JP2007005841A - Multi-carrier transmission method, device, and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-carrier transmission system which reduces deterioration of communication quality caused by frequency-selection type fading. <P>SOLUTION: A transmission device 11 divides user information at least into one signal. A sub-carrier of the number of frequency diversity degrees decided according to the transmission path state is assigned to each of the divided signals for performing modulation. Signals obtained are combined and transmitted as a multi-carrier modulated signal. A reception device 12 demodulates the multi-carrier modulated signal from the transmission device 11 by using the same sub-carrier used in the transmission device 11, combines signals constituting a frequency diversity, and connects at least one signal obtained, thereby obtaining a user signal. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a system using a multicarrier transmission system.

  In the multicarrier transmission scheme, information is transmitted by a plurality of carriers (hereinafter referred to as subcarriers) having different frequencies. Various studies have been made on multicarrier transmission systems (see, for example, Patent Documents 1 and 2).

  FIG. 10 is a block diagram showing a configuration of a conventional multicarrier transmission system. Referring to FIG. 10, the multicarrier transmission system includes a transmission device 91 and a reception device 92.

  The transmission device 91 includes a signal input unit 93, an information modulation unit 94, an S / P conversion unit (serial / parallel conversion unit) 95, and a multicarrier modulation unit 96.

  The receiving device 92 includes a multicarrier demodulator 97, a P / S converter 98, an information demodulator 99, and a signal output unit 910.

  The signal input unit 93 gives user information to be transmitted to the information modulation unit 94 as a user information signal.

  The information modulation unit 94 modulates information on the user information signal given from the signal input unit 93 by using a predetermined information modulation method (digital modulation method), and the obtained symbol data is sent to the S / P conversion unit 95. give. Examples of the information modulation method include QPSK and QAM.

  The S / P conversion unit 95 converts the symbol data from the information modulation unit 94 into a parallel signal composed of a plurality of signals, and supplies the parallel signal to the multicarrier modulation unit 96.

  Multicarrier modulation section 96 modulates each of the plurality of parallel signals provided from S / P conversion section 95 using carriers having different frequencies, synthesizes them, and transmits them from the antenna.

  The multicarrier demodulator 97 receives a radio signal from the transmission device 91, demodulates it with a plurality of carriers having the same frequency as that used in the multicarrier modulation unit 96 of the transmission device 91, and converts the demodulated signal to P / The S conversion unit 98 is provided.

  The P / S converter 98 converts the plurality of signals given in parallel from the multicarrier demodulator 97 into serial data, and gives the symbol data obtained thereby to the information demodulator 99.

  The information demodulating unit 99 demodulates the symbol data from the P / S converting unit 98 using the same information modulation method as that used in the information modulating unit 94 of the transmitting apparatus 91 and supplies the demodulated data to the signal output unit 910.

  The signal output unit 910 outputs the signal from the information demodulation unit 99 as a user information signal.

  In wireless communication, a plurality of transmission paths (multipaths) are generated by reflection from various obstacles. The frequency characteristics in the transmission band are distorted due to the difference in propagation delay of each transmission path. This is called frequency selective fading and causes a reduction in communication quality. In mobile communication, there are various obstacles between communication devices, and multipath is inevitable.

When the multi-carrier transmission method is used, user information is transmitted using a plurality of carriers having different frequencies, so that the influence of frequency selective fading can be reduced.
JP 2002-101062 A JP 2002-198930 A

  According to the multicarrier transmission system, the influence of frequency selective fading is reduced. However, if the level variation of the subcarrier due to frequency selective fading is large, the communication quality is deteriorated. In particular, when an information modulation method that requires a large signal-to-noise power (SNR) such as QAM is used, the communication quality is significantly degraded due to frequency selective fading.

  An object of the present invention is to provide a multicarrier transmission system in which deterioration of communication quality due to frequency selective fading is reduced.

