JP6495843B2 - Evaluation method, evaluation apparatus, and program for wireless communication system - Google Patents

Description

  The present invention relates to an evaluation method, an evaluation apparatus, and a program for a wireless communication system.

  It is useful to quantitatively evaluate the effects of fading due to multiple waves in wireless communication by computer simulation, because it is easier to perform than experimental evaluation in a real environment. In computer simulation, there is a method using a radio scatterer model as a model for simulating a multi-wave environment (Non-Patent Document 1). The radio wave scatterer model is mainly used for fading evaluation in a non-line-of-sight cellular environment, and there are a plurality of radio wave scatterers around a terminal moving at a velocity v in the direction of angle β, and the transmission signal is a radio wave scatterer. This is a model in which each reflected wave is synthesized at a terminal that is a reception point.

FIG. 6 is a diagram showing an outline of the radio wave scatterer model. The transmission signal s (t) transmitted from the transmitter is reflected by n radio wave scatterers existing around the terminal and reaches the terminal. The propagation phase of each of the reflected waves reflected by the N radio wave scatterers is η _n (n = 1, 2,..., N). When r (t) is a reception signal at the reception point where the reflected waves reflected by n radio wave scatterers are combined, the relationship between the transmission signal s (t) and the reception signal r (t) is an expression. It is represented by (1).

In Equation (1), f _d is a Doppler frequency and f _d = v / λ (λ is the wavelength of the carrier wave of the transmission signal). Β _n is an angle formed by the moving direction β of the terminal with the direction from the radio wave scatterer n to the terminal. Here, when the propagation phase η _n of the reflected wave by the radio wave scatterer around the terminal is uncorrelated and is determined randomly in the range of −2π <η _n ≦ 2π, the amplitude component | A (t) | Follows the Rayleigh distribution and the phase component θ follows the uniform distribution, and the relationship of Expression (2) is established.

  In general, in a multi-wave environment where there is no line of sight, it is said that the amplitude of the fading channel has a Rayleigh distribution and the phase has a uniform distribution. it can.

J. D. Parsons, "The Mobile Radio Propagation Channel, Second Edition", John Wiley & Sons, LTD, 2000

  However, the radio wave scatterer model in the above-described method is a model within the same polarization. Therefore, even if the above-mentioned radio wave scatterer model is applied to a computer simulation for evaluating channel characteristics and the like in a wireless communication system that performs transmission by combining different polarizations such as polarization MIMO (Multiple-Input Multiple-Output). Since the effect between waves was not taken into account, there was room for improvement in the evaluation results obtained.

  In view of the foregoing circumstances, an object of the present invention is to provide a wireless communication system evaluation method, evaluation device, and program capable of improving the accuracy of simulation for a wireless communication system that performs transmission by combining different polarizations. Yes.

  One aspect of the present invention is a method for evaluating a wireless communication system that performs transmission by combining different polarizations, and includes information on radio scatterers in a radio wave scatterer in an out-of-sight multiwave environment between a transmission point and a reception point. Radio wave scatterer information acquisition step, and a radio wave scatterer that indicates a polarization conversion amount indicating a distribution ratio of components between the different polarizations when a transmission signal transmitted from the transmission point is reflected on the radio wave scatterer. A polarization conversion amount calculating step for each radio wave scatterer based on the information; a polarization conversion amount calculated by the polarization conversion amount calculating step; and the radio wave scatterer information based on the polarization conversion amount and the radio wave scatterer information. A reception component calculation step of calculating reception components of different polarized waves for each reflected wave at the radio wave scatterer, and reflection at the radio wave scatterer by moving to the reception point. A Doppler fluctuation calculation step for calculating for each radio wave scatterer a phase rotation amount due to Doppler fluctuation received by the reflected wave, and a phase rotation amount calculated by the Doppler fluctuation calculation step for the reception component calculated by the reception component calculation step. Is added to each of the different polarizations, and then the wireless communication system evaluation method.

