JP2016021695A - Carrier wave reproduction device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent transmission capacity decrease at adding a pilot for improving phase noise tolerance, in a carrier wave reproduction using a pilot.SOLUTION: A pilot signal is configured with a main pilot and a sub pilot. A phase error of the main pilot is interpolated, a phase of input data is corrected based on a phase error output by the phase error interpolation, phase errors of the main and sub pilot are corrected, and the phase of the input data is corrected based on a phase error outputted by phase error interpolation of the main and sub pilot signals.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a carrier recovery apparatus, and more particularly to a carrier recovery apparatus that corrects the phase of input data using a pilot signal of input data including a pilot signal.

  In recent years, in the field of digital communication systems, quadrature amplitude modulation (QAM) and polyphase phase modulation (PSK) have been used to meet market demands for improving frequency band utilization efficiency and speeding up data communication. Digital modulation / demodulation such as Phase Shiftl Keying) is adopted. Although these methods use phase information for data identification, there is a problem that phase information deteriorates due to phase noise of a transceiver at the time of modulation / demodulation. A technique capable of compensating for the problem of deterioration of phase information due to phase noise is required.

  As a technique related to the present invention, Patent Document 1 discloses a carrier recovery apparatus having a pilot phase estimator 205, a non-pilot base phase estimator 250, an interpolator / controller 211, a symbol buffer 220, and a derotator 225. There is disclosure.

Special table 2008-521281

IEE Conf Publ (Inst Electr Eng) Volume 492, pages 256-260 Low-Complexity Iterative Carrier Phase and Symbol Timing Recovery Approach for Turbo-Codes System

In order to improve the phase noise tolerance of carrier wave reproduction, a method as described in Non-Patent Document 1 has been proposed. Although this method has an excellent phase correction capability, there is a problem that compensation is difficult when a burst error occurs between pilot signals, and a technique for this problem is required.
(Object of invention)
A typical object of the present invention is to provide a carrier recovery apparatus having a high phase compensation capability.

According to the first aspect of the present invention, the phase error of the first pilot signal of the input data including the first pilot signal and the second pilot signal inserted between the first pilot signals is interpolated. A first interpolation filter to perform;
A first phase rotator that corrects the phase of the input data based on a phase error output from the first interpolation filter by interpolation of the phase error of the first pilot signal;
A second interpolation filter for interpolating the phase error of the first and second pilot signals output from the first phase rotator;
A second phase rotator for correcting the phase of the input data based on a phase error output by interpolation of phase errors of the first and second pilot signals from the second interpolation filter;
A carrier wave reproducing device is provided.

According to the second aspect of the present invention, the first error of the phase error of the first pilot signal of the input data including the first pilot signal and the second pilot signal inserted between the first pilot signals. An interpolation filter that performs a second interpolation of the phase error of the first and second pilot signals after performing the interpolation;
After the first phase correction of the input data based on the phase error output by the first interpolation of the phase error of the first pilot signal from the interpolation filter, the first pilot signal of the first and second pilot signals A phase rotator for performing a second phase correction of the input data based on a phase error output by a second interpolation of the phase error,
The interpolation filter and the phase rotator perform the first interpolation and the first phase correction, and then the interpolation filter and the phase rotator perform the first and the first phase correction after the first phase correction. There is provided a carrier recovery apparatus that performs the second interpolation of the second pilot signal and the second phase correction.

  According to the present invention, it is possible to improve the resistance to burst phase errors. Here, in the specification of the present application, the burst phase error means that the phase error increases instantaneously and cannot be followed by the first pilot signal, so that continuous data is erroneously determined as a phase-rotated signal point. It means phase error.

It is a block diagram which shows the structure of the carrier wave reproducing | regenerating apparatus which is the 1st Embodiment of this invention. FIG. 4 is a conceptual frame layout diagram of subpilots. It is a figure which shows the example of an interpolation filter operation | movement only of a main pilot. It is a figure which shows the operation example of the interpolation filter using a main / sub pilot. It is a figure explaining the error rate of a subpilot. It is a block diagram which shows the structure of the carrier wave reproducing | regenerating apparatus which is the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the carrier wave reproducing | regenerating apparatus which is the 3rd Embodiment of this invention. It is explanatory drawing of the carrier wave reproducing | regenerating apparatus which is the 4th Embodiment of this invention. It is explanatory drawing of the carrier wave reproducing | regenerating apparatus which is the 4th Embodiment of this invention. It is explanatory drawing of the carrier wave reproducing | regenerating apparatus which is the 5th Embodiment of this invention. It is a carrier wave reproducing | regenerating apparatus which is the 6th Embodiment of this invention. It is a block diagram which shows the carrier wave generator which produces | generates the flame | frame shown in FIG. It is a block diagram which shows the carrier wave generator which produces | generates the flame | frame shown in FIG.

