CN105790893A - Method for sensing sight distance propagation environment and propagation method and device - Google Patents

Abstract

The invention discloses a method for sensing a sight distance propagation environment and a propagation method and device. The method comprises the steps of obtaining a signal measurement result, determining a transmission delay according to the signal measurement result, obtaining delay and/or power properties of each path channel in a time domain multipath channel, then determining a main path channel of the time domain multipath channel according to the transmission delay and the delay and/or power properties of the time domain multipath channel, determining a main path window according to the main path channel, and determining whether the propagation environment is the sight distance propagation environment according to a power sum of all path channels in the main path window and the power sum of all channel channels beyond the main path window. According to the method disclosed by the invention, the type of the propagation environment is determined by the signal measurement result, so that a sending end adaptively selects different multi-data stream propagation modes according to the determined propagation environment.

Description

A kind of method of perception line-of-sight propagation environment, transmission method and device

Technical field

The present invention relates to communication technical field, particularly relate to a kind of method of perception line-of-sight propagation environment, transmission method and device.

Background technology

MIMO (MultipleInputMultipleOutput, multiple-input and multiple-output) technology refers to the multiple antennas each independently transmitted signal utilizing transmitting terminal, receives with multiple antennas at receiving terminal simultaneously and recovers prime information.

Space division multiplexing technology in mimo system refers to, at transmitting terminal, the data stream of two-forty is partitioned the sub data flow of multiple relatively low rate, and different sub data flows is launched on different transmit antennas in similar frequency bands.If the sub-channel in spatial domain constituted between transmitting terminal and the aerial array of receiving terminal is enough different, namely the dimension in spatial domain can be additionally provided outside time domain and frequency domain, make can be mutually distinguishable between the signal transmitted on different transmitting antennas, therefore receiver can distinguish the sub data flow that these are parallel, without paying extra frequency or time resource.Space division multiplexing technology in mimo system improves in spectrum efficiency, the message transmission rate of raising user, lifting network transmission capacity etc. highly effective at moving communicating field.

In the space division multiplexing technology of existing low-frequency range (below 3GHz) mobile communication, antenna array is larger in size, there is substantial amounts of specular scattering signal environment in the transmission channel between multichannel transmitting terminal and multipath reception end, make signal can carry out parallel data transmission along multiple parallel associated transmission channel, use space division multiplexing technology can promote spectrum efficiency in such cases.

Mobile communication system is developed so far, and carrier frequency, always at below 3GHz, will need to use the mobile communication that higher frequency section even millimere-wave band (10-300GHz) is carrier frequency future.Millimere-wave band signal propagation characteristics is different from low-frequency range, under line-of-sight propagation environment, adopts space division multiplexing can improve spectrum efficiency, and under non-line-of-sight propagation environment, propagation loss is big and is vulnerable to object stop, it is impossible to use spatial division multiplexing to be used for improving spectrum efficiency.

Therefore, in millimere-wave band situation, it is necessary to the type of perception communication environments, thus adopting corresponding transmission means to improve spectrum efficiency.

Summary of the invention

The embodiment of the present invention provides a kind of method of perception line-of-sight propagation environment, transmission method and device, in order to realize perception line-of-sight propagation environment, and the circulation way of adaptive selection multiple data stream.

A kind of method embodiments providing perception line-of-sight propagation environment, including:

Obtain signal measurement result, and determine propagation delay time according to signal measurement result；

Obtain time delay and/or the power characteristic of every footpath channel in time domain multipath channel；

Time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determine main footpath window according to main footpath channel；

The power sum of the power sum according to all footpaths channel in the window of described main footpath and described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

Propagation delay time is determined according to signal measurement result it is preferred that described, including:

The transmitting terminal path loss power to receiving terminal is determined according to signal measurement result；

According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；

According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.

It is preferred that determine the transmitting terminal propagation distance to receiving terminal according to below equation:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

It is preferred that the described time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, including:

Delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.

It is preferred that the footpath channel in the window of described main footpath includes described main footpath channel and the adjacent footpath channel centered by the channel of described main footpath.

It is preferred that the power sum of the described power sum according to the footpath channel in the window of described main footpath and described main footpath footpath channel outside window, it is determined whether it is line-of-sight propagation environment, including:

If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, it is determined that communication environments is line-of-sight propagation environment.

It is preferred that described threshold value is determined by one below or combination in any:

The frequency of carrier wave, system bandwidth, propagation distance；

The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；

The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；

The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

It is preferred that after determining line-of-sight propagation environment, also include:

By the type notification of communication environments determined to transmitting terminal.

The embodiment of the present invention additionally provides a kind of transmission method realized based on said method, including:

Obtaining the type of communication environments, the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment；

Type according to described communication environments carries out the propagation of multiple data stream.

It is preferred that the described type according to described communication environments carries out the propagation of multiple data stream, including:

If the type of described communication environments is line-of-sight propagation environment, then space division multiplexing is adopted to carry out the propagation of multiple data stream；

If the type of described communication environments is non-line-of-sight propagation environment, then wave beam forming is adopted to carry out the propagation of multiple data stream.

If it is preferred that the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or service quality QoS requirements is high, then adopt space diversity to propagate.