  Further, according to an aspect of the present invention, in the evaluation method of the wireless communication system, in the polarization conversion amount calculating step, an incident surface of the transmission signal with respect to a reflection surface in the radio wave scatterer included in the radio wave scatterer information The reflection coefficient between the TM wave component parallel to the incident surface and the TE wave component perpendicular to the incident surface is calculated on the basis of the oblique angle and the dielectric constant of the radio wave scatterer, and the TM wave component and the TE wave component are calculated. The TM wave component and the TE wave component of the reflected wave reflected by the radio wave scatterer are calculated using the reflection coefficient, and the calculated TM wave component and the TE wave component are synthesized. Calculate the amount of wave conversion.

  Further, according to an aspect of the present invention, in the evaluation method for the wireless communication system, the transmission may be performed based on the reception component and the transmission signal for each different polarization at the reception point calculated by the addition processing step. A channel characteristic calculating step of calculating a channel characteristic between the point and the reception point.

  Another embodiment of the present invention is an evaluation apparatus for a wireless communication system that performs transmission by combining different polarizations, and the radio wave scattering related to the radio wave scatterer in a multi-wave environment that is not visible between the transmission point and the reception point. A radio wave scatterer information acquisition unit for acquiring body information, and a polarization conversion amount indicating a distribution ratio of components between the different polarizations when a transmission signal transmitted from the transmission point is reflected on the radio wave scatterer. Based on the polarization conversion amount calculated by the polarization conversion amount calculation unit and the radio wave scatterer information, the polarization conversion amount calculation unit that calculates for each radio wave scatterer based on the scatterer information, and at the reception point A reception component calculation unit that calculates reception components of each of the different polarized waves for each reflected wave at the radio wave scatterer, and a signal received by the reflected wave reflected by the radio wave scatterer by moving to the reception point. The Doppler fluctuation calculation unit that calculates the phase rotation amount due to the puller fluctuation for each radio wave scatterer, and the phase rotation amount calculated by the Doppler fluctuation calculation unit is added to the reception component calculated by the reception component calculation unit, and then the different deviations are added. It is an evaluation apparatus provided with the addition process part added for every wave.

  One embodiment of the present invention is a program for causing a computer to execute the above-described evaluation method computer for a wireless communication system.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to improve the precision of the simulation with respect to the radio | wireless communications system which transmits by combining different polarized waves.

6 is a flowchart showing a method for evaluating a wireless communication system according to the present embodiment. The figure which shows the outline | summary of a radio wave reflection. The figure which shows an example in which an incident vector becomes diagonal with respect to a medium boundary surface. The figure which shows the outline | summary of the electromagnetic wave scatterer model of this embodiment. The block diagram which shows the structural example of the evaluation apparatus of the radio | wireless communications system in this embodiment. The figure which shows the outline | summary of a radio wave scatterer model.

Hereinafter, a wireless communication system evaluation method, evaluation device, and program according to embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flowchart showing a method for evaluating a wireless communication system according to the present embodiment. The evaluation method according to the present embodiment is characterized in that the amount of polarization conversion between different polarizations is determined based on the inclination angle of the transmission signal with respect to the incident surface of the plurality of radio wave scatterers, and the wireless communication system is evaluated. . In this evaluation method, the propagation phase η _n and the polarization generated by the reflection by the radio wave scatterer n for the signal s _v (t) transmitted by the vertically polarized wave and the signal s _h (t) transmitted by the horizontally polarized wave. A conversion amount P _nh is calculated. Note that n = 1, 2,..., N.

