of digital terrestrial television broadcasting or the like, and is the same as the pilot symbol used in the description of the above embodiment. Is.
- the SP signal is extracted from the signal after the FFT by the SP extraction unit 3062, and is divided by the division unit 3063 by the known signal generated by the SP generation unit 3061, thereby calculating the transmission path characteristic of the SP signal.
- interpolation processing is performed by the interpolation unit 3064 to calculate the transmission path characteristics of signals other than the SP signal.
- the first equalization unit 3052 estimates the transmission signal by dividing the signal after FFT by the calculated transmission path characteristic, and outputs the signal after provisional equalization to the first synthesis unit 3011 in FIG. .
- the transmission path characteristics calculated by the first transmission path estimation unit 3051 are also output to the first synthesis unit 3011.
- the first combining unit 3011 uses the respective transmission path characteristics output from the reception processing units 3021 and 3121 to diversity combine the signals after provisional equalization.
- Diversity synthesis is performed by using XI to (s, 1) for the signal after provisional equalization of the reception processing unit 3021, HI (s, 1) for the transmission path characteristics, and XI for the signal after provisional equalization of the reception processing unit 3121.
- ⁇ (S, 2) when the transmission line characteristic is expressed as HI (s, 2), it is synthesized using the maximum ratio composition as shown in Equation 57.
- the synthesis is not limited to that shown in Equation 57, and a known diversity synthesis method may be used.
- the signal synthesized by the first synthesis unit 3011 is output to the reception processing units 3021 and 3121.
- the output of the first combining unit 3011 may be output after the hard decision is made based on the transmission code point.
- the output signal of the first combining unit 3011 is input to the ICI component generation unit 3053, and the transmission path characteristics estimated by the first transmission path estimation unit 3051 are also input to the ICI component generation unit 3053.
- Various ICI component estimation methods have been proposed. Here, the ICI component estimation method described in Non-Patent Document 3 is used.
- ICI component generation section 3053 includes transmission path characteristic primary differential calculation section 3091 and multiplication section 3092.
- the transmission line characteristic primary derivative calculation unit 3091 inputs the transmission line characteristic, and for each carrier, calculates the first derivative from the transmission line characteristic of the symbol before and after the current symbol (symbol number p) using Equation 57. Calculate and output to multiplier 3092.
- Multiplier 3092 compares post-combination signal X ⁇ that is the output of first synthesis unit 3011, the output signal of transmission line characteristic primary derivative calculation unit 3091, and constant matrix S shown in Equation 3 and Equation 4. Performs multiplication. This calculation is as shown in Equation 2, and the ICI component is estimated and generated as described above.
- Non-Patent Document 3 As a method for generating an ICI component in the ICI component generation unit 3053, the method of Non-Patent Document 3 is used. Although it used, it is not limited to this, What is necessary is just to utilize a well-known thing.
- the estimated ICI component is subtracted by the subtractor 3054 from the signal power after the FFT to remove the IC I component.
- the output signal of the first synthesis unit 3011 is more reliable as a transmission signal due to the diversity effect than the output signal of the first equalization unit 3052, and as a result, the accuracy of ICI component generation is also improved. This makes it possible to remove ICI more correctly.
- second channel estimation unit 3056 estimates the channel characteristics after removing the ICI component.
- the transmission signal is estimated again by performing division using the transmission path characteristics estimated from the output of the subtraction unit 3054.
- the estimation accuracy is higher as a transmission signal than the output signal of the first equalization unit 3052.
- the improved output signal of the second equalization unit 3055 and the transmission path characteristic estimated by the second transmission path estimation unit 3056 are output to the second combining unit 3012.
- the second combining unit 3012 performs diversity combining of the respective second equalized signals using the transmission path characteristics of the signals after the ICI removal output from the reception processing units 3021 and 3121.
- the signal after the second equalization of the reception processing unit 3021 is X2 to (s, 1)
- the transmission path characteristic of the signal after ICI removal is H2 (s, 1)
- the reception processing When the signal after the second equalization in part 3121 is represented as X2 to (s, 2) and the transmission path characteristic of the signal after ICI removal is represented as H2 (s, 2), the maximum Synthesize using ratio synthesis.
