JP4276490B2 - Interleave transmitter and interleave receiver - Google Patents

Description

The present invention also relates to the interleaving transmission apparatus and interleaving receiving equipment, about the interleaving transmission apparatus and interleaving reception equipment for transmitting and receiving data obtained in particular by performing the interleaving long period.

  Conventionally, a long-period interleave transmission technique is known as a technique for overcoming signal level attenuation due to rainfall during data transmission in broadcasting or the like (see, for example, Patent Document 1 and Non-Patent Document 1). Here, interleaving means rearranging data to be transmitted. FIG. 12 is a diagram for explaining the principle of a conventional long-period interleave transmission technique.

  In FIG. 12, a transmitting apparatus transmits data to which data to be transmitted is subjected to long-period interleaving, such as a 24-hour period, and error correction data (parity) is added, and a receiving apparatus transmits the received signal to the received signal. On the other hand, they are rearranged in the original order (deinterleaving) and error correction is performed. In general, data rearrangement when performing interleaving and deinterleaving is performed using a recording medium such as a hard disk.

  With this configuration, even if reception is not performed well due to rain and a part of the received data is lost, the missing part is dispersed by deinterleaving. When the missing data portion is dispersed, the data can be restored by using an error correction technique, so that the problem of rain attenuation can be solved or reduced.

  Here, the ratio of the time when correct data (after error correction) is received with respect to the transmission time is referred to as a service time ratio. The service time rate is one index for determining whether the broadcast service is good or bad. In order to achieve a high service time ratio in the long-period interleave transmission technology, transmission is generally performed with a modulation scheme having a low C / N (Carrier to Noise Ratio, hereinafter referred to as “required C / N”) necessary for transmission. . This is because if the required C / N is low, the rain margin becomes large, the proportion of data missing due to rain is small, and data can be restored even if the interleaving cycle (hereinafter simply referred to as “interleaving cycle”) is short. On the other hand, when transmission is performed using a modulation method with a high required C / N, the rain margin is small and a lot of missing data is generated. In this case, in order to disperse the missing data and restore the data satisfactorily, it is necessary to make the interleaving cycle long.

On the other hand, a TDD (Time Division Duplex) adaptive modulation transmission / reception apparatus configured as shown in FIG. 13 is also disclosed (see, for example, Patent Document 2). The TDD adaptive modulation / reception apparatus configured as shown in FIG. 13 performs error correction on a signal received by performing TDD communication, and calculates an error correction unit 6 that calculates a bit error rate, based on information on the bit error rate. A receiving apparatus unit B is provided that includes a channel quality estimation unit 7 that estimates a channel state at that time and designates a modulation scheme according to the channel state. The transmitter unit A of the TDD adaptive modulation scheme transmitter / receiver is configured to include a modulator that modulates data using the modulation scheme specified by the channel quality estimator 7 and a transmitter that transmits a signal modulated by the modulator. Has been.
JP 2003-101419 A Japanese Patent Application Laid-Open No. 09-200222 Hashimoto, Kamei et al., "Long-Period Interleaved Transmission System", IEICE Technical Report, SAT 2001-93, pp. 69-76, Jan. 2002.

  However, in such a conventional long-period interleave transmission technique, the modulation scheme is fixed within each interleave period, so that rainfall interception (see FIG. 14) is prevented as much as possible over a plurality of interleave periods, and the data There is a problem that it is necessary to perform interleaving with a long period of, for example, 24 hours or the like in order to make it possible to compensate for errors well.

The present invention has been made in order to solve this problem without reducing the service time ratio and provides an interleaved transmission apparatus and interleaving receiving equipment which can shorten the interleave period.

In view of the above points, the invention according to claim 1 is an interleaving that performs long-period interleaving on input data, modulates the interleaved data, and transmits the data to an external interleave receiving device. In the transmission device, data of communication quality between the interleave transmission device and the interleave reception device transmitted from the interleave reception device is received, and the interleaved data is performed according to the received communication quality information A modulation scheme update processing unit configured to set a modulation scheme that maximizes frequency efficiency among a plurality of modulation schemes as a modulation scheme performed by the interleave transmission apparatus according to the received communication quality information And the interleaving is performed at a reading speed set by the modulation method update processing unit. Means to read out the data, the modulation scheme by the modulation scheme set by the update processing unit, and means for modulating the data read, the data in which the interleaving is performed modulation scheme updating unit And a means for transmitting to the interleave receiving apparatus by combining the modulation schemes set by .

  With this configuration, since the modulation scheme can be updated within each interleave period according to the communication quality of the received data transmission, an interleave transmission apparatus capable of shortening the interleave period without reducing the service time rate is provided. Can be realized.