In the radio communication system evaluation method according to the present embodiment, there is a model in which a transmission signal transmitted from a transmitter is reflected by N radio wave scatterers and received by a terminal, such as the radio wave scatterer model shown in FIG. Used. In the present embodiment, the transmission signals are a vertically polarized signal s _v (t) and a horizontally polarized signal s _h (t). When the evaluation of the wireless communication system is started, the evaluation device acquires radio wave scatterer information (step S11) and acquires the propagation phase of each radio wave scatterer (step S12). Subsequently, the evaluation device calculates a polarization conversion amount P _nh for each radio wave scatterer based on the acquired radio wave scatterer information (step S13).

Based on the transmission signals s _v (t) and s _h (t) and the calculated polarization conversion amount P _nh , the evaluation device converts the reception components of the vertical polarization and the horizontal polarization at the reception point into a radio wave scattering object. It calculates for every (step S14). The evaluation apparatus calculates a phase rotation amount due to Doppler fluctuations with respect to the reception components of the vertical polarization and the horizontal polarization for each radio wave scattering object (step S15), and each of the vertical polarization and the horizontal polarization for each radio wave scatterer is calculated. The received components r _v (t) and r _h (t) obtained at the receiving point (terminal) are obtained by adding the received components (step S16), and the evaluation ends. For example, the evaluation device is received component _r v of each polarization obtained at the receiving point _(t), and _r h (t), transmission signal _s v _(t), from the transmitter to the terminal from the _s h (t) Evaluation of channel characteristics.

  Hereinafter, the process of each step in the evaluation method of the wireless communication system will be described in more detail.

(Process of step S11)
The evaluation device acquires radio wave scatterer information that is information about the radio wave scatterer. The radio scatterer information includes the number N of radio scatterers used in the simulation, the oblique angle α _n of the reflection surface with respect to the incident surface of the transmission signal for each radio scatterer (n = 1, 2,..., N), the radio wave Including the dielectric constant, permeability and dielectric constant of the scatterer. A predetermined value may be used as the number N of radio wave scatterers and the oblique angle α _n , or a value based on a random number generated using a random number generator may be used.

(Process of step S12)
The evaluation device acquires the propagation phase η _n of the path through each of the N radio wave scatterers. As the propagation phase η _n , a predetermined value may be used, or a value (−2π <η _n ≦ 2π) based on a random number generated using a random number generator may be used.

(Process of step S13)
The evaluation apparatus may use a predetermined value as the polarization conversion amount P _nh , or may use a value calculated by the following method. When calculating the polarization conversion amount P _nh , the evaluation device calculates the reflection coefficient of the TM wave component and the TE wave component for each radio wave scatterer, and calculates the TM wave component and the TE wave component after reflection from the reflection coefficient. The TE wave component and TM after reflection are calculated, and the polarization conversion amount P _nh is calculated by combining the components.

Transmission signals s _v (t) and s _h (t) transmitted at different polarization planes are reflected or diffracted by a building such as a building or the ground in a propagation path until they are received by the terminal. FIG. 2 is a diagram showing an outline of radio wave reflection. In FIG. 2, a medium I having dielectric constant, magnetic permeability and dielectric constant of ε ₁ , μ ₁ and σ _{1 and} a medium II having dielectric constant, magnetic permeability and dielectric constant of ε ₂ , μ ₂ and σ ₂ are in contact with each other. The case where electromagnetic waves are incident on the plane boundary at an incident angle θ _i is shown. When electromagnetic waves are incident on a plane boundary, reflected waves and transmitted waves are generated. When the xy plane is the incident surface, the Fresnel reflection coefficient is defined in each of the case where the electric field is parallel to the incident surface (TM incidence) and the case where the electric field is perpendicular to the incident surface (TE incidence). Equation (3) represents the reflection coefficient R _TM in the case of TM incidence, and Equation (4) represents the reflection coefficient R _TE in the case of TE incidence.

Note that predetermined values are used for the dielectric constant, the magnetic permeability, and the dielectric constant of each of the medium I and the medium II. Further, n in the expressions (3) and (4) is a relative complex refractive index of the medium II with respect to the medium I and is given by the expression (5).