To achieve the above object, a multicarrier transmission system of the present invention is a multicarrier transmission system that transmits user information using a plurality of subcarriers having different frequencies from each other,
The user information is divided into at least one signal, and frequency-diversity order subcarriers corresponding to the transmission path state are allocated to each of the divided signals and modulated by the subcarriers, and the obtained signals are combined. And transmitting as a multi-carrier modulation signal,
The multicarrier modulation signal from the transmission device is demodulated by the same subcarrier as that used in the transmission device, and diversity reception is performed using a signal constituting frequency diversity among signals obtained by demodulation, and diversity reception is performed. And a receiving device that combines the at least one signal obtained by the above to obtain the user signal.

  According to the multicarrier transmission system of the present invention, the transmission apparatus changes the frequency diversity order according to the transmission path state and transmits the user information by performing multicarrier modulation, the reception apparatus performs multicarrier inverse modulation, and frequency diversity Each signal is combined to regenerate the user signal.

In addition, the transmission apparatus performs information modulation on the user information with an information modulation scheme selected according to the transmission path state, and then divides the user information into at least one signal, and performs the transmission according to the transmission path state and the information modulation scheme. Each of the signals is modulated with frequency diversity order subcarriers, and combined with the multicarrier modulation signal.
The reception apparatus demodulates the multicarrier modulation signal with the subcarrier, receives diversity reception using the signals constituting frequency diversity, combines signals obtained by diversity reception, and then is used in the transmission apparatus The user signal may be obtained by demodulating information using the same information modulation method.

  According to the multicarrier transmission system of the present invention, the transmission apparatus changes the information modulation scheme and changes the frequency diversity order according to the transmission path state.

The multicarrier transmission method of the present invention is a multicarrier transmission method for transmitting user information from a transmission device to a reception device using a plurality of subcarriers having different frequencies.
Notifying a transmission path state from the receiving device to the transmitting device;
In the transmission device, determining a frequency diversity order according to the transmission path state;
Dividing the user information into at least one first signal and assigning to each of the first signals the frequency diversity order subcarriers constituting frequency diversity;
Modulating each of the first signals with subcarriers assigned to each of the first signals and then combining the modulated signals and sending them to the receiver as a multi-carrier modulated signal;
Receiving the multi-carrier modulation signal in the receiving apparatus, demodulating each of the subcarriers used in the transmitting apparatus to generate a plurality of second signals;
Receiving at least one third signal by performing diversity reception using the second signals of the frequency diversity order constituting frequency diversity; and
Combining at least one third signal to regenerate the user information.

Another multi-carrier transmission method of the present invention is a multi-carrier transmission method for transmitting user information from a transmission device to a reception device using a plurality of subcarriers having different frequencies.
Notifying a transmission path state from the receiving device to the transmitting device;
In the transmission device, selecting an information modulation method according to the transmission path state;
Determining a frequency diversity order according to the information modulation scheme and the transmission path state;
Modulating the user information with the information modulation scheme to generate a first signal;
Dividing the first signal into at least one second signal and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the second signals;
Combining each of the second signals after modulation with subcarriers assigned to each of the second signals and sending the resulting signal as a multi-carrier modulation signal to the receiving device;
Receiving the multi-carrier modulation signal in the receiving apparatus, demodulating each of the subcarriers used in the transmitting apparatus to generate a plurality of third signals;
Receiving at least one fourth signal by performing diversity reception using the third signals of the frequency diversity order constituting frequency diversity; and
Combining at least one of the fourth signals to generate a fifth signal;
Demodulating the fifth signal with the information modulation method to regenerate the user information.

The multicarrier transmission apparatus of the present invention is a multicarrier transmission apparatus that transmits user information to a receiving apparatus using a plurality of subcarriers having different frequencies from each other,
Subcarrier allocation control means for determining a frequency diversity order according to a transmission path state notified from the receiving device;
Subcarrier allocating means for dividing the user information into at least one signal, and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the signals;
Multi-carrier modulation means that modulates each of the signals with subcarriers assigned to each of the signals and then combines the modulated signals and sends them to the receiving apparatus as a multi-carrier modulation signal.