  Further, the invention according to claim 2 is the invention according to claim 1, wherein the modulation scheme update processing unit receives information on a bit error rate of data received by the interleave receiving device, and sets the bit error rate to C / N. It is determined by the real-time C / N conversion unit that calculates the converted C / N, the required C / N determination unit that determines the required C / N according to the converted C / N, and the required C / N determination unit. An interleaved reading speed setting unit that generates a reading speed setting signal for setting an interleaving reading speed according to the required C / N, and a modulation method according to the required C / N determined by the required C / N determining unit. A modulation scheme setting unit for generating a modulation scheme setting signal to be set, and the interleave transmission device reads the data subjected to the interleaving at a reading speed according to the reading speed setting signal. Out, it has a configuration of performing modulation with the modulation scheme corresponding to the modulation method setting signal.

  With this configuration, in addition to the effect of the first aspect, received bit error rate information is converted into C / N information to control interleave transmission, so that it is possible to easily determine the modulation scheme setting. A simple interleave transmission device can be realized.

According to a third aspect of the present invention, the demodulated information and predetermined data are received, the data is demodulated by the demodulation method specified based on the demodulated information, and the demodulated data is received. An interleave receiving apparatus that performs de-interleaving generates information on communication quality between the interleave transmitting apparatus and the interleave receiving apparatus according to claim 1 based on the demodulated data, and the interleave transmitting apparatus A bit error rate measurement unit that transmits data to a long-period deinterleave unit that writes data for performing the deinterleave at the write speed specified based on the demodulation method information ing.

  With this configuration, information on the communication quality of data transmission is transmitted to the interleave transmission device, and deinterleave writing is performed according to the demodulation method, so that the modulation method at the interleave transmission device can be determined according to the communication quality. It is possible to realize an interleave receiving apparatus that can perform deinterleaving according to the modulation method and can shorten the interleaving cycle without reducing the service time rate.

  Also, in the invention according to claim 4 according to claim 3, the bit error rate measuring unit calculates a bit error rate of received data, and uses the bit error rate information as the communication quality information as the interleave transmission. It has the structure which transmits to an apparatus.

  With this configuration, in addition to the effect of claim 1, since the communication quality information is transmitted as the bit error rate information, an interleave receiving apparatus capable of providing accurate and detailed communication quality information can be realized. .

  In the present invention, the modulation scheme in interleave transmission is determined according to the communication quality, and interleaving or deinterleaving is performed according to the determined modulation scheme, so that the interleaving cycle can be shortened without reducing the service time rate. It is possible to realize an interleave transmission device, an interleave reception device, and an interleave transmission program that can be used.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing a block configuration of an interleave transmission apparatus according to the first embodiment of the present invention. In the first embodiment, an apparatus that performs one-to-one communication will be described. In FIG. 1, an interleave transmission apparatus 100 includes a long period interleaving unit 110, an outer code encoding unit 121, a short period interleaving unit 122 (shown as “short cycle IL unit 122” in FIG. 1), and an inner code encoding unit 123. , Modulation section 124, transmission section 125, and modulation scheme update processing section 130, interleave transmission apparatus 101, reception section 141, demodulation section 142, inner code decoding section 143, short period deinterleaving section 144 (see FIG. 1). "Shown as" short cycle DIL unit 144 "), outer code decoding unit 145, bit error rate measurement unit 146 (shown as" BER (Bit Error Rate) measurement unit 146 "in FIG. 1), deinterleave writing speed setting Unit 147 (shown as “DIL writing speed setting unit 147” in FIG. 1), and long-period deinterleaving unit 15 Configuration consists of interleaving the receiving apparatus 102., including.

  FIG. 2 is a functional block diagram showing the configuration of the interleave transmission apparatus disclosed in Patent Document 1 described above in association with the present invention. Interleave transmission apparatus 100 according to the first embodiment of the present invention adds modulation scheme update processing section 130 to interleave transmission apparatus 201 of the conventional interleave transmission apparatus, and provides DIL write speed setting section 147 to interleave reception apparatus 202. And a BER measurement unit 146.

  As conceptually shown in FIG. 3, the present invention switches the modulation method as described later while maintaining the amount of information to be transmitted, and changes the interleaving period (hereinafter simply referred to as “interleaving period”) to the conventional interleaving. It is intended to shorten the period. In FIG. 3, an example of a conventional interleaving cycle is indicated by a symbol (A), and (B) indicates an interleaving cycle of the present invention. In the past (A), the modulation method was fixed regardless of the weather. On the other hand, in the present invention of (B), the modulation method is switched according to the weather. Specifically, when the C / N (Carrier to Noise Ratio) of the transmission line is high as in clear weather, a modulation scheme with high frequency utilization efficiency is used, and when the C / N of the transmission line is low as in rainy weather. Switching to a method with low frequency utilization efficiency. Here, the frequency utilization efficiency is an index indicating a measure of the amount of information that can be transmitted using a target frequency.

