JP2017200126A - Ofdm signal transmitting device and ofdm signal receiving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve effects of frequency interleaving and to improve reception characteristics in partial reception of ISDB-T.SOLUTION: A carrier modulation part 11 of an OFDM signal transmitting device 1-1 modulates data A for partial reception to generate a data carrier a, and a carrier modulation part 12 modulates data B for fixed reception to generate a data carrier b. A separation part 13 separates the data carrier b into a data carrier b1 and a data carrier b2. An interleaving part 14 performs frequency interleaving on the data carrier a, b2 corresponding to a segment region α for partial reception and a region β2 for fixed reception within a partial reception bandwidth γ. An interleaving part 15 performs frequency interleaving on the data carrier b1 corresponding to a region β1 for fixed reception not within the partial reception bandwidth γ.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an OFDM signal transmitting apparatus that performs frequency interleaving and an OFDM signal receiving apparatus that performs frequency deinterleaving.

  Conventionally, ISDB-T (Integrated Services Digital Broadcasting-Terrestrial) is used as a current terrestrial digital broadcasting system in Japan (see, for example, Non-Patent Document 1). In ISDB-T, a frequency band of a plurality of subcarriers that are orthogonal frequency division multiplexed (OFDM) assigned to one broadcast wave (channel) is divided into 13 segments.

  Of the 13 segments, 12 segments are used for fixed reception high-definition broadcasting and multiple standard-definition broadcasting, and the remaining one segment is used for mobile reception broadcasting. Broadcast data is transmitted simultaneously in the frequency bands of these 13 segments.

  On the other hand, a new next-generation terrestrial digital broadcasting that replaces the existing terrestrial digital broadcasting is being studied. In next-generation terrestrial digital broadcasting, it is required to provide services such as 3D high-definition broadcasting or super-high-definition broadcasting having 16 times the resolution of high-definition broadcasting instead of conventional high-definition broadcasting for fixed reception at home and the like ing. In services such as super high-definition broadcasting, the amount of information is larger than in conventional high-definition broadcasting.

  Similarly, there is a need to provide high-definition services for mobile reception. Similar to the current ISDB-T, it is necessary to provide these two services for fixed reception and mobile reception simultaneously using one channel.

ARIB STD-B31, "Transmission method for digital terrestrial television broadcasting"

  FIG. 8 is a diagram showing a segment structure of ISDB-T. The horizontal axis indicates the frequency. As described above, in ISDB-T, one channel is composed of 13 segments. Of the 13 segments, 12 segments are used for broadcasting for fixed reception, and the remaining one segment is used for broadcasting for mobile reception (for partial reception). That is, ISDB-T partial reception is configured with one segment (bandwidth 3000/7 = 428.57... KHz).

  Within one channel, one segment area for partial reception at the center is set as a partial reception segment area α, and 12 segment areas for fixed reception arranged on both sides of the partial reception segment area α are fixed reception. Segment area β.

  The data set in the fixed reception segment area β shown in FIG. 8 is subjected to frequency interleaving within the 12 segments in the OFDM signal transmitting apparatus. On the other hand, the data set in the partial reception segment area α is subjected to frequency interleaving and frequency carrier randomization within the one segment. That is, the data set in the partial reception segment area α is not subjected to frequency interleaving using a wide band like the fixed reception segment area β of another layer.

  For this reason, in the OFDM signal receiving apparatus that receives the OFDM signal in the partial reception segment area α, there is a problem that the effect of frequency interleaving is low and reception characteristics are deteriorated.

  Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to improve the frequency interleaving effect in the partial reception of ISDB-T and to improve the reception characteristics of the OFDM signal transmission. The present invention provides an apparatus and an OFDM signal receiving apparatus.

  In order to solve the above-mentioned problem, an OFDM signal transmission apparatus according to claim 1 is configured such that an OFDM signal including partial reception data and fixed reception data is divided into a segment structure including a partial reception segment area and a fixed reception segment area. In the OFDM signal transmitting apparatus for transmitting in the band of 1, the partial reception data carrier is generated by modulating the partial reception data, and the fixed reception data carrier is generated by modulating the fixed reception data The fixed reception data carrier generated by the carrier modulation unit is set to the fixed by using a carrier modulation unit and an area composed of the partial reception segment area and a part of the fixed reception segment area as a partial reception bandwidth. A first fixed area corresponding to an area other than a part of the fixed reception segment area among the reception segment areas. A separation unit that separates the reception data carrier into a second fixed reception data carrier corresponding to a part of the fixed reception segment area; and the partial reception data carrier generated by the carrier modulation unit and the separation An interleaving unit that performs frequency interleaving on the second fixed reception data carrier separated by the separation unit and performs frequency interleaving on the first fixed reception data carrier separated by the separation unit; The partial reception data carrier and the second fixed reception data carrier subjected to the frequency interleaving by the interleaving unit are set in the partial reception bandwidth region, and the interleaving unit sets the frequency. The first fixed reception data that has been interleaved. A framing unit that configures an OFDM frame so that a carrier is set in a region other than a part of the fixed reception segment region in the fixed reception segment region, and the OFDM frame configured by the framing unit IFFT unit for IFFT and converting the frequency domain signal to the time domain signal, and the time domain signal converted by the IFFT unit from the partial reception segment area and the fixed reception segment area And a transmitter for transmitting the OFDM signal via a transmission antenna in a segment structure band.

  An OFDM signal transmission apparatus according to claim 2 is the OFDM signal transmission apparatus according to claim 1, wherein a part of the fixed reception segment area included in the partial reception bandwidth is divided into predetermined segment positions. Or a region with a predetermined carrier position in the segment as a delimiter.

  The OFDM signal transmission apparatus according to claim 3 is the OFDM signal transmission apparatus according to claim 1 or 2, wherein the frequency interleaving by the interleaving unit is a frequency interleaving in units of segments or a frequency interleaving in units of carriers. It is characterized by.

  An OFDM signal transmission apparatus according to claim 4 is the OFDM signal transmission apparatus according to any one of claims 1 to 3, further comprising TMCC including information on the partial reception bandwidth and information on the frequency interleaving. A TMCC generation unit that generates a signal is provided, and the framing unit constitutes an OFDM frame including the TMCC signal generated by the TMCC generation unit.

