JP5421850B2 - Multi-antenna evaluation signal transmission system and multi-antenna evaluation signal transmission method - Google Patents

Description

  The present invention relates to a multi-antenna evaluation signal transmission system and a multi-antenna evaluation signal transmission method for evaluating overall radio performance including an antenna of a communication device that supports MIMO.

  In general, performance evaluation of a communication antenna is performed by measuring radiation directivity in an anechoic chamber. In addition, an evaluated terminal including at least two antennas (multi-antennas) used for MIMO transmission or the like needs to evaluate not only the radiation directivity of each antenna but also the spatial phase between the antennas. In this case, it is necessary to evaluate the performance of the terminal to be evaluated in a measurement environment that takes into account the angular spread of incoming waves with respect to the multi-antenna as in the actual propagation environment. As a conventional multi-antenna evaluation signal transmission system that simulates the angular spread of an incoming wave, for example, the systems described in Patent Documents 1 and 2 and the amplitude phase control device (fading emulator) described in Non-Patent Document 1 are used. There is a method for transmitting a signal through the network.

  FIG. 10 is an example of the overall configuration of a multi-antenna evaluation signal transmission system 10 configured based on the prior art. FIG. 11 is a functional block diagram of the multi-antenna evaluation signal transmission system 10. The multi-antenna evaluation signal transmission system 10 includes a fading emulator 11 and four transmission antennas 121 to 124. The first transmission antenna 121 includes a vertical polarization element 121v and a horizontal polarization element 121h, the second transmission antenna 122 includes a vertical polarization element 122v and a horizontal polarization element 122h, and a third transmission antenna 123. Includes a vertical polarization element 123v and a horizontal polarization element 123h, and the fourth transmission antenna 124 includes a vertical polarization element 124v and a horizontal polarization element 124h.

  When evaluating the performance of the multi-antenna of the terminal 80 to be evaluated, the correlation characteristic of the signal received by each element of the multi-antenna affects the final received signal characteristic. Therefore, in order to evaluate the performance of the multi-antenna, an evaluation signal transmission system that takes into account the angular spread of the incoming wave to the multi-antenna is required. Therefore, for the purpose of simulating an environment in which radio waves arrive with a wide angle with respect to the evaluated terminal 80, N (at least four, FIG. 10 shows a configuration example in the case of four) transmitting antennas are evaluated. It arrange | positions on the periphery of the predetermined | prescribed radius (at least 5 times the measurement wavelength) centering on the terminal 80. FIG. For example, the first transmission antenna 121 and the third transmission antenna 123 are arranged in the clockwise direction with respect to the reference point on the circumference, and the second transmission antenna 122 and the fourth transmission antenna are arranged in the order 124. Arrange clockwise. Further, each transmission antenna is arranged at substantially the same height as the terminal 80 to be evaluated.

Fading Emulator 11 is uncorrelated signal sequences s ₁ ~s _n of different n-number generated by the serving signal generator 70 of the base station (n ≧ 1) is input, all of the N transmitting antennas Uncorrelated signal sequences S _{1 to} S _{2N corresponding} to the number of polarization elements (2N) are output from 2N output ports # 1 to # 8, respectively. More specifically, when the fading emulator 11 is the signal sequence s ₁ ~s _n is input, and divides each into 2N pieces _{([s 1,1, s 1,2,} ···, s 1,2N] , [s _2,1 , s _2,2 , ..., s _2,2N ], ..., [s _{n, 1} , s _{n, 2} , ..., s _{n, 2N} ]), 2N sets Fading generation sections # 1 (-1, -2,..., -N), # 2 (-1, -2, ..., -n), ..., # 2N (-1, -2 ,..., -N), [s _1,1 , s _2,1 , ..., s _{n, 1} ], [s _1,2 , s _2,2 , ..., s _{n , 2} ], [s _1,2N , s _2,2N ,..., _Sn , _2N ] and combining the outputs to obtain M uncorrelated signal sequences S _{1 to} S _2N . Generate and output. FIGS. 10 and 11 show the case of n = 2 and N = 4. Therefore, the uncorrelated signal sequences s ₁ and s ₂ are input to the fading emulator 11 and output from the output ports # 1 to # 8. Uncorrelated signal sequences S _{1 to} S ₈ are output. The uncorrelated signal sequences S ₁ , S ₂ , S ₃ , S ₄ , S ₅ , S ₆ , S ₇ , and S ₈ are the vertical polarization element 121v, the horizontal polarization element 121h, and the vertical polarization element, respectively. The element 122v, the horizontal polarization element 122h, the vertical polarization element 123v, the horizontal polarization element 123h, the vertical polarization element 124v, and the horizontal polarization element 124h are input and transmitted.