  FIG. 4 is an explanatory diagram conceptually showing the format of an interleave frame. Here, the interleaved frame refers to a frame generated by two-dimensionally arranging the total data that can be accumulated within the interleaving time, including the parity, as conceptually shown in FIG. In FIG. 4, “data” indicates data to be transmitted, and “parity” indicates data (parity) used for error correction.

  Hereinafter, the configuration of the interleave transmission apparatus according to the first embodiment of the present invention will be described in detail. First, long-period interleaving section 110 of interleave transmission apparatus 101 further includes interleave writing section 111 (shown as “IL writing section 111” in FIG. 1), outer / outer code encoding section 112, and interleave data reading section. 113 (shown as “IL data reading unit 113” in FIG. 1). The modulation scheme update processing unit 130 includes a real-time C / N conversion unit 131, a required C / N determination unit 132, and an interleave reading speed. Setting section 133 (shown as “IL reading speed setting section 133” in FIG. 1) and modulation scheme setting section 134 are configured. Further, long-period deinterleaving section 150 of interleave receiving apparatus 102 further includes deinterleaving writing section 151 (shown as “DIL writing section 151” in FIG. 1), outer / outer code decoding section 152, and deinterleave data. A reading unit 153 (shown as “DIL data reading unit 153” in FIG. 1) is included.

  First, the interleave transmission apparatus 101 shown in FIG. 1 will be described.

  Input data such as video data and audio data is input to the IL writing unit 111 of the interleave transmission apparatus 101, and the IL writing unit 111 interleaves the input data and records it on a recording medium (not shown). ing. The direction of writing is shown with reference numeral (1) in FIG. The recording medium may be a hard disk, for example.

  The outer / outer code encoding unit 112 generates error correction code parity (outer / outer code parity) in the data written by the IL writing unit 111 in the vertical direction (the direction indicated by the code (2) in FIG. 4). As shown conceptually in FIG. 4, they are added in the vertical direction.

  The IL data reading unit 113 reads the data to which the outer / outer code parity is added by the outer / outer code encoding unit 112 from the recording medium. As shown in FIG. 4, the direction in which data is written by the IL writing unit 111 and the direction in which data is read by the IL data reading unit 113 are the same. Here, the IL data reading unit 113 receives a later-described reading speed setting signal output from the modulation method update processing unit 130, and the IL data reading unit 113 reads data at a reading speed corresponding to the reading speed setting signal. .

  The outer code encoding unit 121 cuts out data from the data output from the IL data reading unit 113 at regular intervals, adds an outer code parity, and returns the data. FIG. 5 is a diagram conceptually showing the data after the outer code parity is added to the data output from IL data reading section 113. As shown in FIG. 5, the outer code parity is also added to the data string composed of the outer code parity. Here, the signal to which the outer code parity is added by the long-period interleaving unit 110 and the outer code parity is added by the outer code coding unit 121 forms a product code. The product code is a code obtained by combining a plurality of codes, and is known for its high error correction capability. An error correction code used in the Reed-Solomon code may be used as the outer code parity.

  The short cycle IL unit 122 receives data to which the outer code parity and the outer code parity are added, and the short cycle IL unit 122 performs short cycle interleaving. Here, short cycle interleaving refers to interleaving of a cycle shorter than the cycle of interleaving performed by long cycle interleaving section 110. The short cycle IL unit 122 performs interleaving with a depth of about 10, for example. Here, the depth of interleaving is defined as the number of sets of data and parity in the horizontal direction shown in FIG.

  The inner code encoding unit 123 receives data after short-cycle interleaving is performed, cuts out data from the data at regular intervals, adds an outer code parity, and returns the data. An error correction code used in the convolutional code may be used as the inner code parity.

  Data to which the inner code parity is added by the inner code coding unit 123 is input to the modulation unit 124, and the modulation unit 124 performs digital modulation such as QPSK (Quadrature Phase shift keying) or 16QAM (Quadrature Amplitude Modulation). To do. Here, a modulation scheme setting signal, which will be described later, output from the modulation scheme update processing section 130 is input to the modulation section 124, and the modulation section 124 modulates with a modulation scheme according to the modulation scheme setting signal.

  A signal obtained by performing modulation by the modulation unit 124 is input to the transmission unit 125, and the transmission unit 125 transmits a modulated signal (modulated wave). The technique for transmitting the modulated signal is well known and will not be described.

  Next, the modulation scheme update processing unit 130 of the interleave transmission apparatus 101 will be described.