The embodiment of the present invention additionally provides the device of a kind of perception line-of-sight propagation environment, including:

First acquiring unit, is used for obtaining signal measurement result, and determines propagation delay time according to signal measurement result；

Second acquisition unit, for obtaining time delay and/or the power characteristic of every footpath channel in time domain multipath channel；

First processing unit, for the time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determines main footpath window according to main footpath channel；

3rd processing unit, for the power sum of the power sum according to all footpaths channel in the window of described main footpath with described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

It is preferred that described first acquiring unit specifically for:

The transmitting terminal path loss power to receiving terminal is determined according to signal measurement result；

According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；

According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.

It is preferred that described first acquiring unit specifically for:

The transmitting terminal propagation distance to receiving terminal is determined according to below equation:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

It is preferred that described first processing unit specifically for:

Delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.

It is preferred that the footpath channel in the window of described main footpath includes described main footpath channel and the adjacent footpath channel centered by the channel of described main footpath.

It is preferred that described second processing unit specifically for:

If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, it is determined that communication environments is line-of-sight propagation environment.

It is preferred that described threshold value is determined by one below or combination in any:

The frequency of carrier wave, system bandwidth, propagation distance；

The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；

The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；

The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

It is preferred that described second processing unit is additionally operable to:

By the type notification of communication environments determined to transmitting terminal.

The embodiment of the present invention additionally provides a kind of transmission device, including:

Acquiring unit, for obtaining the type of communication environments, the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment；

Propagation unit, for carrying out the propagation of multiple data stream according to the type of described communication environments.

It is preferred that described propagation unit specifically for:

If the type of described communication environments is line-of-sight propagation environment, then space division multiplexing is adopted to carry out the propagation of multiple data stream；

If the type of described communication environments is non-line-of-sight propagation environment, then wave beam forming is adopted to carry out the propagation of multiple data stream.

It is preferred that described propagation unit specifically for:

If the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or service quality QoS requirements is high, then adopt space diversity to propagate.

In above-described embodiment, first signal measurement result is obtained, and determine propagation delay time according to signal measurement result, obtain time delay and/or the power characteristic of every footpath channel in time domain multipath channel, then according to the time delay of described propagation delay time and described time domain multipath channel and/or power characteristic, determine the main footpath channel of time domain multipath channel, and determine main footpath window according to main footpath channel, power sum further according to power sum and described main footpath all footpaths channel outside window of all footpaths channel in the window of described main footpath, it is determined whether be line-of-sight propagation environment.The embodiment of the present invention determines the type of communication environments by signal measurement result, in order to transmitting terminal selects different multiple data stream circulation ways according to the type self adaption of the communication environments determined.

Accompanying drawing explanation

In order to be illustrated more clearly that the technical scheme in the embodiment of the present invention, below the accompanying drawing used required during embodiment is described is briefly introduced, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the schematic flow sheet of a kind of method of perception line-of-sight propagation environment in the embodiment of the present invention；

Fig. 2 is the schematic flow sheet of a kind of transmission method based on method described in Fig. 1 in the embodiment of the present invention；

Fig. 3 is the antenna array structure schematic diagram of a kind of space division multiplexing circulation way in the embodiment of the present invention；

Fig. 4 is the structural representation of the device of a kind of perception line-of-sight propagation environment in the embodiment of the present invention；

Fig. 5 is the structural representation of a kind of transmission device in the embodiment of the present invention；

Fig. 6 is the structural representation of the device of another kind of perception line-of-sight propagation environment in the embodiment of the present invention；

Fig. 7 is the structural representation of another kind of transmission device in the embodiment of the present invention.

Detailed description of the invention

In order to make the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, the present invention is described in further detail, it is clear that described embodiment is only some embodiments of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, all other embodiments that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of protection of the invention.

In mimo systems, space division multiplexing technology can improve spectrum efficiency, meets Gbps (1000 megabits per second) the DBMS transmission rate request of user.Especially, when meeting line-of-sight transmission, space division multiplexing technology is adopted can be effectively improved spectrum efficiency.Therefore, in order to space division multiplexing technology can be used under high data rate to improve spectrum efficiency, it is necessary to whether the type first determining communication environments is line-of-sight propagation environment.

To achieve these goals, Fig. 1 illustrates the flow process of a kind of perception line-of-sight propagation environment, and this flow process can be performed by the device of perception line-of-sight propagation environment, and this device can be terminal, it is also possible to be other access devices, such as access point.This device can also is that base station, and described base station refers to the equipment with base station functions, such as moves platform.

Millimeter wave mobile telecommunication channel condition is continually changing, it is necessary to judge whether current propagation environment is line-of-sight propagation environment by measuring, in order to adopt space division multiplexing technology to improve spectrum efficiency under line-of-sight propagation environment.

As it can be seen, these flow process concrete steps include:

Step S101, obtains signal measurement result, and determines propagation delay time according to signal measurement result.

As it was previously stated, the executive agent of this flow process can be terminal can also be base station.If the executive agent of this flow process is terminal, then in step S101, terminal carries out signal measurement, obtains signal measurement result, and determines that the propagation delay time of this terminal is arrived in base station according to signal measurement result；If the executive agent of this flow process is base station, then in step S101, terminal carries out signal measurement and measurement result is sent to base station, and the propagation delay time between this terminal and this base station is determined according to signal measurement result after obtaining signal measurement result in base station.