  The carrier wave reproducing apparatus of the present invention takes two typical embodiments described below.

A carrier recovery apparatus according to an exemplary embodiment of the present invention includes a first pilot signal of input data including a first pilot signal and a second pilot signal inserted between the first pilot signal. A first interpolation filter that performs phase error interpolation, and a first phase rotator that corrects the phase based on a phase error output from the first interpolation filter by interpolation of the phase error of the first pilot signal. A first block comprising:
A second phase detector for calculating a shift error of the first and second pilot signals output from the first phase rotator; and a second phase detector for interpolating the phase errors of the first and second pilot signals. A second block comprising: an interpolation filter; and a second phase rotator for correcting a phase based on a phase error output by interpolation of the phase errors of the first and second pilot signals from the second interpolation filter And have.

  In the carrier wave recovery device of the above embodiment, the first block performs the process of correcting the phase using the first pilot signal, and then the second block uses the first and second pilot signals. Processing to correct the phase is performed.

A carrier recovery apparatus according to another exemplary embodiment of the present embodiment includes a first pilot signal of input data including a first pilot signal and a second pilot signal inserted between the first pilot signal. After performing the first phase error calculation, the phase detector for calculating the second phase error of the first and second pilot signals and the first interpolation of the phase error of the first pilot signal are performed. Later, based on an interpolation filter for performing a second interpolation of the phase error of the first and second pilot signals, and a phase error output by the first interpolation of the phase error of the first pilot signal from the interpolation filter. A phase rotator that performs a second phase correction based on the phase error output by the second interpolation of the phase error of the first and second pilot signals after performing the phase correction of 1.
The phase detector, the interpolation filter, and the phase rotator perform the first phase error calculation, the first interpolation, and the first phase correction, and then the phase rotator inputs the output to the phase detector; The phase detector, the interpolation filter, and the phase rotator perform the second phase error calculation, the second interpolation, and the second phase correction.

  In the carrier recovery device of the other embodiment, a phase detector, an interpolation filter, and a phase rotator constitute a single loop, and this loop is passed a plurality of times. That is, first, the phase detector, the interpolation filter, and the phase rotator perform the process of correcting the phase using the first pilot signal, and then, the first and second pilot signals output from the phase rotator are processed. The phase correction is performed by the phase detector, the interpolation filter, and the phase rotator which are the same components.

  Hereinafter, specific embodiments of the carrier wave reproducing apparatus according to the two typical embodiments will be described with reference to the drawings. The first pilot signal is a known pilot signal, which is called a main pilot, and the second pilot signal is an unknown pilot signal, which is called a sub-pilot. The known pilot signal is a predetermined signal known before reception of the carrier wave at the reception side having the carrier recovery device, and the unknown pilot signal is known before reception of the carrier wave at the reception side having the carrier recovery device. It is a signal that can be distinguished from transmission information (main signal).

(First embodiment)
FIG. 1 is a block diagram showing a configuration of a carrier recovery apparatus according to the first embodiment of the present invention. The carrier wave recovery apparatus according to the first embodiment performs a process of correcting the phase using the first pilot signal in the first block, and then performs the first and second processes in the second block. It is a device that performs processing for correcting a phase using a pilot signal.

  1 includes a data buffer 102 that temporarily stores input data 101, a preamble detector 109 that detects a preamble portion from the input data 101, phase detectors 110 and 111, and a main pilot interpolation filter 103. The phase rotators 104 and 107, the error correction circuit 105, and the main / sub-pilot interpolation filter 106 are constituent elements. Data is output from the phase rotator 107 as output data 108. The input data 101 temporarily stored in the data buffer 102 is input to the preamble detector 109, the phase detector 110, the phase rotator 104 and the phase rotator 107.