- Xc2 ⁇ (s) (I H2 (s, 1) I 2 ⁇ ⁇ 2 ⁇ (s, 1) +
- the synthesis is not limited to that shown in Equation 58, and a known diversity synthesis method may be used.
- the same maximum ratio combining is used for the first combining unit 3011 and the second combining unit 3012.
- the first synthesis unit 3011 synthesizes signals affected by ICI
- the second synthesis unit 3012 synthesizes signals with different characteristics.
- the first combining unit 3011 and the second combining unit 3012 may perform processing using different diversity combining.
- the first transmission path estimation unit 3051 and the second transmission path estimation unit 3056 are described as being the same, the first transmission path estimation unit 3051 has a signal that is affected by ICI.
- the second transmission path estimation unit 3056 estimates the transmission path characteristics and estimates the transmission path characteristics of the signal from which the ICI has been removed. Different estimation methods may be used for the 3051 and the second transmission path estimation unit 3052.
- the second transmission path estimation unit 3052 is not provided, and the second equalization and second diversity combining are performed using the transmission path characteristics estimated by the first transmission path estimation unit 3051. May be. However, by removing ICI, the signal and transmission path characteristics before ICI removal change to V, so equalization and diversity combining is more effective with the transmission path characteristics of the signal after ICI removal.
- the signal after ICI removal is diversity-combined by the second combining unit 3012, and is output to the error correcting unit 3003 for decoding and display.
- the output signal of the second combining unit 3012 is more likely to be an estimated transmission signal than the signals after the second equalization of the respective reception processing units 3021 and 3121 due to the diversity effect, and the reception performance Will improve.
- the final transmission signal estimation accuracy is improved.
- the robustness to the signal is enhanced, and stable and good reception is possible even when moving or in a weak electric field environment.
- the force with two stages of diversity combining is limited to this. Instead, a configuration with three or more stages may be used, and ICI may be removed in stages.
- Figure 34 shows the configuration of a diversity receiver with three stages of diversity combining.
- the signal characteristics of ICI-removed signal power are also estimated for transmission path characteristics, and are used for equalization and diversity synthesis.
- a program that performs at least a part of the receiving process may be used, or a receiving method that performs at least a part of the receiving process in the receiving apparatus may be used.
- reception process for realizing the present embodiment may be implemented! /, A reception device, a reception method, a reception circuit, or a program may be combined.
- FIG. 37 A diversity receiving apparatus according to Embodiment 10 of the present invention will be described using FIG. 37, FIG. 38, and FIG.
- the same components as those described above are denoted by the same reference numerals and description thereof is omitted.
- FIG. 37 shows a block diagram of the diversity receiver according to the present embodiment.
- FIG. 39 shows a block diagram of the demodulator 3045.
- the demodulation unit 3045 includes an ICI component generation unit 3083, a subtraction unit 3054, an equalization unit 3081, and a transmission path estimation unit 3082.
- the output signal of the FFT unit 3033 is input to the subtraction unit 3054, and the output of the ICI component generation unit 3083 is subtracted.
- the output of the ICI component generation unit 3083 is zero.
- the output signal of the subtraction unit 3054 is input to the equalization unit 3081 and the transmission path estimation unit 3082.
- the transmission path estimation unit 3082 estimates the transmission path characteristics and outputs the estimation result to the equalization unit 3081 and the synthesis unit 3015.
- Transmission path estimation section 3082 is first transmission path estimation section 3051 shown in the ninth embodiment.
- the equalization unit 3081 estimates the transmission signal by dividing the signal after ICI removal by the estimated transmission path characteristic, and outputs the equalized signal to the synthesis unit 3015.
- the demodulating unit 3125 has the same configuration as the demodulating unit 3025, and the description is omitted because only the difference that the input signal is not the output signal of the RF unit 3002 but the output signal of the RF unit 3102.
- transmission path characteristics and equalized signals are output from demodulation section 3025 and demodulation section 3125, respectively, and diversity combining is performed in combining section 3015 based on the transmission path characteristics.
- Equation 1 may be used as in the ninth embodiment, but is not limited thereto, and a known method may be used.
- the combined signal is input to ICI component generation section 3083 in demodulation sections 3025 and 3125.