  An OFDM signal transmission apparatus according to claim 5 is the OFDM signal transmission apparatus according to any one of claims 1 to 4, comprising a plurality of transmission antennas, and transmitted via the plurality of transmission antennas. A MIMO transmission system is configured with an OFDM signal receiving apparatus that receives the OFDM signal.

  Furthermore, the OFDM signal receiving apparatus according to claim 6 receives an OFDM signal including partial reception data and fixed reception data in a band having a segment structure including a partial reception segment area and a fixed reception segment area. In the OFDM signal receiving apparatus, a reception unit that receives the OFDM signal with an area including the partial reception segment area and a part of the fixed reception segment area as a partial reception bandwidth, and received by the reception section FFT on the OFDM signal at a size corresponding to the partial reception bandwidth, and an FFT unit for converting a time domain signal to a frequency domain signal, and the frequency domain signal converted by the FFT unit, Demodulator that demodulates using transmission path characteristics and generates demodulated signal of OFDM frame corresponding to the partial reception bandwidth From the demodulated signal of the OFDM frame generated by the demodulator, a deinterleave unit that performs frequency deinterleaving, and from the demodulated signal of the OFDM frame that has been frequency deinterleaved by the deinterleave unit, A demultiplexer that demultiplexes the demodulated signal of the OFDM frame corresponding to the segment area for reception, and a demodulated signal of the OFDM frame that corresponds to the segment area for partial reception separated by the demultiplexer, And a deframing unit that generates a demodulated signal corresponding to the data carrier of the data.

  An OFDM signal receiving apparatus according to claim 7 is the OFDM signal receiving apparatus according to claim 6, wherein a part of the fixed reception segment area included in the partial reception bandwidth is divided into predetermined segment positions. Or a region with a predetermined carrier position in the segment as a delimiter.

  Further, the OFDM signal receiving apparatus according to claim 8 is the OFDM signal receiving apparatus according to claim 6 or 7, wherein the frequency deinterleaving by the deinterleaving unit is performed by segment frequency deinterleaving or carrier frequency deinterleaving. It is characterized by that.

  An OFDM signal receiving apparatus according to claim 9 is the OFDM signal receiving apparatus according to any one of claims 6 to 8, further comprising: a TMCC signal from the frequency domain signal converted by the FFT unit. A TMCC extracting unit for extracting, and the deinterleaving unit performs the frequency deinterleaving on the demodulated signal of the OFDM frame based on information on the frequency interleaving included in the TMCC signal extracted by the TMCC extracting unit. It is characterized by applying.

  An OFDM signal receiving apparatus according to claim 10 is the OFDM signal receiving apparatus according to any one of claims 6 to 9, further comprising a plurality of receiving antennas, wherein the OFDM signal is transmitted via a plurality of transmitting antennas. A MIMO transmission system is configured with an OFDM signal transmitting apparatus for transmission.

  As described above, according to the present invention, by performing wideband frequency interleaving, it is possible to improve the frequency interleaving effect in ISDB-T partial reception, and to improve the reception characteristics.

It is a block diagram which shows the structural example of the OFDM signal transmitter by embodiment of this invention. It is a block diagram which shows the structural example of the OFDM signal receiver for partial reception by embodiment of this invention. It is a block diagram which shows the structural example of the OFDM signal transmitter by other embodiment of this invention. It is a block diagram which shows the structural example of the OFDM signal receiver for partial reception by other embodiment of this invention. It is a figure which shows the example of 33 segment structure in the next-generation digital terrestrial broadcasting, partial reception bandwidth (gamma), etc. It is a figure which shows the example of the frequency interleaving of the segment unit in Example 2. FIG. It is a figure which shows the example of the frequency interleaving of the carrier unit in Example 3. FIG. It is a figure which shows the segment structure of ISDB-T.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the present invention, data set in a bandwidth (partial reception bandwidth γ) composed of a partial reception segment area α and a part of the fixed reception segment area β is subjected to frequency interleaving and frequency deinterleaving. It is characterized by that. The part of the fixed reception segment area β is, for example, an area with a predetermined segment position as a delimiter or an area with a predetermined carrier position in a segment as a delimiter.

  Specifically, with respect to transmission / reception of data for partial reception, the OFDM signal transmitting apparatus performs frequency interleaving on data set within the partial reception bandwidth γ and transmits a broadcast wave of the OFDM signal. The OFDM signal receiving apparatus receives a broadcast wave of the OFDM signal, performs frequency deinterleaving on the data set within the partial reception bandwidth γ, and restores the original partial reception data.

  As a result, wideband frequency interleaving is performed, and in the ISDB-T partial reception, the effect of frequency interleaving can be improved, and reception characteristics can be improved.

[33 segment structure and partial reception bandwidth γ, etc.]
FIG. 5 is a diagram illustrating an example of a 33-segment structure and a partial reception bandwidth γ in the next-generation terrestrial digital broadcasting. The horizontal axis indicates the frequency. This 33 segment structure is currently under consideration.

  In the next-generation terrestrial digital broadcasting, the bandwidth (6000/36 = 166.66 kHz) obtained by dividing the 6 MHz band per channel into 36 is defined as one segment, and 33 or 35 segments of the 36 segments are used. To be considered.

  In FIG. 5, in the 33 segment structure subjected to hierarchical synthesis, a segment reception segment area α of 3 segments is arranged at the center of the band of one channel. Also, 15 segments of fixed reception segment areas β are arranged on both sides of the partial reception segment area α.

  A band consisting of a segment reception segment area α of 3 segments and a fixed reception segment area β2 of 6 segments arranged on both sides of the segment reception segment area α of the fixed reception segment area β is expressed as a partial reception bandwidth. Let γ. Data set in this partial reception bandwidth γ is a target of frequency interleaving and frequency deinterleaving. As the partial reception bandwidth γ, as shown in the example of FIG. 5, there is a case where an area with a segment as a unit and a predetermined segment position as a delimiter is set, or a predetermined carrier in a segment with a carrier as a unit. In some cases, an area with a position as a delimiter is set.