  Each transmitted signal sequence is received by the evaluated terminal 80, and the reception result is evaluated. Here, if the terminal 80 to be evaluated is mounted on a turntable 90 that can be rotated in the horizontal direction, the characteristics of the terminal to be evaluated at various angles can be easily measured by rotating the turntable 90. it can.

JP 2005-303476 A JP 2005-227213 A

Pekka Kysti, Jukka-Pekka Nuutinen, and Petteri Heino, "Reconstruction and measurement of Spatial Channel Model for OTA," 3GPP TSG RAN WG4 # 51bis meeting document, 2009

  When generating a simulated environment in which radio waves having an angular spread arrive at the terminal to be evaluated using N transmitting antennas, the signal series radiated from each transmitting antenna is generally uncorrelated. However, when the transmitting antenna has a dual polarization configuration, the number of uncorrelated signals is twice as many as the number of transmitting antennas. Therefore, the fading emulator used for generating uncorrelated signals has the output ports for that number. There must be. However, since the fading emulator having a large number of output ports performs very complicated amplitude phase control and requires a number of fading generation units corresponding to the number of output ports, it is expensive and the scale of the apparatus increases. In fact, even with the simple configuration illustrated in FIGS. 10 and 11, it is necessary to use a fading emulator having at least eight output ports.

  It is an object of the present invention to reduce the number of required output ports of a fading emulator for generating an uncorrelated signal used for evaluation of a terminal to be evaluated equipped with a multi-antenna, thereby reducing the system cost and the scale of the system. It is an object to provide a signal transmission system for use and a signal transmission method for multi-antenna evaluation.

  The multi-antenna evaluation signal transmission system according to the present invention is a multi-antenna evaluation signal transmission system for transmitting an evaluation signal sequence to an evaluated terminal having two or more antennas, and signals that are not correlated with each other. Fading emulator having M (M ≧ 2) output ports for outputting a sequence, N (N ≧ 2M) transmission antennas each including a vertical polarization element and a horizontal polarization element, and adjacent transmission antennas Distribute each output of the fading emulator to each of the same polarization element and each polarization element of the same transmitting antenna so that signal sequences from different output ports of the fading emulator are input. M dividers that are input to each polarization element of N transmission antennas, and 2N phase shifts that are inserted between the divider and each polarization element. When, with the correlation of each signal series transmitted from each polarization element of the N transmit antennas, setting the phase value of each phase shifter so it is minimized at the location of the evaluation device.

  In addition, the multi-antenna evaluation signal transmission method of the present invention is directed to N (N ≧ 2M) including a vertically polarized wave element and a horizontally polarized wave element for a terminal to be evaluated having two or more antennas. A multi-antenna evaluation signal transmission method for transmitting an evaluation signal sequence from a transmission antenna, comprising: an uncorrelated signal generation step for generating M (M ≧ 2) signal sequences that are uncorrelated with each other; and an adjacent transmission antenna The signal sequences generated in the uncorrelated signal generation step are set to N so that uncorrelated signal sequences are input to each of the same polarization element and each polarization element of the same transmission antenna. The distribution step of distributing to each polarization element of the transmission antennas and the correlation between the signal sequences transmitted from the polarization elements of the N transmission antennas are minimized at the position of the evaluated terminal. In addition, A phase value setting step for setting a phase value for the signal sequence, and a transmission step for transmitting each signal sequence for which the phase value has been set in the phase value setting step from each polarization element of the N transmitting antennas. To do.

  According to the multi-antenna evaluation signal transmission system and multi-antenna evaluation signal transmission method of the present invention, the number of necessary output ports of the fading emulator for generating the uncorrelated signal used for the evaluation of the evaluated terminal having the multi-antenna is reduced. Therefore, the system cost and the system scale can be reduced.