Specifically, it is thus achieved that after signal measurement result, path loss power can be determined according to measurement result, determine propagation distance further according to described path loss power, then according to described propagation distance, it is determined that propagation delay time.

Send data with base station, terminal receives data instance, and the transmission resource notification of public guide frequency or reference signal to terminal, and is sent public guide frequency or reference signal by base station on the resource, and transmission power value is static or semi-static systematic parameter P_out。

Terminal receives public guide frequency or reference signal on the resource, carries out Base-Band Processing to the received signal, obtains the reception power P of public guide frequency or reference signal_r, then calculate and obtain path loss P_lossFor:

P_loss=P_out-P_r

After determining path loss, determine the propagation distance d between the antenna of base station and the antenna of terminal according to free-space propagation formula:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)\·\·\·\left(1\right)$

Wherein, P_lossFor path loss, d is propagation distance, and λ is the wavelength of carrier wave frequency range.

After determining propagation distance, propagation delay time can be determined according to propagation distance.Such as, propagation distance d is 2.8m, signal velocity s is 3 × 10⁸M/s, then propagation delay time is:

Transmission range d ÷ signal velocity s ≈ 10ns ... ... ... ... ... ... (2)

Step S102, obtains time delay and/or the power characteristic of every footpath channel in time domain multipath channel.

At wireless communication field, from the radio wave that transmitter antenna is launched, the propagation phenomenon arriving receiver antenna along two or more paths is called that multi-path ripple transmits, referred to as Multipath Transmission.Radio wave is a kind of electromagnetic wave, and the major way of its propagation is space wave, i.e. direct wave, echo, refracted wave, diffracted wave and their composite wave.When radio wave runs into object, produce reflection, refraction and scattering, and different objects can be run in the process of radio wave propagation, thus different transmitting, refraction and scatterings can be produced, point is all likely to receive the same source and electromagnetic wave from different paths so receiving at any one.Atmosphere is to the scattering of electric wave, ionosphere to the reflection of electric wave and refraction, and the reflection of electric wave all can be caused Multipath Transmission by the earth's surface such as the chain of mountains, building object.

Arrive receiving terminal between these multi-path ripples and have a little time difference, be called multidiameter delay characteristic or power characteristic.Multidiameter delay characteristic or power characteristic can describe with delay profile or multipath spread spectrum, and wherein, multipath spread spectrum is the spectrum of the component of signal mean power composition of different delay.Of equal value with delay profile is frequency correlation function.In multipath channel models, each footpath channel is given to the type of its relative time, average relative power and its doppler spectral.It is adopt time delay power spectrum that description multipath power is distributed another method, and it describes under different multidiameter delay, the value of multipath power.

The embodiment of the present invention does not limit to the time delay and/or power characteristic describing multipath for adopting which kind of mode.

Estimated by time domain multipath channel, analyze channel impulse response, time delay and/or the power characteristic of every time domain multipath channel can be obtained.Multi-path detecting method has multiple, and this is not limited as by the embodiment of the present invention.

Such as, in the implementation that a kind of multipath detects, single for ofdm system symbol pilot sub-carrier is carried out LS (LeastSquare, least square or least square) channel estimating, then the channel estimation in frequency domain obtained is smoothed at intersymbol, and then it is relevant to carry out frequency domain, by the result after relevant by Inverse Fast Fourier Transforms territory algorithmic transformation to time domain, finally carry out time domain multipath channel analysis, determine time delay and/or the power characteristic of time domain multipath channel, it is also possible to be called time delay power spectrum.

Step S103, according to the time delay of described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determines main footpath window according to main footpath channel.

In the present embodiment, owing to propagation delay time is to calculate according to the distance between transmitting terminal antenna and receiving terminal antenna and electric wave (signal) spread speed to obtain, namely can be considered the propagation delay time in the path that direct transfers, the described path that direct transfers is that the electric wave that transmitting terminal antenna sends directly arrives receiving terminal antenna, the middle transmission path do not blocked.The time delay of time domain multipath channel is immediate footpath channel with the propagation delay time in the path that direct transfers, and is main footpath.

Concrete, after the time delay determining propagation delay time and time domain multipath channel and/or power characteristic, can according to the time delay of described time domain multipath channel, by wherein time delay closest to the step S101 propagation delay time calculated and the footpath channel being not less than the step S101 propagation delay time calculated, it is determined that be main footpath channel.Wherein, the time delay of described time domain multipath channel and/or power characteristic can represent with time delay power spectrum.

Such as, delay resolution in time delay power spectrum is 10ns, then the time delay of the 1st article of footpath channel is 10ns, article 2, the time delay of footpath channel is 20ns ..., the time delay of the N article footpath channel is 10 × Nns, if the propagation delay time determined in step S101 is 9.3ns, then determine that the 1st article of footpath channel is main footpath channel, if the propagation delay time determined in step S101 is 46.7ns, it is determined that the 5th article of footpath channel is main footpath channel.