  In the modulation scheme update processing unit 130, data (hereinafter referred to as “BER data”) of a bit error rate (hereinafter referred to as “BER”) of a signal received by the interleave receiving apparatus 102 is stored in a BER measurement unit 146 described later. Is input via a predetermined transmission line. Here, the predetermined transmission path may be, for example, a telephone line.

The real-time C / N conversion unit 131 receives the BER data from the BER measurement unit 146, and the real-time C / N conversion unit 131 calculates the converted C / N by converting the input BER into C / N. It has become. Here, the conversion from the BER to the converted C / N may be performed based on, for example, a C / N vs. BER characteristic obtained by measurement or the like in advance as shown in FIG. In FIG. 6, required C / N refers to C / N necessary for securing a predetermined quality (BER) in data transmission. Here, the required C / N line is a line indicating a BER value corresponding to the required C / N, and FIG. 6 shows an example in which the BER corresponding to the required C / N is 10 ⁻⁴ . Further, FIG. 6 shows that the required C / N increases as the modulation scheme with higher frequency utilization efficiency.

  The required C / N determination unit 132 receives the converted C / N data obtained by conversion by the real-time C / N conversion unit 131, and the required C / N determination unit 132 receives the converted C / N data. And the required C / N are compared to determine a required C / N equal to or lower than the converted C / N and closest to the converted C / N, and information including the determination result (hereinafter simply referred to as “determined required C / N”). N information ”) is output to the IL reading speed setting unit 133 and the modulation method setting unit 134.

  Determination required C / N information from the required C / N determination unit 132 is input to the IL read speed setting unit 133, and the IL read speed setting unit 133 is based on the determination required C / N information. The read speed of the data read performed by is determined, and a read speed setting signal containing the read speed is generated and output to the IL data reading unit 113. The reading speed may be determined based on a correspondence table of required C / N and reading speed generated in advance.

  The required modulation C / N information from the required C / N determination unit 132 is input to the modulation scheme setting unit 134, and the modulation scheme setting unit 134 performs the modulation performed by the modulation unit 124 based on the determination required C / N information. A modulation scheme is specified, a modulation scheme setting signal containing the identified modulation scheme is generated, and output to the modulation section 124. The modulation scheme may be specified based on a correspondence table between required C / Ns and modulation schemes generated in advance.

  Next, the interleave receiving apparatus 102 will be described.

  The reception unit 141 is configured to receive a signal (modulated wave) from the transmission unit 125 of the interleave transmission device 101. Since the signal receiving technique is known, the description thereof is omitted.

  The demodulator 142 of the interleave receiving apparatus 102 demodulates the signal (modulated wave) received by the receiver 141. Here, the demodulation method performed by the demodulation unit 142 may be specified by using, for example, a conventional TMCC (Transmission and Multiplication Configuration and Control) signal. The transmission of modulation (or demodulation) information using a TMCC signal is well known and will not be described.

  The inner code decoding unit 143 receives a signal obtained as a result of demodulation by the demodulating unit 142 (hereinafter simply referred to as “demodulated signal”), and the inner code decoding unit 143 uses the inner code for the inner code included in the demodulated signal. Error correction (hereinafter referred to as “inner code decoding”) is performed using parity to generate an inner code decoded signal. Error correction using the parity for the inner code is known and will not be described.

  The short cycle DIL unit 144 receives the inner code decoded signal generated by the inner code decoding unit 143, and the short cycle DIL unit 144 performs short cycle deinterleaving on the inner code decoded signal. Yes. Here, “short cycle deinterleaving” refers to returning the data rearranged by the short cycle interleaving performed by the short cycle IL unit 122 to the original state.

  By performing the short cycle deinterleaving in this way, the data (data conceptually shown in FIG. 5) obtained by the interleave transmission apparatus 101 performing the long cycle interleaving is restored (see FIG. 7). In general, the restored data includes a defect as shown by a black square in FIG. FIG. 7 shows an example in which data loss occurs in isolation and an example of “burst” that occurs continuously. FIG. 7 conceptually shows that a burst is caused by rainfall and the burst is not longer than the interleave period.

  The outer code decoding unit 145 receives a short-cycle deinterleaved signal (hereinafter simply referred to as “short-cycle deinterleave signal”), and uses the outer-code parity included in the short-cycle deinterleave signal to generate an error. Correction (hereinafter referred to as “outer code decoding”) is performed. Error correction using the outer code parity is well known and will not be described. The outer code decoding unit 145 restores data as conceptually shown in FIG. The restored data generally includes missing data, but is not shown in FIG.