The figure which shows the example of whole structure of the signal transmission system for multi-antenna evaluation of this invention. The functional block diagram of the signal transmission system for multi-antenna evaluation of this invention. The figure which shows the example of a processing flow of the signal transmission system for multi-antenna evaluation of this invention. The figure which shows the arrangement image of each transmission antenna. The figure which shows the example of allocation of the fading emulator output to each transmission antenna. The figure which shows the example of a phase adjustment with respect to the signal transmitted from each transmission antenna. The figure which shows the cluster model obtained by adjustment of the transmission power of each transmission antenna. The figure which shows the simulation result of the phase characteristic of RMS of the correlation coefficient and received power of the received signal series from each transmitting antenna. The figure which shows the comparison with this invention and the prior art of the correlation coefficient of each signal series in the position of a to-be-evaluated terminal. The figure which shows the example of whole structure of the signal transmission system for conventional multi-antenna evaluation. The functional block diagram of the conventional signal transmission system for multi-antenna evaluation.

  Hereinafter, embodiments of the present invention will be described in detail.

  As described above, when generating a simulated environment in which radio waves having an angular spread arrive at the terminal to be evaluated using N transmission antennas, the signal sequence radiated from each transmission antenna is generally uncorrelated. It is. However, the radio wave arrival simulation environment having an angular spread at the position of the evaluated terminal does not necessarily have to be generated by transmitting an uncorrelated signal sequence from all transmission antennas. Even if the signal sequence transmitted from each polarization element of each transmission antenna is correlated at the time of radiating from the antenna, each signal sequence generated by the fading emulator for each polarization of each transmission antenna Devise how to assign to the elements, and set the phase difference appropriately for each polarization element of each transmitting antenna, so that the correlation is minimized when reaching the terminal to be evaluated Can also be generated. The multi-antenna evaluation signal transmission system 100 of the present invention realizes a reduction in the number of required output ports of the fading emulator based on such a principle.

  FIG. 1 is an overall configuration example of a multi-antenna evaluation signal transmission system 100 according to the present invention, and FIG. 2 is a functional block diagram of the multi-antenna evaluation signal transmission system 100. FIG. 3 is a processing flow of the multi-antenna evaluation signal transmission system 100. The multi-antenna evaluation signal transmission system 100 is a system for transmitting a signal sequence for evaluation toward an evaluated terminal having a multi-antenna. The multi-antenna evaluation signal transmission system 100 includes a fading emulator having M (M ≧ 2) output ports that output uncorrelated signal sequences, N (N ≧ 2M) transmission antennas, and M number of transmission antennas. A distributor and 2N phase shifters. Hereinafter, for convenience of explanation, a case where M = 2 and N = 4 will be described.

The fading emulator 110 receives, for example, two different uncorrelated signal sequences s ₁ and s ₂ generated by the signal generator 70 serving as a base station, and receives two uncorrelated signal sequences S ₁ and S 2. ₂ are output from the output ports # 1 and # 2, respectively (S1). Specifically, when the signal sequences s ₁ and s ₂ are input to the fading emulator 11, each of them is divided into two ([s _1,1 , s _1,2 ], [s _2,1 , s _{2 , 2} ]) and [s _1,1 , s _2,1 ], [s _{1, 2} , s _2,2 ] are input, and their outputs are combined to generate and output _two uncorrelated signal sequences S ₁ and S ₂ .