- the output signal of the synthesis unit 3015 may be input with a hard decision regarding the code point.
- the ICI component generation unit 3083 generates and estimates the ICI component based on the transmission path characteristics and the output of the synthesis unit 3015, and divides the signal after the FFT by the subtractor.
- the ICI component generation unit 3083 is different from the transmission line characteristic primary differential calculation unit 3091 of the ICI component generation unit 3053 in FIG. .
- the combined signal in the last iteration of the iteration within the symbol interval is output to error correction section 3003 for error correction.
- the ICI-removed and diversity-combined signal is recursively used for ICI component generation in each demodulator, so that the ICI component estimation accuracy in each demodulator is improved and iteration is repeated. The effect of noise and ICI is reduced, and ICI removal can be performed effectively.
- the circuit scale can be reduced compared to the ninth embodiment. This enhances the immunity to the effects of ICI and noise, and enables stable and good reception even when moving or in a weak electric field environment.
- the present invention is not limited to this.
- the diversity configuration with two or more antennas may be used.
- the reception performance can be improved.
- each component of the receiving apparatus according to the tenth embodiment may be realized by an integrated circuit. At this time, each component may be individually chipped so as to include a part or all of them.
- a program for performing at least part of the reception processing in the reception apparatus of the present embodiment may be used.
- a reception method for performing at least part of reception processing in the reception apparatus of Embodiment 10 may be used. It can be realized using.
- any receiving apparatus, receiving method, receiving circuit, or program that performs part of the receiving process for realizing the present embodiment may be realized in combination.
- the AZD unit 3031 is described as being located immediately before the orthogonal demodulation unit 3032. However, the present invention is not limited to this, and the AZD unit 3031 may be included in the tuner. However, the present invention is not limited to this immediately after the demodulator 3032.
- Embodiment 9 to L0 the description has been given using the diversity configuration with two antennas.
- the present invention is not limited to this, and the diversity configuration with two or more antennas can be further increased by increasing the number of antennas and demodulation units. The reception performance can be improved.
- the present invention is not limited to a space or angle diversity configuration having two or more antennas, and frequency diversity and time diversity may be implemented with one antenna.
- a plurality of demodulation units may not be provided, and the function of the demodulation unit may be realized using a memory or multiple processing.
- the power described as the OFDM signal used in the digital terrestrial broadcast wave is not limited to this, and any multicarrier transmission may be used, and further, the configuration for removing ICI will be described.
- any interference cancellation technique may be applied as long as it can generate and remove the transmission signal force that estimates the interference component included in the received signal, and in that case, instead of the ICI component generation unit 3053.
- the carrier combining (maximum ratio combining) shown in the above embodiments is the transmission channel frequency characteristics H (s, 1) and H (s, 2) obtained by each demodulator. From the output signals X (s, 1) and X (s, 2) of the equalization unit,
- the equalization unit is omitted, and the carrier signals Y n (s, 1) and Y (s, 2) and the channel frequency characteristics H (s, 1), H ( s, 2)
- a synthesis may be applied. * Indicates a complex conjugate.
- a diversity receiving apparatus includes a plurality of carrier combining units and performs carrier combining a plurality of times.
- the carrier combiner 2281 is the first carrier combiner and the carrier combiner 2283 is the second carrier combiner
- the mth carrier combiner Assuming that the signal is Ym (s, b), the transmission channel frequency characteristic is Hm (s, b), and the combined carrier data is Xcm (s, b), Equation 61 is expanded as Become.
- Xcm (s) (Hm (s, 1) * -Ym (s, 1) + Hm (s, 2) * -Ym (s, 2)) / (
- the carrier synthesis method as described above is applied as described below in the carrier synthesis portion of the above-described embodiment.
- the equalization unit 102 and the equalization unit (not shown) included in the ICI removal unit 2264 are omitted, and the outputs of the FFT units 2261 and 2262 Based on the transmission path characteristics obtained by the ICI removing units 2263 and 2264, the carrier combining unit 2281 may calculate the combined signal using Equation 62.
- the equalizers 2267 and 2268 are omitted, and carrier synthesis is performed based on the output of the ICI removal calculation unit 107, the ICI removal calculation unit (not shown) included in the ICI removal unit 2264, and the output of the transmission path estimation units 2265 and 2266.
