Wireless communication system, wireless communication method, and wireless communication transmitter

Abstract

This disclosure is related to a radio communication system using a quadrature amplitude modulation scheme, and the purpose of this disclosure is to effectively prevent misidentification of data while utilizing a non-linear region of an amplifier. According to this disclosure, a transmission device includes a transmission signal amplifier for variable transmission power, a transmission power control unit that controls the transmission power, and an approximate pattern information reporting unit that generates pattern information of an approximate constellation. When 64 QAM is used as a modulation scheme, a 64-QAM distortion constellation is generated in a non-linear region of the transmission signal amplifier. In this case, a 64-APSK approximate constellation is generated, and the pattern information of the 64-APSK approximate constellation is transmitted to a reception device. The reception device performs a likelihood calculation for reception points indicated by a data signal by using an approximate constellation corresponding to the pattern information.

Description

[Technical field]

[0001] The present disclosure relates to a wireless communication system, a wireless communication method, and a wireless communication transmitting device, and more particularly to a wireless communication system, a wireless communication method, and a wireless communication transmitting device that use a quadrature amplitude modulation scheme. [Background technology]

[0002] Non-Patent Document 1 below discloses a technique related to a wireless communication system using a quadrature amplitude modulation (QAM) method. In wireless communication, the higher the transmission power, the higher the SNR (Signal to Noise Ratio) can be.

[0003] On the other hand, amplifiers for transmission signals generally exhibit linear input / output characteristics when the input power is low, but exhibit nonlinear characteristics when the input power is high. For this reason, in wireless communications, the higher the transmission power, the more likely distortion will occur in the transmission signal.

[0004] In a wireless communication system using the QAM method, a transmission signal emitted from a transmitting device forms a constellation that is regularly arranged in a grid if it is not accompanied by distortion, and a receiving device identifies a received signal as one that forms such a regular constellation.

[0005] Under these conditions, if distortion occurs in the transmission signal, the correspondence between the actually transmitted signal and the constellation assumed by the receiving device will be lost, which may result in the receiving device being unable to correctly identify the data.

[0006] The above-mentioned Non-Patent Document 1 discloses a technique for keeping the transmission power within the linear region of the amplifier in order to avoid the influence of such distortion. If the transmission signal is within the linear region of the amplifier, distortion will not be superimposed on the transmission signal. Therefore, according to the technique described in the above-mentioned Non-Patent Document 1, it is possible to always have the receiving device process the signal correctly, and it is possible to effectively prevent misrecognition of data. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] High-Speed ​​Satellite Mobile Communications: Technologies and Challenges, MOHAMED IBNKAHLA, QUAZI MEHBUBAR RAHMAN, AHMED IYANDA SULYMAN, HISHAM ABDULHUSSEIN AL-ASADY, JUN YUAN, AND AHMED SAFWAT, p312-339, PROCEEDINGS OF THE IEEE, VOL. 92, NO. 2, February 2004 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the technology of Non-Patent Document 1 solves the distortion problem by abandoning the use of the non-linear region of the amplifier. In other words, this technology does not allow the amplifier to fully demonstrate its inherent capabilities, which goes against the essential requirement of using large power without excessive capital investment.

[0009] The present disclosure has been made in consideration of the above-mentioned problems, and has a first objective to provide a wireless communication system that can effectively prevent misidentification of data while utilizing the nonlinear region of an amplifier in wireless communication using QAM.

[0010] A second object of the present disclosure is to provide a wireless communication method for effectively preventing misidentification of data while utilizing the nonlinear region of an amplifier in wireless communication using QAM.

[0011] A third object of the present disclosure is to provide a wireless communication transmitting device capable of effectively preventing erroneous recognition of data while utilizing the nonlinear region of an amplifier in wireless communication using QAM. [Means for solving the problem]

[0012] In order to achieve the above object, a first aspect is a wireless communication system including a transmitting device and a receiving device that perform wireless communication using a quadrature amplitude modulation scheme, The transmitting device a transmission signal amplifier having a variable transmission power; a transmission power control unit that controls a transmission power used by the transmission signal amplifier; an approximate pattern information notifying unit that generates pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles based on the transmission power; an information bit generator that generates information bits so that the pattern information is transmitted prior to a data signal; It is preferable that the receiving device includes a likelihood calculation unit that performs likelihood calculation for a reception point indicated by the data signal using an approximate constellation corresponding to the pattern information.