Another multicarrier transmission apparatus of the present invention is a multicarrier transmission apparatus that transmits user information to a receiving apparatus using a plurality of subcarriers having different frequencies.
Information modulation scheme control means for selecting an information modulation scheme in accordance with the transmission path state notified from the receiving device;
Subcarrier allocation control means for determining a frequency diversity order according to the information modulation scheme and the transmission path state;
Information modulating means for modulating the user information by the information modulation method and generating a first signal;
Subcarrier allocating means for dividing the first signal into at least one second signal, and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the second signals;
Multi-carrier modulation means that modulates each of the second signals with subcarriers assigned to each of the second signals, combines them, and sends them to the receiver as a multi-carrier modulation signal.

  According to the present invention, the transmitting device changes the frequency diversity order according to the transmission path state and transmits the user information after multi-carrier modulation, the receiving device performs multi-carrier inverse modulation, and synthesizes each signal of frequency diversity. Therefore, if the transmission path state is good, the communication speed is increased, and if the transmission path state is bad due to the influence of frequency selective fading, the degradation of communication quality can be reduced by frequency diversity.

  In addition, the transmission device changes the information modulation method and changes the frequency diversity order according to the transmission line condition, so the communication speed is increased if the transmission line condition is good, and the communication quality is deteriorated even if the transmission line condition is bad. Can be reduced.

  An embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a multicarrier transmission system according to an embodiment of the present invention. Referring to FIG. 1, the multicarrier transmission system includes a transmission device 11 and a reception device 12.

  The transmission apparatus 11 includes a signal input unit 13, an information modulation unit 14, a subcarrier allocation unit 15, a multicarrier modulation unit 16, and a subcarrier allocation control unit 17.

  The receiving device 12 includes a multicarrier demodulator 18, a subcarrier synthesizer 19, an information demodulator 20, and a signal output unit 21.

  In the transmission device 11, the signal input unit 13 provides user information to be transmitted to the information modulation unit 14 as a user information signal.

  The information modulation unit 14 modulates information on the user information signal given from the signal input unit 13 using a predetermined information modulation method (digital modulation method), and gives symbol data obtained thereby to the subcarrier allocation unit 15. . Examples of the information modulation method include QPSK and QAM.

  The subcarrier allocation unit 15 allocates subcarriers to each of the signals obtained by dividing the symbol data and converting it into at least one parallel signal in accordance with an instruction from the subcarrier allocation control unit 17. Then, the subcarrier allocation unit 15 gives each signal and information on the subcarrier allocated thereto to the multicarrier modulation unit 16. At that time, one subcarrier may be assigned to each of the signals converted into parallel, or a plurality of subcarriers may be assigned. The subcarrier information is, for example, a subcarrier number for identifying each subcarrier.

  In addition, the subcarrier allocation unit 15 notifies the reception apparatus 12 in advance of subcarrier information allocated to each signal and correspondence information indicating which subcarriers are allocated to the same signal.

  The multicarrier modulation unit 16 modulates (analog modulates) the signals from the subcarrier allocation unit 15 with the subcarriers assigned to the signal, synthesizes them, and transmits the multicarrier modulation signal from the antenna. As an example, the subcarriers are selected to be orthogonal to each other, and orthogonal modulation is performed.

  The subcarrier allocation control unit 17 stores the correspondence between the transmission path state information and the number of subcarriers in a table in advance. Then, the subcarrier allocation control unit 17 refers to the table based on the transmission path state information fed back from the receiving device 12, determines the number of subcarriers to be allocated to one signal, and further subcarrier numbers to be allocated to each signal Is notified to the subcarrier allocation unit 15. The transmission path state information is information indicating the state of the transmission path, and for example, SIR (signal to interference power ratio) is used. The number of subcarriers assigned to one signal is the frequency diversity order.