  As with the conventional multi-antenna evaluation signal transmission system 10, the four transmission antennas 121 to 124 are configured such that the first transmission antenna 121 transmits the vertical polarization element 121 v and the horizontal polarization element 121 h to the second transmission antenna. The antenna 122 is a vertical polarization element 122v and a horizontal polarization element 122h, the third transmission antenna 123 is a vertical polarization element 123v and a horizontal polarization element 123h, and the fourth transmission antenna 124 is a vertical polarization. Element 124v and horizontal polarization element 124h. As described in the background art, when evaluating the performance of the multi-antenna of the terminal 80 to be evaluated, the correlation characteristics of signals received by the elements of the multi-antenna affect the final received signal characteristics. Therefore, in order to evaluate the performance of the multi-antenna, an evaluation signal transmission system that takes into account the angular spread of the incoming wave to the multi-antenna is required. Therefore, for the purpose of simulating an environment in which radio waves arrive with an angular spread with respect to the terminal 80 to be evaluated, N (four in this embodiment) transmission antennas are set to a predetermined center around the terminal 80 to be evaluated. It arrange | positions on the periphery of a radius (at least 5 times the measurement wavelength). For example, the first transmission antenna 121 and the third transmission antenna 123 are arranged clockwise in this order with respect to the reference point on the circumference, and the second transmission antenna 122 and the fourth transmission antenna are arranged counterclockwise. Arrange in order 124. Further, each transmission antenna is arranged at substantially the same height as the terminal 80 to be evaluated. A specific example of the arrangement of each transmission antenna is shown in FIG. FIG. 4 is a plan view of the transmission antennas 121 to 124 and the terminal 80 to be evaluated. For example, considering the approximation of a cluster model having an arbitrary angular spread A degree, when the clockwise direction is a negative angle and the counterclockwise direction is a positive angle with respect to the reference point (0 degree) on the circumference. The first transmitting antenna 121 is -A / 2 degrees, the second transmitting antenna 122 is + A / 2 degrees, the third transmitting antenna 123 is -3 A / 2 degrees, and the fourth transmitting antenna 124 is +3 A / 2 degrees. It arranges in each position.

Distributors 131 and 132 are configured such that uncorrelated signal sequences S ₁ and S ₂ output from fading emulator 110 are respectively the same polarization element of adjacent transmission antennas and each polarization element of the same transmission antenna. (S2). Specifically, for example, when the transmission antennas are arranged as shown in FIG. 4, the signal series S ₁ includes the vertical polarization element 121 v of the transmission antenna 121 and the vertical polarization of the transmission antenna 124 as shown in FIG. The four distributions are performed so as to be input to the wave element 124v, the horizontal polarization element 122h of the transmission antenna 122, and the horizontal polarization element 123h of the transmission antenna 123. Further, the signal series S _{2 includes} a vertically polarized wave element 122v of the transmission antenna 122, a vertical polarized wave element 123v of the transmission antenna 123, a horizontal polarization element 121h of the transmission antenna 121, and a horizontal polarization element of the transmission antenna 124. Divide into 4 so as to be input to 124h. By distributing in this way, the signal series input to each of the same polarization element of the adjacent transmitting antenna and each of the polarization elements of the same antenna become uncorrelated with each other.

  The phase shifters 141v, 144v, 142h, and 143h are disposed between the distributor 131 and the vertical polarization element 121v, the vertical polarization element 124v, the horizontal polarization element 122h, and the horizontal polarization element 123h, respectively. Is inserted. Further, phase shifters 142v, 143v, 141h, respectively, are provided between the distributor 132 and the vertical polarization element 122v, the vertical polarization element 123v, the horizontal polarization element 121h, and the horizontal polarization element 124h. And 144h are inserted.

For example, when the signal sequences S ₁ and S ₂ are distributed to the transmission antennas as shown in FIG. 5, the respective phase shifters are set as follows (see FIG. 6A) (S3). With reference to the phase of the signal sequence radiated from the vertical polarization element 121v of the first transmitting antenna 121, the phase shifter 144v sets the phase of the signal sequence radiated from the vertical polarization element 124v to a1 degree or -a1. The phase shifter 142h sets the phase of the signal sequence radiated from the horizontal polarization element 122h to a2 degrees or -a2 degrees, and the phase shifter 143h sets the phase of the signal sequence radiated from the horizontal polarization element 123h to a3. Set to degrees or -a3 degrees respectively. Here, a1 ≠ a2 ≠ a3 ≠ 0. The phase shifter 141h sets the phase of the signal sequence radiated from the horizontal polarization element 121h to α degrees, and the phase shifter 144h sets the phase of the signal sequence radiated from the horizontal polarization element 124h to α + b1 degrees or α -B1 degrees, the phase shifter 142v sets the phase of the signal sequence radiated from the vertical polarization element 122v to α + b2 degrees or α-b2 degrees, and the phase shifter 143v sets the phase of the signal sequence radiated from the vertical polarization element 123v. The phase is set to α + b3 degrees or α−b3 degrees, respectively. Here, since the signal sequences S ₁ and S ₂ are uncorrelated, α may be an arbitrary value. Further, b1 ≠ b2 ≠ b3 ≠ 0.