- the composite signal may be calculated using Equation 62.
- Embodiment 9 shown in FIGS. 29, 30 and 31 the first equalization unit 3052 and the first equalization unit (not shown) included in the reception processing unit 3121 are omitted, and the FFT From the output of the FFT unit (not shown) included in the unit 3033 and the reception processing unit 3121 and the output of the first transmission path estimation unit (not shown) included in the first transmission path estimation unit 3051 and the reception processing unit 3121, In the first synthesis unit 3011, the composite signal may be calculated using Equation 62.
- the second equalization unit 3055 and the second equalization unit (not shown) included in the reception processing unit 3121 are omitted, and the subtraction unit (not shown) included in the subtraction unit 3054 and the reception processing unit 3121 is omitted.
- the second combining section 3012 uses the equation 62 A composite signal may be calculated.
- the third equalization unit (not shown) included in 3122 is omitted, the output of the subtraction unit (not shown) included in subtraction unit 3073 and reception processing unit 3122, and the third transmission path estimation unit 3075 and reception processing unit 3122 From the output of the second transmission path estimation unit (not shown,;) included in the third synthesis unit 3013,
- the composite signal may be calculated using Equation 62.
- the equalization unit 3081 and the equalization unit (not shown) included in the reception processing unit 3125 are omitted, and the subtraction unit 3054 and the reception processing unit are omitted.
- the synthesis unit 3015 May be used to calculate the composite signal.
- the conversion between the time domain and the frequency domain shows the OFDM signal based on the FFT and the demodulation processing related thereto, but a plurality of carriers are multiplexed on the frequency axis.
- it may be a multicarrier signal using wavelet transform, cosine transform, Hadamard transform, or the like.
- a system LSI is an ultra-multifunctional LSI manufactured by integrating multiple components on a single chip. Further, the plurality of components may be individually formed as one chip, or may be integrated into one chip so as to include a part or all of them.
- the name used here is LSI, but it may also be called IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.
- the method of circuit integration is not limited to LSI's, and implementation using dedicated circuitry or general purpose processors is also possible. It is also possible to use an FPGA (Field Programmable Gate Array) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connection and settings of circuit cells inside the LSI.
- FPGA Field Programmable Gate Array
- the above receiver and inter-carrier interference canceller are specifically a computer system that also includes power such as a microprocessor, ROM, RAM, hard disk unit, display unit, keyboard, and mouse. May be.
- a computer program is stored in the RAM or the hard disk unit.
- the microprocessor operates according to the computer program, each device becomes its function. Achieve performance.
- the computer program is configured by combining a plurality of instruction codes indicating instructions to the computer in order to achieve a predetermined function.
- a part or all of the components constituting each of the above devices may be configured as an IC card or a single module force that can be attached to and detached from each device.
- the IC card or the module is a computer system including a microprocessor, ROM, RAM, and the like.
- the IC card or the module may include the super multifunctional LSI described above.
- the IC card or the module achieves its function by the microprocessor operating according to the computer program. This IC card or module may be tamper resistant! /.
- the present invention may be the method described above. Further, the present invention may be a computer program that realizes these methods by a computer, or may be a digital signal that also has the computer program power.
- the present invention also provides a computer-readable recording medium such as a flexible disk, hard disk, CD-ROM, MO, DVD, DVD-ROM, DVD-RAM, BD (Blu-ray). It may be recorded on a disc) or semiconductor memory. Further, the present invention may be the computer program or the digital signal recorded on these recording media.
- a computer-readable recording medium such as a flexible disk, hard disk, CD-ROM, MO, DVD, DVD-ROM, DVD-RAM, BD (Blu-ray). It may be recorded on a disc) or semiconductor memory. Further, the present invention may be the computer program or the digital signal recorded on these recording media.
- the inter-carrier interference canceling apparatus and the receiving apparatus using the same according to the present invention remove inter-carrier interference caused by Doppler shift included in the multi-carrier signal, and therefore receive the multi-carrier signal while moving. In this case, the reception characteristics can be improved. Therefore, it is useful for in-vehicle receivers that are mounted on vehicles and trains that travel at high speed and receive terrestrial digital broadcasting and wireless LAN signals using the OFDM method while moving.