Step S104, the power sum according to the power sum of all footpaths channel in the window of described main footpath Yu described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

In the present embodiment, electric wave through the path transmission that direct transfers, in transmitting procedure, it is sent by holding and directly arrives receiving terminal, not past reflection, refraction and scattering, therefore path loss is smaller, and the power that receiving terminal receives also is maximum, and other echo, refracted wave and scattered waves etc. arrived through reflection, refraction and scattering, long transmission distance.Transmission range is more remote, and power attenuation is more big, and the power that receiving terminal receives electric wave is also more little.The ratio of the power of the electric wave that the power of the electric wave therefore arrived by the path that direct transfers is arrived with reflection path, refraction path and scattering path is more than a threshold value, it may be determined that the environment of current communication environments is line-of-sight propagation environment.

Wherein, described threshold value is determined by one of the frequency of carrier wave, system bandwidth and propagation distance etc. or combination, and the threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.The frequency of described carrier wave is more high, and the wavelength of its carrier wave is more little, and the power of corresponding path loss is more big, then threshold value setting is also more big；Described propagation distance is more remote, and the power of its path loss is more big, then threshold value setting is also more big, as being in 50MHz in system bandwidth, if the distance of transmitting terminal and receiving terminal is 2.8m, then can set that threshold value is 5, if the distance of transmitting terminal and receiving terminal is 14m, then can set that threshold value is 10；If after obtaining the time delay of time domain multipath channel and/or power characteristic, low-power carrier signal being carried out return-to-zero, namely go to the end to make an uproar process, then the impact of the value of described threshold value can be ignored by described system bandwidth；If after obtaining the time delay of time domain multipath channel and/or power characteristic, low-power carrier signal is not gone the end make an uproar processs, then system bandwidth is more big, its corresponding threshold value setting more big.The frequency of the above-mentioned carrier wave determining described threshold value, system bandwidth and propagation distance can carry out combination in any.

In the present embodiment, the main footpath window of described main footpath channel can use window function to choose.The window function used may include but be not limited to rectangular window function.For reducing due to the introduced error of signal sampling, the limited precision of power spectrum, it is necessary to select main footpath window rather than single footpath can know the general power in direct-view footpath more accurately.Main footpath needs to select with the time delay value Article 1 footpath more than the time delay value obtained measured by path loss, and selects adjacent footpath for start-stop position centered by this footpath.In the application scenarios of sighting distance space division multiplexing, user and base station distance are relatively near, and general, window length is chosen as 3～5.

For example, it is possible to select two footpath channels adjacent with main footpath channel as the start-stop position of main footpath window.

Preferably, if the ratio of the power sum of the power sum of all footpaths channel in the window of main footpath and described main footpath all footpaths channel outside window is more than threshold value, then may determine that the type of current communication environments is line-of-sight propagation environment；If the ratio of the power sum of the power sum of all footpaths channel in the window of main footpath and described main footpath all footpaths channel outside window is less than or equal to this threshold value, it may be determined that the type of current communication environments is non-line-of-sight propagation environment.

Preferably, after step s 104, can comprise the further steps of:

By the type notification of communication environments determined to transmitting terminal, so that described transmitting terminal carries out the propagation of multiple data stream according to the type of communication environments, transmitting terminal can according to the propagation carrying out multiple data stream of the type self adaption of communication environments.

In above-described embodiment, first signal measurement result is obtained, and determine propagation delay time according to signal measurement result, obtain time delay and/or the power characteristic of every footpath channel in time domain multipath channel, then according to the time delay of described propagation delay time and described time domain multipath channel and/or power characteristic, determine the main footpath channel of time domain multipath channel, and determine main footpath window according to main footpath channel, power sum further according to power sum and described main footpath all footpaths channel outside window of all footpaths channel in the window of described main footpath, it is determined whether be line-of-sight propagation environment.The embodiment of the present invention determines the type of communication environments by signal measurement result, in order to transmitting terminal selects different multiple data stream circulation ways according to the type self adaption of the communication environments determined.

Fig. 2 illustrates the flow process of a kind of transmission method, and this flow process can be performed by transmission device, and this device can be base station, it is also possible to be terminal.As it can be seen, the concrete steps of this flow process include:

Step S201, obtains the type of communication environments, and the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment.

If the executive agent of this flow process is terminal, then this terminal the flow process shown in Fig. 1 can determine the type of current communication environments；If the executive agent of this flow process is base station, then terminal can by the type notification of current communication environments determined to this base station, or, signal measurement result is sent to this base station by terminal, this base station determine the type of current communication environments according to signal measurement result flow process shown in Fig. 1.

Step S202, carries out the propagation of multiple data stream according to the type of described communication environments.

Concrete, however, it is determined that the type of the communication environments gone out is line-of-sight propagation environment, then adopt space division multiplexing to carry out the propagation of multiple data stream；If it is determined that communication environments type be non-line-of-sight propagation environment, then adopt wave beam forming to carry out the propagation of multiple data stream.Further, however, it is determined that the communication environments type gone out is line-of-sight propagation environment, and the data volume transmitted is smaller or QoS (QualityofService, service quality) requires height, then can adopt transmission diversity.Under line-of-sight propagation environment, adopt space division multiplexing can provide spectrum efficiency, transmission data volume is smaller or during qos requirement height, adopts and sends diversity and can obtain diversity gain, improve receiving sensitivity.Under non-line-of-sight propagation environment, adopt wave beam forming can compensate propagation loss.