However, in an actual propagation environment, the incident vector is dominant when it is oblique to the medium boundary. FIG. 3 is a diagram illustrating an example in which the incident vector is inclined with respect to the medium boundary surface. As shown in FIG. 3, consider the case where the electric field E ⁱ _theta, 2 field E ⁱ _phi perpendicular to the electric field E ⁱ _theta has simultaneously incident. Here, the electric field E ⁱ _θ and the electric field E ⁱ _φ are independent electric field components that are uncorrelated with each other. In the example shown in FIG. 3, the electric field E ⁱ _θ direction vector is the x-axis direction, and the direction perpendicular to the xz plane, which is the medium boundary surface, is the y-axis. At this time, as in the example shown in FIG. If the angle formed by the vector I from the incident point to the reflection point (the point where the x-axis, y-axis and z-axis intersect in FIG. 3) and the incident surface is α, (E ⁱ _θ , E ⁱ _φ ) and the TM component ( The relationship between E ⁱ _TM ) and the TE component (E ⁱ _TE ) is expressed by equation (6).

Here, when the electric field after reflection is considered in the same coordinate plane as the incident electric field (E ⁱ _θ , E ⁱ _φ ), similarly, the electric field components (E ^r _θ , E ^r _φ ) and the TM component (E ^r relationship between _TM) and TE component _{^(E r TE)} is represented by the formula (7).

Here, according to Fresnel's law, the relationship represented by Expression (8) is established between the incident wave and the reflected wave.

When (E ⁱ _TM , E ⁱ _TE ) is derived from Expression (6) and Expression (7) is substituted into Expression (8), Expression 9 is obtained.

Here, R ₁₁ , R ₁₂ , R ₂₁ and R ₂₂ in Formula (9) are represented by Formulas (10-1) and (10-2).

From Equations (3) and (4), R _TM ≠ R _TE , and when (E ⁱ _θ , E ⁱ _φ ) is obliquely incident on the incident surface at an angle α from Equation (9), its reflected wave component It can be seen that E ⁱ _θ and E ⁱ _φ are distributed to both (E ^r _θ , E ^r _φ ). Here, the case where the transmission signal includes two polarized waves has been described. However, even when the number of polarized waves is increased, the components are similarly distributed between the polarized waves.

Expressions (11-1) and (11-2) are obtained from Expression (9).

(R ₁₂ / R ₁₁ ) is the power ratio distributed from horizontal polarization to vertical polarization due to reflection by the radio wave scatterer. In addition, (R ₂₁ / R ₂₂ ) is a power ratio distributed from vertical polarization to horizontal polarization due to reflection by the radio wave scatterer. That is, (R ₁₂ / R ₁₁ ) and (R ₂₁ / R ₂₂ ) become the polarization conversion amount P _nh . The polarization conversion amount is a distribution ratio of components generated during reflection between vertical polarization and horizontal polarization.

The evaluation apparatus calculates the oblique angle α _n with respect to the incident surface in the path n that is reflected by the radio wave scatterer n and reaches the terminal, and the electric conductivity, magnetic permeability, and dielectric constant of the radio wave scatterer n are ε _n , μ _n , and σ _n . The polarization conversion amount P _nh is calculated for each radio wave scatterer. In the calculation of the polarization conversion amount P _nh , for example, air may be used as the other medium that forms the boundary surface between the radio wave scatterer and the medium, and the electric conductivity, magnetic permeability, and dielectric constant in the air may be used. Assuming a vacuum, the electric conductivity, magnetic permeability and dielectric constant in the vacuum may be used.

(Process of step S14)
Considering a quasi-static environment (f _d = 0) in which the terminal does not move for simplicity, s _nv (t), the vertical polarization component and the horizontal polarization component of the transmission signal reflected by the radio wave scatterer n, respectively, Let s _nh (t) be r _nv (t), r _nh (t), and r _nv (t), respectively, the vertical polarization component and horizontal polarization component of the received signal at the terminal of the path n that is reflected by the radio wave scatterer n and reaches the terminal. To do. In the radio wave scatterer model in the quasi-static environment, equations (12-1) and (12-2) are established. Note that η _n is a propagation phase in a path n that is reflected by the radio wave scatterer n and reaches the terminal.