  The BER measuring unit 146 receives the demodulated signal and the inner code decoded signal, and the BER measuring unit 146 compares the demodulated signal and the inner code decoded signal to calculate the BER. The BER data calculated by the BER measurement unit 146 is transmitted to the real-time C / N conversion unit 131 of the modulation method update processing unit 130 described above. The modulation scheme update processing unit 130 updates the modulation scheme based on the BER data transmitted from the BER measurement unit 146. The BER data is transmitted to the interleave transmission device 101 via, for example, the Internet line.

  The DIL writing speed setting unit 147 receives information on the modulation (or demodulation) method, and the DIL writing speed setting unit 147 writes the deinterleave based on the input information on the modulation (or demodulation) method. The speed is determined, a signal having the deinterleave writing speed as a content is generated as a writing speed setting signal, and is output to the long period deinterleaving unit 150 (DIL writing unit 151). The above-described writing speed may be determined based on a correspondence table of modulation (or demodulation) methods and writing speeds generated in advance.

  A signal obtained by performing outer code decoding is input to the DIL writing unit 151 of the long-period deinterleaving unit 150, and the DIL writing unit 151 writes data for long-period deinterleaving. It has become. Here, the writing speed is determined according to the writing speed setting signal output from the DIL writing speed setting unit 147. Thus, by determining the writing speed according to the writing speed setting signal from the DIL writing speed setting unit 147, the influence of the change of the modulation (or demodulation) system can be absorbed. Data is written on a recording medium (not shown) such as a hard disk.

  The outer / outer code decoding unit 152 performs error correction (hereinafter referred to as “outer / outer code decoding”) on the data written on the recording medium by the DIL writing unit 151 using the outer / outer code parity included in the data. )). Error correction using the outer / outer code parity is well known, and its description is omitted. Data subjected to all error correction processing is generated by outer / outer code decoding.

  The DIL data reading unit 153 reads data after outer / outer code decoding from a recording medium and outputs the data as received data to an external device. Note that the data is read in the same direction as the direction of writing performed by the IL writing unit 111 of the interleave transmission apparatus 101 to restore the source data (input data of the interleave transmission apparatus 101).

  The operation of modulation scheme update processing section 130 of interleave transmission apparatus 101 according to the first embodiment of the present invention will be described below. FIG. 8 is a flowchart showing a process flow in the modulation scheme update processing unit 130 of the interleave transmission apparatus 101 according to the first embodiment of the present invention.

  First, the BER data from the BER measurement unit 146 is received by the real-time C / N conversion unit 131 (S801), and the conversion C / N obtained by converting the BER into C / N is calculated (S802). Next, the required C / N determination unit 132 compares the converted C / N with the required C / N of each modulation method, and determines the required C / N equal to or lower than the converted C / N and closest to the converted C / N. (S803-1 to S803-N). Here, the comparison is performed in order from the modulation scheme having the highest information transmission rate (the amount of information that can be transmitted within a unit time) as shown in FIG. In FIG. 8, the required C / N of 16QAM (3/4) in step S803-1, the required C / N of TC8PSK (2/3) in step S803-2,..., QPSK (2 in step S803-N / 3) in order of required C / N. Note that TC8PSK indicates Trellis Coded 8 Phase Shift Keying, and the fraction in parentheses of the modulation scheme indicates a coding rate. In FIG. 8, QPSK (1/2) is shown as the case of the modulation scheme with the lowest information transmission rate. By doing in this way, the required C / N is compared in descending order.

  If it is determined in steps S803-1 to S803-N that the required C / N less than or equal to the converted C / N is closest to the converted C / N, the IL read speed setting unit 133 corresponds to the determined required C / N. The reading speed to be determined is determined, and a reading speed setting signal containing the reading speed is generated (S804-1 to S804-N). In the case shown in FIG. 8, for example, when it is determined in step S803-1 that the converted C / N is equal to or greater than the required C / N of 16QAM (3/4), in step S804-1 for 16QAM (3/4) Set the reading speed.

  When the reading speed setting signal is generated in steps S804-1 to S804-N, the modulation method setting unit 134 specifies the modulation method corresponding to the determined required C / N, and the specified modulation method is the content. A modulation system setting signal is generated (S8055-1 to S805-N). In the case shown in FIG. 8, for example, when the reading speed for 16QAM (3/4) is set in step S804-1, 16QAM (3/4) is set as the modulation method in step S805-1.

  If it is determined in step S803-N that the converted C / N is smaller than the required C / N of QPSK (2/3), a speed for QPSK (1/2) is set as the reading speed, and modulation is performed. QPSK (1/2) is set as the method. This is because, in this embodiment, QPSK (1/2) is the modulation scheme with the slowest information transmission rate.

  When the modulation scheme is set in steps S805-1 to S805- (N + 1), the real-time C / N conversion unit 131 determines whether or not the processing in each of the above steps has been completed for all received data. If it is determined that the process has not been completed, the process returns to step S801, and the above process is repeated. If it is determined that the process has been completed, the process ends (S806).