For base station, type according to communication environments carries out the propagation of multiple data stream, base station utilizes aerial array information to carry out a day line options, select to be not more than antenna submatrix corresponding to L roadbed band signal and send pilot tone or reference signal, be wherein L road as the digital baseband passage in the terminal of receiving terminal.

Preferably, base station is make antenna submatrix distance interval big as far as possible in the principle selecting antenna submatrix.This is because according to MIMO principle, under determining space scattering environment, owing to the spatial degrees of freedom of space channel depends on the aperture of aerial array, can pass through to adjust flexibly the mode of transmitting terminal and receiving terminal multiple antennas spacing, thus structure is applicable to line-of-sight transmission environment, realize multiple data stream parallel transmission under line-of-sight propagation environment, improve spectrum efficiency and efficiency of transmission.

If as it is shown on figure 3, aerial array is linear array, when meeting full rank transmission conditions, the quantity of the transmitting data in parallel stream Ns that space division multiplexing is supported can according to formulaObtain, wherein, L_TAnd L_RThe respectively total length of the total length of transmitting terminal antenna and receiving terminal antenna, R is the distance between transmitting terminal and receiving terminal, and λ is the wavelength of carrier wave frequency range.From formula it can be seen that under line-of-sight propagation environment, the quantity of multiple data stream transmission will depend upon which the distance of the total length of transmission antenna and the total length of reception antenna, transmitting terminal and receiving terminal and the wavelength of carrier wave frequency range.

In above-described embodiment, carry out the propagation of multiple data stream according to the type of the communication environments of transmitting terminal transmission.Can be implemented under different communication environments, propagated by different modes, it is possible to the suitable circulation way of adaptive selection is propagated.

In order to better explain the present invention, practice scene below in conjunction with concrete, it is provided that under concrete application scenarios, determine the implementation process of the type of communication environments.

(1) application scenarios of multi-carrier OFDM (OrthogonalFrequencyDivisionMultiplexing, OFDM) modulation system

In multi-carrier OFDM modulation system, carrier frequency is 10GHz, and system bandwidth is under the scene of 50MHz.Pilot sub-carrier is utilized to carry out LS channel estimating, carry out frequency domain to be correlated with, it is then converted to time domain and carries out the analysis of time domain multipath channel, obtaining time delay power spectrum, the time delay of time domain multipath channel can be represented by tap delays line, and the delay resolution between tap is the inverse of sample rate, with the system bandwidth of 2 times for sample rate, delay resolution is 10ns (i.e. 1/50x2MHz), and namely the time delay spacing between each footpath channel is 10ns, obtains the linear power value of each footpath channel simultaneously.If the propagation distance obtained by path loss is 2.8m, then propagation delay time is 9.3ns, propagation delay time is less than 10ns, therefore, needing to select the 1st article of footpath channel (time delay 10ns) is main footpath channel, the 2nd article of footpath channel taking main footpath channel adjacent is main footpath window, calculates power and the P of all footpaths channel in the window of main footpath₀And the power sum P of all footpaths channel that main footpath is outside window₁, P₀/P₁The i.e. 10logP more than 5₀/P₁More than 7dB, namely can determine that the type of communication environments is line-of-sight propagation environment, meet the condition of space division multiplexing；If the propagation distance obtained by path loss is 14m, then propagation delay time is 46.7ns, needing to select the 5th article of footpath channel (time delay is 50ns) is main footpath channel, take the 4th article of adjacent footpath channel of main footpath channel and the 6th article of footpath channel is main footpath window, calculate power and the P of all footpaths channel in the window of main footpath₀And the power sum P of all footpaths channel that main footpath is outside window₁, work as P₀/P₁During more than 10 and 10logP₀/P₁More than 10dB, namely can determine that the type of communication environments is line-of-sight propagation environment, it is believed that meet the condition of space division multiplexing, if the propagation distance that path loss obtains is 25m, then propagation delay time is 66.7ns, needing to select the 7th article of footpath channel (time delay 70ns) is main footpath channel, and the 6th article of adjacent footpath channel and the 8th article of footpath channel are main footpath window, calculate power and the P of all footpaths channel in the window of main footpath₀And the power sum P of all footpaths channel that main footpath is outside window₁, work as P₀/P₁During more than 20 and 10logP₀/P₁More than 13dB, namely can determine that the type of communication environments is line-of-sight propagation environment, it is believed that meet the condition of space division multiplexing.

After the type determining communication environments is line-of-sight propagation environment, transmitting terminal can adopt the mode of space division multiplexing to carry out the propagation of multiple data stream.