  The input data 101 is phase amplitude modulated digital data. The data buffer 102 is a buffer that temporarily stores the input data 101 for waiting for delay of the input data 101 and for repeating phase rotation correction.

  The preamble detector 109 has a function of detecting frame synchronization of the input data 101 by preamble / pilot correlation. Thereby, the insertion position of the main pilot is determined.

  The phase detector 110 calculates a phase error vector (I + jQ) at the main pilot position. The main pilot interpolation filter 103 obtains phase error information corresponding to all symbols by interpolating between the calculated phase errors.

  The phase rotator 104 has a function of correcting the phase based on the phase error output of the main pilot interpolation filter 103, and corrects the data stored in the data buffer 102.

  The error correction circuit 105 performs error correction of the subpilot part and outputs the main pilot and the subpilot after error correction. Although an error correction circuit is preferably provided, it may not be provided.

  The phase detector 111 calculates a phase error vector (I + jQ) of the main pilot and sub pilot positions from the main pilot and the error-corrected sub pilot.

  The main / sub pilot interpolation filter 106 obtains phase error information corresponding to all symbols by interpolating between the phase errors calculated by the phase detector 111.

  The phase rotator 107 has a function of correcting the phase based on the phase error output of the main / sub-pilot interpolation filter 106, and corrects the data stored in the data buffer 102.

  In this embodiment, the main pilot interpolation filter 103 and the phase rotator 104 are used to perform phase correction to the extent that the subpilot can be identified by the main pilot, and then the main / subpilot interpolation filter 106 and the phase rotator 107 perform the main correction. Phase correction by pilot and sub-pilot is performed.

  Next, the operation of this embodiment will be described. The following description will be given in 64QAM, but this embodiment is not limited to this modulation method.

  FIG. 2 is a frame layout diagram for explaining the present embodiment. The modulation multi-level number is described in 64QAM for explanation. In general, there is known preamble information to easily supplement a frame. The main pilot M and the subpilot S are alternately inserted in the frame configuration. Since the preamble and main pilot are necessary for initial acquisition, QPSK transmission of 2-bit information is performed. In this embodiment, a sub pilot is inserted between main pilots. The sub-pilot in the present embodiment is an information symbol with a reduced multi-value number. The sub-pilot has a lower multi-value number than transmission information (main signal), and the main pilot has a lower multi-value number than the sub-pilot. In FIG. 2, since the known information is 2 bits, the preamble, the main pilot is QPSK, the transmission information is 6 bits, the transmission information is 64 QAM, and the sub-pilot is 4 bits 16QAM with the lower 2 bits of the transmission information as non-information (fixed value) Yes.

  Burst phase errors that occur between main pilots are not represented in the main pilot phase estimation. If the main pilot is increased, it is possible to detect the burst phase error, but the transmission capacity is reduced. Therefore, instead of increasing the number of main pilots, sub pilots with a reduced multi-level number are handled as pilot signals, so that the tolerance to burst phase errors can be improved without reducing the transmission capacity. The reason is that if the pilot signal is known, it can be used as a reference signal for calculating the absolute phase error, and the sub-pilot whose multi-value number is lower than the transmission information (main signal) This is because there is a margin for N and the phase error, and it can be handled as a known signal.

  Improvement of the phase compensation capability not only copes with a transmission path with poor signal quality, but also reduces the accuracy of the reference signal for reproducing the carrier wave. Decreasing the accuracy of the reference signal generally contributes to cost reduction of the apparatus.

  FIG. 12 is a block diagram showing a carrier wave generation device for generating the frame shown in FIG. As shown in FIG. 12, preamble information 11 is input to the preamble codeword multiplexing unit 14, and transmission information 12 is encoded and input by the encoder 13. The preamble codeword multiplexing unit 14 inserts the same 6 bits as the lower 6 bits of the preamble information at the position of the main pilot, and sets the lower 2 bits as non-information (fixed value) at the position of the subpilot between the main pilots.

  A known pilot (2 bits) that is not related to the code word is inserted at the position of the preamble or the main pilot. The pilot information is generated in the preamble codeword multiplexing unit 14 or input together with the preamble information 11. The lower bits of the main pilot are fixed values. For example, when “1000” is set, the mapping is symmetric with respect to 2's complement. The lower order of the preamble information and the lower order of the main pilot do not have to be the same, but are the same when QPSK is used.