  When data is transmitted using a modulation method other than QPSK (1/2), the amount of information that can be sent per unit time is larger than that of QPSK (1/2), so that transmission can be performed in a shorter time than the set interleave time. become. On the other hand, when the required C / N of QPSK (2/3) cannot be secured due to heavy rain within the set interleaving time, QPSK (1/2) is transmitted as a modulation method.

  In the conventional transmission method, the modulation method is fixed to QPSK (1/2) and interleaved transmission is performed. However, in the method of switching the modulation method of the present invention (hereinafter simply referred to as “modulation method switching method”). Conversion from the modulation scheme with the highest frequency utilization efficiency (16QAM (3/4) in the example shown in FIG. 8) to the modulation scheme with the lowest frequency utilization efficiency (QPSK (1/2) in the example shown in FIG. 8) employed in the modulation unit It is possible to adaptively switch according to C / N.

  The following describes how the amount of data read and written on the interleave frame changes when the modulation method is switched when interleaving is performed using this modulation method switching method, with reference to FIG. I will explain. At that time, the conventional transmission method (modulation method is QPSK (1/2), interleaving over 8 hours) is assumed to be a reference.

  First, the interleave data is written in the interleave transmitting apparatus 101 (IL writing unit 111) as in the past, as shown in FIG. 9A, taking 8 hours. As shown in FIG. 9B, reading of the interleaved data written by the interleave transmitting apparatus 101 is performed, for example, over 2 hours at a 16 QAM reading speed and over 2 hours at a QPSK reading speed. Conventionally, the reading speed has been fixed as the modulation method is fixed. However, in the modulation system switching system of the present invention, since the modulation system is adaptively switched, for example, when the modulation system is switched to 16QAM (3/4), it is three times that of QPSK (1/2). Data can be transmitted at high speed. In the example shown in FIG. 3, QPSK (1/2) transmission is performed by combining 2-hour transmission with a modulation scheme of 16QAM (3/4) and 2-hour transmission with a modulation scheme of QPSK (1/2). The system can transmit 8 hours of interleaved data.

  Next, the writing of data for deinterleaving in the interleave receiving apparatus 102 (DIL writing unit 151) is performed as shown in FIG. 9C. In the example of FIG. 9C, the writing is performed for 2 hours at the writing speed for 16QAM and over 2 hours for the writing speed for QPSK. Since data is transmitted using an adaptive modulation scheme, the interleave receiving apparatus 102 writes interleaved data at a speed compatible with the modulation scheme. Conventionally, the interleaving write time takes 8 hours for QPSK (1/2), but 16QAM (3/4) and QPSK (1/2) modulation as in the modulation method switching system of the present invention. When transmission is performed using a combination of methods, writing is completed in 4 hours. After the error correction is performed, only the data is read out, and the data can be viewed at any time. As shown in FIG. 9D, the deinterleaved data is read out for 8 hours at the reading speed for the initially set QPSK (1/2).

  As described above, in the interleave transmission device according to the first embodiment of the present invention, the modulation scheme performed by the modulation unit of the interleave transmission device is changed to information on communication quality of data transmission (here, converted C / C N) to switch to a modulation method with a high information transmission rate, and to perform interleaved transmission by reading interleaved data at a reading rate according to the switched modulation method, so that the interleaving period can be set without reducing the service time rate. It can be shortened.

  Further, since the received bit error rate information is converted into C / N information to control interleave transmission, it is possible to easily determine the modulation scheme setting.

  Also, in the interleave receiving apparatus according to the first embodiment of the present invention, information on communication quality of data transmission (here, data error rate) is transmitted to the interleave transmitting apparatus, and deinterleave writing is performed according to the demodulation method. Therefore, the modulation scheme in the interleave transmission device can be determined according to the communication quality, and deinterleaving can be written according to the modulation scheme, and the interleaving cycle can be shortened without reducing the service time rate. A possible interleave receiving device can be realized.

  Further, since communication quality information is transmitted as bit error rate information, accurate and detailed communication quality information can be provided.

  In the first embodiment of the present invention, the interleave transmission operation in which the processes in the above steps S801 to S806 are performed using the interleave transmission apparatus has been described. However, the processes in these steps S801 to S806 are performed. The same effect can be obtained by using a predetermined computer in which an interleave transmission program for execution is installed.

(Second Embodiment)
FIG. 10 is a diagram showing a block configuration of an interleave transmission apparatus 100 according to the second embodiment of the present invention. FIG. 10 conceptually shows a configuration in the case where there are a plurality of interleave receiving apparatuses for one interleave transmitting apparatus 1001. In FIG. 10, the configuration of each of the interleave receiving apparatuses 102-1 to 102-N of the interleave transmission apparatus according to the second embodiment of the present invention is the same as that according to the first embodiment of the present invention. The description is omitted.