  In FIG. 5, the partial reception bandwidth γ is set in units of segments, and the number of segments is 9 (= 36/4). The number of segments of the partial reception bandwidth γ corresponds to the number that can be received by the number of FFT points of ¼ at the time of receiving one channel in an OFDM signal receiving apparatus for partial reception described later. That is, the partial reception OFDM signal receiving apparatus to be described later does not need to receive the broadcast wave of the OFDM signal of all channels (6 MHz bandwidth), and can perform demodulation with a reduced number of FFT points.

  Of the fixed reception segment area β, areas other than the fixed reception area β2 are defined as fixed reception areas β1. That is, the fixed reception segment area β is composed of a fixed reception area β1 on the end side of the channel and a fixed reception area β2 on the partial reception side.

[OFDM signal transmitter]
First, an OFDM signal transmission apparatus according to an embodiment of the present invention will be described. FIG. 1 is a block diagram illustrating a configuration example of an OFDM signal transmission apparatus according to an embodiment of the present invention. This OFDM signal transmission apparatus 1-1 includes a transmission antenna 10, carrier modulation units 11 and 12, a separation unit 13, interleaving units 14 and 15, a framing unit 16, an IFFT unit 17, and a transmission unit 18. FIG. 1 shows only the components and data directly related to the present invention, and the components and data not directly related are omitted. The same applies to FIGS. 2 to 4 described later.

  The carrier modulation unit 11 receives the partial reception data A, modulates the data A with a preset modulation scheme parameter, and outputs a data carrier (partial reception data carrier) a to the interleaving unit 14. . The data A corresponds to the partial reception segment area α shown in FIG. 5, but is not necessarily transmitted in the band of the partial reception segment area α by the interleaving unit 14 described later.

  The carrier modulation unit 12 receives the fixed reception data B, modulates the data B with a preset modulation method parameter, and outputs the data carrier (fixed reception data carrier) b to the separation unit 13. . The data carrier b corresponds to the fixed reception segment area β shown in FIG. 5, but is not necessarily transmitted in the band of the fixed reception segment area β by the interleaving unit 14 described later.

  The separation unit 13 receives the data carrier b from the carrier modulation unit 12 and separates the data carrier b into the data carrier b1 and the data carrier b2 according to a preset separation rule. Then, the separation unit 13 outputs the data carrier b1 to the interleaving unit 15 and outputs the data carrier b2 to the interleaving unit 14.

  The data carrier b1 corresponds to the fixed reception area β1 on the end side of the channel shown in FIG. 5, and is transmitted in the band of the fixed reception area β1. The data carrier b2 corresponds to the fixed reception area β2 on the partial reception side illustrated in FIG. 5, but is not always transmitted in the band of the fixed reception area β2 by the interleave unit 14 described later.

  The separation rule is the separation target when separating the data carrier b corresponding to the fixed reception segment area β into the data carrier b1 corresponding to the fixed reception area β1 and the data carrier b2 corresponding to the fixed reception area β2. Information for specifying the fixed reception area β2 is set in advance. Specifically, the separation rule is information defining the number of segments, the position, the segment number, the band, etc. of the fixed reception area β2.

  The interleaving unit 14 inputs the data carrier a from the carrier modulation unit 11 and the data carrier b2 from the separation unit 13. The interleaving unit 14 performs interleaving such as frequency interleaving on the data carrier a corresponding to the partial reception segment area α and the data carrier b2 corresponding to the fixed reception area β2 in accordance with a preset interleaving rule. Interleaving section 14 outputs the interleaved data carrier (a + b2) ^ to framing section 16.

  The interleaving rule is information that defines the type, target, position, content, and the like of interleaving, and is set in advance.

  That is, the interleave unit 14 performs frequency interleaving or the like on the data carriers a and b2 corresponding to the segments of the partial reception segment region α and the fixed reception region β2 within the partial reception bandwidth γ shown in FIG.

  In addition to the frequency interleaving, the interleaving unit 14 may perform other processing such as time interleaving and bit interleaving.

  The interleaving unit 15 receives the data carrier b1 from the demultiplexing unit 13, and performs interleaving such as frequency interleaving on the data carrier b1 corresponding to the fixed reception area β1 according to a preset interleaving rule. Interleaving section 15 then outputs interleaved data carrier b1 ^ to framing section 16.

  The framing unit 16 receives the data carrier (a + b2) ^ from the interleaving unit 14 and the data carrier b1 ^ from the interleaving unit 15. The framing unit 16 then sets the data carrier (a + b2) ^ to the partial reception segment area α and the fixed reception area β2 having the partial reception bandwidth γ, and receives the data carrier b1 ^ etc. An OFDM frame is configured with a pilot signal for transmission path estimation, etc., so as to be set in the use area β1. The framing unit 16 outputs the OFDM frame signal to the IFFT unit 17.

  The IFFT unit 17 inputs an OFDM frame signal from the framing unit 16. Then, the IFFT unit 17 performs an IFFT on the OFDM frame signal (the OFDM frame carrier position and symbol position signals corresponding to the partial reception segment area α and the fixed reception segment area β), and converts the frequency domain signal into the time domain. Convert to a signal. The IFFT unit 17 outputs a time domain signal to the transmission unit 18.

  The transmission unit 18 receives a time domain signal from the IFFT unit 17 and performs GI (guard interval) addition, D / A conversion, LFP (low pass filter) filter processing, frequency conversion processing, and the like on the time domain signal. Apply. Then, the transmitter 18 transmits the broadcast wave of the OFDM signal via the transmission antenna 10 in the band of the partial reception segment area α and the fixed reception segment area β shown in FIG.

  The frequency interleaving method may use a random number, or may use a method according to a certain rule. The configuration shown in FIG. 1 realizes transmission and reception of two layers of partial reception and fixed reception shown in FIG. 5. However, transmission and reception of three layers can be realized by adding one system. it can.

  As described above, according to the OFDM signal transmission device 1-1 according to the embodiment of the present invention, the separation unit 13 separates the data carrier b into the data carrier b1 and the data carrier b2. The interleaving unit 14 performs frequency interleaving or the like on the data carriers a and b2 corresponding to the partial reception segment area α and the fixed reception area β2 within the partial reception bandwidth γ.

  Thereby, an OFDM signal receiving apparatus for partial reception described later receives a broadcast wave subjected to frequency interleaving or the like within the partial reception bandwidth γ, and performs frequency deinterleaving within the partial reception bandwidth γ. The original partial reception data A can be restored.