  In the sub-pilot, the lower 2 bits are non-information, and the transmission information is the upper 4 bits and the fixed value is the lower 2 bits.

  FIG. 3 illustrates the operation of the main pilot interpolation filter. A dotted line indicates a true phase error and needs to be corrected. When the phase error is estimated at the position of the main pilot M, it indicates that the steep movement of the phase error cannot be followed between the second M and the third M. An erroneous determination of a signal point occurs at this position and a burst error occurs. Since burst errors are difficult to remove by an error correction circuit, there is a high possibility that they will remain as bit errors.

  FIG. 4 illustrates the operation of the subpilot interpolation filter. This shows that when there is no subpilot recognition error, it is possible to follow a phase error that could not be followed by the main pilot interpolation filter.

  FIG. 5 shows the BER for each modulation multilevel. Thus, error correction of the subpilot part will be described. The 64QAM theoretical value 401 is a BER without error correction. The BER when this is error-corrected is 402. When no error correction is applied to 16QAM, which is one level below the modulation multi-value, 16QAM theoretical value 403 is obtained, indicating that an error occurs in the sub-pilot at the 64QAM operating point surrounded by a double circle. Such an error may not be preferable as a pilot. Therefore, by adding error correction to such an extent that it does not affect this operating point, for example, if a subpilot code having the characteristics of BER 404 after 16QAM error correction is selected, the subpilot will not be erroneous at the operating point.

  Accordingly, the type of code of the error correction circuit 105 is not limited, and any code may be used as long as the above operating point condition is satisfied.

  As described above, since a sub-pilot that can be used as a reference signal can be obtained in addition to the main pilot, the ability of phase correction is improved by the description of FIG.

(Second Embodiment)
FIG. 6 is a block diagram showing a configuration of a carrier recovery apparatus according to the second embodiment of the present invention. The carrier recovery apparatus of this embodiment shows the configuration of a carrier recovery apparatus in a wireless transmission application. In the carrier wave recovery apparatus of the second embodiment, a phase detector, an interpolation filter, a phase rotator, and an error correction circuit constitute one loop, and this loop is passed a plurality of times. Although an error correction circuit is preferably provided, it may not be provided.

  6 includes an orthogonal detector 503 that performs orthogonal axis separation on an IF (Intermediate Frequency) input signal 501, a local oscillator 502, an A / D converter 504 that converts the signal separated from the orthogonal axis into digital data, and digital data. A data buffer 506 for temporarily storing a preamble, a preamble detector 511 for detecting a preamble portion from digital data, a phase detector 512, a main / sub pilot interpolation filter 507, a phase rotator 508, and output data 510. The output error correction circuit 509 is a component.

  The difference from the first embodiment is that an orthogonal frequency detector 503 that performs orthogonal axis separation on an IF (Intermediate Frequency) input signal 501, an A / D converter 504 that converts the signal separated by orthogonal axes into digital data, and a clock recovery circuit 505. Is added, and the main pilot interpolation filter 103, the phase rotator 104, and the phase detector 111 are removed. Although the output of the A / D converter 504 is input to the clock recovery circuit 505, the output of the data buffer 505 may be input. Before the data buffer 102 of the first embodiment shown in FIG. 1, an orthogonal detector 503 that separates an IF (Intermediate Frequency) input signal 501 by orthogonal axes, and A / D conversion that converts the signals separated by orthogonal axes into digital data A clock 504 and a clock recovery circuit 505 may be provided.

  In the configuration of FIG. 1 showing the first embodiment, a phase detector 110, a main pilot interpolation filter 103, a phase rotator 104, an error correction circuit 105, a phase detector 111, a main / sub-pilot interpolation filter 106, a phase rotator 107 are connected in series. In contrast, in the present embodiment, the phase detector 512, the main / sub-pilot interpolation filter 507, the phase rotator 508, and the error correction circuit 509 form a loop, and initially the phase detector 512, the main / sub-interpolation filter 507, the phase rotator 508 corrects the phase of the input data using the main pilot, the error correction circuit 509 corrects the subpilot error, the output of the error correction circuit 509 is input to the phase detector 512, and the phase The detector 512, the main / sub interpolation filter 507, and the phase rotator 508 correct the phase of the input data using the main pilot and the subpilot, and output the output data 510 from the error correction circuit 509.