  In FIG. 10, conversion units 131-1 to 131-N are the same as real-time C / N conversion unit 131 described in the first embodiment of the present invention. BER data 1 to BER data N transmitted from -N are input, and converted C / N1 to converted C / NN obtained by converting the input BER into C / N are calculated.

  Each of the interleave receiving apparatuses 102-1 to 102-N transmits BER data 1 to BER data N to the interleave transmitting apparatus 1001 at predetermined time intervals via a predetermined network such as an Internet line (not shown). . Here, a node station may be provided on the network, and the node station may receive the BER data 1 to BER data N in a concentrated manner and transmit the BER data 1 to BER data N to the interleave transmission apparatus 1001. By doing in this way, the conversion part can be reduced to one.

  Further, the node station and the interleave transmission device 1001 may be connected by a dedicated line so that high-speed data transmission can be performed. By doing in this way, even when the number N of interleave receiving apparatuses 102-1 to 102-N is large, reception of data of BER data 1 to BER data N from each of the interleave receiving apparatuses 102-1 to 102-N is performed. It becomes possible to make it appropriate.

  Further, not all interleave receiving apparatuses transmit BER data, but only a predetermined interleave receiving apparatus may transmit BER data. BER data does not need to be transmitted from all interleave receiving apparatuses. If an interleave receiving apparatus having a high bit error rate is known in advance, it is only necessary to transmit BER data from a predetermined number of interleave receiving units including this. Because it is good.

  Information on converted C / N1 to converted C / NN output from each conversion unit 131-1 to 131-N is input to minimum C / N determination unit 1032 and input to minimum C / N determination unit 1032 is input. The lowest value of the converted C / N1 to the converted C / NN is selected based on the converted C / N1 to the converted C / NN information, and is output to the required C / N determination unit 132. The required C / N determination unit 132 sets the lowest value of the converted C / N1 to the converted C / NN as the converted C / N of the first embodiment of the present invention, and is set as the converted C / N. The required C / N is compared to generate the above-described required determination C / N information and output it to the IL read speed setting unit 133 and the modulation method setting unit 134.

  By configuring the minimum C / N determination unit 1032 in this way, it is possible to ensure predetermined data transmission quality for each of the interleave receiving apparatuses 102-1 to 102-N.

  Hereinafter, the operation of the modulation scheme update processing unit 1030 of the interleave transmission apparatus 1001 according to the second embodiment of the present invention will be described. FIG. 11 is a flowchart showing a process flow in the modulation scheme update processing unit 1030 of the interleave transmission apparatus 1001 according to the second embodiment of the present invention. Of the processing steps in the modulation scheme update processing unit 1030 of the interleave transmission apparatus 1001 according to the second embodiment of the present invention, the modulation scheme update of the interleave transmission apparatus 101 according to the first embodiment of the present invention. Steps for performing the same processing as the processing in the processing unit 130 are denoted by the same reference numerals and description thereof is omitted.

  First, BER data 1 to BER data N transmitted from each of the interleave receiving apparatuses 102-1 to 102-N are received via the conversion units 131-1 to 131-N, respectively (S1101). When there is one conversion unit, for example, a series of BER data 1 to BER data N transmitted from the node station may be received.

  Next, the conversion units 131-1 to 131-N convert the BER data 1 to BER data N received in step S1101 into C / N data to generate converted C / N1 to converted C / NN data. (S1102-1). The process of converting the BER into C / N and calculating the converted C / N1 to the converted C / NN is the same as the process performed in step S802 in the first embodiment of the present invention, and the description thereof is omitted.

  Next, the lowest value among the converted C / N1 to the converted C / NN generated in step S1102-1 is selected (S1102-2). In step S803-1, the lowest converted C / N is defined as the converted C / N generated in step S802 described in the first embodiment of the present invention. Are compared.

  As described above, the interleave transmission apparatus according to the second embodiment of the present invention, when there are a plurality of interleave reception apparatuses, interleave reception with the worst reception quality among the reception qualities of each interleave reception apparatus. Since the reception quality of the apparatus can be received well, even when there are a plurality of interleave receiving apparatuses, as in the interleave transmission apparatus according to the first embodiment of the present invention, the service time rate is not reduced. The interleaving cycle can be shortened.

  In the second embodiment of the present invention, the interleave transmission operation for performing the processes in the above steps S1101, S1102-1, S1102-2, S803-1 to S806 using the interleave transmission apparatus has been described. However, the same effect can be obtained even when the program is executed using a predetermined computer in which an interleave transmission program for executing the processing in steps S1101, S1102-1, S1102-2, and S803-1 to S806 is installed. be able to.