In this radio wave scatterer model, it is assumed that the signal power is not lost due to reflection, and only the phase component rotates. Under this assumption, when considering that one polarization component is added to the other polarization component by power distribution by reflection, equations (13-1) and (13-2) are obtained. (R ₁₂ / R ₁₁ ) and (R ₂₁ / R ₂₂ ), which are the second term components of the formulas (13-1) and (13-2), are the polarization conversion amounts P _nh , respectively.

FIG. 4 is a diagram showing an outline of the radio wave scatterer model of the present embodiment represented by the equations (13-1) and (13-2). The transmission signal s (t) transmitted from the transmitter reaches the terminal after being reflected by each of the N radio scatterers. The vertical polarization component and the horizontal polarization component of the reflected wave reflected by the radio wave scatterer n are obtained by r _nv (t), r _nh (t), (n = 1, 2,..., N), respectively. The evaluation apparatus uses the equations (13-1) and (13-2) to calculate the vertical polarization component r _nv (t) and the horizontal polarization component r _nh (t) of the signal reaching the terminal for each radio wave scatterer. And calculate.

(Process of step S15)
The calculation of the Doppler fluctuation for each radio wave scatterer is performed based on, for example, the maximum Doppler fluctuation amount f _d given in advance. The evaluation apparatus uses a value {exp (jcos (β _n · f _d ) t)} based on the maximum Doppler variation f _d for the vertical polarization component r _nv (t) and the horizontal polarization component r _nh (t). The phase rotation amount due to Doppler fluctuation is calculated by multiplication. Here, β _n is a moving direction vector of the terminal, and a value given in advance may be used, or a random value obtained using a random number generator may be used.

(Process of step S16)
The evaluation apparatus performs addition processing on the reflected wave (r _nv (t), r _nh (t)) calculated for each radio wave scatterer, and the vertical polarization component r _v (t of the signal received at the terminal ) And the horizontal polarization component r _h (t). The vertical polarization component r _v (t) and the horizontal polarization component r _h (t) are expressed by equations (14-1) and (14-2).

  With the above processing, the evaluation device can perform simulation by using a model that reflects the power exchange (power distribution) between polarized waves due to the polarization exchange effect, and perform the simulation considering the influence of the correlation between polarizations. Can do. Also, in this simulation, the received signal and channel characteristics at the terminal are calculated taking into account the polarization deviation caused by the reflection by the radio wave scatterer in the propagation path from the transmitter to the terminal. It can be used to improve the system. For example, when a transmission / reception antenna corresponding to horizontal polarization and vertical polarization is fixed, each component is determined based on the correlation between the horizontal polarization component and the vertical polarization component in the received signal obtained on the reception side. Diversifying and synthesizing can obtain a diversity effect and improve transmission quality.

FIG. 5 is a block diagram illustrating a configuration example of the evaluation apparatus 1 of the wireless communication system in the present embodiment. The evaluation apparatus 1 inputs transmission signals s _nv (t) and s _nh (t) that are a combination of vertical polarization and horizontal polarization, and evaluates channel characteristics in an out-of-sight multiwave environment to which a radio scatterer model is applied. calculate. The evaluation apparatus 1 includes a radio wave scatterer information acquisition unit 11, a propagation phase acquisition unit 12, a polarization conversion amount calculation unit 13, a reception component calculation unit 14, a Doppler fluctuation calculation unit 15, an addition processing unit 16, A channel characteristic calculation unit 17.