  Note that the quadrature detector 503 and the clock recovery circuit 505 can be digitally processed after the A / D converter 504.

  In this embodiment, the phase detector 512, the main / sub-pilot interpolation filter 507, the phase rotator 508, and the error correction circuit 509 form a loop. When the loop is passed twice, only the main pilot is used for the first time. The phase is corrected and the phase is corrected using the main pilot and sub-pilot (considered as known) at the second time. However, since it is conceivable that the sub-pilot is erroneous due to the trade-off between the assumed phase error and the pilot amount, the loop may be passed three or more times.

  In the present embodiment, as shown in FIG. 6, since a loop is formed including the error correction circuit 509, the error correction circuit 509 performs error correction of the subpilot portion and then passes through the error correction circuit 509. It will be. Basically, error correction is also performed for the second time. However, for example, due to the amount of processing, a method may be used such as “no error correction for the first time and error correction for the second time”. Further, a loop including the error correction circuit 509 may be passed three or more times. In the sixth embodiment to be described later, no error (≈no syndrome) is handled as a sub-pilot, but in this case, decoding the entire information portion increases the number of sub-pilots, so multiple error corrections are performed. It is desirable to do it once.

(Third embodiment)
FIG. 7 is a block diagram showing a configuration of a carrier recovery apparatus according to the third embodiment of the present invention. The same components as those shown in FIG. 6 are given the same reference numerals and the description thereof is omitted. In this embodiment, a deinterleave circuit 601 is added to the configuration of FIG. 6 showing the second embodiment in order to cope with a burst error. When deinterleaving is performed, errors are dispersed, so that the error correction circuit may be able to correct the errors, and the number of repetitions of the phase correction process is reduced. The deinterleave circuit 601 can be added before the error correction circuit 105 of FIG.

(Fourth embodiment)
8 and 9 are signal arrangement diagrams in the carrier wave reproducing apparatus according to the fourth embodiment of the present invention. One quadrant of the four quadrants is shown. The configuration of the transport reproduction apparatus of this embodiment is the same as the configuration of FIG. 1, FIG. 6, or FIG. Generally speaking, 16QAM and 64QAM are mappings in which transmission information is squarely arranged at regular intervals as shown in FIG. However, in the case of a sub-pilot application, there is a problem that a signal point with a low level is easily affected by thermal noise and it is difficult to extract a signal error. In order to improve it, it is possible to arrange subpilots at the transmission information arrangement positions shown in FIG. 8 as shown in FIG. In the description, 64 / 16QAM is used for explanation, but other modulation schemes can also perform mapping with the low signal level removed.

(Fifth embodiment)
FIG. 10 is an explanatory diagram of a carrier wave reproducing device according to the fifth embodiment of the present invention. Similar to the fourth embodiment, the configuration of FIG. 1, FIG. 6 or FIG. The subpilot indicated by S should have a lower required S / N than the information part. Therefore, the subpilot operation can be performed by increasing the subpilot coding rate and increasing the accuracy of the subpilot at the operating point. In addition, since the code word is different from the information part without changing the code, it has an interleaving effect in which errors are dispersed. Therefore, this alone has sufficient performance depending on the expected phase noise level.

  FIG. 13 is a block diagram showing a carrier wave generating device that generates the frame shown in FIG. 12 differs from the configuration shown in FIG. 12 in that the preamble codeword multiplexing unit 14 is a preamble codeword multiplexing unit 17, and the transmission information 15 for subpilot is transmitted via the subpilot encoder 16 to the preamble codeword multiplexing unit 17. This is the point that is input to. In the preamble codeword multiplexing unit 17, the preamble information 11 is input, the transmission information 12 is encoded and input by the encoder 13, and the subpilot transmission information 15 is transmitted through the subpilot encoder 16. Input to the codeword multiplexing unit 17. Then, the frame shown in FIG. 10 is created.