Interleaving transmission apparatus and interleaving receiving equipment according to the present invention, without reducing the service time rate, can be applied to useful interleaving transmitting apparatus and interleave receiving instrumentation 置等 applications to shorten the interleave period.

It is a figure which shows the block configuration of the interleave transmission apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the block configuration of the conventional interleave transmission apparatus. It is explanatory drawing of the interleave transmission of this invention. It is explanatory drawing which shows notionally the format of an interleave frame. It is a figure which shows notionally the data after adding the parity for outer codes. It is explanatory drawing which shows an example of a C / N vs. BER characteristic. It is a figure which shows notionally an example of the received data. It is a flowchart which shows the flow of a process in the modulation system designation | designated part of the interleave transmission apparatus which concerns on the 1st Embodiment of this invention. It is explanatory drawing of the modulation system switching system of this invention. It is a figure which shows the block configuration of the interleave transmission apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the flow of a process in the modulation system designation | designated part of the interleave transmission apparatus which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating the principle of the conventional long period interleave transmission technique. It is a figure which shows the one part block structure of the conventional adaptive modulation system transmission / reception apparatus for TDD. It is a figure which shows notionally an example of the reception data when rain interruption occurs over an interleave period.

Explanation of symbols

2 Modulation unit 6 Error correction unit 7 Channel quality estimation unit 100, 200, 1000 Interleave transmission device 101, 201, 1001 Interleave transmission device 102, 102-1 to 102-N, 202 Interleave reception device 110 Long-period interleaving unit 111 Interleave document Insertion unit 112 Outer outer code encoding unit 113 Interleave data reading unit 121 Outer code encoding unit 122 Short cycle interleaving unit 123 Inner code encoding unit 124 Modulating unit 125 Transmitting unit 130, 1030 Modulation method update processing unit 131, 131-1 131-N Real-time C / N conversion unit 132 Required C / N determination unit 133 Interleave reading speed setting unit 134 Modulation method setting unit 141 Receiving unit 142 Demodulating unit 143 Inner code decoding unit 144 Short period deinterleaving unit 145 Outer code Signal decoding unit 146 Bit error rate measurement unit 147 Deinterleave writing speed setting unit 150 Long period deinterleaving unit 151 Deinterleaving writing unit 152 Outer / outer code decoding unit 153 Deinterleaved data reading unit 1032 Minimum C / N selection unit

Claims (4)

In an interleave transmission device that performs long-period interleaving on input data, modulates the interleaved data, and transmits the data to an external interleave reception device.
The communication quality information between the interleave transmission device and the interleave reception device transmitted from the interleave reception device is received, and the read speed of the data subjected to the interleaving is determined according to the received communication quality information. A modulation scheme update processing unit that sets and sets a modulation scheme that maximizes frequency efficiency among a plurality of modulation schemes according to the received communication quality information as a modulation scheme performed by the interleave transmission device;
Means to read out the data to which the interleaving is performed in reading speed set by the modulation scheme update processing unit, the modulation scheme set by the modulation scheme update processing unit, the modulation of the data read An interleave transmission apparatus comprising: means for performing transmission; and means for transmitting the interleaved data to the interleave reception apparatus by combining the modulation scheme set by the modulation scheme update processing unit . The modulation method update processing unit receives information on a bit error rate of data received by the interleave receiving device, and calculates a converted C / N obtained by converting the bit error rate into a C / N. A required C / N determination unit that determines a required C / N according to the converted C / N, and an interleave reading speed according to the required C / N determined by the required C / N determination unit. An interleaved reading speed setting unit for generating a reading speed setting signal; and a modulation method setting unit for generating a modulation method setting signal for setting a modulation method according to the required C / N determined by the required C / N determination unit. The interleave transmission device reads the interleaved data at a reading speed corresponding to the reading speed setting signal, and uses a modulation scheme corresponding to the modulation scheme setting signal. Interleaving transmission device according to claim 1, characterized in that the tone. In an interleave receiving device that receives demodulation method information and predetermined data, demodulates the data in a demodulation method specified based on the demodulation method information, and deinterleaves the demodulated data,
A bit error rate measurement unit that generates communication quality information between the interleave transmission device according to claim 1 and the interleave reception device based on the demodulated data and transmits the information to the interleave transmission device;
An interleave receiving apparatus comprising: a long-period deinterleaving unit that writes data for performing the deinterleaving at a writing speed specified based on information of the demodulation method.   The bit error rate measurement unit calculates a bit error rate of received data, and transmits the bit error rate information as the communication quality information to the interleave transmission device. Interleave receiver.

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