[0013] A second aspect is a wireless communication method using a transmitting device and a receiving device that perform wireless communication using a quadrature amplitude modulation scheme, the transmitting device includes a transmission signal amplifier having a variable transmission power; controlling a transmission power used by the transmission signal amplifier; an approximate pattern information notification step of generating, based on the transmission power, pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles; transmitting said pattern information to said receiving device prior to a data signal; a likelihood calculation step in which the receiving device performs likelihood calculation for a reception point indicated by the data signal by using an approximate constellation corresponding to the pattern information; It is preferable that the present invention includes the following:

[0014] A third aspect is a wireless communication transmitting device that performs wireless communication with a receiving device using a quadrature amplitude modulation scheme, a transmission signal amplifier having a variable transmission power; a transmission power control unit that controls a transmission power used by the transmission signal amplifier; an approximate pattern information notifying unit that generates pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles based on the transmission power; an information bit generator that generates information bits so that the pattern information is transmitted prior to a data signal; It is desirable to have the following: Effect of the Invention

[0015] According to the first to third aspects, it is possible to effectively prevent data from being erroneously recognized in the receiving device while utilizing the nonlinear region of the amplifier included in the transmitting device. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram for explaining an overall configuration of a wireless communication system according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram for explaining the configuration of a transmission device to be compared with the transmission device according to the first embodiment of the present disclosure. [Diagram 3] 1 is a diagram showing input / output characteristics of an amplifier built into a transmitting device. [Figure 4] FIG. 13 is a diagram showing how distortion occurs in a constellation as the transmission power increases. [Diagram 5] FIG. 2 is a block diagram illustrating a configuration of a transmission device according to a first embodiment of the present disclosure. [Figure 6] FIG. 1 is a diagram showing a comparison between a distorted constellation and an approximated constellation. [Figure 7] FIG. 2 is a block diagram for illustrating a configuration of a receiving device according to a first embodiment of the present disclosure. [Figure 8] 11 is a flowchart illustrating a flow of processing executed by an approximate pattern information notification unit of the transmission device according to the first embodiment of the present disclosure. [Figure 9] 4 is a flowchart for explaining a flow of processing executed by a likelihood calculation unit of a receiving device in the first embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Embodiment 1 [Overall configuration of the first embodiment] Fig. 1 shows an overall configuration of a wireless communication system according to a first embodiment of the present disclosure. As shown in Fig. 1, the wireless communication system according to the present embodiment includes a transmitting device 10 and a receiving device 12. The transmitting device 10 is configured, for example, as a mobile communication base station operated by a telecommunications carrier or a WiFi (registered trademark) access point. The receiving device 12 is configured as a terminal station such as a smartphone or a tablet terminal.

[0018] [Issues Focused on in the First Embodiment] 2 is a block diagram for explaining the configuration of a transmitting device 14 for comparison with the transmitting device 10 in this embodiment. The transmitting device 14 of the comparative example includes an information bit generating unit 16. The information bit generating unit 16 generates information bits to be transmitted to the receiving device 12. The information bit generating unit 16 may include an error correction coding function or an interleaving function.

[0019] The information bits generated by the information bit generation unit 16 are provided to a data signal modulation unit 18. The data signal modulation unit 18 modulates the provided information bits into a data signal. Quadrature amplitude modulation (QAM) is used as the modulation method.

[0020] The data signal generated by the data signal modulation unit 18 is provided to a digital-to-analog conversion unit 20. The digital-to-analog conversion unit 20 converts the digitally modulated data signal into an analog transmission signal.

[0021] The transmission signal generated in the digital-to-analog conversion unit 20 is provided to a transmission signal amplifier 22. The transmission signal amplifier 22 amplifies the transmission signal and provides it to an antenna 24. The transmission signal is then transmitted from the antenna 24 to the receiving device 12 in the form of a radio signal.

[0022] 3 shows the input / output characteristics of the transmission signal amplifier 22. As shown in FIG. 3, the output power (vertical axis) of the transmission signal amplifier 22 is proportional to the input power (horizontal axis) P B In the smaller region, it is proportional to the input power. And, when the input power is P B In the following, the region where the two are proportional to each other is referred to as the "linear region," and the region where the proportional relationship between the two is lost is referred to as the "nonlinear region."