(Sixth embodiment)
FIG. 11 is an explanatory diagram of a carrier wave reproducing device according to the sixth embodiment of the present invention. Similar to the fourth embodiment, the configuration of FIG. 1, FIG. 6 or FIG. In this configuration, no special subpilot is inserted. When using LDPC or turbo code, syndromes can be obtained sequentially without checking all codewords. Since there is a high possibility that a place without a syndrome is a code word, it is used as a sub-pilot. This configuration is appropriate when the syndrome test block is fine, but it is susceptible to phase noise because the number of multivalues is not changed. When iterative phase correction is performed, the number of data that can be error-corrected gradually increases, so this method is suitable for iterative processing.

  The carrier wave generating device shown in FIG. 11 can use the carrier wave generating device shown in FIG.

  Although the embodiments of the present invention have been described above, some or all of the plurality of components constituting the carrier wave reproducing device shown in FIGS. 1, 6, and 7 may be configured by hardware or software. Or a combination of hardware and software. When configured by hardware, some or all of a plurality of components are integrated circuits such as LSI (Large Scale Integrated circuit), ASIC (Application Specific Integrated Circuit), gate array, FPGA (Field Programmable Gate Array), etc. (IC).

  Some or all of the functions of each unit can also be realized by a computer reading a program that realizes the function from a computer-readable recording medium such as a CD-ROM, DVD, or flash memory and executing it.

  For example, a computer as a packet aggregating device is configured with a storage unit such as a hard disk or ROM that stores programs, a display unit such as a liquid crystal display, a DRAM that stores data necessary for calculation, a CPU, and a bus that connects each unit. be able to. The operation of the components shown in FIG. 1, FIG. 6 or FIG. 7 (for example, phase detector, main / sub pilot and phase rotator) is described by a program, and this program is stored in a storage unit such as a ROM for calculation. The data analysis / management unit functions according to the present embodiment can be realized by a program by storing necessary information in the DRAM and causing the CPU to operate the program.

  Furthermore, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention described above.

  A part or all of the above embodiment can be described as the following supplementary notes, but is not limited to the following configuration.

(Appendix 1)
A first interpolation filter for interpolating a phase error of the first pilot signal of input data including a first pilot signal and a second pilot signal inserted between the first pilot signal;
A first phase rotator that corrects the phase of the input data based on a phase error output from the first interpolation filter by interpolation of the phase error of the first pilot signal;
A second interpolation filter for interpolating the phase error of the first and second pilot signals output from the first phase rotator;
A second phase rotator for correcting the phase of the input data based on a phase error output by interpolation of phase errors of the first and second pilot signals from the second interpolation filter;
A carrier wave reproducing apparatus comprising:

(Appendix 2)
After performing the first interpolation of the phase error of the first pilot signal of the input data including the first pilot signal and the second pilot signal inserted between the first pilot signal, the first and second An interpolation filter for performing a second interpolation of the phase error of the pilot signal of 2;
After the first phase correction of the input data based on the phase error output by the first interpolation of the phase error of the first pilot signal from the interpolation filter, the first pilot signal of the first and second pilot signals A phase rotator for performing a second phase correction of the input data based on a phase error output by a second interpolation of the phase error,
The interpolation filter and the phase rotator perform the first interpolation and the first phase correction, and then the interpolation filter and the phase rotator perform the first and the first phase correction after the first phase correction. 2. A carrier recovery apparatus that performs the second interpolation of the second pilot signal and the second phase correction.

(Appendix 3)
A first phase detector that calculates a phase error of the first pilot signal and outputs a phase error to the first interpolation filter; and the first and second phase rotators that are output from the first phase rotator. The carrier wave regeneration apparatus according to appendix 1, further comprising: a second phase detector that calculates a phase error of two pilot signals and outputs the phase error to the second interpolation filter.

(Appendix 4)
After calculating the phase error of the first pilot signal and outputting it to the interpolation filter, calculating the phase error of the first and second pilot signals output from the phase rotator and outputting to the interpolation filter The carrier wave reproducing device according to supplementary note 2, comprising a phase detector for performing

(Appendix 5)
5. The carrier recovery apparatus according to any one of appendices 1 to 4, further comprising a preamble detector that detects frame synchronization of the input data from the preamble signal of the input data.

(Appendix 6)
A data buffer for temporarily storing the input data, a reference oscillator and a quadrature detector for quadrature detection of the IF input, an analog signal is input from the quadrature detector, and a converted digital signal is output to the data buffer The carrier wave regeneration device according to appendix 2 or 4, further comprising: an A / D converter that performs a clock regeneration circuit that regenerates a clock based on an output from the phase rotator and outputs the clock to the A / D converter.