  Therefore, by performing wideband frequency interleaving, the effect of frequency interleaving can be improved and reception characteristics can be improved in partial reception of ISDB-T.

[OFDM signal receiver]
Next, an OFDM signal receiving apparatus for partial reception according to an embodiment of the present invention will be described. FIG. 2 is a block diagram illustrating a configuration example of an OFDM signal receiving apparatus for partial reception according to an embodiment of the present invention. The OFDM signal receiving device 2-1 includes a receiving antenna 20, a receiving unit 21, an FFT unit 22, a demodulating unit 23, a deinterleave unit 24, a demultiplexing unit 25, and a deframe unit 26.

  The reception unit 21 corresponds to the transmission unit 18 illustrated in FIG. 1 and receives the broadcast wave of the OFDM signal from the OFDM signal transmission device 1-1 via the reception antenna 20. Then, the receiving unit 21 performs processing such as frequency conversion, A / D conversion, and GI removal on the received signal, and outputs the OFDM signal to the FFT unit 22.

  The FFT unit 22 corresponds to the IFFT unit 17 shown in FIG. 1 and inputs an OFDM signal from the receiving unit 21. Then, the FFT unit 22 performs FFT on the OFDM signal with a size corresponding to the partial reception bandwidth γ (the partial reception segment region α and the fixed reception region β2), and converts the time domain signal into the frequency domain signal. Convert. As a result, signals in the frequency domain of the partial reception segment area α and the fixed reception area β2 are obtained.

  The FFT unit 22 outputs the frequency domain signal (the OFDM frame carrier position and symbol position signals set in the partial reception segment area α and the fixed reception area β 2) to the demodulation unit 23.

  The demodulation unit 23 receives the frequency domain signal from the FFT unit 22, demodulates (equalizes) the frequency domain signal using the channel characteristics estimated by the channel estimation unit (not shown), and demodulates the OFDM frame demodulated signal. (The demodulated signals of the partial reception segment area α and the fixed reception area β2) are generated. The demodulator 23 outputs the demodulated signal of the OFDM frame to the deinterleaver 24.

  The deinterleaving unit 24 corresponds to the interleaving unit 14 shown in FIG. 1 and receives the demodulated signal of the OFDM frame from the demodulating unit 23. Then, the deinterleave unit 24 performs reverse processing of interleaving, that is, deinterleaving such as frequency deinterleaving, on the demodulated signal in accordance with a preset deinterleaving rule. The deinterleaving unit 24 outputs the demodulated signal of the OFDM frame after deinterleaving to the demultiplexing unit 25.

  The demodulated signal of the OFDM frame after deinterleaving is the demodulated signal of the OFDM frame corresponding to the data carrier a of the partial reception segment area α and the demodulated signal of the OFDM frame corresponding to the data carrier b2 of the fixed reception area β2. .

  The deinterleaving rule is the reverse of the above-described interleaving rule. Specifically, the deinterleaving rule is information defining the deinterleaving type, target, position, content, etc., and is set in advance.

  The demultiplexer 25 receives the demodulated signal of the OFDM frame after deinterleaving from the deinterleaver 24. The demultiplexer 25 then demodulates the OFDM frame demodulated signal corresponding to the data carrier a in the partial reception segment area α, which is an area other than the fixed reception area β2, from the OFDM frame demodulated signal in accordance with a predetermined demultiplexing rule. Isolate. Separating section 25 outputs the demodulated signal of the OFDM frame corresponding to data carrier a in partial reception segment area α to deframing section 26.

  As described above, information for specifying the fixed reception area β2 is set in advance in the separation rule. Specifically, the separation rule is information defining the number of segments, the position, the segment number, the band, etc. of the fixed reception area β2. According to the separation rule, the partial reception segment area α can be separated from the partial reception segment area α and the fixed reception area β2. The OFDM signal receiving device 2-1 uses the same separation rule as that used by the OFDM signal transmitting device 1-1.

  The deframing unit 26 corresponds to the framing unit 16 shown in FIG. 1 and inputs a demodulated signal of an OFDM frame corresponding to the data carrier a of the partial reception segment area α from the demultiplexing unit 25. The deframing unit 26 deframes the demodulated signal of the OFDM frame corresponding to the data carrier a in the partial reception segment area α, and generates the demodulated signal a ′ corresponding to the data carrier a in the partial reception segment area α. Generate and output.

  As described above, according to the OFDM signal receiving device 2-1 according to the embodiment of the present invention, the OFDM signal broadcast wave is received from the OFDM signal transmitting device 1-1, and the FFT unit 22 FFT is performed with a size corresponding to the segment area α for reception and the area β2 for fixed reception, and frequency domain signals of the segment area α for partial reception and the area β2 for fixed reception are generated.

  The demodulator 23 demodulates (equalizes) the frequency domain signal, and the deinterleaver 24 deinterleaves the demodulated signal of the OFDM frame, such as frequency deinterleave.

  The demultiplexing unit 25 demultiplexes the OFDM frame demodulated signal corresponding to the data carrier a in the partial reception segment region α from the deinterleaved OFDM frame demodulated signal. The deframing unit 26 deframes the demodulated signal of the OFDM frame corresponding to the data carrier a of the partial reception segment area α, and generates the demodulated signal a ′ corresponding to the data carrier a.

  Thereby, the broadcast wave of the OFDM signal subjected to wideband frequency interleaving is received, and the wideband frequency deinterleaving is performed, so that the effect of frequency interleaving can be improved in the partial reception of ISDB-T. The characteristics can be improved.

  Hereinafter, the OFDM signal transmission apparatus 1-1 illustrated in FIG. 1 and the OFDM signal reception apparatus 2-1 illustrated in FIG.

  The first embodiment is an example in which frequency interleaving is performed on data set in a segment having a partial reception bandwidth γ. The second embodiment is an example in which frequency interleaving in units of segments is performed on data set in a segment having a partial reception bandwidth γ. The third embodiment is an example in which frequency interleaving in units of carriers is performed on data set in a segment having a partial reception bandwidth γ.