[0023] Figure 4 shows how distortion occurs in an 8x8=64QAM constellation as the transmission power increases. In the 64QAM modulation method, 64 symbols arranged in a grid pattern are defined by changing and adjusting the amplitude of two independent carrier waves. Hereinafter, the points on the constellation coordinates where each of the 64 symbols is defined are referred to as "signal points." Also, the points on the constellation coordinates of each data signal that is actually transmitted are referred to as "reception points."

[0024] In the linear region of the transmission signal amplifier 22, the reception points form a constellation without distortion, as shown on the left side of FIG. 4 (transmission power P1). On the other hand, in the nonlinear region of the transmission signal amplifier 22, the reception points form a constellation without distortion, as shown on the right side of FIG. 4 (transmission power P N As shown in FIG. 1, distortion is superimposed on the constellation at the reception point. Hereinafter, a constellation without distortion is called a "normal constellation." A constellation with distortion is called a "distorted constellation."

[0025] The receiver 12 calculates the likelihood of each reception point included in the transmission signal with respect to nearby signal points, and recognizes each reception point as one of 64 symbols based on the result. The likelihood calculation can be performed, for example, by a method described in the following document.

[0026] On the Optimality of Bit Detection of Certain Digital Modulations, Marvin K. Simon and Ramesh Annavajjala, p299-307, IEEE TRANSACTIONS ON COMMUNICATIONS, VOL. 53, NO. 2, FEBRUARY 2005

[0027] When the receiving device 12 performs likelihood calculation using the signal points of the normal constellation, the receiving points generated in the linear domain are correctly recognized. However, the receiving points generated in the nonlinear domain are shifted from the normal positions. Therefore, the receiving device 12 that calculates the likelihood using the normal constellation cannot correctly calculate the likelihood for the receiving points generated in the nonlinear domain. As a result, the receiving device 12 may misrecognize the data.

[0028] In the comparative example of transmitting device 14, if the transmission power is limited to the linear region of transmitting signal amplifier 22, it is possible to prevent distortion from being superimposed on the receiving point. Therefore, if such a limit is imposed, it is possible to prevent erroneous recognition of data in receiving device 12. However, in this case, the amplification capability of transmitting signal amplifier 22 cannot be fully utilized.

[0029] The input / output characteristics as shown in Fig. 3 can be known in advance in the transmitting device 14. If the input / output characteristics are known in advance, the distortion superimposed on the constellation can be estimated as a function of the transmission power. Therefore, in the transmitting device 14, at the stage where the transmission power to be used in communication is determined, it is possible to estimate the distortion constellation corresponding to that transmission power.

[0030] When the nonlinear region of the transmission signal amplifier 22 is used, if the transmission device 14 provides the reception device 12 with information on the estimated distortion constellation, the reception device 12 can use the distortion constellation to perform a correct likelihood calculation for the reception point. Also, such processing makes it possible to fully utilize the amplification capability of the transmission signal amplifier 22.

[0031] However, providing information on distorted constellations entails a large amount of communication traffic. For example, in the case of 64QAM, it is necessary to transmit the amplitude and phase for 64 signal points. In addition, since the amount of distortion of the constellation changes depending on the transmission power, the information needs to be provided every time the transmission power changes. For this reason, if an attempt is made to utilize the nonlinear region by providing information on distorted constellations to the receiving device 12, the data rate in communication will be significantly reduced.

[0032] In order to suppress such a decrease in data rate, the wireless communication system of this embodiment replaces the distorted constellation with an approximate constellation having less information and provides it to the receiving device 12. A method in which the system of this embodiment uses the approximate constellation will be described in detail below.

[0033] [Features of the first embodiment]

[0034] Fig. 5 is a block diagram of the transmitting device 10 of this embodiment. In Fig. 5, the same elements as those included in the transmitting device 14 of the comparative example (see Fig. 2) are denoted by the same reference numerals, and the description thereof will be omitted or simplified.