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- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Discrete Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Noise Elimination (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
- Radio Transmission System (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/090,735 US7991089B2 (en) | 2005-10-21 | 2006-10-20 | Inter-carrier interference removal device and reception device using the same |
CN2006800484361A CN101341677B (zh) | 2005-10-21 | 2006-10-20 | 载波间干涉去除装置及使用其的接收装置 |
JP2007541063A JP4938679B2 (ja) | 2005-10-21 | 2006-10-20 | キャリア間干渉除去装置及びこれを用いた受信装置 |
EP06812091.4A EP1940062B1 (en) | 2005-10-21 | 2006-10-20 | Inter-carrier interference removal device and reception device using the same |
US13/086,659 US8170162B2 (en) | 2005-10-21 | 2011-04-14 | Inter-carrier interference removal device and reception device using the same |
Applications Claiming Priority (4)
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JP2005307820 | 2005-10-21 | ||
JP2005-307820 | 2005-10-21 | ||
JP2005-362511 | 2005-12-15 | ||
JP2005362511 | 2005-12-15 |
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US12/090,735 A-371-Of-International US7991089B2 (en) | 2005-10-21 | 2006-10-20 | Inter-carrier interference removal device and reception device using the same |
US13/086,659 Division US8170162B2 (en) | 2005-10-21 | 2011-04-14 | Inter-carrier interference removal device and reception device using the same |
Publications (1)
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WO2007046503A1 true WO2007046503A1 (ja) | 2007-04-26 |
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PCT/JP2006/320962 WO2007046503A1 (ja) | 2005-10-21 | 2006-10-20 | キャリア間干渉除去装置及びこれを用いた受信装置 |
Country Status (5)
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US (2) | US7991089B2 (ja) |
EP (1) | EP1940062B1 (ja) |
JP (2) | JP4938679B2 (ja) |
CN (1) | CN101341677B (ja) |
WO (1) | WO2007046503A1 (ja) |
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Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7830994B2 (en) * | 2006-10-18 | 2010-11-09 | Analog Devices, Inc. | Channel estimation system and method |
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US9240908B2 (en) | 2008-10-15 | 2016-01-19 | Stmicroelectronics, Inc. | Pilot pattern for observation scalar MIMO-OFDM |
US9338033B2 (en) | 2008-10-15 | 2016-05-10 | Stmicroelectronics, Inc. | Recovering data from a primary one of simultaneous signals, such as orthogonal-frequency-division-multiplexed (OFDM) signals, that include a same frequency |
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US9130788B2 (en) | 2008-10-15 | 2015-09-08 | Stmicroelectronics, Inc. | Determining a response of a rapidly varying OFDM communication channel using an observation scalar |
US9130789B2 (en) | 2008-10-15 | 2015-09-08 | Stmicroelectronics Asia Pacific Pte. Ltd. | Recovering data from a secondary one of simultaneous signals, such as orthogonal-frequency-division-multiplexed (OFDM) signals, that include a same frequency |
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US9148311B2 (en) | 2008-10-15 | 2015-09-29 | Stmicroelectronics, Inc. | Determining responses of rapidly varying MIMO-OFDM communication channels using observation scalars |
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Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003524338A (ja) * | 2000-02-22 | 2003-08-12 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | チャネル予測器を有するマルチチャネル受信機 |
JP2004172699A (ja) * | 2002-11-18 | 2004-06-17 | Matsushita Electric Ind Co Ltd | ダイバーシティ受信装置及びダイバーシティ受信方法 |