[Example 1]
First, Example 1 will be described. As described above, the first embodiment is an example in which frequency interleaving is performed on data set in the segment of the partial reception bandwidth γ. The frequency interleaving according to the first embodiment is a wide concept including a segment unit, a carrier unit, a carrier rotation, and the like.

  As shown in FIG. 5, it is assumed that a partial reception bandwidth γ of 9 segments in total is set in advance, where the number of segments in the partial reception segment area α is 3 and the number of segments in the fixed reception area β2 is 6. .

(Transmitter / Example 1)
In the interleaving rule of the first embodiment, frequency interleaving is set in advance as the type of interleaving. In addition, the interleaving unit 14 includes a total of 9 segments of the partial reception bandwidth γ including three segments of the partial reception segment region α and six segments of the fixed reception region β2 as frequency interleaving targets, the position and content of each segment, etc. Various information is set in advance. In the interleaving unit 15, various information such as 24 segments of the fixed reception area β 1, the position and content of each segment are set in advance as frequency interleaving targets.

  In the OFDM signal transmitting apparatus 1-1 shown in FIG. 1, the interleaving unit 14 performs frequency interleaving on the nine-segment data carriers a and b2 having the partial reception bandwidth γ according to this interleaving rule.

  The interleaving unit 15 performs frequency interleaving on the 24-segment data carrier b1 in the fixed reception area β1 in accordance with this interleaving rule.

(Receiver / Example 1)
The receiving unit 21 of the OFDM signal receiving device 2-1 illustrated in FIG. 2 receives an OFDM signal broadcast wave from the OFDM signal transmitting device 1-1 of the first embodiment.

  The deinterleaving rule of the first embodiment corresponds to the interleaving rule of the first embodiment, and frequency deinterleaving is preset as the type of deinterleaving. In addition, as a frequency deinterleave target, a total of 9 segments of partial reception bandwidth γ consisting of 3 segments of partial reception segment region α and 6 segments of fixed reception region β2, and various information such as the position and content of each segment are stored in advance. Is set.

  The deinterleaving unit 24 performs frequency deinterleaving on the demodulated signals in the partial reception segment area α and the fixed reception area β2 in accordance with the deinterleaving rule. As a result, the demodulation signal of the OFDM frame corresponding to the data carrier a in the partial reception segment area α and the demodulation signal of the OFDM frame corresponding to the data carrier b2 in the fixed reception area β2 are generated.

  As described above, according to the first embodiment, the segment of the partial reception bandwidth γ composed of the partial reception segment region α and the fixed reception region β2 is set as the target of frequency interleaving and frequency deinterleaving. As a result, since a segment having a wider band than the conventional one is targeted, the effect of frequency interleaving can be improved, and reception characteristics can be improved.

[Example 2]
Next, Example 2 will be described. As described above, the second embodiment is an example in which frequency interleaving in units of segments is performed on data set in a segment having a partial reception bandwidth γ. As in the first embodiment, the partial reception bandwidth γ is as shown in FIG.

(Transmitter / Example 2)
In the interleaving rule of the second embodiment, segment unit frequency interleaving is preset as the type of interleaving. In the interleaving unit 14, various information such as the segment, position, and content of the partial reception bandwidth γ is set in advance as a frequency interleaving target. In the interleaving unit 15, various information such as the segment, position, and content of the fixed reception region β1 is set in advance as a frequency interleaving target.

  In the OFDM signal transmitting apparatus 1-1 shown in FIG. 1, the interleaving unit 14 performs frequency interleaving in units of segments on the nine-segment data carriers a and b2 having the partial reception bandwidth γ according to the interleaving rule.

  The interleaving unit 15 performs frequency interleaving in units of segments on the 24-segment data carrier b1 in the fixed reception area β1 in accordance with this interleaving rule.

  FIG. 6 is a diagram illustrating an example of segment-unit frequency interleaving in the second embodiment. FIG. 6 (1) shows the segment arrangement before frequency interleaving, and FIG. 6 (2) shows the segment arrangement after frequency interleaving. # Indicates a segment number.

  As shown in FIG. 6 (1), before frequency interleaving, segment reception segment area α within partial reception bandwidth γ has segment # 0 in the center and segment # 1 on the left side (lower frequency side). The segment # 2 is arranged on the right side (high frequency side) of the center. In the fixed reception region β2 within the partial reception bandwidth γ, segments # 7, # 5, and # 3 are arranged on the left side of the partial reception segment region α from the low frequency to the high frequency. Also, segments # 4, # 6, and # 8 are arranged on the right side of the partial reception segment area α.

  In the fixed reception area β1 other than the partial reception bandwidth γ, segments # 33, # 31,..., # 13, # 11 are arranged on the left side of the partial reception bandwidth γ from the low frequency to the high frequency. Has been placed. Also, segments # 10, # 12,..., # 30, # 32 are arranged on the right side of the partial reception bandwidth γ.

  The segment arrangement of the partial reception bandwidth γ shown in FIG. 6 (1) is performed according to the interleave rule in the interleaving unit 14 by segment-unit frequency interleaving for nine segments of the partial reception bandwidth γ. The segment arrangement shown in FIG.

  As shown in FIG. 6 (2), after frequency interleaving, the partial reception segment area α within the partial reception bandwidth γ has segment # 0 at the center, segment # 6 at the center left, and segment at the center right. # 4 is arranged. In the fixed reception area β2 within the partial reception bandwidth γ, segments # 1, # 3, and # 7 are arranged on the left side of the partial reception segment area α from the low frequency to the high frequency. Also, segments # 5, # 2, and # 8 are arranged on the right side of the partial reception segment area α.

  Further, according to the interleaving rule in the interleave unit 15, the segment arrangement of the fixed reception region β1 shown in FIG. 6 (1) by the segment unit frequency interleaving for the 24 segments of the fixed reception region β1 is shown in FIG. The segment arrangement shown in 2) is changed.

  As shown in FIG. 6 (2), after frequency deinterleaving, the fixed reception area β1 has segments # 33, # 19,... On the left side of the partial reception bandwidth γ from low frequency to high frequency. ..., # 32 and # 18 are arranged. Also, segments # 30, # 20,..., # 21, # 31 are arranged on the right side of the partial reception bandwidth γ.