  The phase adjustment needs to be performed in the entire band of the test frequency (for example, 3.84 MHz in the case of an arbitrary channel of WCDMA). Accordingly, it is necessary to unify all the phase characteristics with respect to the frequency axis in the path from the output port of the fading emulator to the transmitting antenna. The most common method for unifying is to unify phase characteristics for components (cables, phase shifters, variable attenuators, distributors, transmission antennas) constituting all paths.

  The signal sequence whose phase is adjusted by the phase shifter is transmitted from each polarization element of each transmission antenna (S4), and the evaluated terminal 80 receives them and evaluates the reception result. At this time, by appropriately setting the values of a1, a2, a3, b1, b2, and b3 by each phase shifter, the correlation of each signal sequence received by the evaluated terminal 80 can be minimized. it can. If the evaluated terminal 80 is mounted on a turntable 90 that can be rotated in the horizontal direction, the characteristics of the evaluated terminal at various angles can be easily measured by rotating the turntable 90. .

As described above, the uncorrelated signal sequences S ₁ and S ₂ output from the fading emulator 110 are respectively input to the same polarization element of the adjacent transmission antenna and each polarization element of the same transmission antenna. Each signal sequence is radiated from each polarization element of each transmission antenna by appropriately setting the values of a1, a2, a3, b1, b2, b3 by each phase shifter. Even if there is a correlation between them, the radio wave arrival simulation environment having an angular spread at the position of the evaluated terminal is generated by minimizing the correlation of each signal sequence when reaching the evaluated terminal. be able to. Therefore, when a system is configured by using four dual-polarized transmission antennas, an 8-port fading emulator has been conventionally required. However, according to the configuration of the present invention, a 2-port fading emulator is sufficient. Therefore, the system cost can be reduced and the scale of the system can be reduced.

  If a plurality of transmission antennas are used and an arbitrary radio wave distribution (for example, a cluster model having an angular spread A degree) is to be approximated with respect to the terminal 80 to be evaluated, distribution is performed in order to adjust the transmission power from each transmission antenna. Further, variable attenuators 151v, 154v, 152h, and 153h are respectively provided between the attenuator 131 and the vertical polarization element 121v, the vertical polarization element 124v, the horizontal polarization element 122h, and the horizontal polarization element 123h. In addition, the variable attenuators 152v, 153v, and 151h are further provided between the distributor 132 and the vertical polarization element 122v, the vertical polarization element 123v, the horizontal polarization element 121h, and the horizontal polarization element 124h, respectively. , And 154h may be inserted. For example, when four transmission antennas are arranged as shown in FIG. 4, the transmission power of the first transmission antenna 121 and the transmission power of the second transmission antenna 122 are variable attenuators 151v and 151h as shown in FIG. , 152v, and 152h, the transmission power of the third transmission antenna 123 and the transmission power of the fourth transmission antenna 124 are adjusted by the variable attenuators 153v, 153h, 154v, and 154h. The power is set to 12 dB lower than the transmitting antennas 121 and 122 (S5). Thereby, a cluster model having a Laplace distribution with an RMS angular spread of A degrees can be approximated.

When each transmitting antenna is arranged symmetrically with respect to a reference point on the circumference as shown in FIG. 4, and the signal sequences S ₁ and S ₂ are distributed to each transmitting antenna as shown in FIG. The phase shifter can also be set as follows (see FIG. 6B).

For the vertical polarization of the first transmission antenna 121 on the basis of the phase of the signal sequence radiated from the horizontal polarization element 123h of the third transmission antenna 123 and the vertical polarization element 124v of the fourth transmission antenna 124 The phase of the signal sequence radiated from the element 121v is a1 ′ degree or −a1 ′ degree (a1 ′ ≠ 0), and the phase of the signal sequence radiated from the horizontal polarization element 122h of the second transmitting antenna 122 is −a1 ′. And the phase of the signal sequence radiated from the vertical polarization element 123v of the third transmission antenna 123 and the horizontal polarization element 124h of the fourth transmission antenna 124 is set to α degrees. The phase of the signal sequence radiated from the horizontal polarization element 121h of the first transmitting antenna 121 is set to α−b1 ′ degrees or α + b1 ′ (b1 ′ ≠ 0) degrees, and the vertical deviation of the second transmitting antenna 122 is set. Emitted from wave element 122v Setting the phase of the signal sequence to the alpha + b1 'degree or alpha-b1' of. Here, since the signal sequences S ₁ and S ₂ are uncorrelated, α may be an arbitrary value.