In multi-carrier OFDM modulation system, carrier frequency 28GHz, under the scene of system bandwidth 500MHz.Pilot sub-carrier is utilized to carry out LS channel estimating, carry out frequency domain to be correlated with, it is then converted to time domain and carries out the analysis of time domain multipath channel, obtaining time delay power spectrum, the time delay of time domain multipath channel can be represented by tap delays line, and the delay resolution between tap is the inverse of sample rate, sample rate value is equal to system bandwidth, delay resolution is up to 2ns, and namely the time delay spacing between each footpath channel is 2ns, obtains the linear power value of each footpath channel simultaneously.If the propagation distance obtained by path loss is 4m, then propagation delay time is 13.3ns, selecting the 7th article of footpath channel (time delay 14ns) is main footpath channel, and the 6th article of adjacent footpath channel and the 8th article of footpath channel are main footpath window, calculate power and the P of all footpaths channel in the window of main footpath₀And the power sum P of all footpaths channel that main footpath is outside window₁, work as P₀/P₁The i.e. 10logP more than 5₀/P₁More than 7dB, namely can determine that the type of communication environments is line-of-sight propagation environment, it is believed that meet the condition of space division multiplexing.

(2) single carrier SC-FDMA (Single-carrierFrequency-DivisionMultipleAccess, single-carrier frequency division multiple access) adjusts the application scenarios of mode

In single carrier SC-FDMA modulation system, carrier frequency is under the scene of 45GHz, system bandwidth 1080MHz.Pilot sub-carrier is utilized to carry out LS channel estimating, carry out frequency domain to be correlated with, it is then converted to time domain and carries out the analysis of time domain multipath channel, obtain time delay power spectrum, the multidiameter delay of time domain multipath channel can be represented by tap delays line, delay resolution between tap is the inverse of sample rate, sample rate value is equal to system bandwidth, delay resolution is up to 0.93ns, if the propagation distance obtained by path loss is 5m, then propagation delay time is 16.7ns, selecting the 18th article of footpath channel (time delay 16.74ns) is main footpath channel, the 17th article of adjacent footpath channel and the 19th article of footpath channel are main footpath window, calculate power and the P of all footpaths channel in the window of main footpath₀And the power sum P of all footpaths channel that main footpath is outside window₁, work as P₀/P₁The i.e. 10logP more than 5₀/P₁More than 7dB, namely can determine that the type of communication environments is line-of-sight propagation environment, it is believed that meet the condition of space division multiplexing.

Based on identical inventive concept, Fig. 4 illustrates the device of a kind of perception line-of-sight propagation environment, and this device can perform the flow process shown in Fig. 1, and this device can be terminal, it is also possible to be other access devices, such as access point.This device can also is that base station, and described base station refers to the equipment with base station functions, such as moves platform.As it can be seen, this device includes:

First acquiring unit 401, is used for obtaining signal measurement result, and determines propagation delay time according to signal measurement result；

Second acquisition unit 402, for obtaining time delay and/or the power characteristic of every footpath channel in time domain multipath channel；

First processing unit 403, for the time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determines main footpath window according to main footpath channel；

Second processing unit 404, for the power sum of the power sum according to all footpaths channel in the window of described main footpath with described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

Preferably, described first acquiring unit 401 specifically for:

The transmitting terminal path loss power to receiving terminal is determined according to signal measurement result；

According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；

According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.

Preferably, described first acquiring unit 401 specifically for:

The transmitting terminal propagation distance to receiving terminal is determined according to below equation:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)---\left(1\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

Preferably, described first processing unit 403 specifically for:

Delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.

Preferably, the footpath channel in the window of described main footpath includes described main footpath channel and the adjacent footpath channel centered by the channel of described main footpath.

Preferably, described second processing unit 404 specifically for:

If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, it is determined that communication environments is line-of-sight propagation environment.

Preferably, described threshold value is determined by one below or combination in any:

The frequency of carrier wave, system bandwidth, propagation distance；

The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；

The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；

The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

Preferably, described second processing unit 404 is additionally operable to:

By the type notification of communication environments determined to transmitting terminal.

Fig. 5 illustrates a kind of transmission device, and this device can perform the flow process shown in Fig. 2, and this device can be base station, it is also possible to be terminal.As it can be seen, this device includes:

Acquiring unit 501, for obtaining the type of communication environments, the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment；

Propagation unit 502, for carrying out the propagation of multiple data stream according to the type of described communication environments.

Preferably, described propagation unit 502 specifically for:

If the type of described communication environments is line-of-sight propagation environment, then space division multiplexing is adopted to carry out the propagation of multiple data stream；

If the type of described communication environments is non-line-of-sight propagation environment, then wave beam forming is adopted to carry out the propagation of multiple data stream.

Preferably, described propagation unit 502 specifically for:

If the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or qos requirement is high, then adopt space diversity to propagate.

The structural representation of the device of the another kind of perception line-of-sight propagation environment that Fig. 6 provides for the embodiment of the present invention, this device can realize the method that the above embodiment of the present invention provides.This device comprises the steps that bus and the bridge of any number of interconnection, and the various electrical chains of the memorizer that the one or more processors specifically represented by processor 601 and memorizer 603 represent are connected together.Other electrical chains various of such as ancillary equipment, manostat and management circuit or the like can also be connected together by bus architecture, and these are all it is known in the art, therefore, no longer it are described further herein.EBI provides interface, and transceiver 604 can be multiple element, namely includes transmitter and transceiver, it is provided that for the unit communicated with other devices various over a transmission medium.Processor 601 is responsible for bus architecture and common process, and memorizer 603 can store the data that processor 601 uses when performing operation.Display 602 can be CRT (CathodeRayTube, cathode ray tube), PDP (PlasmaDisplayPanel, plasma display), DLP (DigitalLightProcession, digital light processes) or the display device such as LCD (LiquidCrystalDisplay, LCDs).