(Receiver / Example 2)
The receiving unit 21 of the OFDM signal receiving apparatus 2-1 illustrated in FIG. 2 receives an OFDM signal broadcast wave from the OFDM signal transmitting apparatus 1-1 according to the second embodiment.

  The deinterleaving rule according to the second embodiment corresponds to the interleaving rule according to the second embodiment, and a segment unit frequency deinterleaving is set in advance as a deinterleaving type. In addition, as the frequency deinterleave target, various pieces of information such as the segment, position, and content of the partial reception bandwidth γ are set in advance.

  The deinterleaving unit 24 performs frequency deinterleaving in units of segments on the demodulated signals in the partial reception segment area α and the fixed reception area β2 according to the deinterleaving rule. As a result, the demodulation signal of the OFDM frame corresponding to the data carrier a in the partial reception segment area α and the demodulation signal of the OFDM frame corresponding to the data carrier b2 in the fixed reception area β2 are generated.

  In the example of FIG. 6, the partial reception bandwidth shown in FIG. 6 (2) is obtained by the segment-unit frequency deinterleaving for nine segments of the partial reception bandwidth γ in accordance with the deinterleaving rule in the deinterleaving unit 24. The segment arrangement of γ returns to the segment arrangement shown in FIG.

  As described above, according to the second embodiment, the segment having the partial reception bandwidth γ composed of the partial reception segment region α and the fixed reception region β2 is set as the target of frequency interleaving and frequency deinterleaving in units of segments. did. As a result, since a segment having a wider band than the conventional one is targeted, the effect of frequency interleaving can be improved, and reception characteristics can be improved.

  In addition, although Example 2 is an example which performs the frequency interleaving of a segment unit, you may make it carry out carrier randomization within a segment, and may perform time interleaving.

Example 3
Next, Example 3 will be described. As described above, the third embodiment is an example in which frequency interleaving in units of carriers is performed on data set in the segment of the partial reception bandwidth γ. As in the first embodiment, the partial reception bandwidth γ is as shown in FIG.

(Transmitter / Example 3)
In the interleaving rule of the third embodiment, frequency interleaving for each carrier is set in advance as the type of interleaving. In the interleaving unit 14, various information such as the segment, position, and content of the partial reception bandwidth γ is set in advance as a frequency interleaving target. In the interleaving unit 15, various information such as the segment, position, and content of the fixed reception region β1 is set in advance as a frequency interleaving target.

  In the OFDM signal transmitting apparatus 1-1 shown in FIG. 1, the interleaving unit 14 performs frequency interleaving for each of the nine-segment data carriers a and b2 having the partial reception bandwidth γ in accordance with this interleaving rule.

  The interleaving unit 15 performs frequency interleaving in units of carriers on the 24-segment data carrier b1 in the fixed reception area β1 in accordance with the interleaving rule.

  FIG. 7 is a diagram illustrating an example of frequency interleaving in units of carriers in the third embodiment. FIG. 7 (1) shows the carrier arrangement before frequency interleaving, and FIG. 7 (2) shows the carrier arrangement after frequency interleaving.

  As shown in FIG. 7 (1), before frequency interleaving, the carrier indicated by the solid line arrow is arranged in the partial reception segment area α within the partial reception bandwidth γ, and the dotted line is shown in the fixed reception area β2. Carriers indicated by arrows are arranged. A carrier (not shown) is also arranged in the fixed reception area β1 other than the partial reception bandwidth γ.

  The carrier arrangement of the partial reception bandwidth γ shown in FIG. 7 (1) is shown in FIG. 7 (1) by frequency interleaving in units of carriers for nine segments of the partial reception bandwidth γ according to the above-described interleaving rule in the interleave unit 14. The carrier arrangement shown in 2) is changed.

  As shown in FIG. 7 (2), after frequency interleaving, the carrier indicated by the solid arrow and the carrier indicated by the dotted arrow are arranged in the partial reception segment region α within the partial reception bandwidth γ. Also in the fixed reception area β2 within the partial reception bandwidth γ, carriers indicated by solid arrows and carriers indicated by dotted arrows are arranged.

  In accordance with the above-described interleaving rule in the interleave unit 15, the carrier arrangement of the fixed reception region β1 is changed by the carrier unit frequency interleaving for the 24 segments of the fixed reception region β1.

(Receiver / Example 3)
The receiving unit 21 of the OFDM signal receiving device 2-1 illustrated in FIG. 2 receives an OFDM signal broadcast wave from the OFDM signal transmitting device 1-1 of the third embodiment.

  In the deinterleaving rule of the third embodiment, frequency deinterleaving for each carrier is set in advance as the deinterleaving type. In addition, as the frequency deinterleave target, various pieces of information such as the segment, position, and content of the partial reception bandwidth γ are set in advance.

  The deinterleaving unit 24 performs frequency deinterleaving for each carrier on the demodulated signals in the partial reception segment area α and the fixed reception area β2 in accordance with this deinterleaving rule. As a result, the demodulation signal of the OFDM frame corresponding to the data carrier a in the partial reception segment area α and the demodulation signal of the OFDM frame corresponding to the data carrier b2 in the fixed reception area β2 are generated.

  In the example of FIG. 7, the partial reception bandwidth shown in FIG. 7 (2) is obtained by frequency deinterleaving in units of carriers for nine segments of the partial reception bandwidth γ in accordance with the deinterleaving rule in the deinterleaving unit 24. The carrier arrangement of γ returns to the carrier arrangement shown in FIG.

  As described above, according to the third embodiment, the segment having the partial reception bandwidth γ including the partial reception segment region α and the fixed reception region β2 is subjected to frequency interleaving and frequency deinterleaving in units of carriers. did. As a result, since a segment having a wider band than the conventional one is targeted, the effect of frequency interleaving can be improved, and reception characteristics can be improved.

  The third embodiment is an example in which frequency interleaving is performed on a carrier basis. However, carrier randomization may be performed within a segment, and time interleaving may be performed.

[Other OFDM signal transmitters]
Next, an OFDM signal transmission apparatus according to another embodiment of the present invention will be described. FIG. 3 is a block diagram illustrating a configuration example of an OFDM signal transmission apparatus according to another embodiment of the present invention. This OFDM signal transmission device 1-2 further includes a TMCC generation unit 19 in addition to the transmission antenna 10 and the components from the carrier modulation units 11 and 12 to the transmission unit 18 shown in FIG.