  As described above, the correlation between the signal sequences received by the evaluated terminal 80 can also be minimized by appropriately setting the values of a1 ′ and b1 ′ of each phase shifter.

FIG. 8A shows the RMS simulation result of the correlation coefficient of the received signal sequence from each transmitting antenna when a1 ′ and b1 ′ are changed to 0 to 180 degrees with the same value. The simulation results are shown in FIG. From this simulation, it can be seen that both the correlation coefficient and the power are minimized around 135 degrees. Therefore, by setting each phase shifter as shown in FIG. 6C, the correlation of each signal sequence can be minimized.
<Confirmation of effect>
FIG. 9 shows the correlation coefficient (◯ mark) according to the configuration of the present invention shown in FIG. 1 and the correlation coefficient (□ in the configuration according to the prior art shown in FIG. 10 for each signal sequence received by the terminal 80 to be evaluated. Comparison with) is shown. The horizontal axis indicates the direction of the terminal 80 to be evaluated, the front direction (the side connecting the two antennas of the terminal 80 to be evaluated is the base, and the reference point on the circumference where each transmitting antenna is arranged is the top. This is the rotation angle of the turntable 90 when the direction in which the isosceles triangle is formed is 0 degree. Further, (a) to (c) are cases where the intervals between the two antennas of the terminal 80 to be evaluated are 0.3λ, 0.5λ, and 0.7λ (λ is a measurement wavelength), respectively. As can be seen from this measurement result, it can be seen that there is no significant difference between the correlation coefficients of the signal sequences received by the terminal 80 to be evaluated between the configuration of the present invention and the configuration of the prior art.

  Therefore, according to the signal transmission system for multi-antenna evaluation of the present invention, it is possible to generate a radio wave arrival simulation environment having an angular spread similar to that of the prior art using a fading emulator having fewer output ports than the conventional configuration. As a result, the system cost can be reduced and the scale of the system can be reduced.

  The function sharing of each component of the signal transmission system for multi-antenna evaluation of the present invention described above is not limited to the function sharing shown in each embodiment, and can be appropriately changed without departing from the present invention. is there. In addition, the processing shown in each embodiment is not only executed in time series according to the order of description, but is also executed in parallel or individually as required by the processing capability of each component that executes the processing or as necessary. Also good.

10, 100 Multi-antenna evaluation signal transmission system 11, 110 Fading emulator 70 Signal generator 80 Evaluated terminal 90 Turntable 121-124 Transmitting antenna 121v-124v Vertical polarization element 121h-124h Horizontal polarization element 131, 132 Dividers 141v to 144v, 141h to 144h Phase shifters 151v to 154v, 151h to 154h Variable attenuators

Claims (8)