[0035] The transmitting device 10 includes a transmission power control unit 26 in front of the transmission signal amplifier 22. The transmission power control unit 26 controls the transmission power used by the transmission signal amplifier 22 so as to obtain a desired communication quality. A control command from the transmission power control unit 26 is provided to the transmission signal amplifier 22 and also to an approximate pattern information notification unit 28.

[0036] When the transmission power falls within the linear region of the transmission signal amplifier 22, the approximate pattern information notifying unit 28 provides that fact to the information bit generating unit 30. When the transmission power falls within the nonlinear region of the transmission signal amplifier 22, the approximate pattern information notifying unit 28 generates pattern information that indicates an approximate constellation of the distortion constellation that corresponds to that transmission power. This pattern information is provided to the information bit generating unit 30.

[0037] The information bit generator 30 has the same function as the information bit generator 16 included in the transmitting device 14 of the comparative example, and also has a function of converting information provided by the approximate pattern information notifier 28 into bits. That is, the information indicating that the transmission power belongs to a linear region and the pattern information of the approximate constellation are converted into bits. Hereinafter, these pieces of information are referred to as "constellation information".

[0038] The constellation information is transmitted prior to the data signal, so that the receiver 12 can receive information of the approximate constellation corresponding to the transmission power of the data signal before receiving the data signal.

[0039] Figure 6 shows a comparison of a 64QAM distorted constellation and its approximate constellation. In the 64QAM distorted constellation, the 64 signal points tend to become more dense the further away from the center they are. These signal points can be grouped as being on any of several concentric circles. More specifically, when the modulation method is 64QAM, the signal points of the distorted constellation can be approximated as being on any of four concentric circles, similar to the 64APSK (Amplitude Phase Shift Keying) constellation.

[0040] The approximate constellation shown on the right side of Figure 6 is obtained by grouping the 64 signal points as those that fall on one of the four concentric circles. In order to transmit all of the signal points included in the distorted constellation, it is necessary to define the radius and phase, or the X and Y coordinates, for all of the 64 signal points. In contrast, with the approximate constellation, radius information can be shared between multiple signal points that fall on the same concentric circle. Therefore, the amount of information representing the approximate constellation is smaller than the amount of information representing the distorted constellation.

[0041] In this embodiment, when a transmission power belonging to a nonlinear region is used, the approximate pattern information notification unit 28 first generates a distorted constellation as shown in the left side of Fig. 6 based on the transmission power. Next, the approximated constellation is generated by approximating the signal points included in the distorted constellation as belonging to one of four concentric circles. Then, the information of the approximated constellation is converted into bits by the information bit generation unit 30 and then transmitted to the receiving device 12.

[0042] 7 is a block diagram for explaining the configuration of the receiving device 12. The receiving device 12 includes an antenna 32 for transmitting and receiving wireless signals to and from the transmitting device 10. The signal received by the antenna 32 is provided to a receiving signal amplifier 34. The receiving signal amplifier 34 amplifies the received signal with an appropriate gain and provides the amplified signal to an analog-to-digital converter 36.

[0043] The analog-to-digital converter 36 is a block for demodulating the received analog signal into a digital signal. The signal digitized by the analog-to-digital converter 36 is provided to a data signal equalizer 38.

[0044] The data signal equalization unit 38 is a block that obtains an estimate of the received signal by inversely calculating the information on the amplitude and phase of the channel response. A training signal is exchanged between the transmitting device 10 and the receiving device 12 prior to the data signal. The contents of the training signal are shared in advance between the transmitting device 10 and the receiving device 12. Therefore, the receiving device 12 can detect the influence caused by the communication channel based on the training signal actually received. Specifically, the data signal equalization unit 38 reflects the result of the training in the data signal received by the receiving device 12, thereby generating a data signal in which the influence caused by the communication channel is offset. The data signal generated by the data signal equalization unit 38 is provided to the likelihood calculation unit 40.

[0045] The likelihood calculation unit 40 performs likelihood calculation for the reception point indicated by the data signal and some of the signal points on the constellation to be compared. Then, the signal point for which the highest likelihood is obtained is recognized as the symbol intended by the current reception point. When the transmission power belongs to a linear region, the likelihood calculation unit 40 uses a normal constellation as the constellation to be compared. When the transmission power belongs to a nonlinear region, an approximate constellation is used as the constellation to be compared. The signal symbolized by the likelihood calculation unit 40 is provided to an information bit detection unit 42.