JP2004519900A (ja) | 2001-02-22 | 2004-07-02 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | 軽減された計算量リーク行列乗算部を備えるマルチキャリア伝送システム |
JP2005229466A (ja) * | 2004-02-16 | 2005-08-25 | Pioneer Electronic Corp | 受信装置及び受信方法 |
WO2006041980A2 (en) | 2004-10-07 | 2006-04-20 | Phoenix Solutions Co. | Plasma arc collimator design and construction |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6494391B2 (en) * | 2001-02-05 | 2002-12-17 | M.C.M. Environmental Technologies Ltd. | Apparatus for treating waste, particularly medical waste, to facilitate its disposition |
US7298785B2 (en) * | 2001-07-04 | 2007-11-20 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Multicarrier demodulation method and apparatus, and multicarrier modulation method and apparatus |
SG120921A1 (en) * | 2002-03-13 | 2006-04-26 | Ntt Docomo Inc | Mimo receiver and method of reception therefor |
EP1408625A3 (en) * | 2002-10-11 | 2006-09-06 | Matsushita Electric Industrial Co., Ltd. | Diversity receiver and diversity receiving method for FDM signals |
JP4298320B2 (ja) * | 2002-11-08 | 2009-07-15 | 富士通株式会社 | Ofdm伝送方式における受信装置 |
JP4121407B2 (ja) * | 2003-03-20 | 2008-07-23 | 富士通株式会社 | Ofdmシンボルを復調する受信機 |
JP4367276B2 (ja) | 2004-07-28 | 2009-11-18 | パナソニック株式会社 | ダイバーシティ型受信装置、ダイバーシティ型受信装置を用いた受信方法および受信プログラム、ダイバーシティ型受信装置を用いた受信プログラムを格納した記録媒体 |
JP4421416B2 (ja) * | 2004-08-04 | 2010-02-24 | 富士通株式会社 | Ofdm方式の受信装置 |
-
2006
- 2006-10-20 CN CN2006800484361A patent/CN101341677B/zh active Active
- 2006-10-20 EP EP06812091.4A patent/EP1940062B1/en active Active
- 2006-10-20 US US12/090,735 patent/US7991089B2/en active Active
- 2006-10-20 JP JP2007541063A patent/JP4938679B2/ja active Active
- 2006-10-20 WO PCT/JP2006/320962 patent/WO2007046503A1/ja active Application Filing
-
2011
- 2011-04-14 US US13/086,659 patent/US8170162B2/en active Active
- 2011-12-21 JP JP2011279882A patent/JP5524943B2/ja active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2003524338A (ja) * | 2000-02-22 | 2003-08-12 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | チャネル予測器を有するマルチチャネル受信機 |
JP2004519900A (ja) | 2001-02-22 | 2004-07-02 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | 軽減された計算量リーク行列乗算部を備えるマルチキャリア伝送システム |
JP2004172699A (ja) * | 2002-11-18 | 2004-06-17 | Matsushita Electric Ind Co Ltd | ダイバーシティ受信装置及びダイバーシティ受信方法 |
JP2005229466A (ja) * | 2004-02-16 | 2005-08-25 | Pioneer Electronic Corp | 受信装置及び受信方法 |
WO2006041980A2 (en) | 2004-10-07 | 2006-04-20 | Phoenix Solutions Co. | Plasma arc collimator design and construction |
Non-Patent Citations (3)
Title |
---|
KARSTEN SCHMIDT ET AL.: "Low Complexity Inter-Carrier Interference Compensation for Mobile Reception of DVB-H", 9TH INTERNATIONAL OFDM-WORKSHOP, 2004, pages 72 - 76 |
SCHMIDT K. ET AL.: "Low Complexity Inter-Carrier Interference Compensation for Mobile Reception of DVB-T", 9TH INTERNATIONAL OFDM-WORKSHOP 2004, September 2004 (2004-09-01), pages 72 - 76, XP003012043 * |
See also references of EP1940062A4 |
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Also Published As
Publication number | Publication date |
---|---|
EP1940062A1 (en) | 2008-07-02 |
US20110211630A1 (en) | 2011-09-01 |
JPWO2007046503A1 (ja) | 2009-04-23 |
US20090225913A1 (en) | 2009-09-10 |
JP2012109993A (ja) | 2012-06-07 |
EP1940062A4 (en) | 2014-09-03 |
CN101341677A (zh) | 2009-01-07 |
US7991089B2 (en) | 2011-08-02 |
EP1940062B1 (en) | 2016-09-07 |
JP5524943B2 (ja) | 2014-06-18 |
JP4938679B2 (ja) | 2012-05-23 |
CN101341677B (zh) | 2012-01-11 |
US8170162B2 (en) | 2012-05-01 |
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