A multi-antenna evaluation signal transmission system for transmitting a signal sequence for evaluation toward an evaluated terminal having two or more antennas,
A fading emulator having M (M ≧ 2) output ports that output uncorrelated signal sequences;
N (N ≧ 2M) transmission antennas comprising vertical polarization elements and horizontal polarization elements;
Each of the fading emulators is arranged so that signal sequences from different output ports of the fading emulator are input to each of the polarization elements of the adjacent transmission antenna and each polarization element of the same transmission antenna. M distributors that distribute outputs and input to the polarization elements of the N transmitting antennas;
2N phase shifters inserted between the distributor and each polarization element;
Multi-antenna evaluation for setting the phase value of each phase shifter so that the correlation of each signal sequence transmitted from each polarization element of N transmit antennas is minimized at the position of the evaluated terminal Signal transmission system. The signal transmission system for multi-antenna evaluation according to claim 1,
A multi-antenna evaluation signal transmission system further comprising 2N variable attenuators inserted between the distributor and each polarization element. The multi-antenna evaluation signal transmission system according to claim 1 or 2,
M = 2, N = 4,
Each transmission antenna is arranged in the order of the first transmission antenna and the third transmission antenna in the clockwise direction with respect to the reference point on the circumference on the circumference around the terminal to be evaluated, and in the counterclockwise direction. Arranged in the order of the second transmission antenna, the fourth transmission antenna,
The first signal sequence from the first output port of the fading emulator is input to the vertical polarization elements of the first and fourth transmission antennas and the horizontal polarization elements of the second and third transmission antennas,
The second signal series from the second output port of the fading emulator is input to the vertical polarization elements of the second and third transmission antennas and the horizontal polarization elements of the first and fourth transmission antennas,
With each phase shifter, the phase of the signal sequence radiated from the vertical polarization element of the fourth transmission antenna is defined as a1 on the basis of the phase of the signal series radiated from the vertical polarization element of the first transmission antenna. Degree or -a1 degree, the phase of the signal sequence radiated from the horizontal polarization element of the second transmission antenna is a2 degree or -a2 degree, the phase of the signal series radiated from the horizontal polarization element of the third transmission antenna Is set to a3 degrees or -a3 degrees (a1 ≠ a2 ≠ a3 ≠ 0), and the phase of the signal sequence radiated from the horizontal polarization element of the first transmitting antenna is set to α degrees (α is arbitrary) The phase of the signal sequence radiated from the horizontal polarization element of the fourth transmission antenna is α + b1 degrees or α−b1 degrees, and the phase of the signal series radiated from the vertical polarization element of the second transmission antenna is α + b2 degrees. Alternatively, α−b2 degrees, and the phase of the signal sequence radiated from the vertical polarization element of the third transmitting antenna is α + b3 Degree or α−b3 degrees (b1 ≠ b2 ≠ b3 ≠ 0). The multi-antenna evaluation signal transmission system. The multi-antenna evaluation signal transmission system according to claim 1 or 2,
M = 2, N = 4,
Each transmitting antenna has a center angle of -A / 2 degrees (A is arbitrary) with respect to a reference point on the circumference on the circumference centered on the terminal to be evaluated, and the second Are arranged such that the transmitting antenna has a central angle of A / 2 degrees, the third transmitting antenna has a central angle of -3A / 2 degrees, and the fourth transmitting antenna has a central angle of 3A / 2 degrees. ,
The first signal sequence from the first output port of the fading emulator is input to the vertical polarization elements of the first and fourth transmission antennas and the horizontal polarization elements of the second and third transmission antennas,
The second signal series from the second output port of the fading emulator is input to the vertical polarization elements of the second and third transmission antennas and the horizontal polarization elements of the first and fourth transmission antennas,
With each phase shifter, the vertical polarization of the first transmission antenna is based on the phase of the signal sequence radiated from the horizontal polarization element of the third transmission antenna and the vertical polarization element of the fourth transmission antenna. The phase of the signal sequence radiated from the element for use is a1 ′ degree or −a1 ′ degree (a1 ′ ≠ 0), and the phase of the signal series radiated from the horizontal polarization element of the second transmitting antenna is −a1 ′ degree or a1 ′ degree, and the phase of the signal sequence radiated from the vertical polarization element of the third transmission antenna and the horizontal polarization element of the fourth transmission antenna is set to α degree (α is arbitrary), The phase of the signal sequence radiated from the horizontal polarization element of the first transmission antenna is set to α−b1 ′ degree or α + b1 ′ (b1 ′ ≠ 0) degree, and from the vertical polarization element of the second transmission antenna. A signal transmission system for multi-antenna evaluation that sets the phase of a radiated signal sequence to α + b1 ′ degrees or α−b1 ′ degrees. Multi-antenna evaluation for transmitting a signal sequence for evaluation from N (N ≧ 2M) transmission antennas each including an element for vertical polarization and an element for horizontal polarization toward a terminal to be evaluated including two or more antennas A signal transmission method for