  The components from the transmission antenna 10 and the carrier modulation units 11 and 12 to the transmission unit 18 have already been described with reference to FIG. The framing unit 16 receives a TMCC signal from a TMCC generation unit 19 to be described later, and includes the TMCC signal so that the TMCC signal is set in each of the partial reception segment area α and the fixed reception segment area β. Frame.

  The TMCC generation unit 19 modulates the separation rule, the interleave rule, the partial reception band information, and the like to generate a TMCC signal. Then, the TMCC generation unit 19 outputs a TMCC signal including the separation rule, the interleave rule, and the partial reception band information to the framing unit 16. As a result, the framing unit 16 performs framing so that the TMCC signal is set in each of the partial reception segment area α and the fixed reception segment area β.

  As described above, the separation rule is information for specifying the fixed reception area β2 to be separated, specifically, information defining the number of segments, the position, the segment number, the band, etc. of the fixed reception area β2. . The interleave rule is information that defines the type, target, position, content, and the like of interleave.

  The partial reception band information is information about the partial reception bandwidth γ, such as the number of segments, the position, the segment number, and the bandwidth of the partial reception segment area α and the fixed reception area β2, and the partial reception segment area constituting the channel. Information on α and the fixed reception segment area β is also included.

  As described above, according to the OFDM signal transmission apparatus 1-2 according to another embodiment of the present invention, a TMCC signal including a separation rule, an interleaving rule, and partial reception band information is transmitted. As a result, the OFDM signal receiving apparatus 2-2, which will be described later, determines the partial reception band such as the separation target, the type of deinterleaving that is the reverse processing of interleaving, etc. The number of segments with the width γ can be determined.

  Therefore, in addition to the same effects as those of the OFDM signal transmitting apparatus 1-1, it is possible to cause the OFDM signal receiving apparatus 2-2, which will be described later, to realize processing applied to the separation rule, interleave rule, etc. of the OFDM signal transmitting apparatus 1-2. it can.

[Other OFDM signal receivers]
Next, an OFDM signal receiving apparatus according to another embodiment of the present invention will be described. FIG. 4 is a block diagram illustrating a configuration example of an OFDM signal receiving apparatus according to another embodiment of the present invention. This OFDM signal receiving apparatus 2-2 includes a TMCC extracting unit 27 and a TMCC demodulating unit 28 in addition to the receiving antenna 20 and the components from the receiving unit 21 to the deframing unit 26 shown in FIG.

  The components from the receiving antenna 20 and the receiving unit 21 to the deframing unit 26 have already been described with reference to FIG.

  The FFT unit 22 receives partial reception band information from a TMCC demodulation unit 28, which will be described later, and performs FFT processing with a size corresponding to the partial reception segment area α and the fixed reception area β2 indicated by the partial reception band information. . Further, the demodulator 23 receives partial reception band information from a TMCC demodulator 28 (to be described later), and demodulates the signal in the frequency domain of the partial reception segment area α and the fixed reception area β2 indicated by the partial reception band information. I do.

  The deinterleaving unit 24 receives an interleaving rule from a TMCC demodulating unit 28, which will be described later, and performs a deinterleaving process according to a deinterleaving rule opposite to the interleaving rule. Further, the separation unit 25 receives a separation rule from a TMCC demodulation unit 28 described later, and performs separation processing according to the separation rule.

  The TMCC extraction unit 27 inputs the frequency domain signal (the signal of the carrier position and the symbol position of the OFDM frame corresponding to the partial reception segment area α and the fixed reception area β 2) from the FFT unit 22. Then, the TMCC extraction unit 27 extracts a TMCC signal including a separation rule, an interleaving rule, and partial reception band information from the frequency domain signal, and outputs the TMCC signal to the TMCC demodulation unit 28.

  The TMCC demodulation unit 28 receives the TMCC signal from the TMCC extraction unit 27 and demodulates the TMCC signal, thereby generating a separation rule, an interleaving rule, and partial reception band information. Then, the TMCC demodulation unit 28 outputs the partial reception band information to the FFT unit 22 and the demodulation unit 23, outputs the interleave rule to the deinterleave unit 24, and outputs the separation rule to the separation unit 25.

  As a result, the FFT unit 22 performs FFT processing using the partial reception band information, and the demodulation unit 23 performs demodulation processing using the partial reception band information. Further, the deinterleaving unit 24 performs deinterleaving processing using a deinterleaving rule opposite to the interleaving rule, and the separating unit 25 performs separation processing using the separation rule.

  As described above, according to the OFDM signal receiving apparatus 2-2 according to another embodiment of the present invention, a TMCC signal is received, and a separation rule, an interleave rule, and partial reception band information are generated from the TMCC signal. Thereby, from this information, it is possible to determine the number of segments of the partial reception bandwidth γ and the like, such as the separation target, the type of deinterleaving that is the reverse processing of interleaving, and the like. Then, using these pieces of information, FFT, demodulation, deinterleaving, and separation processing are performed.

  Therefore, in addition to the same effects as those of the OFDM signal receiving apparatus 2-1, processing applied to the OFDM signal transmitting apparatus 1-2 can be realized using the TMCC signal received from the OFDM signal transmitting apparatus 1-2.

  The present invention has been described with reference to the first to third embodiments. However, the present invention is not limited to the first to third embodiments, and various modifications can be made without departing from the technical idea thereof. For example, in FIGS. 5 to 7, in the structure of 33 segments per channel, the partial reception bandwidth γ is set to be composed of 3 segments of the partial reception segment area α and 6 segments of the fixed reception area β2. Yes. However, the partial reception bandwidth γ is an example, and the present invention is not limited to this.

  For example, the partial reception bandwidth γ is set to include a region up to a predetermined carrier position in a predetermined segment among six segments of the partial reception segment region β in addition to the three segments of the partial reception segment region α. You may be made to do. That is, the partial reception bandwidth γ does not necessarily have to be set in the segment unit area (area delimited by the segment), but may be set in the area delimited by the carrier position in the segment. Good.