Processor 601, for reading the program in memorizer 603, performs following process: transceiver 604 obtains signal measurement result, and processor 601 determines propagation delay time according to signal measurement result.Concrete, processor 601 determines the transmitting terminal path loss power to receiving terminal according to signal measurement result；According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.Processor 601 determines the transmitting terminal propagation distance to receiving terminal according to below equation (1):

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)\·\·\·\left(1\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

Processor 601 obtains time delay and/or the power characteristic of every footpath channel in time domain multipath channel；Processor 601 is according to the time delay of described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, processor 601 determines main footpath window according to main footpath channel；The power sum of the processor 601 power sum according to all footpaths channel in the window of described main footpath and described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

Concrete, the processor 601 delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, then processor 601 determines that communication environments is line-of-sight propagation environment.Processor 601 also by the communication environments type notification determined to transmitting terminal.Wherein, described threshold value is determined by one below or combination in any: the frequency of carrier wave, system bandwidth, propagation distance；The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

Memorizer 603, is used for storing one or more executable program, is used to configure described processor 601.

The structural representation of the another kind of transmission device that Fig. 7 provides for the embodiment of the present invention, this device can realize the method that the above embodiment of the present invention provides.This device comprises the steps that bus and the bridge of any number of interconnection, and the various electrical chains of the memorizer that the one or more processors specifically represented by processor 701 and memorizer 703 represent are connected together.Other electrical chains various of such as ancillary equipment, manostat and management circuit or the like can also be connected together by bus architecture, and these are all it is known in the art, therefore, no longer it are described further herein.EBI provides interface, and transceiver 705 can be multiple element, namely includes transmitter and transceiver, it is provided that for the unit communicated with other devices various over a transmission medium.Processor 701 is responsible for bus architecture and common process, and memorizer 703 can store the data that processor 701 uses when performing operation.For different subscriber equipmenies, user interface 704 can also is that can external in connect the interface needing equipment, the equipment of connection includes but not limited to keypad, speaker, mike, stick etc..Display 702 can be the display devices such as CRT, PDP, DLP or LCD.

Processor 701, for reading the program in memorizer 703, performs following process: transceiver 705 obtains the type of communication environments, and the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment.Processor 701 carries out the propagation of multiple data stream according to the type of described communication environments.

Concrete, if the type of described communication environments is line-of-sight propagation environment, then processor 701 adopts space division multiplexing to carry out the propagation of multiple data stream；If the type of described communication environments is non-line-of-sight propagation environment, then processor 701 adopts wave beam forming to carry out the propagation of multiple data stream.If the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or qos requirement is high, then processor 701 adopts space diversity to propagate.

Memorizer 703, is used for storing one or more executable program, is used to configure described processor 701.

The present invention is that flow chart and/or block diagram with reference to method according to embodiments of the present invention, equipment (system) and computer program describe.It should be understood that can by the combination of the flow process in each flow process in computer program instructions flowchart and/or block diagram and/or square frame and flow chart and/or block diagram and/or square frame.These computer program instructions can be provided to produce a machine to the processor of general purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device so that the instruction performed by the processor of computer or other programmable data processing device is produced for realizing the device of function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

These computer program instructions may be alternatively stored in and can guide in the computer-readable memory that computer or other programmable data processing device work in a specific way, the instruction making to be stored in this computer-readable memory produces to include the manufacture of command device, and this command device realizes the function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

These computer program instructions also can be loaded in computer or other programmable data processing device, make on computer or other programmable devices, to perform sequence of operations step to produce computer implemented process, thus the instruction performed on computer or other programmable devices provides for realizing the step of function specified in one flow process of flow chart or multiple flow process and/or one square frame of block diagram or multiple square frame.

Although preferred embodiments of the present invention have been described, but those skilled in the art are once know basic creative concept, then these embodiments can be made other change and amendment.So, claims are intended to be construed to include preferred embodiment and fall into all changes and the amendment of the scope of the invention.

Obviously, the present invention can be carried out various change and modification without deviating from the spirit and scope of the present invention by those skilled in the art.So, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

Claims (22)

1. the method for a perception line-of-sight propagation environment, it is characterised in that the method includes:

Obtain signal measurement result, and determine propagation delay time according to signal measurement result；

Obtain time delay and/or the power characteristic of every footpath channel in time domain multipath channel；

Time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determine main footpath window according to main footpath channel；

The power sum of the power sum according to all footpaths channel in the window of described main footpath and described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

2. the method for claim 1, it is characterised in that described determine propagation delay time according to signal measurement result, including:

The transmitting terminal path loss power to receiving terminal is determined according to signal measurement result；

According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；

According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.

3. method as claimed in claim 2, it is characterised in that determine the transmitting terminal propagation distance to receiving terminal according to below equation:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

4. the method for claim 1, it is characterised in that the described time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, including:

Delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.

5. the method for claim 1, it is characterised in that the footpath channel in the window of described main footpath includes described main footpath channel and the adjacent footpath channel centered by the channel of described main footpath.