[0046] The information bit detector 42 detects received bits from the symbolized signal. The information bit detector 42 may have an error correction decoding function and an interleaving function, if necessary.

[0047] [Characteristic processing of the transmitter] Fig. 8 is a flowchart for explaining the flow of processing executed by the approximate pattern information notification unit 28 of the transmitting device 10. As shown in Fig. 8, in this routine, first, the transmission power set in the transmission power control unit 26 is detected (step 100).

[0048] Next, it is determined whether the transmission power is within the linear region of the transmission signal amplifier 22 (step 102).

[0049] As a result, if it is determined that the signal belongs to the linear region, it can be determined that no distortion is superimposed on the transmission signal. In this case, the fact that the transmission signal belongs to the linear region is notified to the information bit generator 30 as constellation information in the linear region (step 104). Thereafter, this information is transmitted to the receiver 12 prior to the data signal.

[0050] On the other hand, if it is determined in step 102 that the transmission power does not belong to the linear region, an approximate constellation that imitates the APSK constellation is generated (step 106). Specifically, first, a distorted constellation corresponding to the transmission power is generated based on the specifications of the transmission signal amplifier 22. Next, the signal points included in the distorted constellation are approximated as being on any of a predetermined number of concentric circles.

[0051] Next, the signal points included in the approximate constellation are grouped into groups of those that fall on the same concentric circle. Next, the radius of the concentric circle of each group is set as information common to the signal points that belong to each group. Furthermore, the phase is set as information for each signal point (step 108).

[0052] After the above process is completed, the group information of the signal points, the radius information of each group, and the phase information of each signal point are provided to the information bit generator 30 as constellation information in the nonlinear domain (step 110). After that, this information is transmitted to the receiver 12 prior to the data signal.

[0053] [Characteristic processing of receiving device] Fig. 9 is a flowchart for explaining the flow of processing executed by the likelihood calculation unit 40 of the receiving device 12. As shown in Fig. 9, in this routine, first, constellation information is detected from the received signal (step 120).

[0054] Next, it is determined whether the detected constellation information is information in a linear region (step 122).

[0055] As a result, if it is determined that the constellation information is information in a linear region, it can be determined that no distortion is superimposed on the received signal. In this case, the normal constellation is set as the constellation to be compared with the received point when calculating the likelihood (step 124).

[0056] Thereafter, the likelihood calculation for the reception point is performed using the set constellation (step 126). In a situation where no distortion is superimposed on the reception point, the likelihood can be calculated correctly by using the normal constellation. Therefore, the receiving device 12 can correctly symbolize the reception point.

[0057] If the constellation information in the nonlinear region is received, the determination in the above step 122 is negative. In this case, an approximate constellation is generated based on the received constellation information. Then, the approximate constellation is set as the constellation to be used for the likelihood calculation (step 128).

[0058] In this case, in step 126, the likelihood calculation is performed based on the approximate constellation instead of the normal constellation. The approximate constellation reflects the distortion superimposed on the reception point. Therefore, even if the reception point is superimposed with distortion, the receiving device 12 can perform a correct likelihood calculation and can properly symbolize the reception point.

[0059] As described above, according to this embodiment, when the transmission power belongs to the linear region of the transmission signal amplifier 22, the receiving device 12 executes the likelihood calculation using a normal constellation. As a result, the data signal is transmitted correctly.

[0060] Furthermore, according to this embodiment, when the transmission power falls within the nonlinear region of the transmission signal amplifier 22, information on the approximate constellation can be provided to the receiving device 12. The approximate constellation reflects the influence of the distortion superimposed at the reception point. Therefore, even if the distortion is superimposed at the reception point, the data signal is transmitted correctly.

[0061] Furthermore, the amount of information required to share the approximate constellation is smaller than the amount of information required to share the distorted constellation. Therefore, the amount of information required to be provided to the receiving device 12 can be reduced compared to the case where the distorted constellation itself is provided to the receiving device 12. As a result, according to this embodiment, it is possible to achieve proper data transmission while maintaining a high data rate and utilizing the amplification capability of the transmission signal amplifier 22 without waste.