(Appendix 7)
7. The carrier recovery apparatus according to any one of appendices 1 to 6, wherein the second pilot signal has a multivalue lower than the multivalue of the main signal of the input data.

(Appendix 8)
The carrier wave regeneration device according to any one of appendices 1 to 6, wherein the second pilot signal has the same multi-value number as the main signal of the input data, but is a different code word.

(Appendix 9)
The carrier wave according to any one of appendices 1 to 6, wherein the second pilot signal is the same code word as the main signal of the input data and is treated as a second pilot signal depending on the presence or absence of a code syndrome Playback device.

(Appendix 10)
10. The carrier wave reproducing device according to any one of appendices 1, 3, and 5-9 having an error correction circuit after the first phase rotator.

(Appendix 11)
10. The carrier recovery apparatus according to any one of appendices 2, 4, and 5-9, having an error correction circuit after the phase rotator.

(Appendix 12)
The carrier wave reproducing device according to appendix 10 or 11, comprising a deinterleave circuit on the input side of the error correction circuit.

(Appendix 13)
In the carrier wave reproducing method of the carrier wave reproducing device for correcting the phase of the input data using the pilot signal of the input data including the pilot signal,
The pilot signal consists of a first pilot signal and a second pilot signal inserted between the first pilot signal,
The carrier wave reproducing device is
Interpolating the phase error of the first pilot signal;
Correcting the phase of the input data based on the phase error output by interpolation of the phase error of the first pilot signal;
Interpolating the phase error of the first and second pilot signals;
A carrier recovery method, wherein the phase of the input data is corrected based on a phase error output obtained by interpolation of phase errors of the first and second pilot signals.

(Appendix 14)
The carrier recovery apparatus interpolates the phase error of the first pilot signal after calculating the phase error of the first pilot signal, and further calculates the phase error of the first and second pilot signals. 14. The carrier wave recovery method according to supplementary note 13, wherein after performing the operation, interpolation of phase errors of the first and second pilot signals is performed.

(Appendix 15)
The carrier wave recovery device detects the frame synchronization of the input data from the preamble signal of the input data, detects the insertion position of the first pilot signal, and then interpolates the phase error of the first pilot signal. 15. A carrier wave reproduction method according to appendix 13 or 14.

(Appendix 16)
16. The carrier wave recovery method according to any one of appendices 13 to 15, wherein the second pilot signal has a multivalue lower than the multivalue number of the main signal of the input data.

(Appendix 17)
The carrier wave regeneration method according to any one of appendices 13 to 15, wherein the second pilot signal has the same multi-value number as the main signal of the input data, but is a different code word.

(Appendix 18)
18. The carrier wave recovery method according to any one of appendices 13 to 17, wherein the second pilot signal is the same code word as the main signal of the input data and is treated as an unknown pilot depending on the presence or absence of a code syndrome .

(Appendix 19)
A carrier wave recovery method for correcting an error of the second pilot signal after correcting a phase of the input data based on a phase error output by interpolation of a phase error of the first pilot signal.

(Appendix 20)
A computer as a carrier wave generator,
A first interpolation filter for interpolating a phase error of the first pilot signal of input data including a first pilot signal and a second pilot signal inserted between the first pilot signal;
A first phase rotator that corrects the phase of the input data based on a phase error output from the first interpolation filter by interpolation of the phase error of the first pilot signal;
A second interpolation filter for interpolating the phase error of the first and second pilot signals output from the first phase rotator;
A second phase rotator for correcting the phase of the input data based on a phase error output by interpolation of phase errors of the first and second pilot signals from the second interpolation filter;
Program to function as.

(Appendix 21)
A carrier wave generating device for generating a carrier wave to be transmitted to the carrier wave reproducing device according to appendix 8 or 10,
An encoder for encoding the main signal;
A main signal encoded by the encoder and preamble information; and a second pilot signal inserted between the main signal, the preamble information, the first pilot signal, and the first pilot signal. And a multiplexing unit that generates a transmission signal including the carrier signal.