6. the method for claim 1, it is characterised in that the power sum of the described power sum according to the footpath channel in the window of described main footpath and described main footpath footpath channel outside window, it is determined whether be line-of-sight propagation environment, including:

If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, it is determined that communication environments is line-of-sight propagation environment.

7. method as claimed in claim 6, it is characterised in that described threshold value is determined by one below or combination in any:

The frequency of carrier wave, system bandwidth, propagation distance；

The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；

The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；

The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

8. the method as according to any one of claim 1 to 7, it is characterised in that after determining line-of-sight propagation environment, also include:

By the type notification of communication environments determined to transmitting terminal.

9. the transmission method realized based on the method as described in as arbitrary in claim 1 to 8, it is characterised in that including:

Obtaining the type of communication environments, the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment；

Type according to described communication environments carries out the propagation of multiple data stream.

10. method as claimed in claim 9, it is characterised in that the described type according to described communication environments carries out the propagation of multiple data stream, including:

If the type of described communication environments is line-of-sight propagation environment, then space division multiplexing is adopted to carry out the propagation of multiple data stream；

If the type of described communication environments is non-line-of-sight propagation environment, then wave beam forming is adopted to carry out the propagation of multiple data stream.

11. method as claimed in claim 10, it is characterised in that if the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or service quality QoS requirements is high, then adopt space diversity to propagate.

12. the device of a perception line-of-sight propagation environment, it is characterised in that including:

First acquiring unit, is used for obtaining signal measurement result, and determines propagation delay time according to signal measurement result；

Second acquisition unit, for obtaining time delay and/or the power characteristic of every footpath channel in time domain multipath channel；

First processing unit, for the time delay according to described propagation delay time and described time domain multipath channel and/or power characteristic, it is determined that the main footpath channel of time domain multipath channel, and determines main footpath window according to main footpath channel；

Second processing unit, for the power sum of the power sum according to all footpaths channel in the window of described main footpath with described main footpath all footpaths channel outside window, it is determined whether be line-of-sight propagation environment.

13. device as claimed in claim 12, it is characterised in that described first acquiring unit specifically for:

The transmitting terminal path loss power to receiving terminal is determined according to signal measurement result；

According to described path loss power, it is determined that transmitting terminal is to the propagation distance of receiving terminal；

According to signaling rate and described propagation distance, it is determined that transmitting terminal is to the propagation delay time of receiving terminal.

14. device as claimed in claim 13, it is characterised in that described first acquiring unit specifically for:

The transmitting terminal propagation distance to receiving terminal is determined according to below equation:

$P_{\mathrm{loss}}=20\log \left(\frac{4\mathrm{\πd}}{\mathrm{\λ}}\right)$

Wherein, P_lossFor the path loss of transmitting terminal to receiving terminal, d is the transmitting terminal propagation distance to receiving terminal, and λ is the wavelength of carrier wave frequency range.

15. device as claimed in claim 12, it is characterised in that described first processing unit specifically for:

Delay character according to described time domain multipath channel, by time delay closest to and be not less than the footpath channel of the propagation delay time determined according to measurement result, it is determined that be main footpath channel.

16. device as claimed in claim 12, it is characterised in that the footpath channel in the window of described main footpath includes described main footpath channel and the adjacent footpath channel centered by the channel of described main footpath.

17. device as claimed in claim 12, it is characterised in that described second processing unit specifically for:

If the ratio of the power sum of the power sum of the footpath channel in the window of described main footpath and described main footpath footpath channel outside window is more than threshold value, it is determined that communication environments is line-of-sight propagation environment.

18. device as claimed in claim 17, it is characterised in that described threshold value is determined by one below or combination in any:

The frequency of carrier wave, system bandwidth, propagation distance；

The threshold value that threshold value corresponding to the frequency of first carrier is corresponding more than the second carrier frequency, the frequency of wherein said first carrier is more than described second carrier frequency；

The threshold value that threshold value corresponding to the first system bandwidth is corresponding more than second system bandwidth, wherein said the first system band is wider than described second system bandwidth；

The threshold value that threshold value corresponding to the first propagation distance is corresponding more than the second propagation distance, wherein said first propagation distance is more than described second propagation distance.

19. the device as according to any one of claim 12 to 18, it is characterised in that described second processing unit is additionally operable to:

By the type notification of communication environments determined to transmitting terminal.

20. a transmission device, it is characterised in that including:

Acquiring unit, for obtaining the type of communication environments, the type of described communication environments includes line-of-sight propagation environment or non-line-of-sight propagation environment；

Propagation unit, for carrying out the propagation of multiple data stream according to the type of described communication environments.

21. device as claimed in claim 20, it is characterised in that described propagation unit specifically for:

If the type of described communication environments is line-of-sight propagation environment, then space division multiplexing is adopted to carry out the propagation of multiple data stream；

If the type of described communication environments is non-line-of-sight propagation environment, then wave beam forming is adopted to carry out the propagation of multiple data stream.

22. device as claimed in claim 21, it is characterised in that described propagation unit specifically for:

If the type of described communication environments is line-of-sight propagation environment, and the quantity of described multiple data stream is few or service quality QoS requirements is high, then adopt space diversity to propagate.