  The radio wave scatterer information acquisition unit 11 acquires radio wave scatterer information, and outputs the acquired radio wave scatterer information to the polarization conversion amount calculation unit 13. The radio scatterer information acquisition unit 11 may acquire the radio scatterer information by reading the radio scatterer information from an external storage device, or generates radio scatterer information with a value based on a random number generated using a random number generator. Alternatively, radio wave scatterer information input by a user who uses the evaluation device 1 may be acquired. The propagation phase acquisition unit 12 acquires the propagation phase of each radio wave scatterer and outputs the acquired propagation phase to the reception component calculation unit 14. Similarly to the radio wave scatterer information acquisition unit 11, the propagation phase acquisition unit 12 may acquire the propagation phase by reading the propagation phase from an external storage device, or may be a value based on a random number generated using a random number generator. A propagation phase may be generated, or a propagation phase input by a user using the evaluation device 1 may be acquired.

The polarization conversion amount calculation unit 13 calculates the polarization conversion amount P _nh for each radio wave scatterer based on the radio wave scatterer information input from the radio wave scatterer information acquisition unit 11. The polarization conversion amount calculation unit 13 outputs the calculated polarization conversion amount P _nh of each radio wave scatterer to the reception component calculation unit 14. Based on the input transmission signals s _nv (t) and s _nh (t) and the polarization conversion amount P _nh calculated by the polarization conversion amount calculation unit 13, the reception component calculation unit 14 The reception components of vertical polarization and horizontal polarization are calculated for each radio wave scattering object. The reception component calculation unit 14 outputs the calculated reception components of vertical polarization and horizontal polarization to the Doppler fluctuation calculation unit 15.

The Doppler fluctuation calculation unit 15 calculates, for each radio wave scattering object, a phase rotation amount due to Doppler fluctuations with respect to the reception components of the vertical polarization and the horizontal polarization calculated by the reception component calculation unit 14. The Doppler fluctuation calculation unit 15 outputs the reception components of the vertical polarization and the horizontal polarization to which the phase rotation due to the Doppler fluctuation is added to the addition processing unit 16. The addition processing unit 16 adds the vertical polarization and horizontal polarization for each radio wave scatterer calculated by the Doppler fluctuation calculation unit 15 and the respective reception components, and receives each polarization obtained at the reception point (terminal). Components r _v (t) and r _h (t) are calculated. The addition processing unit 16 outputs the calculated reception components r _v (t) and r _h (t) to the channel characteristic calculation unit 17.

The channel characteristic calculation unit 17 transmits the transmission signal based on the reception components r _v (t) and r _h (t) calculated by the addition processing unit 16 and the transmission signals s _nv (t) and s _nh (t). The channel characteristics in the transmission environment from the transmission point to the reception point are calculated. The channel characteristic calculation unit 17 outputs channel information indicating the calculated channel characteristic to an external device.

  According to the evaluation apparatus 1 of the present embodiment, channel characteristics that change due to the correlation existing between polarizations can be obtained by simulation using a model that reflects power exchange between polarizations due to the polarization exchange effect. Accuracy can be improved.

  In addition, in this embodiment, although the structure which acquires separately the electromagnetic wave scatterer information and the propagation phase of each electromagnetic wave scatterer was shown, you may include a propagation phase in electromagnetic wave scatterer information. In this case, step S12 in the evaluation method of the wireless communication system is omitted, and the propagation phase acquisition unit 12 in the evaluation apparatus 1 is omitted.

  You may make it implement | achieve all or one part of the evaluation apparatus 1 in embodiment mentioned above with a computer. For example, it is realized by recording a program for realizing each component of the evaluation apparatus 1 on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium. Also good. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Further, the “computer-readable recording medium” is a program that dynamically holds a program for a short time, like a communication line when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client in that case may be included and a program held for a certain period of time. In addition, this program may be for realizing some of the above-described components, and further, the above-described components can be realized in combination with a program already recorded in the computer system. Alternatively, it may be realized using hardware such as PLD (Programmable Logic Device) or FPGA (Field Programmable Gate Array).