[0062] [Modification of the first embodiment] Incidentally, in the above-mentioned first embodiment, the case where the modulation method is 64QAM has been described, but the present disclosure is not limited to this. That is, the modulation method applicable to the present disclosure is not limited to 64QAM, and other modulation methods such as 256QAM can also be applied. [Explanation of symbols]

[0063] 10 Transmitting device 12 Receiving device 22 Transmitting signal amplifier 26 Transmission power control section 28 Approximate pattern information notification unit 30 Information bit generator 40 Likelihood calculation section

Claims

1. A wireless communication system including a transmitting device and a receiving device that perform wireless communication using a quadrature amplitude modulation scheme, The transmitting device a transmission signal amplifier having a variable transmission power; a transmission power control unit that controls a transmission power used by the transmission signal amplifier; an approximate pattern information notifying unit that generates pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles based on the transmission power; an information bit generator that generates information bits so that the pattern information is transmitted prior to a data signal; The receiving device is a wireless communication system including a likelihood calculation unit that performs likelihood calculation for a reception point indicated by the data signal using an approximate constellation corresponding to the pattern information.

2. The approximate pattern information notification unit generating pattern information of the approximate constellation when the transmission power belongs to a nonlinear region of the transmission signal amplifier; When the transmission power belongs to a linear region of the transmission signal amplifier, linear information is generated that represents a state in which the transmission power belongs to the linear region; the information bit generation unit is configured to generate information bits such that, when the linear information is generated instead of the pattern information, the linear information is transmitted prior to the data signal; The wireless communication system according to claim 1 , wherein the likelihood calculation unit is configured to execute the likelihood calculation using the normal constellation when the linear information is transmitted to the receiving device.

3. The pattern information of the approximate constellation is information representing the radius of each of the concentric circles; Information indicating on which of the concentric circles each of the signal points is located; and information representing a phase of each of the signal points on the approximate constellation; 3. A wireless communication system according to claim 1, comprising:

4. 4. The wireless communication system according to claim 1, wherein the quadrature amplitude modulation is nQAM in which n signal points are defined on a constellation, and the number of concentric circles included in the approximation constellation is the same as the number of concentric circles included in an nAPSK constellation corresponding to the n signal points.

5. A wireless communication method using a transmitting device and a receiving device that perform wireless communication using a quadrature amplitude modulation scheme, the transmitting device includes a transmission signal amplifier having a variable transmission power; controlling a transmission power used by the transmission signal amplifier; an approximate pattern information notification step of generating, based on the transmission power, pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles; transmitting said pattern information to said receiving device prior to a data signal; a likelihood calculation step in which the receiving device performs likelihood calculation for a reception point indicated by the data signal by using an approximate constellation corresponding to the pattern information; A wireless communication method comprising:

6. The approximate pattern information notification step includes: generating pattern information of the approximate constellation when the transmission power belongs to a nonlinear region of the transmission signal amplifier; generating linear information representing a state in which the transmission power belongs to a linear region of the transmission signal amplifier when the transmission power belongs to the linear region of the transmission signal amplifier; The wireless communication method according to claim 5 , wherein the likelihood calculation step further comprises the step of performing the likelihood calculation using the normal constellation when the linear information is transmitted to the receiving device.

7. A wireless communication transmitting device that performs wireless communication with a receiving device using a quadrature amplitude modulation method, a transmission signal amplifier having a variable transmission power; a transmission power control unit that controls a transmission power used by the transmission signal amplifier; an approximate pattern information notifying unit that generates pattern information of an approximate constellation obtained by approximately arranging each of the signal points included in a normal constellation of the quadrature amplitude modulation on any of a predetermined number of concentric circles based on the transmission power; an information bit generator that generates information bits so that the pattern information is transmitted prior to a data signal; A wireless communication transmitting device comprising:

8. The approximate pattern information notification unit generating pattern information of the approximate constellation when the transmission power belongs to a nonlinear region of the transmission signal amplifier; When the transmission power belongs to a linear region of the transmission signal amplifier, linear information is generated that represents a state in which the transmission power belongs to the linear region; 8. The wireless communication transmitting device according to claim 7, wherein the information bit generating unit is configured to generate information bits such that, when the linear information is generated instead of the pattern information, the linear information is transmitted prior to the data signal.

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