  In the receiving device 12, the multicarrier demodulation unit 18 receives a radio signal from the transmission device 11, demodulates and demodulates the same subcarriers used in the multicarrier modulation unit 16 of the transmission device 11. Each signal is given to the subcarrier combining unit 19.

  The subcarrier combining unit 19 combines (diversity combining) the same signals, to which a plurality of subcarriers are allocated, for each signal from the multicarrier demodulating unit 18 based on the information notified from the subcarrier allocation unit 15. Furthermore, symbol data obtained by converting all signals into serial signals and combining them is supplied to the information demodulator 20. At this time, the subcarrier combining unit 19 compensates and combines transmission path distortion for each subcarrier according to transmission path estimation, for example.

  The information demodulating unit 20 demodulates the symbol data from the subcarrier combining unit 19 using the same information modulation method as that used in the information modulating unit 14 of the transmission apparatus 11 and provides the demodulated data to the signal output unit 21.

  The signal output unit 21 outputs a signal from the information demodulation unit 20 as a user information signal. The signal output unit 21 measures a transmission path state (SIR) based on a predetermined control signal transmitted from the transmission apparatus 11 such as a pilot signal, and feeds back to the transmission apparatus 11 as transmission path state information. .

FIG. 2 is a flowchart showing the operation of the transmission device 11, and FIG. 3 is a flowchart showing the operation of the reception device 12. FIG. 4 is an example of a correspondence table of transmission path conditions (SIR), the number of subcarriers, and subcarrier arrangement patterns. In FIG. 4, SIR ₁ , SIR ₂ , SIR ₃ , SIR ₄ are SIR values, and their mutual relationship is SIR ₁ > SIR ₂ > SIR ₃ > SIR ₄ . n is a subcarrier number. 5 and 6 are diagrams showing examples of subcarrier allocation.

  Referring to FIG. 2, in transmitting apparatus 11, first, subcarrier allocation control unit 17 acquires a transmission path state (SIR) from receiving apparatus 12 (step 101). Then, the subcarrier allocation control unit 17 determines the number of subcarriers to be allocated to the same signal and the subcarrier arrangement pattern with reference to the correspondence table of FIG. 4, and further determines the subcarrier number (n in FIG. 4) ( Step 102).

  When user information is input to the signal input unit 13 (step 103), the information modulation unit 14 modulates the user information (step 104).

  Next, the subcarrier allocation unit 15 converts the symbol data, in which the user information is information-modulated, into parallel signals, and allocates subcarriers to each signal (step 105).

For example, if the acquired SIR values are SIR ₂ to SIR ₃ , the number of subcarriers is “2” from FIG. Therefore, the symbol data a1, a2, a3, a4... From the information modulation unit 14 are transmitted to the signals a1, a3, a5. are converted to a4, a6... Further, two subcarriers f1, f3 are assigned to the signals a1, a3, a5..., And two subcarriers f2, f4 are assigned to the signals a2, a4, a6.

  If the subcarrier number of subcarrier f1 is n1, the subcarrier number of subcarrier f3 is (n1 + N / 2). If the subcarrier number of subcarrier f2 is n2, the subcarrier number of subcarrier f4 is (n2 + N / 2). Here, N is the total number of subcarriers.

As another example, if the acquired SIR values are SIR ₁ to SIR ₂ , the number of subcarriers is “1” from FIG. 4. Therefore, the symbol data a1, a2, a3, a4... From the information modulation unit 14 are converted into signals a1, a5, a9..., Signals a2, a6 in the subcarrier allocation unit 15 as shown in FIG. , A10..., Signals a3, a7, a11... And signals a4, a8, a12. In addition, the signals a1, a5, a9... Have a subcarrier f1, the signals a2, a6, a10... Have a subcarrier f2, the signals a3, a7, a11. One subcarrier f4 is assigned to each of the signals a4, a8, a12.

  Returning to the description of FIG. 2, the multicarrier modulation unit 16 then modulates and synthesizes each signal with the frequency of the subcarrier assigned to each signal (step 106), and transmits it as a radio signal from the antenna. (Step 107).