(Appendix 22)
A carrier wave generation device that generates a carrier wave to be transmitted to the carrier wave reproduction device according to attachment 9, wherein
A first encoder for encoding a main signal;
A second encoder for encoding a second pilot signal;
Receiving preamble information, a main signal encoded from the first encoder, and a second pilot signal encoded by the second encoder, the main signal, the preamble information, the first And a multiplexing unit for generating a transmission signal including the encoded second pilot signal inserted between the first pilot signal and the first pilot signal.

  The present invention is applied to a carrier recovery apparatus that corrects the phase of input data using a pilot signal of input data including a pilot signal.

Reference Signs List 101 Digital data input 102 Data buffer 103 Main pilot interpolation filter 104 Phase rotator 105 Subpilot error correction circuit 106 Main / subpilot interpolation filter 107 Phase rotator 108 Data output 109 Preamble detector 110, 111 Phase detector 401 64QAM Error-free theoretical value 402 Characteristic example with 64QAM error correction 403 16QAM error-free theoretical value 404 Characteristic example with 16QAM error correction 501 IF input 502 Reference signal oscillator 503 Quadrature detector 504 A / D converter 505 clock Reproduction circuit 506 Data buffer 507 Main / sub pilot interpolation filter 508 Phase rotator 509 Error correction circuit 510 Data output 511 Preamble detector 512 Phase detection Vessel 601 de-interleaving

Claims (10)

A first interpolation filter for interpolating a phase error of the first pilot signal of input data including a first pilot signal and a second pilot signal inserted between the first pilot signal;
A first phase rotator that corrects the phase of the input data based on a phase error output from the first interpolation filter by interpolation of the phase error of the first pilot signal;
A second interpolation filter for interpolating the phase error of the first and second pilot signals output from the first phase rotator;
A second phase rotator for correcting the phase of the input data based on a phase error output by interpolation of phase errors of the first and second pilot signals from the second interpolation filter;
A carrier wave reproducing apparatus comprising: After performing the first interpolation of the phase error of the first pilot signal of the input data including the first pilot signal and the second pilot signal inserted between the first pilot signal, the first and second An interpolation filter for performing a second interpolation of the phase error of the pilot signal of 2;
After the first phase correction of the input data based on the phase error output by the first interpolation of the phase error of the first pilot signal from the interpolation filter, the first pilot signal of the first and second pilot signals A phase rotator for performing a second phase correction of the input data based on a phase error output by a second interpolation of the phase error,
The interpolation filter and the phase rotator perform the first interpolation and the first phase correction, and then the interpolation filter and the phase rotator perform the first and the first phase correction after the first phase correction. 2. A carrier recovery apparatus that performs the second interpolation of the second pilot signal and the second phase correction. A first phase detector that calculates a phase error of the first pilot signal and outputs a phase error to the first interpolation filter; and the first and second phase rotators that are output from the first phase rotator. 2. The carrier recovery device according to claim 1, further comprising: a second phase detector that calculates a phase error of two pilot signals and outputs the phase error to the second interpolation filter. After calculating the phase error of the first pilot signal and outputting it to the interpolation filter, calculating the phase error of the first and second pilot signals output from the phase rotator and outputting to the interpolation filter The carrier recovery device according to claim 2, further comprising a phase detector for performing the operation. 5. The carrier recovery device according to claim 1, further comprising a preamble detector that detects frame synchronization of the input data from the preamble signal of the input data. 6. A data buffer for temporarily storing the input data, a reference oscillator and a quadrature detector for quadrature detection of the IF input, an analog signal is input from the quadrature detector, and a converted digital signal is output to the data buffer 6. An A / D converter, and a clock recovery circuit that regenerates a clock based on an output from the A / D converter or the data buffer and outputs the clock to the A / D converter. The carrier recovery device according to any one of the above. The carrier wave recovery device according to any one of claims 1 to 6, further comprising an error correction circuit after the phase rotator or the first phase rotator. The carrier wave recovery device according to any one of claims 1 to 7, wherein the second pilot signal has a multivalue lower than a multivalue number of a main signal of the input data. 8. The carrier recovery apparatus according to claim 1, wherein the second pilot signal has the same multi-value number as the main signal of the input data, but is a different code word. The said 2nd pilot signal is the same codeword as the main signal of the said input data, It treats as an unknown pilot by the presence or absence of the code | symbol syndrome, The one of Claim 1 to 7 characterized by the above-mentioned. Carrier wave reproducing device.

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