An uncorrelated signal generating step for generating M (M ≧ 2) signal sequences that are uncorrelated with each other;
Each generated in the uncorrelated signal generation step so that a non-correlated signal sequence is input to each of the same polarization element of the adjacent transmission antenna and each of the polarization elements of the same transmission antenna. A distribution step of distributing the signal sequence to each polarization element of the N transmission antennas;
A phase value setting step for setting a phase value for each signal sequence so that the correlation of each signal sequence transmitted from each polarization element of N transmit antennas is minimized at the position of the terminal to be evaluated; ,
A transmission step of transmitting each signal series having a phase value set in the phase value setting step from each polarization element of N transmission antennas;
The signal transmission method for multi-antenna evaluation which performs. The signal transmission method for multi-antenna evaluation according to claim 5,
A signal transmission method for multi-antenna evaluation, further executing a power adjustment step of adjusting the power of each signal sequence by a variable attenuator between the distribution step and the transmission step. In the multi-antenna evaluation signal transmission method according to claim 5 or 6,
M = 2, N = 4,
Each transmission antenna is arranged in the order of the first transmission antenna and the third transmission antenna in the clockwise direction with respect to the reference point on the circumference on the circumference around the terminal to be evaluated, and in the counterclockwise direction. Arranged in the order of the second transmission antenna, the fourth transmission antenna,
In the distributing step, the first signal sequence is input to the vertical polarization elements of the first and fourth transmission antennas and the horizontal polarization elements of the second and third transmission antennas, and the second and third transmissions are performed. Distributing each signal sequence so that the second signal sequence is input to the vertical polarization element of the antenna and the horizontal polarization element of the first and fourth transmission antennas;
The phase value setting step uses the phase of the signal sequence radiated from the vertical polarization element of the first transmission antenna as a reference and the phase of the signal sequence radiated from the vertical polarization element of the fourth transmission antenna. a1 degree or -a1 degree, the phase of the signal series radiated from the horizontal polarization element of the second transmission antenna is a2 degrees or -a2 degrees, the phase of the signal series radiated from the horizontal polarization element of the third transmission antenna The phase is set to a3 degrees or −a3 degrees, the phase of the signal sequence radiated from the horizontal polarization element of the first transmission antenna is set to α (α is arbitrary), and the horizontal deviation of the fourth transmission antenna is set. The phase of the signal sequence radiated from the wave element is α + b1 degrees or α−b1 degrees, the phase of the signal sequence radiated from the vertical polarization element of the second transmitting antenna is α + b2 degrees or α−b2 degrees, and the third The phase of the signal sequence radiated from the vertical polarization element of the transmitting antenna is α + b3 degrees or Multi-antenna evaluating signal transmission method for setting the -b3 degrees. In the multi-antenna evaluation signal transmission method according to claim 5 or 6,
M = 2, N = 4,
Each transmitting antenna has a center angle of -A / 2 degrees (A is arbitrary) with respect to a reference point on the circumference on the circumference centered on the terminal to be evaluated, and the second Are arranged such that the transmitting antenna has a central angle of A / 2 degrees, the third transmitting antenna has a central angle of -3A / 2 degrees, and the fourth transmitting antenna has a central angle of 3A / 2 degrees. ,
In the distributing step, the first signal sequence of the fading emulator is input to the vertical polarization elements of the first and fourth transmission antennas and the horizontal polarization elements of the second and third transmission antennas, Distributing each signal sequence so that the second signal sequence is input to the vertical polarization element of the third transmission antenna and the horizontal polarization element of the first and fourth transmission antennas;
In the phase value setting step, the vertical offset of the first transmission antenna is set with reference to the phase of the signal sequence radiated from the horizontal polarization element of the third transmission antenna and the vertical polarization element of the fourth transmission antenna. Set the phase of the signal sequence radiated from the wave element to a1 'or -a1' degree, and set the phase of the signal sequence radiated from the horizontal polarization element of the second transmitting antenna to -a1 'or a1' degree The phase of the signal sequence radiated from the vertical polarization element of the third transmission antenna and the horizontal polarization element of the fourth transmission antenna is set to α degrees (α is arbitrary), and the first transmission antenna The phase of the signal sequence radiated from the horizontal polarization element is set to α−b1 ′ degree or α + b1 ′ degree, and the phase of the signal series radiated from the vertical polarization element of the second transmitting antenna is set to α + b1 ′ degree. Or the signal transmission method for multi-antenna evaluation set to (alpha) -b1 'degree.

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