  Referring to FIG. 3, in receiving apparatus 12, multicarrier demodulation section 18 receives a radio signal from transmitting apparatus 11 (step 201), demodulates it by orthogonal inverse transform, and separates it into subcarriers (step 202).

  Next, the subcarrier combining unit 19 combines the same signals to which a plurality of subcarriers are allocated by the subcarrier allocation unit 15 of the transmission apparatus 11 (step 203). At this time, the subcarrier combining unit 19 compensates and combines transmission path distortion for each subcarrier according to transmission path estimation, for example.

  Next, the information demodulating unit 20 demodulates with the information modulation method used in the information modulating unit 14 of the transmitting apparatus 11 (step 204), and the signal output unit 21 outputs it as user information (step 205).

  As described above, according to the multicarrier transmission system of the present embodiment, the subcarrier allocation unit 15 of the transmission device 11 changes the frequency diversity order according to the transmission path state, and the multicarrier modulation unit 16 converts the multicarrier. Since the multicarrier demodulating unit 18 of the receiving device 12 performs orthogonal inverse transform on the multicarrier and the subcarrier combining unit 19 combines the frequency diversity signals, the transmission speed is increased if the transmission path state is good. If the transmission path state is poor due to the influence of frequency selective fading, the degradation of communication quality can be reduced by frequency diversity.

  In the present embodiment, multicarrier transmission using four subcarriers is shown as an example, but the present invention is not limited thereto, and the number of subcarriers is not limited.

  Moreover, in this embodiment, SIR was shown as a parameter which shows a transmission-line state as an example, However, This invention is not limited to it, You may use another parameter.

  Moreover, in this embodiment, although the example which allocates 1-3 subcarriers to one signal was shown as an example (refer FIG. 4), this invention is not limited to it, It restrict | limits to the number of subcarriers allocated to one signal. There is no. The table in FIG. 4 is an example, and the present invention is not limited to this. For example, the subcarrier frequency band in the present invention is not limited.

  In the present embodiment, as an example, the subcarrier combining unit 19 compensates the transmission path distortion of each subcarrier based on the transmission path estimation. However, the present invention is not limited thereto, and other compensation methods are used. It may be used.

  Moreover, although the example which synthesize | combines each signal was shown in the subcarrier synthetic | combination part 19 of this embodiment as an example of diversity reception, this invention is not limited to it, Even if it uses diversity reception which selects one signal. Good.

  Another embodiment of the present invention will be described with reference to the drawings.

  FIG. 7 is a block diagram showing a configuration of a multicarrier transmission system according to another embodiment of the present invention.

  Referring to FIG. 7, the multicarrier transmission system includes a transmission device 31 and a reception device 32. The transmission device 31 includes a signal input unit 13, an information modulation unit 14, a subcarrier allocation unit 15, a multicarrier modulation unit 16, a subcarrier allocation control unit 17, and an information modulation scheme control unit 33. The receiving device 32 includes a multicarrier demodulator 18, a subcarrier synthesizer 19, an information demodulator 20, and a signal output unit 21.

  The multicarrier transmission system of FIG. 7 differs from FIG. 1 in that the transmission device 31 includes an information modulation scheme control unit 33.

  The information modulation scheme control unit 33 refers to the transmission path state information (SIR) fed back from the receiving device 32, selects the information modulation scheme used by the information modulation unit 14, and the information modulation unit 14 and subcarrier allocation control unit 17 is notified. For example, if the transmission line condition is good, an information modulation method with good communication efficiency that requires a good transmission line condition can be selected, but if the transmission line condition is bad, the communication quality deteriorates even if the transmission line condition is bad. It is preferable to select a few information modulation schemes.

  The information modulation unit 14 modulates the user information signal from the signal input unit 13 using the information modulation method notified from the information modulation method control unit 33.