  In addition, the OFDM signal transmission apparatuses 1-1 and 1-2 and the OFDM signal reception apparatuses 2-1 and 2-2 illustrated in FIGS. 1 to 4 include one transmission antenna 10 on the transmission side and the reception side. Also, one receiving antenna 20 is provided. On the other hand, the present invention is also applicable to a MIMO (Multiple Input Multiple Output) transmission system having a plurality of transmission antennas on the transmission side and a plurality of reception antennas on the reception side. In this case, the transmission-side OFDM signal transmission apparatus includes a plurality of transmission systems shown in FIGS. 1 and 3 corresponding to the plurality of transmission antennas. The receiving-side OFDM signal receiving apparatus performs MIMO demodulation on each received signal received via a plurality of receiving antennas.

DESCRIPTION OF SYMBOLS 1 OFDM signal transmitter 2 OFDM signal receiver 10 Transmission antenna 11, 12 Carrier modulation part 13 Separation part 14, 15 Interleaving part 16 Framing part 17 IFFT part 18 Transmission part 19 TMCC generation part 20 Reception antenna 21 Reception part 22 FFT part 23 Demodulator 24 Deinterleaver 25 Separator 26 Deframer 27 TMCC Extractor 28 TMCC Demodulator

Claims (10)

In an OFDM signal transmitting apparatus that transmits an OFDM signal including data for partial reception and data for fixed reception in a band of a segment structure composed of a segment area for partial reception and a segment area for fixed reception,
A carrier modulation unit that modulates the data for partial reception to generate a data carrier for partial reception, and modulates the data for fixed reception to generate a data carrier for fixed reception;
An area consisting of the partial reception segment area and a part of the fixed reception segment area as a partial reception bandwidth,
The fixed reception data carrier generated by the carrier modulation unit is a first fixed reception data carrier corresponding to a region other than a part of the fixed reception segment region in the fixed reception segment region, and A separation unit that separates into a second fixed reception data carrier corresponding to a part of the fixed reception segment area;
While performing frequency interleaving on the partial reception data carrier generated by the carrier modulation unit and the second fixed reception data carrier separated by the separation unit,
An interleaving unit that performs frequency interleaving on the first fixed reception data carrier separated by the separating unit;
The partial reception data carrier and the second fixed reception data carrier subjected to the frequency interleaving by the interleaving unit are set in the partial reception bandwidth region, and the interleaving unit sets the frequency. A framing unit that configures an OFDM frame so that the interleaved first fixed reception data carrier is set in an area other than a part of the fixed reception segment area in the fixed reception segment area When,
IFFT unit that performs IFFT on the signal of the OFDM frame configured by the framing unit and converts the signal in the frequency domain into a signal in the time domain;
A transmission unit that transmits the OFDM signal via a transmission antenna in a band of a segment structure including the partial reception segment region and the fixed reception segment region, for the time domain signal converted by the IFFT unit When,
An OFDM signal transmitting apparatus comprising: The OFDM signal transmission apparatus according to claim 1, wherein
A part of the fixed reception segment area included in the partial reception bandwidth is an area with a predetermined segment position as a delimiter or an area with a predetermined carrier position in a segment as a delimiter OFDM signal transmitter. The OFDM signal transmission apparatus according to claim 1 or 2,
The OFDM signal transmitting apparatus, wherein the frequency interleaving by the interleaving unit is a segment unit frequency interleave or a carrier unit frequency interleave. In the OFDM signal transmission device according to any one of claims 1 to 3,
And a TMCC generation unit that generates a TMCC signal including information on the partial reception bandwidth and information on the frequency interleaving,
The framing unit
An OFDM signal transmission apparatus comprising an OFDM frame including the TMCC signal generated by the TMCC generation unit. In the OFDM signal transmission device according to any one of claims 1 to 4,
With multiple transmit antennas,
An OFDM signal transmitting apparatus that constitutes a MIMO transmission system with an OFDM signal receiving apparatus that receives the OFDM signal transmitted via the plurality of transmitting antennas. In an OFDM signal receiving apparatus that receives an OFDM signal including partial reception data and fixed reception data in a band of a segment structure including a partial reception segment area and a fixed reception segment area,
An area consisting of the partial reception segment area and a part of the fixed reception segment area as a partial reception bandwidth,
A receiver for receiving the OFDM signal;
FFT for the OFDM signal received by the receiving unit at a size corresponding to the partial reception bandwidth, and converting from a time domain signal to a frequency domain signal;
A demodulator that demodulates the frequency domain signal converted by the FFT unit using transmission path characteristics, and generates a demodulated signal of an OFDM frame corresponding to the partial reception bandwidth;
A deinterleaving unit that performs frequency deinterleaving on the demodulated signal of the OFDM frame generated by the demodulating unit;
A demultiplexer that demultiplexes the demodulated signal of the OFDM frame corresponding to the partial reception segment area from the demodulated signal of the OFDM frame subjected to the frequency deinterleaving by the deinterleaver;
A deframing unit that demodulates an OFDM frame demodulated signal corresponding to the partial reception segment area separated by the demultiplexing unit, and generates a demodulated signal corresponding to a data carrier of the partial reception data;
An OFDM signal receiving apparatus comprising: The OFDM signal receiving apparatus according to claim 6, wherein
A part of the fixed reception segment area included in the partial reception bandwidth is an area with a predetermined segment position as a delimiter or an area with a predetermined carrier position in a segment as a delimiter OFDM signal receiver. The OFDM signal receiving apparatus according to claim 6 or 7,
An OFDM signal receiving apparatus, wherein the frequency deinterleave by the deinterleave unit is a segment unit frequency deinterleave or a carrier unit frequency deinterleave. In the OFDM signal receiving device according to any one of claims 6 to 8,
Further, a TMCC extraction unit that extracts a TMCC signal from the frequency domain signal converted by the FFT unit,
The deinterleaving unit is
An OFDM signal receiving apparatus, wherein the frequency deinterleaving is performed on a demodulated signal of the OFDM frame based on information on frequency interleaving included in the TMCC signal extracted by the TMCC extracting unit. In the OFDM signal receiving device according to any one of claims 6 to 9,
With multiple receiving antennas,
An OFDM signal receiving apparatus constituting a MIMO transmission system with an OFDM signal transmitting apparatus that transmits the OFDM signal via a plurality of transmitting antennas.

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