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

  It can also be applied to applications where it is essential to improve the accuracy of simulation for a wireless communication system that performs transmission by combining different polarizations.

DESCRIPTION OF SYMBOLS 1 ... Evaluation apparatus 11 ... Radio scatterer information acquisition part 12 ... Propagation phase acquisition part 13 ... Polarization conversion amount calculation part 14 ... Reception component calculation part 15 ... Doppler fluctuation calculation part 16 ... Addition processing part 17 ... Channel characteristic calculation part

Claims (5)

An evaluation method for a wireless communication system that performs transmission by combining different polarizations,
Radio wave scatterer information acquisition step for acquiring radio wave scatterer information related to the radio scatterer in a multi-wave environment outside the line of sight between the transmission point and the reception point;
A polarization conversion amount indicating a distribution ratio of components between the different polarized waves when a transmission signal transmitted from the transmission point is reflected in the radio scatterer is calculated for each radio scatterer based on the radio scatterer information. A step of calculating the amount of polarization conversion;
Based on the polarization conversion amount calculated in the polarization conversion amount calculation step and the radio wave scatterer information, the reception component of each of the different polarizations at the reception point is calculated for each reflected wave at the radio wave scatterer. Receiving component calculation step,
A Doppler fluctuation calculating step for calculating, for each radio wave scatterer, a phase rotation amount due to Doppler fluctuation received by the reflected wave reflected by the radio wave scatterer by moving to the reception point;
An addition processing step of adding each of the different polarized waves after adding the phase rotation amount calculated by the Doppler fluctuation calculation step to the reception component calculated by the reception component calculation step;
A method for evaluating a wireless communication system comprising: In the polarization conversion amount calculating step,
Based on the oblique angle of the incident surface of the transmission signal with respect to the reflecting surface in the radio wave scatterer included in the radio wave scatterer information and the dielectric constant of the radio wave scatterer, the TM wave component parallel to the incident surface and the incident surface Calculate the reflection coefficient with the vertical TE wave component,
Calculating the TM wave component and the TE wave component of the reflected wave reflected by the radio wave scatterer using the reflection coefficient of the TM wave component and the TE wave component;
Calculating the polarization conversion amount by combining the TM wave component and the TE wave component of the calculated reflected wave;
The wireless communication system evaluation method according to claim 1. A channel characteristic calculation step of calculating a channel characteristic between the transmission point and the reception point based on the reception component and the transmission signal for each different polarization at the reception point calculated by the addition processing step; Further having
The method for evaluating a wireless communication system according to claim 1 or 2. An evaluation apparatus for a wireless communication system that performs transmission by combining different polarizations,
A radio wave scatterer information acquisition unit for acquiring radio wave scatterer information relating to the radio scatterer in a multi-wave environment outside the line of sight between the transmission point and the reception point;
A polarization conversion amount indicating a distribution ratio of components between the different polarized waves when a transmission signal transmitted from the transmission point is reflected in the radio scatterer is calculated for each radio scatterer based on the radio scatterer information. A polarization conversion amount calculation unit;
Based on the polarization conversion amount calculated by the polarization conversion amount calculation unit and the radio wave scatterer information, the reception component of each of the different polarizations at the reception point is calculated for each reflected wave at the radio wave scatterer. A reception component calculation unit;
A Doppler fluctuation calculation unit for calculating, for each radio wave scatterer, a phase rotation amount due to Doppler fluctuations received by the reflected wave reflected by the radio wave scatterer by moving to the reception point;
An addition processing unit for adding each of the different polarizations after adding the phase rotation amount calculated by the Doppler fluctuation calculation unit to the reception component calculated by the reception component calculation unit;
An evaluation apparatus comprising:     The program for making a computer perform the evaluation method of the radio | wireless communications system as described in any one of Claims 1-3.

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