  The subcarrier allocation control unit 17 stores the correspondence between the information modulation scheme and transmission path state information and the number of subcarriers in a table in advance. Then, the subcarrier allocation control unit 17 refers to the table using the information modulation scheme and transmission path state information notified from the information modulation scheme control unit 33, and determines the number of subcarriers allocated to one signal.

  FIG. 8 is a flowchart showing the operation of the transmission device 31 according to another embodiment. FIG. 9 is an example of a correspondence table of information modulation schemes and transmission path conditions (SIR), the number of subcarriers and subcarrier arrangement patterns.

  Referring to FIG. 8, in the transmission apparatus 31, first, the information modulation scheme control unit 33 acquires a transmission path state (SIR) from the reception apparatus 32 (step 301). Then, the information modulation scheme control unit 33 selects an information modulation scheme to be used by the information modulation unit 14 and notifies the information modulation unit 14 and the subcarrier allocation unit 17 (step 302).

  Next, the subcarrier allocation unit 17 determines the number of subcarriers to be allocated to the same signal and the subcarrier arrangement pattern with reference to the correspondence table of FIG. 9, and further determines the subcarrier number (n in FIG. 9) ( Step 303).

  When user information is input to the signal input unit 13 (step 304), the information modulation unit 14 modulates the user information with the information modulation method notified from the information modulation method control unit 33 (step 305).

  Next, the subcarrier allocation unit 15 converts the symbol data, in which the user information is information-modulated, into parallel signals. The number of subcarriers notified from the subcarrier allocation control unit 17 for each signal, the subcarrier arrangement pattern Accordingly, subcarriers are allocated to each signal (step 306).

  Next, the multicarrier modulation unit 16 modulates and synthesizes each of the signals with the frequency of the subcarrier assigned to each signal (step 307), and transmits the result as a radio signal from the antenna (step 308).

  The operation of the receiving device 32 is the same as that of the receiving device 12 shown in FIG.

  As described above, according to the multicarrier transmission system of the present embodiment, the information modulation unit 14 of the transmission device 31 changes the information modulation scheme according to the transmission path state, and the subcarrier allocation unit 15 uses the frequency diversity order. By changing, it is possible to increase the communication speed if the transmission line state is good, and to reduce the deterioration of communication quality even if the transmission line state is bad.

It is a block diagram which shows the structure of the multicarrier transmission system by one Embodiment of this invention. It is a flowchart which shows operation | movement of the transmitter by one Embodiment of this invention. It is a flowchart which shows operation | movement of the receiver by one Embodiment of this invention. It is an example of the correspondence table | surface of a transmission-line state (SIR), the number of subcarriers, and a subcarrier arrangement | sequence pattern. FIG. 5 is a diagram showing an example of sub-carrier allocation. FIG. 6 is a diagram showing another example of subcarrier allocation. It is a block diagram which shows the structure of the multicarrier transmission system by other embodiment of this invention. 6 is a flowchart illustrating an operation of a transmission apparatus according to another embodiment of the present invention. It is an example of the correspondence table | surface with an information modulation system and a transmission-line state (SIR), the number of subcarriers, and a subcarrier arrangement | sequence pattern. It is a block diagram which shows the structure of the conventional multicarrier transmission system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 31 Transmitter 12, 32 Receiver 13 Signal input part 14 Information modulation part 15 Subcarrier allocation part 16 Multicarrier modulation part 17 Subcarrier allocation control part 18 Multicarrier demodulation part 19 Subcarrier synthesis part 20 Information demodulation part 21 Signal Output unit 33 Information modulation system control unit 101-107, 201-205, 301-308 steps

Claims (6)

A multicarrier transmission method for transmitting user information from a transmission device to a reception device using a plurality of subcarriers having different frequencies from each other,
Notifying a transmission path state from the receiving device to the transmitting device;
In the transmission device, determining a frequency diversity order according to the transmission path state;
Dividing the user information into at least one first signal and assigning to each of the first signals the frequency diversity order subcarriers constituting frequency diversity;
Modulating each of the first signals with subcarriers assigned to each of the first signals and then combining the modulated signals and sending them to the receiver as a multi-carrier modulated signal;
Receiving the multi-carrier modulation signal in the receiving apparatus, demodulating each of the subcarriers used in the transmitting apparatus to generate a plurality of second signals;
Receiving at least one third signal by performing diversity reception using the second signals of the frequency diversity order constituting frequency diversity; and
Combining the at least one third signal to regenerate the user information. A multicarrier transmission method for transmitting user information from a transmission device to a reception device using a plurality of subcarriers having different frequencies from each other,
Notifying a transmission path state from the receiving device to the transmitting device;
In the transmission device, selecting an information modulation method according to the transmission path state;
Determining a frequency diversity order according to the information modulation scheme and the transmission path state;
Modulating the user information with the information modulation scheme to generate a first signal;
Dividing the first signal into at least one second signal and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the second signals;
Combining each of the second signals after modulation with subcarriers assigned to each of the second signals and sending the resulting signal as a multi-carrier modulation signal to the receiving device;
Receiving the multi-carrier modulation signal in the receiving apparatus, demodulating each of the subcarriers used in the transmitting apparatus to generate a plurality of third signals;
Receiving at least one fourth signal by performing diversity reception using the third signals of the frequency diversity order number constituting frequency diversity; and
Combining at least one of the fourth signals to generate a fifth signal;
Demodulating the fifth signal with the information modulation method to regenerate the user information. A multicarrier transmission apparatus that transmits user information to a reception apparatus using a plurality of subcarriers having different frequencies from each other,
Subcarrier allocation control means for determining a frequency diversity order according to a transmission path state notified from the receiving device;
Subcarrier allocating means for dividing the user information into at least one signal, and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the signals;
A multicarrier transmission apparatus comprising: a multicarrier modulation unit that modulates each of the signals with subcarriers assigned to each of the signals and then combines the modulated signals and sends the combined signals to the reception apparatus as a multicarrier modulation signal. A multicarrier transmission apparatus that transmits user information to a reception apparatus using a plurality of subcarriers having different frequencies from each other,
Information modulation scheme control means for selecting an information modulation scheme in accordance with the transmission path state notified from the receiving device;
Subcarrier allocation control means for determining a frequency diversity order according to the information modulation scheme and the transmission path state;
Information modulating means for modulating the user information by the information modulation method and generating a first signal;
Subcarrier allocating means for dividing the first signal into at least one second signal, and allocating the frequency diversity order subcarriers constituting frequency diversity to each of the second signals;
A multicarrier transmission apparatus comprising: a multicarrier modulation unit that modulates each of the second signals with subcarriers assigned to each of the second signals, and then combines the modulated signals and transmits the resultant signals as multicarrier modulation signals to the reception apparatus. A multicarrier transmission system for transmitting user information using a plurality of subcarriers having different frequencies from each other,
The user information is divided into at least one signal, and frequency-diversity order subcarriers corresponding to the transmission path state are allocated to each of the divided signals and modulated by the subcarriers, and the obtained signals are combined. And transmitting as a multi-carrier modulation signal,
The multicarrier modulation signal from the transmission device is demodulated by the same subcarrier as that used in the transmission device, and diversity reception is performed using a signal constituting frequency diversity among signals obtained by demodulation, and diversity reception is performed. A multi-carrier transmission system comprising: a receiving device that obtains the user signal by combining at least one signal obtained by the above. The transmitting apparatus modulates the user information with an information modulation scheme selected according to the transmission path state, and then divides the user information into at least one signal, and frequency diversity orders according to the transmission path state and the information modulation scheme Each of the signals is modulated with subcarriers and combined into the multi-carrier modulation signal;
The reception apparatus demodulates the multicarrier modulation signal with the subcarrier, receives diversity reception using the signals constituting frequency diversity, combines signals obtained by diversity reception, and then is used in the transmission apparatus The multicarrier transmission system according to claim 5, wherein the user signal is obtained by demodulating information using the same information modulation method as described above.

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